The liquid-state 31P-nuclear magnetic resonance study on microfiltrated milk

To gain further insight into diversiform phosphorus in bovine milk, we separated skim milk into casein micelle and serum fractions by microfiltration and subjected them to liquid-state 31P-nuclear magnetic resonance (NMR) spectroscopy. As previously reported, the skim milk spectrum showed a broad and indistinct peak from phosphoserine residue (SerP) of casein. In the casein micelle spectrum, however, the SerP peak was more clearly observed with a phosphate peak that may be from micellar calcium phosphate (MCP). The serum spectrum was the same as skim milk spectrum, except for SerP peak. Furthermore, two types of casein micelle fractions, with 0.90 and 1.04 of [beta-casein + kappa-casein]/[alpha(s1)-casein + alpha(s2)-casein] ratios were generated by different temperature microfiltrations, occurring because beta-casein is released from the micelle at a low temperature. The shape of SerP peaks changed dramatically in both the casein micelle spectra, when the temperature dropped from 35 to 5 degrees C. Deconvolution analysis indicated that each SerP peak comprised the same set of four peaks. Half-width and composition discriminated between the two types of casein micelle fractions. As a consequence, there was significant interaction between casein micelle and milk serum, causing cloudiness of SerP in the liquid-state 31P-NMR spectrum of milk. Casein composition influenced the SerP-MCP interaction in micellar structure. Shape changing of the SerP peak was discussed in connection with beta-casein-release phenomenon.

Anti-phosphatidylserine/prothrombin antibodies are not frequently found in patients with unexplained recurrent miscarriages

OBJECTIVE

To determine whether the presence of anti-phosphatidylserine/ prothrombin antibodies (anti-PS/PT) can be a major factor in otherwise unexplained recurrent miscarriages.

PATIENTS AND METHODS

Eighty-one consecutive patients with history of 2 or more recurrent miscarriages were studied. Patients with history of overt thrombotic events were not included. Patients were examined for plausible causes of miscarriages, and titer of IgG, IgM and IgA anti-PS/PT were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Thirty-five patients had one or more plausible causes of recurrent miscarriages, including 12 positive for well-established anti-phospholipid antibodies, such as anti-beta2-glycoprotein I. None of the patients included in this study was found to be positive for anti-PS/PT.

CONCLUSION

Detection of anti-PS/PT in addition to other anti-phospholipid antibodies does not seem to aid in the evaluation of patients with unexplained recurrent miscarriages.

Association between job strain and prevalence of hypertension: a cross sectional analysis in a Japanese working population with a wide range of occupations: the Jichi Medical School cohort study

OBJECTIVES

To explore the association between the prevalence of hypertension in a Japanese working population and job strain (a combination of low control over work and high psychological demands), and to estimate this association in different sociodemographic strata.

METHODS

From a multicentre community based cohort study of Japanese people, sex specific cross sectional analyses were performed on 3187 men and 3400 women under 65 years of age, all of whom were actively engaged in various occupations throughout Japan. The baseline period was 1992-95 [corrected]. The association between job characteristics--measured with a Japanese version of the Karasek demand-control questionnaire--and the prevalence of hypertension defined by blood pressure and from clinical diagnoses were examined. Adjustments were made for possible confounders. The analyses were repeated for stratified categories of occupational class, educational attainment, and age group.

RESULTS

In men, the level of job strain (the ratio of psychological job demands to job control) correlated with the prevalence of hypertension. In a multiple logistic regression model, job strain was significantly related to hypertension (odds ratio 1.18; 95% confidence interval 1.05 to 1.32), after adjustment for age, employment (white collar v blue collar), marital status, family history of hypertension, cigarette smoking, alcohol intake, physical activity, and body mass index. The stratified analyses showed significant excess risks in the subordinate groups compared with managers, blue collar workers, less educated workers, and the older age groups. This association was not significant in women. Multiple linear regression analyses, with systolic and diastolic blood pressures as dependent variables, did not show any significant association.

CONCLUSIONS

The findings provided limited proof that job strain is related to hypertension in Japanese working men. Older men in a lower social class may be more vulnerable to the hypertensive effects of job strain.

Tanycytic ependymoma in association with neurofibromatosis type 2

A rare case of tanycytic ependymoma associated with neurofibromatosis type 2 (NF2) is presented for the first time, with emphasis on its clinical course and histopathological features. A 30-year-old man had developed gait disturbance in his childhood, and harbored multiple tumors in spinal nerve roots, in the intradural extramedullary and intramedullary spinal cord. The spinal root tumor and intradural extramedullary tumor were histologically diagnosed as schwannoma and meningioma, respectively. Magnetic resonance imaging showed two intramedullary cystic lesions, one in the cervical and the other in the thoracic spine. Because his sensorimotor dysfunction in the lower extremities continued to worsen gradually, three of the multiple nodular tumors in the thoracic cystic lesion were removed. All three tumors were composed of eosinophilic piloid cells with modest nuclear pleomorphism. No Rosenthal fibers were found. A concentration of slender eosinophilic cellular processes surrounding the vascular wall was seen. Periodic acid Schiff and Masson trichrome-positive balloons were seen in the extracellular space. Detection of ependymal rosettes, although only few in number, led the diagnosis as a tanycytic ependymoma. Recognition of this ependymoma variant should be emphasized to avoid confusion with pilocytic astrocytoma or intramedullary schwannoma.

Association between job stress and depression among Japanese employees threatened by job loss in a comparison between two complementary job-stress models

OBJECTIVES

This study compared the separate effects produced by two complementary stress models--the job demand-control model and the effort-reward imbalance model--on depression among employees threatened by job loss.

METHODS

A cross-sectional analysis was conducted to examine these associations among 190 male and female employees who responded to a self-administered questionnaire in a small Japanese plant with economic hardship. The employees were engaged in 2 job types--direct assembly line and indirect supportive tasks--and the latter was threatened by job loss because of downsizing. Independent variables were measured by the Japanese versions of Karasek's demand-control questionnaire and Siegrist's effort-reward imbalance questionnaire. Depression was assessed by the Center for Epidemiologic Studies Depression Scale.

RESULTS

The employees with indirect supportive tasks (target for downsizing) were more likely to have depressive symptoms than direct assembly-line workers. Job strain, a combination of high demand and low control at work, was more frequent among the latter, while the combination of high effort and low reward was more frequent among the former. After adjustment for work environment factors, low control [odds ratio (OR) 4.7], effort reward imbalance (OR 4.1), and overcommitment (the person characteristic included in the effort-reward imbalance model) (OR 2.6) were independently related to depression. There is some indication that these effects were particularly strong in the subgroup suffering from potential job loss.

CONCLUSIONS

This study confirms that the 2 job stress models identify different aspects of stressful job conditions. Moreover, effort-reward imbalance and low control at work are both associated with symptoms of depression.

Mannose-binding lectin gene: polymorphisms in Japanese patients with systemic lupus erythematosus, rheumatoid arthritis and Sjögren's syndrome

Mannose-binding lectin (MBL) is a key element of the innate immunity, with a structure similar to complement C1q. Serum MBL levels are greatly affected by the polymorphisms of the MBL gene. In particular, codon 54 mutation of the MBL gene results in a significant reduction of serum MBL. To determine whether polymorphism of the MBL gene is associated with occurrence of systemic lupus erythematosus (SLE), rheumatoid arthritis and Sjögren's syndrome in the Japanese population, we analyzed the MBL gene polymophisms of these patients and controls, by polymerase chain reaction-restriction fragment length polymorphism methods. We found that patients studied had a significantly higher frequency of having homozygous codon 54 mutation compared to controls. In particular, patients with SLE or Sjögren's syndrome showed higher probabilities of being homozygous for this mutation. Among subjects with the same genotype, SLE patients tended to have higher serum MBL concentration than controls. Analysis of the promotor region suggested that SLE patients heterozygous for the codon 54 mutation have a higher probability of having a low producing haplotype for the gene without the codon 54 mutation. We conclude that persons homozygous for codon 54 mutation of the MBL gene may be prone to occurrence of autoimmune disorders including SLE, in the Japanese. MBL may have protective effects on occurrence and progression of SLE.

Ectopic arachnoid granulomatosis: a case report

BACKGROUND

Arachnoid granulation can sometimes show hypertrophy, developing extensively apart from the venous sinus, and in that case, a differential diagnosis should be made between this granulation and tumors. In this case, we hypothesized that cerebrospinal fluid was absorbed in the region of abnormal stains revealed by angiography.

CASE DESCRIPTION

A 67-year-old female with headache was admitted to our hospital. A plain radiograph revealed accumulated numerous osteolytic lesions in the right frontal bone. T1-weighted magnetic resonance (MR) images demonstrated mixed-intensity lesions. On the T2-weighted MR images, we observed that the lesions were mixed, with areas of the same intensities as gray matter and cerebrospinal fluid. An abnormal vascular stain from the frontal branch of the middle meningeal artery was confirmed. After a craniotomy, numerous white granular masses were observed. These masses had penetrated the dura mater and adhered rigidly to the arachnoid membrane. Histological examination revealed them to be normal arachnoid granulations and villi.

CONCLUSION

This case was diagnosed as an ectopic arachnoid granulomatosis. No case report has previously been published describing numerous arachnoid granulations away from the venous sinuses.

A cellular variant of supratentorial hemangioblastoma

Supratentorial hemangioblastomas are rarely seen, especially in children and adolescents. We report the case of a 17-year-old male with supratentorial hemangioblastoma. Neuroimaging demonstrated a cystic lesion within the right parietal lobe. Systemic examination revealed no abnormality. The lesion was not attached to the dura and was not associated with von Hippel-Lindau disease. It was very difficult to confirm the final diagnosis of this case, in spite of extensive examination by light microscopy, immunohistochemical studies, and electron microscopy.

Stem cell factor prevents Fas-mediated apoptosis of human erythroid precursor cells with Src-family kinase dependency

The Fas ligand (Fas-L) expressed on mature erythroblasts may induce apoptosis of more immature erythroid cells that express Fas, whereas stem cell factor (SCF) may prevent Fas-mediated cell death in hematopoietic progenitor cells. The manner in which SCF prevents Fas-mediated cell death still is unclear. Given the essential role of SCF and the potentially important involvement of the Fas/Fas-L system in the development of erythrocytes, we studied mechanisms related to SCF prevention of Fas-mediated apoptosis. We used primary cultured human erythroid colony-forming cells (ECFC) derived from CD34+ cells and enriched glycophorin A positive (GPA+) c-kit+ cells in ECFC. Apoptosis of ECFC was induced by an Fas-L mimetic monoclonal antibody CH11. DNA fragmentation and the activation of caspase-3 and caspase-8 were measured using commercially available kits. Characterization of expanded cells was performed using multiparameter flow cytometry. Lyn kinase activity was measured by enolase kinase assays. SCF inhibited the CH11-induced DNA fragmentation of ECFC as well as enriched GPA+ c-kit+ cells in ECFC, but not those of GPA+ c-kit- cells. SCF also inhibited the activation of caspase-3 and caspase-8, without downregulation of the surface expression of Fas, suggesting that SCF prevents apoptosis through uncoupling of Fas ligation from subsequent caspase activation. PP2, a specific inhibitor of Src-family kinases, antagonized the effects of SCF in preventing Fas-mediated apoptosis. We propose that SCF prevents Fas-mediated apoptosis of erythroid progenitor cells in a manner dependent on the activity of Src-family tyrosine kinases. We also identified active Lyn in erythroid cells. These data suggest the presence of a novel Src-family-dependent function of SCF in the development of erythrocytes.

Occult hepatitis B virus infection in HBs antigen-negative hepatocellular carcinoma in a Japanese population: involvement of HBx and p53

Hepatitis B virus (HBV) genome was reported to be detected in serum or liver tissues in hepatocellular carcinoma (HCC) patients negative for hepatitis B surface antigen (HBsAg). Hepatitis B x (HBx) and p53 protein were reported to play an important role in HBV-related hepatocarcinogenesis. To clarify latent HBV infection in HBsAg- and anti-hepatitis C virus (anti-HCV)-negative HCC in a Japanese population and involvement of HBx and p53 protein in these patients, we performed the sensitive and specific nested polymerase chain reaction (PCR) and immunohistochemical analysis. Of 1,024 HCC patients we saw between 1974 and 1998, 66 (6.4%) were negative for HBsAg and anti-HCV. Serum DNA was amplified by nested PCR by using specific primers of surface (S), core (C) and X regions in 26 patients negative for HBsAg and anti-HCV. Eighteen (69%) patients were positive for either S, C, or X region and the results of PCR were confirmed by Southern blotting. Of 18 PCR-positive patients, 3 were positive for anti-HBs and 9 were positive for anti-HBc, however, one was negative for any HBV markers. In HBsAg-negative and PCR-positive patients, the positive rates of expression of HBx and p53 were 8/13 (62%) and 7/13 (54%), being comparable to those in HBsAg-positive HCC patients. The results of the present study suggest that high prevalence of HBV infection is observed in HBsAg-negative HCC in a Japanese population and expression of HBx and p53 is consistent with a role, in these patients, for the transforming ability of these proteins.

beta(2)-glycoprotein I deficiency: prevalence, genetic background and effects on plasma lipoprotein metabolism and hemostasis

beta(2)-glycoprotein I (beta(2)-GPI=apolipoprotein H) is an important autoantigen in patients with the antiphospholipid syndrome. It also plays a role in lipoprotein metabolism, such as anti-atherogenic property, triglyceride removal, and enhancement of lipoprotein lipase. Serum beta(2)-GPI concentration of 812 apparently healthy Japanese individuals was measured by sandwich EIA. Two families with complete beta(2)-GPI deficiency were identified. In one family, all affected had increased serum LDL-cholesterol levels or smaller particle sizes of LDL, while the other had no apparent abnormality in lipid metabolism. Individuals investigated had no history of thrombosis or overt abnormalities in hemostatic tests. A thymine corresponding to position 379 of the beta(2)-GPI cDNA was deleted in every beta(2)-GPI deficient individual. The incidence of this heterozygous deficiency determined by RFLP was 6. 3% in Japanese and none in Caucasians. Heterozygotes had significantly lower concentrations of serum beta(2)-GPI than did those without the mutation, yet no significantly different lipid profiles, such as total cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol, apoA-I, apoB and Lp(a), were observed. A low concentration of beta(2)-GPI seemed not to be associated with apparent abnormality in lipoprotein metabolism.

[Jichi Medical School Social Support Scale (JMS-SSS) revision and tests for validity and reliability]

OBJECTIVE

To develop a perceived social support scale for the Japanese.

METHODS

Participants consisted of a total of 2,150 residents who responded to a perceived social support scale questionnaire in four communities involved in the Jichi Medical School Cohort Study at the study baseline in 1992-1994 (Analysis I) and 380 residents of Akaike town who responded to a questionnaire survey with the revised scale in 1999 (Analysis II). The first analysis was performed to confirm cross validity of the perceived social support scale measuring the availability of functional support from the spouse, family, and friends. The factor structures estimated for each district were compared with each other. The second analysis was set to revise the scale, modified in terms of a 4-point scoring format. The correlation between each item and a social desirability scale score, Cronbach alpha, and correlation coefficients between the revised scale scores and the original scale scores were calculated.

RESULTS

Cross validity was confirmed based on the similarity of the factor structures of the responses obtained from the four different communities. Four selected indices supported the constancy of the factor structures across the communities. For the revised scale, two items were removed from the original scale-items measuring spousal support because of their statistically significant correlations with the social desirability scale score. The first principal component accounted for 57.0% of variance for spousal support, 68.2% for family support, and 67.0% for friends support and uni-dimensionality of the scales was confirmed. Alpha coefficients of the scales were .89, .95, and .94, respectively. Social support levels were stable over a mean period of 6.2 years.

CONCLUSIONS

On an empirical basis, we have been able to develop a perceived social support scale. Homogeneous data from three different sources were obtained which were free from social desirability response bias and thus applicable for Japanese adults.

Severe exacerbation of hepatitis after short-term corticosteroid therapy in a patients with "latent" chronic hepatitis B

We present a case of severe exacerbation of hepatitis after short-term corticosteroid therapy for chronic inflammatory demyelinating polyneuropathy (CIPD) with "latent" chronic hepatitis B showing no HBV-related antigens and antibodies. After corticosteroid pulse therapy for CIPD, the patient had severe exacerbation of hepatitis twice. Although she did not show any hepatitis B virus (HBV)-related antigens or antibodies, sequences of HBV were detected in serum and liver by a nested polymerase chain reaction. A sequence analysis of HBV at the second exacerbation showed that the G-to-A point mutation at nucleotide 1896 that converted codon 28 from tryptophan (TGG) to a stop codon (TAG) in the precore region resulted in amino acid change, which has been frequently observed in fulminant hepatitis and severe hepatitis in Japan.

Occult hepatitis B virus infection in HBs antigen-negative hepatocellular carcinoma in a Japanese population: involvement of HBx and p53

Hepatitis B virus (HBV) genome was reported to be detected in serum or liver tissues in hepatocellular carcinoma (HCC) patients negative for hepatitis B surface antigen (HBsAg). Hepatitis B x (HBx) and p53 protein were reported to play an important role in HBV-related hepatocarcinogenesis. To clarify latent HBV infection in HBsAg- and anti-hepatitis C virus (anti-HCV)-negative HCC in a Japanese population and involvement of HBx and p53 protein in these patients, we performed the sensitive and specific nested polymerase chain reaction (PCR) and immunohistochemical analysis. Of 1,024 HCC patients we saw between 1974 and 1998, 66 (6.4%) were negative for HBsAg and anti-HCV. Serum DNA was amplified by nested PCR by using specific primers of surface (S), core (C) and X regions in 26 patients negative for HBsAg and anti-HCV. Eighteen (69%) patients were positive for either S, C, or X region and the results of PCR were confirmed by Southern blotting. Of 18 PCR-positive patients, 3 were positive for anti-HBs and 9 were positive for anti-HBc, however, one was negative for any HBV markers. In HBsAg-negative and PCR-positive patients, the positive rates of expression of HBx and p53 were 8/13 (62%) and 7/13 (54%), being comparable to those in HBsAg-positive HCC patients. The results of the present study suggest that high prevalence of HBV infection is observed in HBsAg-negative HCC in a Japanese population and expression of HBx and p53 is consistent with a role, in these patients, for the transforming ability of these proteins.

Alternative splicing forms of the human CD1D gene in mononuclear cells

CD1d is a critical molecule for the presentation of lipid antigens to natural killer (NK) T cells. To investigate the molecular complexity of CD1d, alternatively spliced transcripts in peripheral blood mononuclear cells from three healthy subjects were analyzed by PCR and sequencing methods. We found eight alternatively spliced variants of the CD1D gene (V1-V8), seven of which are newly established variants (V2-V8). V1 and V4 are in-frame; however, the other six variants (V2, V3, V5-V8) are out-of-frame. V1, V2, V4, and V5 lack a beta(2)-microglobulin binding site (alpha3 domain), indicating the unstable presentation of the CD1d molecule on the surface. In V2 and V5, the transmembrane region is absent, supporting a soluble CD1d. In the V3-V8 variants, the antigen binding region (alpha1 and alpha2 domains) is partially defective, suggesting incomplete functional products. In contrast, the V1 and V2 transcripts bear the complete antigen binding site, resulting in functional proteins. Especially, the V2 splicing variant might function as an inhibitory soluble CD1d molecule and regulate the presentation of antigens on APC to NKT cells.

Mannose-binding lectin polymorphisms in patients with hepatitis C virus infection

BACKGROUND

Persistent infection with hepatitis C virus (HCV) leads to liver cirrhosis (LC) and often to liver cancer. Little is known about host factors that determine the variable natural history. Mannose-binding lectin (MBL) is an important constituent of the innate immune system. In white patients there is an association between codon 52 mutation of the MBL gene and persistent hepatitis B virus (HBV) infection. To determine whether MBL gene polymorphisms affect the course of HCV infection, we investigated the association between MBL gene polymorphisms and HCV infection in Japanese subjects.

METHODS

Fifty-two HCV-infected Japanese patients (8 with chronic inactive hepatitis (CIH), 31 with chronic active hepatitis (CAH), 13 with LC) and 50 normal controls were studied. MBL gene mutations were determined by means of polymerase chain reaction and restriction fragment length polymorphism analyses.

RESULTS

Codon 52 and codon 57 mutations were absent in all subjects. Homozygous mutation in codon 54 was present in one (0.9%) patient. Heterozygous codon 54 mutation was present in 17 (32%) of the 52 patients and in 21 (41%) of the controls. No significant difference in the frequency of codon 54 mutation was observed between patient and control groups. However, although no significant relationship was observed between MBL polymorphisms and the levels of HCV RNA, all patients with heterozygous or homozygous codon 54 mutations had CAH or LC. In contrast, 8 of the 34 patients without codon 54 mutation remained at CIH. (P = 0.0405).

CONCLUSION

MBL may be one of the factors that influence the course of HCV infection.

Association of autoantibodies against the phosphatidylserine-prothrombin complex with manifestations of the antiphospholipid syndrome and with the presence of lupus anticoagulant

OBJECTIVE

To clarify the association of autoantibodies against prothrombin with the clinical manifestations of the antiphospholipid syndrome (APS) and with the presence of lupus anticoagulant (LAC).

METHODS

We examined 265 patients who visited our autoimmune disease clinic. IgG and IgM antiprothrombin antibodies were tested by enzyme-linked immunosorbent assay (ELISA) as either antiphosphatidylserine-prothrombin complex (aPS/PT) antibodies or as antibodies against prothrombin coated on irradiated ELISA plates (as antigen) (aPT). IgG, IgM, and IgA anticardiolipin (aCL) antibodies and their beta2-glycoprotein I (beta2GPI) dependency were also evaluated by ELISA. LAC was tested by 3 different methods.

RESULTS

The presence of aPS/PT, but not of aPT, significantly correlated with the clinical manifestations of APS (odds ratio [OR] 4.39, 95% confidence interval [95% CI] 2.06-9.38), and aPS/PT antibodies were as specific as beta2GPI-dependent aCL for APS (93.1% for both). IgG aPS/PT strongly correlated with the presence of LAC as detected using the dilute Russell viper venom time test (OR 38.2, 95% CI 13.4-109.1).

CONCLUSION

Antiprothrombin antibodies are heterogeneous and their clinical relevance depends on the method of detection applied. Positive results on the aPS/PT test can serve as a marker of thrombotic events in patients with autoimmune diseases.

Coagulation and fibrinolytic activities in 2 siblings with beta(2)-glycoprotein I deficiency

beta(2)-Glycoprotein I (beta(2)GPI) is a major antigen for antiphospholipid antibodies, and its multiple in vitro functions have been reported. This glycoprotein not only down-regulates thrombin formation by inhibiting contact activation or prothrombinase activity, but also up-regulates coagulation by reducing protein C anticoagulant activity. However, the in vivo roles of beta(2)GPI remain obscure. Coagulation and fibrinolytic characteristics were investigated in individuals with beta(2)GPI deficiency. An apparently healthy woman and her brother are homozygotes for beta(2)GPI deficiency. In these patients, Russell viper venom time was shortened (40.4 seconds; normal range, 47.8 +/- 4.95 seconds), but all markers of thrombin generation and fibrin turnover were within normal ranges. Exogenous activated protein C adequately prolonged the clotting time of the beta(2)GPI-deficient plasma, and euglobulin lysis time was also normal. Thus, elevated thrombin generation, enhancement of activated protein C response, and an altered fibrinolytic system were not found in congenitally beta(2)GPI-deficient plasma. (Blood. 2000;96:1594-1595)

Proteolytic cleavage of beta(2)-glycoprotein I: reduction of antigenicity and the structural relationship

Binding of beta(2)-glycoprotein I (beta(2)-GPI)-dependent anticardiolipin antibodies (aCL) derived from antiphospholipid syndrome (APS) is significantly reduced in aCL ELISA due to loss of the phospholipid (PL) binding property of beta(2)-GPI by plasmin treatment. In the present study, the treatment generated a nicked form of beta(2)-GPI and resulted in loss of antigenicity for the autoantibodies detected in ELISA, using an beta(2)-GPI directly adsorbed polyoxygenated carboxylated plate, the assay system of which was not related to PL binding. The nicked form bound to neither Cu(2+)-oxidized low-density lipoprotein (oxLDL) nor to beta(2)-GPI-specific lipid ligands isolated from oxLDL, the result being a complete loss of subsequent binding of anti-beta(2)-GPI autoantibodies. The conformational change in the nicked domain V was predicted from its intact structure determined by an X-ray analysis (implemented in Protein Data Bank: 1C1Z), molecular modeling and epitope mapping of a monoclonal anti-beta(2)-GPI antibody, i.e. Cof-18, which recognizes the related structure. The analysis revealed that novel hydrophobic and electrostatic interactions appeared in domain V after the cleavage, thereby affecting the PL binding of beta(2)-GPI. Such a conformational change may have important implications for exposure of cryptic epitopes located in the domains such as domain IV.

Malignant pilocytic astrocytoma in the medulla oblongata: case report

A 27-year-old woman visited our hospital with chief complaints of abducens nerve palsy and cerebellar symptoms. On computerized tomographic scanning and magnetic resonance imaging, a tumor with strong enhancement was found on the dorsal side of the medulla oblongata. A tumor was excised by suboccipital craniotomy and C1 laminectomy. Histologically, many Rosenthal fibers together with pilocytic tumor cells were found in some regions, but a very high Ki-67 labeling rate accompanied by cells with nuclei of irregular size and giant cells was observed in other regions. The tumor was diagnosed as malignant pilocytic astrocytoma originating from pilocytic astrocytoma by transformation. The biological behavior of pilocytic astrocytoma is obscure in several respects. We report our experience of a case of malignant pilocytic astrocytoma that developed in the brain stem and progressed extremely rapidly.

Xanthoma of the temporal bone: case report

OBJECTIVE AND IMPORTANCE

Xanthomas of the cranium that are not accompanied by endocrine or metabolic abnormalities are extremely rare. It is very important to understand the pathological features of this disease, for differential diagnosis from other diseases.

CLINICAL PRESENTATION

A 62-year-old woman presented to the hospital with headaches. Cranial x-rays revealed bone destruction in the right temporal bone, with osteosclerosis in the area surrounding the lesion. In computed tomographic scans, the bone cortex was intact and the diploë was dilated because of the large mass of the lesion. T1-weighted magnetic resonance imaging findings were heterogeneous, with areas of hypo- and isointensity; T2-weighted magnetic resonance imaging findings were also heterogeneous, with areas of hypo- and hyperintensity.

INTERVENTION

Total removal of the tumor was performed, followed by cranioplasty using artificial bone.

DIAGNOSIS

Histologically, lipid-containing foamy cells were dense and a cholesterin granuloma was observed. There was no reason to infer other diseases, and a diagnosis of xanthoma of the temporal bone was reached.

CONCLUSION

Xanthomatous lesions are observed in various pathological conditions, including malignant diseases. Xanthomas are benign lesions and the prognoses for patients with these lesions are satisfactory, even after partial excision. Therefore, it is quite important to distinguish xanthomas from other diseases that produce xanthomatous lesions.

In vivo transfer of hepatocyte growth factor gene accelerates proliferation of hepatic oval cells in a 2-acetylaminofluorene/partial hepatectomy model in rats

To clarify the effect of hepatocyte growth factor (HGF) on proliferation of hepatic oval cells, we transferred HGF gene into liver of the Solt-Farber rat model. Male Fisher 344 rats were infected with a recombinant adenovirus carrying the cDNA for HGF (pAxCAHGF) from tail vein. HGF mRNA showed its peak at 4 days, and diminished thereafter. The total and proliferating cell nuclear antigen-positive hepatic oval cells were significantly elevated in HGF-transferred rats, in which stem cell factor and c-kit mRNA increased at each time point. Our results suggest that in vivo transfer of the HGF gene into liver accelerates proliferation of hepatic oval cells in the Solt-Farber model in rats.