Dedifferentiated liposarcoma with rhabdomyoblastic differentiation

Dedifferentiated areas of dedifferentiated liposarcoma (DDL) usually show malignant fibrous histiocytoma (MFH)- or fibrosarcoma-like features and lack any histologic signs of specific differentiation. However, some reports have demonstrated specific differentiation in these areas, with histologic features resembling those of rhabdomyosarcoma, leiomyosarcoma, and osteosarcoma. We report here a pathologic and genetic analysis of three cases of DDLs with rhabdomyosarcomatous areas. MFH- or fibrosarcoma-like areas of one primary DDL and two recurrent DDLs contained various amounts of rhabdomyoblasts, which were immunoreactive for desmin, myoglobin, muscle actin (HHF-35), and myogenin. An ultrastructural examination demonstrated rhabdomyoblasts with abundant cytoplasm containing thin and thick filaments and Z-bands. By real-time PCR, amplification of mdm2 and cdk4 was confirmed in both well-differentiated and dedifferentiated areas with rhabdomyoblasts of all cases. To our knowledge, only seven cases of DDLs with rhabdomyosarcomatous components have been reported, and furthermore, the genetic profiles of the rhabdomyosarcomatous components in DDLs have not been investigated. This study demonstrates that DDLs with rhabdomyosarcomatous areas have genetic alterations that are common to well-differentiated/dedifferentiated liposarcomas.

Abrasion resistance of titanium nitride coatings formed on titanium by ion-beam-assisted deposition

To improve the physical properties of the pure titanium surface, thin titanium nitride (TiN) films were deposited by means of ion-beam-assisted deposition. Film structure was confirmed as TiN by X-ray diffraction analysis. Surface hardness and abrasion resistance were significantly improved on TiN-coated specimens. Five combinations of oral hygiene instruments and materials were applied to the specimens as simulations of the oral environment. Treatment with the metal scaler and ultrasonic scaler severely changed the surface features and significantly increased the surface roughness parameters on pure titanium controls, whereas only small scratches and dull undulations were seen on the TiN-coated specimens. Profilometric tracings and scanning electron micrographs demonstrated the improved abrasion resistance of the TiN-coated specimens.

Bonding between resin luting cement and glass infiltrated alumina-reinforced ceramics with silane coupling agent

The purpose of this study was to evaluate the shear bond strengths of three dual-cured resin luting cements (Linkmax HV, Panavia Fluoro Cement, and RelyX ARC) to glass-infiltrated alumina-reinforced ceramic material and the effect of four silane coupling agents (Clearfil Porcelain Bond, GC Ceramic Primer, Porcelain LinerM, and Tokuso Ceramic Primer) on the bond strength. The two type-shaped of In-Ceram alumina ceramic glass-infiltrated specimens were untreated or treated with one of the four ceramic primers and then cemented together with one of the three dual-cured resin luting cements. Half of the specimens were stored in water at 37 degrees C for 24 h and the other half thermocycled 20,000 times before shear bond strength testing. Surface treatment by all silane coupling agents improved the shear bond strength compared with non-treatment. The specimens treated with Clearfil Porcelain Bond showed significantly greater shear bond strength than any of the other three silane coupling agents regardless of resin luting cements and thermocycling except for the use of Panavia Fluoro Cement at 20,000 thermocycles. When the alumina-reinforced ceramic material was treated with any silane coupling agent except GC Ceramic Primer and cemented with Linkmax HV, no significant differences in bond strength were noted between after water storage and after 20,000 thermocycles. After 20,000 thermocycles, all specimens except for the combined use of Clearfil Porcelain Bond or GC Ceramic Primer and Linkmax HV and GC Ceramic Primer and Panavia Fluoro Cement showed adhesive failures at the ceramic-resin luting cement interface.

Ictal magnetoencephalographic study in a patient with ring 20 syndrome

OBJECTIVE

To report the ictal magnetoencephalography (MEG) in a patient with ring chromosome 20 mosaicism, a rare chromosomal anomaly associated with intractable epilepsy.

METHODS

MEG and simultaneous EEG were recorded with a 204 channel whole head MEG system. Ten habitual seizures occurred during the acquisition, which was done twice. The equivalent current dipoles (ECDs) for ictal discharges on MEG were calculated using a single dipole model. The ECDs were superimposed on a magnetic resonance image.

RESULTS

During the seizures, EEG showed prolonged bursts of 5-6 Hz high voltage slow waves with spike components, dominantly in the bilateral frontal region. MEG showed epileptiform discharges corresponding to the ictal EEG. Ictal discharges on MEG were dominant in the frontal area in the initial portion, and then spread in the bilateral temporal area in the middle of the seizure. ECDs obtained from the spikes of the initial portion were clustered in the medial frontal lobe.

CONCLUSIONS

The source of the ictal MEG was localised in the medial frontal lobe. The findings suggest that the mechanism underlying epilepsy in this case might be similar to medial frontal lobe epilepsy. Ictal MEG is a valuable tool for detecting the site of seizure onset.

Antioxidant property of metallothionein in fasted mice

Metallothionein (MT) is a low-molecular-weight and sulfur-rich protein that is induced by not only heavy metals but also physiological stresses such as fasting and restraint stresses. Although MT plays a role as a radical scavenger and a regulator of metabolism of metals, the biological function of MT induced by fasting stress has not been elucidated. In this study, we investigated the antioxidative role of MT in fasted mice. In fasted mice, the lipid peroxidation level of the liver was elevated by 24-h fasting stress, and pre-induction of hepatic MT by Zn diminished hepatic lipid peroxidation. Although 24-h fasting stress induced MT synthesis in the liver, other antioxidants such as catalase, manganese-superoxide dismutase (Mn-SOD), and glutathione peroxidase (GSHPx) were not activated in the liver. Moreover, the hepatic MT level was still elevated by fasting stress after seven cycles of repetition of alternate fasting and feeding every 24 h, but the activities of catalase, Mn-SOD and GSHPx were unchanged. These results indicate that MT induced by fasting stress plays partly as an antioxidant.

Impact of aging on the development of hepatocellular carcinoma in patients with hepatitis C virus infection in Japan

BACKGROUND

It is difficult to study the long-term outcome of hepatitis C virus (HCV) infection because chronic infection is often asymptomatic and duration of the disease is prolonged. The clinical outcome of HCV infection remains unclear in patients of advanced age.

METHODS

Among 575 patients consecutively diagnosed with hepatocellular carcinoma (HCC) from 1988 to 1999 at Hiroshima University, we examined 430 with HCV. We studied the differences between males and females in the following characteristics: age at first diagnosis of HCC, Child grade, various tumour factors, history of blood transfusion, duration to development of HCC, and history of alcohol intake.

RESULTS

The incidence of HCC patients with HCV increased in elderly persons, including female patients. Background liver function was significantly better for female patients (P < 0.001). In both genders, the duration between blood transfusion and diagnosis of HCC was significantly shorter when the patients received blood transfusion at an older age (P < 0.001). In habitual drinkers, the average age at first diagnosis of HCC was significantly younger (P < 0.001), and duration to development of HCC significantly shorter (P < 0.05). The percentage of atomic bomb survivors among HCV-positive HCC patients was significantly higher than that among HCV-negative HCC patients (P < 0.05).

CONCLUSIONS

Patients with HCV might exhibit slow disease progression and develop HCC finally with aging regardless of gender. Patients of advanced age with HCV, even female patients, should therefore be closely followed.

Property of metallothionein as a Zn pool differs depending on the induced condition of metallothionein

Metallothionein (MT) is a low-molecular-weight, cysteine-rich, heavy metal-binding protein with several putative physiological functions as a radical scavenger and a regulator of metabolism of Zn. Although the induction of hepatic MT by a wide range of stressors is a well-known phenomenon, little is known about the role of MT in stressful situations. Since MT regulates Zn metabolism, we investigated the differences between affinities of MT for Zn in various stressful conditions in this study. Divalent cadmium ions are capable of displacement of Zn from MT in vitro. Therefore, we assayed the binding of Zn to MT induced by various stimuli using in vivo administration of Cd. MT was induced by paraquat (PQ), a reactive oxygen generator, fasting stress and restraint stress. Apo-MT induced by them bound to Zn in vivo. Zn, which bound to MT induced by PQ, was displaced by the administration of Cd. However, Zn that had bound to MT induced by fasting stress and restraint stress was not displaced by Cd. Moreover, we assessed the in vivo affinity of Zn to MT induced by fasting stress under the condition of subchronic Cd exposure. Cd was administered to mice by subcutaneously implanted Alzet osmotic minipumps, which released constant amounts of Cd over a 14-day period. After 4 days, mice were fasted for 24 h and hepatic MT was examined. Interestingly, it was found that Zn had displaced Cd bound to MT. These findings indicate that the affinity of MT for Zn differs depending on the stimulus by which MT was induced. This is the first report on differences in the properties of MT depending on the stimulus used to induce MT.

Change in cytoskeletal phenotype and extracellular matrix production of muscularis mucosae during early invasive colorectal adenocarcinoma

Bundles of eosinophilic spindle cells are often found in histological preparations of the stroma of invasive colorectal adenocarcinomas. To clarify their significance, especially during the early invasive phase, we histologically and immunohistochemically studied 33 submucosally invasive colorectal adenocarcinomas in terms of their relationship with the muscularis mucosa, their cytoskeletal phenotype, and their production of extracellular matrix (ECM). Histological continuity between bundles of eosinophilic spindle cells and the muscularis mucosa was identified in 19 out of 33 adenocarcinomas (57.6%). With respect to their cytoskeletal phenotypes, the expression of alpha-smooth muscle actin (alpha-SMA) did not differ between the muscularis mucosa and the eosinophilic spindle cells, whereas the expression of desmin and high molecular weight caldesmon (h-CD) of the eosinophilic spindle cells was decreased compared with that of the muscularis mucosa (p<0.05). Definitive type I procollagen (procollagen I) expression was identified, at least in part, in 16 out of 20 (80%) areas of the eosinophilic spindle cells that were continuous with the muscularis mucosa, and in 26 out of 29 (89.7%) areas of the eosinophilic spindle cells that were not. These findings suggest that the muscularis mucosa is the origin of the eosinophilic spindle cells, that they undergo phenotypic changes separately from the smooth muscle, that is, myofibroblastic changes, and that they contribute to carcinomatous stroma formation through production of an ECM component. These findings should be taken into consideration when determining the level of submucosal invasion by colorectal adenocarcinomas.

Annexin II overexpression correlates with stromal tenascin-C overexpression: a prognostic marker in colorectal carcinoma

BACKGROUND

Overexpression of annexin II, a calcium-dependent phospholipid-binding protein, has been reported in various carcinomas. One of its ligands is tenascin-C, an extracellular matrix glycoprotein with predominantly antiadhesive qualities that also has been reported to be a prognostic marker for several carcinomas. In the current study, the authors investigated the correlation between the overexpression of annexin II and tenascin-C in colorectal carcinoma.

METHODS

Western blot analysis of annexin II expression was examined in four human colorectal carcinoma cell lines. Using immunohistochemical methods, the authors also examined expression of annexin II and tenascin-C in 105 primary colorectal carcinoma cases.

RESULTS

Although annexin II was expressed in human colon carcinoma cell lines, there was no apparent correlation between its expression level and the metastatic potential of these cell lines. The authors observed overexpression of annexin II and tenascin-C proteins in 29.5% and 49.5%, respectively, of colorectal carcinoma cases. Overexpression of annexin II was found to be correlated significantly with histologic type, tumor size, depth of invasion, and pTNM stage, whereas tenascin-C overexpression was noted to be correlated significantly with histologic type, depth of invasion, lymphatic invasion, venous invasion, lymph node metastasis, and pTNM stage. Expression of annexin II was shown to be correlated significantly with that of tenascin-C. Multivariate analysis demonstrated that annexin II and tenascin-C cooverexpression was an independent factor of poor prognosis in patients with colorectal carcinoma.

CONCLUSIONS

The data from the current study suggest that both annexin II and tenascin-C are overexpressed in advanced colorectal carcinoma and that they may be related to the progression and metastatic spread of colorectal carcinoma.

Effects of stereotactic radiosurgery on metastatic brain tumors of various histopathologies

Although reports have been published describing clinical results in a large series of patients with metastatic brain tumors treated by stereotactic radiosurgery (SRS), clinical neuropathological correlation has rarely been available. The present paper describes three autopsy cases and one surgical case treated with linear accelerator based radiosurgery. The cases comprised a lung cancer, a rectal cancer, an osteosarcoma, and a malignant melanoma. Histological sections of each tumor were analyzed by light microscopy based on the Ohosi and Shimosato's histopathological classification of the effects of radiation therapy. In three cases (pulmonary squamous cell carcinoma, rectal adenocarcinoma and osteosarcoma), a large area of the tumors consisted of coagulation necrosis and non-viable tumor cells, while coagulation necrosis and non-viable tumor cells comprised a very small part of the malignant melanoma. Histopathological type of the metastatic brain tumor may be one of the factors influencing outcome after SRS.

Annexin II overexpression correlates with stromal tenascin-C overexpression: a prognostic marker in colorectal carcinoma

BACKGROUND

Overexpression of annexin II, a calcium-dependent phospholipid-binding protein, has been reported in various carcinomas. One of its ligands is tenascin-C, an extracellular matrix glycoprotein with predominantly antiadhesive qualities that also has been reported to be a prognostic marker for several carcinomas. In the current study, the authors investigated the correlation between the overexpression of annexin II and tenascin-C in colorectal carcinoma.

METHODS

Western blot analysis of annexin II expression was examined in four human colorectal carcinoma cell lines. Using immunohistochemical methods, the authors also examined expression of annexin II and tenascin-C in 105 primary colorectal carcinoma cases.

RESULTS

Although annexin II was expressed in human colon carcinoma cell lines, there was no apparent correlation between its expression level and the metastatic potential of these cell lines. The authors observed overexpression of annexin II and tenascin-C proteins in 29.5% and 49.5%, respectively, of colorectal carcinoma cases. Overexpression of annexin II was found to be correlated significantly with histologic type, tumor size, depth of invasion, and pTNM stage, whereas tenascin-C overexpression was noted to be correlated significantly with histologic type, depth of invasion, lymphatic invasion, venous invasion, lymph node metastasis, and pTNM stage. Expression of annexin II was shown to be correlated significantly with that of tenascin-C. Multivariate analysis demonstrated that annexin II and tenascin-C cooverexpression was an independent factor of poor prognosis in patients with colorectal carcinoma.

CONCLUSIONS

The data from the current study suggest that both annexin II and tenascin-C are overexpressed in advanced colorectal carcinoma and that they may be related to the progression and metastatic spread of colorectal carcinoma.

Basilar artery vasculitis secondary to sphenoid sinusitis--case report

A 35-year-old male presented with basilar artery vasculitis secondary to sphenoid sinusitis manifesting as rapidly deteriorating symptoms including consciousness disturbance and right hemiparesis. Computed tomography (CT) on admission showed sphenoid sinusitis without intracranial lesion. Emergency angiography demonstrated basilar artery stenosis. The neurological deterioration was considered to be caused by ischemia of the perforating arteries branching from the stenotic portion of the basilar artery. The patient was treated with urokinase infusion through a microcatheter just proximal to the stenosis 3 hours after the onset of the symptoms. His consciousness level and right hemiparesis markedly improved immediately after the procedure. Magnetic resonance (MR) imaging on day 5 revealed that extension of the sphenoid sinusitis into the prepontine cistern had formed an abscess which was attached to the clivus. The basilar artery was embedded in the abscess at the angiographic stenosis. Cerebrospinal fluid (CSF) analysis showed white blood cell count of 601/mm3 with 82% neutrophils, 89.2 mg/dl protein, and 31 mg/dl glucose. No causative organism in the CSF could be identified by smear or culture. Early MR imaging and CSF examination are recommended when patients present with both ischemic symptoms involving the basilar artery and opacification of the sphenoid sinus on CT to identify basilar artery vasculitis secondary to sphenoid sinusitis.

Crystal structure of negative cofactor 2 recognizing the TBP-DNA transcription complex

The X-ray structure of a ternary complex of Negative Cofactor 2 (NC2), the TATA box binding protein (TBP), and DNA has been determined at 2.6 A resolution. The N termini of NC2 alpha and beta resemble histones H2A and H2B, respectively, and form a heterodimer that binds to the bent DNA double helix on the underside of the preformed TBP-DNA complex via electrostatic interactions. NC2beta contributes to inhibition of TATA-dependent transcription through interactions of its C-terminal alpha helix with a conserved hydrophobic feature on the upper surface of TBP, which in turn positions the penultimate alpha helix of NC2beta to block recognition of the TBP-DNA complex by transcription factor IIB. Further regulatory implications of the NC2 heterodimer structure are discussed.

Long-term prognosis of patients undergoing transcatheter arterial chemoembolization for unresectable hepatocellular carcinoma: comparison of cisplatin lipiodol suspension and doxorubicin hydrochloride emulsion

PURPOSE

To evaluate long-term prognosis of transcatheter arterial chemoembolization (TACE) with use of cisplatin (CDDP) lipiodol (LPD) suspension (CDDP/LPD) compared with that with use of doxorubicin hydrochloride (ADM) LPD emulsion (ADM/LPD) in patients with unresectable hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

One hundred eight patients were treated with use of CDDP/LPD and 26 were treated with use of ADM/LPD. Survival rates and frequency of side effects and complications in the CDDP/LPD group were compared with those in the ADM/LPD group.

RESULTS

CDDP/LPD was given at a dose of 15-70 mg (mean dose, 41 mg), whereas ADM/LPD was given at a dose of 20-100 mg (mean dose, 57 mg) throughout the study period. The survival rates in the CDDP/LPD group were 81% at 1 year, 41% at 3 years, 19% at 5 years, and 13% at 7 years, whereas those in the ADM/LPD group were 67% at 1 year, 18% at 3 years, and 0% at 5 years. The CDDP/LPD group showed significantly better survival than the ADM/LPD group (P <.05). In the CDDP/LPD group, there was a significant prolongation of survival in patients with monofocal HCC (P <.05) and patients with HCC assessed as an almost complete LPD accumulation (P <.05). There were no significant differences in survival rates in the ADM/LPD group according to tumor size and number of tumors. Hepatic failure was observed in 8% of all procedures and was not different between the two therapeutic groups. Renal dysfunction was observed in 2% of all treatments involving CDDP/LPD, and it resolved spontaneously with appropriate medications.

CONCLUSIONS

TACE with use of low-dose CDDP was efficacious for unresectable HCC and had few complications. TACE with use of CDDP may contribute to prolongation of the life span of patients with HCC versus TACE with use of ADM.

Tumor-specific chemo-radio-gene therapy for colorectal cancer cells using adenovirus vector expressing the cytosine deaminase gene

We studied the effect of suicide gene therapy using an adenovirus vector expressing the cytosine deaminase (CD) gene combined with irradiation therapy (chemo-radio-gene therapy) for human colorectal cancer cells. Since serum CEA levels are elevated in patients with some malignant tumors including colorectal cancer, we applied the CEA promoter to chemo-radio-gene therapy, expecting tumor-specific expression of the CD gene. In in vitro study, we succeeded in selective expression of the target CD gene and growth inhibition in only CEA-producing tumor cells; Further the inhibitory effect was enhanced by combination with radiation therapy in an irradiation dose-dependent manner. In addition, in in vivo study, a significant growth inhibition was observed in chemo-radio-gene therapy in comparison with radiation therapy alone or suicide gene therapy alone. Thus, we suggest that tumor-specific chemo-radio-gene therapy may be a useful strategy for human colorectal cancer.

Enhanced late components of AEFs associated with the temporal lobe lesions

We recorded auditory evoked magnetic fields (AEFs) by presenting pure tone bursts once every 4000 ms in 11 patients with a brain lesion in or in the vicinity of the auditory cortex. AEFs on the damaged side revealed several enhanced deflections in late-latency AEFs (slow AEFs), peaking at approximately 320 (DI), 1030 (D2) and 1600 (D3) ms post-stimulus in eight patients. All the dipoles of slow AEFs were concentrated in the superior temporal regions which were not involved by brain lesions. D1, D2 and D3 dipoles were uniformly upward, downward and upward, respectively. The dipole moment varied from 12 to 122 nAm and had no consistent relationship with latency. This is the first report describing slow AEFs in cases with temporal lobe lesions.

A combined study of tumor-related brain lesions using MEG and proton MR spectroscopic imaging

The purpose of this study is to localize, in cases of brain tumors, pathological magnetic brain activities and to analyze metabolic alterations in functionally abnormal lesions using magnetoencephalography (MEG) and proton magnetic resonance spectroscopic imaging (1H MRSI). The study focused on 10 healthy volunteers and seven patients with common brain tumors, namely astrocytic tumor and meningioma. In spontaneous MEG, the pathological brain activities (slow, fast waves and spikes) were localized using a single equivalent dipole model. After the results of MEG and 1H MRSI were superimposed onto the corresponding MR images, the signal intensities of spectroscopically visible metabolites were analyzed in the regions where the dipoles of the pathological activities were concentrated. Increased slow wave activity was observed in four cases and fast wave or spike activity was significantly increased in one case. These pathological activities were localized in surrounding regions of the bulk of tumors, where mild reduction of N-acetyl aspartate (NAA) and slight accumulation of lactate (Lac) consistently existed. Preserved cortical areas, which are indicated by residual NAA, might be able to generate pathological magnetic activities under lactic acidosis. Such areas could be understood as a border zone between normal and seriously damaged brain tissue by tumors or associated brain edema. This combined technique with the different modalities gives insight into functional as well as metabolic aspects of pathological brain conditions.

Reversible brain dysfunction in MELAS: MEG, and (1)H MRS analysis

This case report describes a follow up investigation of a patient with impaired word discrimination due to mitochondrial encephalopathy with lactic acidosis and stroke-like syndrome (MELAS) using proton magnetic resonance spectroscopy ((1)H MRS) and auditory evoked magnetic fields (AEFs). The initial (1)H MRS showed no N-acetyl aspartate (NAA) and marked accumulation of lactate (Lac) in the stroke-like lesion of MELAS, which was silent in neural activity according to AEFs. The follow up investigations, however, demonstrated that NAA reappeared, that the formerly increased Lac signal was significantly reduced, and that the magnitude of AEFs of the lesion was markedly increased. Metabolic and functional changes in (1)H MRS and AEFs reflected the neurological recovery very well. The stroke-like lesion was shown, using AEFs and (1)H MRS, to be able to function properly, although brain tissue of the lesion initially had severe damage due to mitochondrial dysfunction.

Early bond strength and durability of bond between a ceramic material and chemically-cured or dual-cured resin luting agent

PURPOSE

To evaluate the influence of the different polymerization types of two chemically-cured (Panavia 21 and Super-Bond C&B) and three dual-cured (Panavia Fluoro Cement, Clapearl DC, and Vita Cerec Duo Cement) resin luting agents on the early bond strengths and durability of bond to a Cerec 2 ceramic material.

MATERIALS AND METHODS

The Cerec 2 ceramic specimens were prepared with No. 600 silicon carbide paper and their surfaces were etched with phosphoric acid gel, and applied with silane coupling agent. Two sizes of specimens were then bonded together with each of the five luting agents. Shear bond tests were performed 10 mins or 20 mins after preparing specimens, storage in water at 37 degrees C for 24 hrs, and/or 20,000 thermocycles between 4 degrees C and 60 degrees C water baths.

RESULTS

The specimens bonded with one of the three dual-cured resin luting agents showed almost the same shear bond strengths for all four storage conditions. However, two chemically-cured resin luting agents exhibited much lower shear bond strengths at 10- and 20-min intervals than at 0 and 20,000 thermocycles. Three dual-cured resin luting agents showed significantly higher bond strengths than two chemically-cured resin luting agents at 10- and 20-min intervals.

Crystal structure of the C-terminal domain of the RAP74 subunit of human transcription factor IIF

The x-ray structure of a C-terminal fragment of the RAP74 subunit of human transcription factor (TF) IIF has been determined at 1.02-A resolution. The alpha/beta structure is strikingly similar to the globular domain of linker histone H5 and the DNA-binding domain of hepatocyte nuclear factor 3gamma (HNF-3gamma), making it a winged-helix protein. The surface electrostatic properties of this compact domain differ significantly from those of bona fide winged-helix transcription factors (HNF-3gamma and RFX1) and from the winged-helix domains found within the RAP30 subunit of TFIIF and the beta subunit of TFIIE. RAP74 has been shown to interact with the TFIIF-associated C-terminal domain phosphatase FCP1, and a putative phosphatase binding site has been identified within the RAP74 winged-helix domain.

Synthesis and photochromism of spirobenzopyran derivatives bearing an oxymethylcrown ether moiety: metal ion-induced switching between positive and negative photochromisms

Spirobenzopyran derivatives carrying an oxymethylcrown ether moiety were synthesized, and their photochromism was studied in the presence of various metal ions in acetonitrile. The metal ion complexing ability of the crown ether moiety in crowned spirobenzopyrans affects both thermal isomerization and photoisomerization of their spirobenzopyran moiety to a great extent. When the interaction of the crown ether moiety with a metal ion was strong enough to cause thermal isomerization of the spirobenzopyran moiety to its corresponding merocyanine form and to suppress UV-induced isomerization to the merocyanine form, a negative photochromism appears. On the other hand, a relatively weak interaction of the crown ether moiety with a metal ion affords a positive photochromism. This phenomenon enables us to switch the photochromic behavior between positive and negative photochromisms.

Scleroderma associated with anemia and thrombocytopenia that responded well to cyclosporin

A 55-year-old woman came to our hospital because of cutaneous sclerosis of the limbs in September 1996, and was diagnosed with scleroderma based on a skin biopsy. In August 1997, the cutaneous sclerosis became progressive (hemoglobin level, 4.3 g/dl; platelet count, 7 x 10(9)/l). The laboratory results were positive for the direct Coombs test, bone marrow aspiration showed a dry tap, and the bone marrow biopsy showed marked fatty marrow. Indium-111 bone marrow scintigraphy showed a markedly decreasing uptake. These findings indicated bone marrow hypoplasia associated with hemolytic anemia. After prednisolone therapy (60 mg) was initiated, the direct Coombs test became negative but the blood cell count did not increase. Then, 300 mg of cyclosporin was initiated and anemia and thrombocytopenia improved. The cyclosporin dosage was gradually decreased and the patient's hematological condition was good, although the cutaneous sclerosis changed only a little. This is a rare and interesting case of a patient with scleroderma associated with bone marrow insufficiency and hemolysis who responded well to cyclosporin.

Annexin II overexpression is correlated with poor prognosis in human gastric carcinoma

Annexins belong to a family of the calcium-dependent phospholipid binding proteins. They are also substrates of receptor tyrosine kinases. Overexpression of Annexin II, which has been reported in various carcinomas, is thought to be associated with cell proliferation, differentiation and cell-cell adhesion in the pathogenesis of carcinoma, but the functions of Annexins have not been fully elucidated. In this study, we investigated the role of Annexin II (p36) and its relationship with c-erbB-2 overexpression in gastric carcinoma. We studied Annexin II expression using Western blot analysis in 8 human gastric carcinoma cell lines and expression of Annexin II and c-erbB-2 using, immunohistochemistry in 153 primary gastric carcinomas. Western blot revealed that Annexin II was expressed in 8 human gastric carcinoma cell lines. It was more strongly expressed in the cell membrane than in the cytoplasm of tumor cells in primary gastric carcinoma tissues. Thirty-three percent of all cases were immunopositive for Annexin II, overexpression of which was more frequent in differentiated type (p = 0.0009), lymph node, metastasis (p = 0.0147) and venous invasion (p = 0.0092). Annexin II and c-erbB-2 overexpression were significantly correlated p = 0.0002) and patients with Annexin II had poorer prognoses (p = 0.0066). Multivariate analysis showed that immunopositivity of both Annexin II and c-erbB-2 was an independent and poor prognostic factor (p = 0.0037). In conclusion, Annexin II was overexpressed in advanced gastric carcinomas and it could contribute to the progression of gastric carcinoma.

Effects of two silane coupling agents, a bonding agent, and thermal cycling on the bond strength of a CAD/CAM composite material cemented with two resin luting agents

STATEMENT OF PROBLEM

Surface treatment of CAD/CAM-generated composite material is important for a strong bond of resin luting agents to composite material. Purpose. This study evaluated the shear bond strengths of 2 dual-cured resin luting agents to a CAD/CAM composite material and the effect of silane coupling agent and bonding resin on the bond strength.

MATERIAL AND METHODS

Rectangular- and disk-shaped CAD/CAM composite materials were untreated or treated with 1 of the 2 silane coupling agents or bonding resin and then cemented together with 1 of the 2 dual-cured resin luting agents. Half of the specimens were stored in water at 37 degrees C for 24 hours, the other half thermocycled 50,000 times before shear bond strength testing. Shear bond strengths were measured with a servohydraulic mechanical testing machine, and results were analyzed with 2-way analysis of variance.

RESULTS

Surface treatment by silane coupling agent improved the shear bond strength when compared with nontreatment. Specimens treated with bonding resin showed significantly greater shear bond strength than the untreated groups. However, all specimens had the same adhesive failures at the composite-luting agent interface as untreated groups. When the CAD/CAM composite material was treated with 1 of the 2 silane coupling agents, no significant differences in bond strength were noted between water storage alone and after 50,000 thermocycles. For the 2 groups treated with bonding resin or silane coupling agent and cemented with 1 of the 2 dual-cured resin luting agents, there were significant increases in bond strength after 50,000 thermocycles, compared with specimens that were not subjected to thermal cycling. On the other hand, for the 2 untreated groups, there were significant decreases in bond strength after thermocycling. After 50,000 thermocycles, all specimens treated with silane coupling agent and then cemented with 1 of the 2 resin luting agents showed cohesive failures within the composite material.

CONCLUSION

The application of a silane coupling agent to the CAD/CAM composite surface provided the highest bond strength between the resin luting agent and composite after long-term thermal cycling.

Effect of three adhesive primers on the bond strengths of four light-activated opaque resins to noble alloy

The effect of commercial adhesive primers for noble metals on the bond strength of light-activated opaque resin has not been determined. This study evaluated the effect of three adhesive primers on the shear bond strengths of each of the four light-activated opaque resins to silver--palladium--copper--gold (Ag--Pd--Cu--Au) alloy. The adhesive primers Alloy Primer (AP), Metal Primer II (MPII) and Metaltite(MT) were used. Four commercial light-activated opaque resins (Axis (AX), Cesead II (CEII), Dentacolor(DE) and Solidex (SO) were used to bond a light-activated resin-veneered composite to Ag--Pd--Cu--Au alloy. The specimens were stored in water at 37 degrees C for 24 h and then immersed alternatively in water baths at 4 and 60 degrees C for 1 min each for up to 20,000 thermal cycles before shear mode testing at a cross-head speed of 0.5 mm min(-1). All the primers examined improved the shear bond strength between opaque resin and Ag--Pd--Cu--Au alloy compared with non-primed specimens prior to thermal cycling. After 20,000 thermal cycles, the bond strengths of combined use of AP and DE and that of MT and each of AX, CE or DE were significantly greater than any other groups. Significant difference was observed between the bond strengths at thermal cycles 0 and 20,000, with the combined use of MT and DE. With the combination of appropriate adhesive metal primers and light-activated opaque resins, complicated surface preparations of metal frameworks of resin-veneered prostheses that are composed of casting Ag-Pd-Cu-Au alloy may be negligible.

Effect of three adhesive primers for a noble metal on the shear bond strengths of three resin cements

The purpose of this study was to evaluate the durability and shear bond strengths of the different combinations of three adhesive primers and three resin cements to a silver-palladium-copper-gold (Ag-Pd-Cu-Au) alloy. The adhesive primers Alloy Primer (AP), Metal PrimerII (MPII) and Metaltite (MT), and the resin cements BistiteII (BRII), Panavia Fluoro Cement (PFC) and Super-Bond C&B (SB) were used. Two sizes of casting alloy disks were either non-primed or primed and cemented with each of the three resin cements. The specimens were stored in a 37 degrees C water bath for 24 h and then immersed alternately in 4 and 60 degrees C water baths for 1 min each for up to 100,000 thermal cycles. Shear mode testing at a crosshead speed of 0.5 mm/min was then performed. The application of MPII or MT was effective for improving the shear bond strength between each of the three resin cements and the Ag-Pd-Cu-Au alloy compared with non-primed specimens. However, when primed with MPII or MT and cemented with SB, the bond strength at 100,000 thermal cycles was significantly lower than that at thermal cycle 0. When primed with AP, the specimens cemented with BRII or PFC showed lower bond strength than non-primed specimens and failed at the metal-resin cement interface at 100,000 thermal cycles. On the other hand, AP was effective in enhancing the shear bond strength of SB to the Ag-Pd-Cu-Au alloy. The five combined uses of an adhesive metal primer and resin cement (combinations of MPII or MT and BRII or PFC and AP and SB) are applicable to the cementation of prosthodontic restorations without complicated surface modification of the noble alloy.

Phenotypic change of muscularis mucosae in early invasive colorectal adenocarcinoma

BACKGROUND

Invasive colorectal adenocarcinomas have bundles of eosinophilic spindle cells, which are regarded as myofibroblasts, in their desmoplastic stroma, some of which are continuous with the muscularis mucosa.

AIM

To investigate the relation between the eosinophilic spindle cells and the muscularis mucosa based on their cytoskeletal phenotypes in early invasive colorectal adenocarcinoma.

METHODS

Formalin fixed, paraffin wax embedded tissues of 17 early invasive colorectal adenocarcinomas were immunostained for alpha-smooth muscle actin (alpha-SMA), desmin, and vimentin.

RESULTS

The phenotype of the muscularis mucosa was alpha-SMA positive, desmin positive, and vimentin weakly positive, whereas the eosinophilic spindle cells showed a decreased degree of immunoreactivity for alpha-SMA and desmin in particular, and an increased degree of immunoreactivity for vimentin. The degree of phenotypic difference between the muscularis mucosa and the eosinophilic spindle cells was greater in the eosinophilic spindle cells in the centre of the invasive area that were not continuous with the muscularis mucosa than in the eosinophilic spindle cells continuous with the muscularis mucosa.

CONCLUSIONS

These findings suggest that the smooth muscle cells of the muscularis mucosa change their phenotype to become eosinophilic spindle cells, namely myofibroblasts, in the early invasive area of colorectal adenocarcinoma.

In vivo administration of mycobacterial cord factor (Trehalose 6, 6'-dimycolate) can induce lung and liver granulomas and thymic atrophy in rabbits

Trehalose 6,6'-dimycolate (TDM) is a cell surface molecule of Mycobacterium tuberculosis. TDM induced a loss of body weight and prominent granulomas in the liver and lungs by the intravenous injection of TDM into rabbits. TDM also induced atrophy of the thymus and spleen due to apoptosis. By contrast, sulfolipid (2,3,6, 6'-tetraacyl trehalose 2'-sulfate) induced neither toxicity, nor granuloma formation, nor atrophy of the thymus and spleen. In rabbits the histopathological changes were more dramatic than in mice. The rabbit model may be more sensitive and may provide more information on the beneficial or pathological effects of TDM.

Effect of thione primers on bonding of noble metal alloys with an adhesive resin

OBJECTIVES

The purpose of the current study was to evaluate the effects of two metal conditioners on the bond durability of an adhesive resin joined to noble metal alloys by comparing pre- and post-thermocycling bond strengths.

METHODS

Two different sizes of disk specimens (10 and 8mm in diameter by 2.5mm thickness) were prepared from silver-indium (Ag-In-Zn, Salivan), silver-palladium-copper-gold (Ag-Pd-Cu, Castwell M.C.12), metal-ceramic gold (Au-Pt-Pd, Degudent-Universal), metal-ceramic palladium (Pd-Ga-Co, PTM 88), type IV gold (type IV, Casting Gold) alloys, and pure silver (pure Ag). The specimens were air-abraded with 50-microm grain sized alumina, conditioned either with a thiouracil primer (Metaltite) or with a thione-phosphate primer (Alloy Primer), then bonded with an adhesive resin (Super-Bond Opaque). Shear bond strengths were determined both before and after repeated thermocycling (4 degrees C and 60 degrees C, 1min each, 100, 000cycles). The results were compared by analysis of variance and post-hoc multiple comparison intervals.

RESULTS

The average post-thermocycling bond strengths in MPa (n=8) generated with the thiouracil primed and thione-phosphate primed groups, respectively, were: 3.4 and 5.8 for the Ag-In-Zn alloy, 40.4 and 37.7 for the Ag-Pd-Cu alloy, 26.4 and 33.5 for the Au-Pt-Pd alloy, 27.4 and 36.6 for the Pd-Ga-Co alloy, 40.2 and 40.3 for the type IV alloy, and 37.3 and 32.4 for the pure Ag. The Ag-In-Zn alloy exhibited significantly lower bond strength than the other alloys, whereas the Ag-Pd-Cu and type IV alloys exhibited the greatest magnitude of bond strength for both primers (p<0.05).

CONCLUSIONS

It can be concluded that the combined use of either of the two thione primers and the adhesive resin is effective for bonding the metal/alloys examined, with the exception of the Ag-In-Zn alloy.

Recombinant carboxyltransferase responsive to redox of pea plastidic acetyl-CoA carboxylase

Acetyl-CoA carboxylase regulates the rate of fatty acid synthesis. This enzyme in plants is localized in plastids and is believed to be composed of biotin carboxyl carrier protein, biotin carboxylase, and carboxyltransferase made up of alpha and beta polypeptides, although the enzyme has not been purified yet. Accumulated evidence shows that pea plastidic acetyl-CoA carboxylase is activated by light and the activation is caused by light-dependent reduction of carboxyltransferase, but not of biotin carboxylase, via a redox cascade. To understand the reductive activation of carboxyltransferase at the molecular level here, we obtained the active enzyme composed of decahistidine-tagged (His tag) alpha and beta polypeptides through the expression of the pea plastidic carboxyltransferase gene in Escherichia coli. Gel filtration showed that the molecular size of the recombinant carboxyltransferase is in agreement with that of partially purified carboxyltransferase from pea chloroplasts. The catalytic activity of the recombinant enzyme was similar to that of native carboxyltransferase. These results indicate that the molecular structure and conformation of recombinant carboxyltransferase resemble those of its native counterpart and that native carboxyltransferase is indeed composed of alpha and beta polypeptides. This recombinant enzyme was activated by dithiothreitol, a known reductant of S-S bonds, with a profile similar to that of its native counterpart. The recombinant enzyme was activated by reduced thioredoxin-f, a signal transducer of redox potential in chloroplasts under irradiation. Thus, this enzyme was redox-regulated, like that of the native carboxyltransferase.

Thin sol-gel-derived silica coatings on dental pure titanium casting

The sol-gel dipping process, in which liquid silicon alkoxide is transformed into a solid silicon-oxygen network, can produce a thin film coating of silica (SiO(2)). The features of this method are high homogeneity and purity of the thin SiO(2) film and a low sinter temperature, which are important in the preparation of coating films that can protect metallic ion release from the metal substrate and prevent attachment of dental plaque. We evaluated the surface properties of dental pure titanium casting coated with a thin SiO(2) or SiO(2)/F-hybrid film by the sol-gel dipping process. The metal specimens were pretreated by dipping in isopropylalcohol solution containing 10 wt% 3-aminopropyl trimethoxysilane and treated by dipping in the silica precursor solution for 5 min, withdrawal at a speed of 2 mm/min, air-drying for 20 min at room temperature, heating at 120 degrees C for 20 min, and then storing at room temperature. Both SiO(2) and SiO(2)/F films bonded strongly (above 55 MPa) to pure titanium substrate by a tensile test. SiO(2(-)) and SiO(2)/F-coated specimens immersed in 1 wt% of lactic acid solution for two weeks showed significantly less release of titanium ions (30. 5 ppb/cm(2) and 9.5 ppb/cm(2), respectively) from the substrate than noncoated specimens (235.2 ppb/cm(2)). Hydrophobilization of SiO(2(-)) and SiO(2)/F-coated surfaces resulted in significant increases of contact angle of water (81.6 degrees and 105.7 degrees, respectively) compared with noncoated metal specimens (62.1 degrees ). The formation of both thin SiO(2) and SiO(2)/F-hybrid films by the sol-gel dipping process on the surface of dental pure titanium casting may be useful clinically in enhancing the bond strength of dental resin cements to titanium, preventing titanium ions release from the substrate, and reducing the accumulation of dental plaque attaching to intraoral dental restorations.

[Usefulness of temporal subtraction images of chest computed radiography for detection of metastatic pulmonary nodules]

Temporal subtraction is a technique by which a previous chest radiograph is subtracted from a current radiograph in order to enhance interval changes. Our purpose in this study was to evaluate the usefulness of temporal subtraction for the detection of metastatic pulmonary nodules. We examined 19 cases of metastatic nodules less than 15 mm in diameter (8.4 mm on average). Temporal subtraction images were created based on the matching of local lung areas in pairs of chest radiographs. By using the subtraction images, the detectability of nodules was clearly improved in 5 cases and moderately improved in 8 cases; there was no improvement in 6 cases. The subtraction images were especially useful for nodules superimposed over normal structures, such as rib, mediastinum, and diaphragm, as well as for small nodules. In 6 of the 19 cases, the nodules had been missed clinically; however, the temporal subtraction images clearly demonstrated half of missed small nodules. Temporal subtraction made it possible to enhance subtle interval changes and helped in detecting small pulmonary metastases. This technique seems promising for augmenting the capabilities of computed radiography of the chest.

Regional cerebral blood flow after status epilepticus

Two patients with status epilepticus due to specific conditions were examined using MRI and stable Xe/CT CBF. [Case 1] A 30-year-old woman developed a grand mal seizure during delivery. She was comatose, and MRI revealed abnormal high intensity areas bilateral basal ganglia, compatible with eclampsia. Regional CBF was decreased in bilateral occipital lobes and right basal ganglia. Six days after onset. Regional gray matter flow was increased, especially in the thalami and basal ganglia. [Case 2] The patient is a 31-year-old male diagnosed with temporal lobe epilepsy since 10 years. At the onset, he had a prolonged right hemiconvulsion followed by generalized tonic-clonic convulsion. MRI 13 days after onset showed left hemispheric edematous swelling of gray matter. Stable Xe/CT 3 weeks after onset demonstrated increased cortical CBF corresponding to edematous area. The results suggested that regional CBF decreased immediately after status epilepticus and then increased for 1-3 weeks in the interictal period. We speculate that the energy debt incurred during prolonged seizure causes relative ischemic condition in the neurons, with the increase in CBF resulting from accelerated energy production for a long period.

Anatomical and functional imaging of the auditory cortex in awake mustached bats using magnetic resonance technology

The auditory cortex of mustached bats, Pteronotus parnellii, has been studied extensively using neuroanatomical tract-tracing and electrophysiological techniques to elucidate the functional organization and neural mechanisms important for auditory processing. While these techniques have identified several cortical maps involved in processing auditory information, there has been no direct observation of the dynamics of simultaneous activation of several discrete areas. We applied magnetic resonance (MR) imaging techniques for visualizing brain structures in awake bats using a 7-Tesla magnet system; we also investigated functional MR imaging by measuring changes in stimulus-correlated blood oxygenation levels to detect cortical areas exhibiting evoked neural activity. High resolution (100 microm) anatomical images were successfully acquired without any motion artifacts. It was possible to reconstruct the whole brain image and analyze brain surface structures with three dimensional (3D) MR imaging data. These data provide detailed morphometric measurements that will allow localization of stimulus specific neural activity patterns using modified functional magnetic-resonance-imaging (fMRI) protocols. Motion artifacts is the primary disadvantage of using awake bats; our study shows that fMRI of a bat's brain is feasible and may prove to be an important advancement for a further understanding of auditory processing in this species.Themes: Sensory systems, Neural basis of behavior.

A combined study of tumor-related brain lesions by using magnetoencephalography and 1H magnetic resonance spectroscopic imaging. Technical note

The purpose of this study was to localize pathological magnetic brain activities and to analyze metabolic alterations in functionally abnormal lesions by using magnetoencephalography (MEG) and (1)H magnetic resonance (MR) spectroscopy in patients with brain tumors. The authors studied 10 healthy volunteers and seven patients who harbored common brain tumors, namely astrocytic tumors and meningioma. In spontaneous MEG the pathological brain activities (slow waves, fast waves, and spikes) were localized using a single equivalent dipole model. After the results of MEG and (1)H MR spectroscopy were superimposed onto the corresponding MR images, the signal intensities of spectroscopically visible metabolites were analyzed in the regions in which the dipoles of the pathological activities were concentrated. Increased slow-wave activity was observed in four cases, and fast-wave or spike activity was significantly increased in one case each, respectively. These pathological activities were localized at almost the same cortical areas adjacent to the bulk of tumors, where mild reduction of N-acetyl aspartate (NAA) and slight accumulation of lactate consistently existed. Preserved and metabolically active cortical areas, which are indicated by residual NAA, might be able to generate pathological magnetic activities under lactic acidosis. Such an area could be understood as a border zone between normal brain tissue and brain tissue that has been seriously damaged by tumors or associated edema, which should be intensively treated. This combination of imaging techniques gives insight into functional as well as metabolic aspects of pathological brain conditions.

Silica coatings formed on noble dental casting alloy by the sol-gel dipping process

The sol-gel dipping process, in which liquid silicon alkoxide is transformed into the solid silicon-oxygen network, can produce a thin film coating of silica (SiO2). The features of this method are high homogeneity and purity of the thin SiO2 film and a low sinter temperature, which are important in preparation of coating films that can protect from metallic ion release from the metal substrate and prevent attachment of dental plaque. We evaluated the surface characteristics of the dental casting silver-palladium-copper-gold (Ag-Pd-Cu-Au) alloy coated with a thin SiO2 film by the sol-gel dipping process. The SiO2 film bonded strongly (over 40 MPa) to Ti-implanted Ag-Pd-Cu-Au alloy substrate as demonstrated by a pull test. Hydrophobilization of Ti-implanted/SiO2-coated surfaces resulted in a significant increase of the contact angle of water (80.5 degrees) compared with that of the noncoated alloy specimens (59.3 degrees). Ti-implanted/SiO2-coated specimens showed the release of many fewer metallic ions (192 ppb/cm2) from the substrate than did noncoated specimens (2,089 ppb/cm2). The formation of a thin SiO2 film by the sol-gel dipping process on the surface of Ti-implanted Ag-Pd-Cu-Au alloy after casting clinically may be useful for minimizing the possibilities of the accumulation of dental plaque and metal allergies caused by intraoral metal restorations.

Adhesive primers for bonding cobalt-chromium alloy to resin

This study evaluated the effect of five adhesive primers on the shear bond strength of a self-curing resin to cobalt-chromium (Co-Cr) alloy. The adhesive primers Acryl Bond (AB, Shofu), Cesead Opaque Primer (COP, Kuraray), Metacolor Opaque Bonding Liner (MOBL, Sun-Medical), Metal PrimerII (MPII, GC) and MR. Bond (MRB, Tokuyama) were used. A brass ring which was placed over the casting alloy disk surface non-primed or primed with each primer was filled with the self-curing MMA-PMMA resin. The specimens were stored in water at 37 degrees C for 24 h and then immersed alternately in water baths at 4 C and 60 degrees C for 1 min each for up to 50000 thermal cycles before shear mode testing at a crosshead speed of 0.5 mm/min. All of the primers examined, except MOBL, improved the shear bond strength between the resin and Co-Cr alloy compared with nonprimed specimens prior to thermal cycling. Regardless of which primer was used, the shear bond strength significantly differed between thermal cycles 0 and 50000. However, after 50000 thermal cycles, the bond strengths of resin to Co-Cr alloy primed with COP or MPII were significantly greater than those of specimens primed with AB, MOBL or MRB and non-primed controls. This study indicated that COP and MPII are effective primers to obtain higher bond strength between resin and Co-Cr alloy.

Systemic granulomatous arteritis associated with Epstein-Barr virus infection

A 61-year-old woman initially presented with symptoms and findings reminiscent of infectious mononucleosis, and her illness then took a rapidly fatal course. Autopsy revealed widespread granulomatous arteritis, with multinucleated giant cells but without eosinophils and fibrinoid necrosis, affecting small arteries and arterioles and infiltration of haemophagocytic histiocytes into many organs. In situ hybridization with Epstein-Barr virus (EBV)-specific oligonucleotide probes showed positive signals in the infiltrating immune cells and epithelial and endothelial cells of the affected organs. EBV-associated haemophagocytic syndrome (EBV-AHS) with systemic granulomatous arteritis was diagnosed. From the immunophenotypes of the infiltrating immune cells, a possible role of CD4+ T-cells in the pathogenesis of this haemophagocytic syndrome and granulomatous vasculitis was suggested.

Metal chloride primers for bonding dentine with tri-n-butylborane-initiated luting agents

OBJECTIVES

The bonding of resin to dentine is dependent largely on surface modifications. The purpose of the present study was to test the hypothesis that a role of the metal chlorides used as primers is to initiate polymerization of resin at the resin-dentine interface, thereby affecting bond strength.

METHODS

Nine primers were evaluated, comprising aqueous 2-hydroxyethyl methacrylate (HEMA) solutions containing AICl3, CeCl3, CoCl2, CuCl2, FeCl3, NiCl2, MgCl2, SnCl2 or ZnCl2, respectively. One of the two luting agents (Super-Bond resin) consisted of methyl methacrylate (MMA), 4-methacryloyloxyethyl trimellitate anhydride (4-META) and tri-n-butylborane (TBB) initiator. The other luting agent (MMA-TBB resin) consisted of MMA and TBB without 4-META. Extracted bovine teeth were ground to expose the dentine, etched with an aqueous solution of 10% phosphoric acid, primed, and then bonded with stainless-steel rods; tensile bond strengths were determined after 1-day immersion in water. Data were analysed by ANOVA and Duncan's new multiple range test (P < 0.05).

RESULTS

Four of the metal chlorides (CuCl2, FeCl3, MgCl2 and ZnCl2) enhanced the bond strengths of MMA-TBB resin to dentine. With Super-Bond resin, maximum bond strengths of 15.6 MPa and 19.0 MPa were recorded with primer containing 2.0 x 10(-5) mol g(-1) FeCl3 and 2.0 x 10(-6) mol g(-1) CuCl2, respectively.

CONCLUSIONS

Bonding techniques, combining the use of either cupric primer or ferric primer with 10% phosphoric acid etchant may be suitable for application in seating resin-bonded prostheses with TBB-initiated luting materials.

Application of RT-PCR designed from the sequence of the local SRSV strain to the screening in viral gastroenteritis outbreaks

The Yuri strain of small round structured virus (SRSV) was cloned from a fecal specimen in which virus particles were observed by electron microscopy. The most common RT-PCR protocol in Japan, however, using 35/36 and NV81/NV82/SM82 nested primer pairs, could not detect the SRSV genome in this specimen. Nucleotide and amino acid sequence analysis revealed that the Yuri strain is genetically close to the genotype II of SRSV. A novel procedure using primer sets designed from the nucleotide sequence of the Yuri strain was applied to the screening of 119 stool samples obtained from subjects with sporadic diarrhea and 46 samples obtained during seven foodborne gastroenteritis outbreaks. Using this novel procedure, PCR bands were detected in 44% and 52% of the samples, respectively. These detection rates were approximately twice those obtained with the 35/36 and NV81/NV82/SM82 nested primers. In particular, more than 40% of positive samples could be detected by using only the Yuri primer sets. Furthermore, three improvements were made in the RNA preparation, cDNA synthesis, and amplification steps to save materials and time. The background, or extra bands, in the amplification reaction resulting from DNA in the fecal specimens was completely removed by DNase I treatment just before cDNA synthesis. Random nonamers were used as universal primers in the reverse transcription. No difference in sensitivity or specificity was noted in the final results when either random nonamers or specific primers were used. The use of a preamplification step under low stringent conditions before standard amplification under highly stringent conditions compensated for any mismatched bases in the primers with respect to the target sequences. Thus our novel procedure using Yuri primer sets may be useful for the screening of SRSV in the recent SRSV outbreaks in Japan.

[A case of retroperitoneal malignant lymphoma successfully treated by chemotherapy]

A 71-year-old woman was admitted to our hospital with the complaint of lower abdominal pain. CT scan revealed a huge retroperitoneal mass. On laparotomy the tumor was found to have extensively invaded the retroperitoneum, and an incisional biopsy was performed. Histopathological diagnosis of the biopsied specimen demonstrated diffuse malignant lymphoma of the pleomorphic type. Six cycles of CHOP chemotherapy were very effective for complete remission. Our review of 18 cases in the Japanese literature showed that chemotherapy and radiotherapy were effective for retroperitoneal malignant lymphoma, so due care must be taken in opting for surgery.

Responses to silent Kanji reading of the native Japanese and German in task subtraction magnetoencephalography

The neuromagnetic activities evoked by semantic processing were localized by magnetoencephalography (MEG). We observed distinct time courses of the activities in native speaking Japanese subjects (Japanese speaker) and German subjects (German speaker) during silent reading of Japanese letters; Kanji and meaningless figures made by deforming the Arabian letters. There were significant differences in amplitude of the activities between Kanji and meaningless figure stimuli. The responses with meaningless figure stimuli were subtracted from those with Kanji stimuli to demonstrate the semantic responses. Earlier responses peaked at about 273.3+/-50. 8 and 245.0+/-23.8 ms (mean+/-S.D.) and were mainly located in the right fusiform gyrus (FuG) in the Japanese and German speakers, respectively. All the Japanese speakers constantly showed additional later responses in the left superior temporal gyrus (STG) and the supramarginal gyrus (SmG) at approximately 616.1+/-105.5 ms, whereas no further activity was observed in the German speakers who did not know the meaning of each Kanji. Because the later responses in the STG and SmG in the Japanese speakers were only observed in their dominant hemisphere, we believe the source of these responses to be part of the neural basis of Kanji semantic processing. The task subtraction MEG analysis could be a powerful method to discriminate distinct responses and visualize the neural networks involved in semantic processing.

Motor, somatosensory and auditory cortex localization by fMRI and MEG

Functional magnetic resonance imaging (fMRI) and magnetoencephalography (MEG) were performed in six subjects during self-paced finger movement performance, tactile somatosensory stimulation and binaural auditory stimulation using identical stimulation paradigms. Both functional imaging modalities localized brain activity in adjacent areas of anatomically correct cortex. The mean distances measured between fMRI activity and the corresponding MEG dipoles were 10.1 mm (motor), 10.7 mm (somatosensory), 13.5 mm (auditory right hemisphere) and 14.3 mm (auditory left hemisphere). The distances found may reflect the correlation between electrophysiological and hemodynamic responses due to the different underlying substrates of neurophysiology measured by fMRI and MEG: BOLD contrast vs neuronal biomagnetic activity.