Molecular cloning of cDNAs expressing SS-B/La protein

Using serum from a patient with Sj?gren's syndrome containing a high titer of anti-SS-B/La antibody, cDNA clones (a representative clone was called pA158) were isolated from a human fibroblast cDNA library in lambda gt11 expression vector. After subcloning of pA158 cDNA into an expression plasmid vector pEX-2, a large amount of the recombinant fusion protein with cro-beta-galactosidase (called pA158EX) was obtained in E. coli culture containing the recombinant pEX-2. Antibodies against pA158EX were purified from the patient serum by Sepharose 4B conjugated with the purified pA158EX protein. Immunofluorescent staining of HEp-2 cells with the anti-pA158EX antibodies showed a speckled nuclear staining. In immunoblot analysis, the anti-pA158EX antibodies reacted with 50 kDa protein that was compatible with SS-B/La protein. Immunoprecipitation of leukocyte lysate with the anti-pA158EX antibodies and the following RNA analysis showed that the antibody precipitated Y5 RNA. These findings indicate pA158 is a cDNA for SS-B/La protein. The purified fusion protein was used for enzyme-linked immunosorbent assay (ELISA). Optical density values of anti-SS-B positive sera were high, but those of anti-SS-B negative sera and healthy donor sera were low. In the Northern blot using human RNA and pA158 cDNA, a single band about 1.8 kb was recognized. A full-length cDNA was further obtained by screening of pcD library using pA158 cDNA as a probe.     

CT myelography with intramedullary enhancement in cervical spondylosis

The authors describe seven cases of cervical spondylosis in which small high-density areas were detected in the spinal cord on delayed computerized tomographic (CT) myelography. These high-density areas are believed to represent cavities or areas of cystic necrosis. In all seven cases the cervical spinal canal was narrow, and the spondylosis was located at multiple levels, causing a so-called "pincer effect." On the CT scans the high-density areas resembled fried eggs in the gray matter. These areas were localized near the abnormal cervical discs. In two cases in which the Brown-Séquard syndrome was noted, the symptoms could be attributed to the morphology of the high-density area on the affected side of the cord. Following decompressive surgery, most of the symptoms improved except for numbness of the upper extremities and motor weakness of hands.     

Relationship between Pathological Characteristics and Radiological Findings on Perfusion MR Imaging of Meningioma

Few studies have reviewed the roles of perfusion magnetic resonance (MR) imaging in the histopathological examination of meningiomas. We analyzed the relationships between radiological findings on perfusion MR imaging and pathological characteristics such as origin of the tumor, mitotic activity, pathological subtype, and perifocal edema formation. The subjects were 21 surgical cases of meningioma preoperatively evaluated by perfusion MR imaging. A region of interest (ROI) was set inside of the tumor, and perifocal edema of the same size, cerebral blood volume (CBV), and cerebral blood flow (CBF) on perfusion MR and diffusion-weighted (DW) imaging were analyzed. These radiological data were evaluated in comparison with histopathological characteristics. On perfusion MR imaging, the average ratio of CBV against the contralateral side was 6.43 (1.13–20.0) and that of CBF was 7.73 (1.34–11.3). There was no significant relationship with perfusion MR imaging data, tumor volume, or perifocal edema volume. However, the large peritumoral edema group often had a higher CBV and CBF than the non-large peritumoral edema group. The skull base group had a significantly higher CBV and lower signal intensity on DW images than the non-skull base group. Signal intensity on DW images was higher in grade II or III than in grade I. Perfusion MR imaging data revealed that the higher ratio of peritumoral edema against tumor size was associated with higher blood flow and blood volume under intratumoral circulatory conditions, and that skull base meningioma had a higher blood volume than non-skull base meningioma.     

Heterotransplantation of experimentally induced dog stomach adenocarcinoma to nude mice.

Heterotransplantation of gastric adenocarcinoma, induced in dog by N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) has been attempted to nude mouse. Biopsied materials from Borrmann 3 type carcinoma, which showed signet-ring cell carcinoma at the subcardiac region of a beagle dog, were inoculated into the muscles of the hind legs of BALB/c-nu/nu nude mice. Serial transmission was obtained in 2 lives, so far 4-5 passages. The histological findings of the grafts were mainly poorly differentiated adenocarcinomas.     

Assessment of high-energy phosphorus compounds in the rat kidney by in situ31P nuclear magnetic resonance spectroscopy: effect of ischemia and furosemide

Summary ³¹P nuclear magnetic resonance (NMR) spectroscopy of the in situ rat kidney was performed by a surface coil method, and the effects of ischemia and furosemide infusion were assessed.³¹P NMR spectra of the kidney subjected to 30 min of ischemia returned completely to the pre-ischemic level after 60 min of reperfusion. But the³¹P NMR spectra after 60 min of ischemia did not recover, even after 120 min of reperfusion. Levels of -ATP and inorganic phosphate (Pi) decreased and the chemical shift of Pi increased after intravenous infusion of furosemide. This increase in chemical shift might signal an alkalotic change in intracellular pH. Furosemide infusion prior to ischemia is thought to protect the kidney from injury induced by 60 min of warm ischemia. The chemical shift of Pi returned to the pre-ischemic level earlier than -ATP and Pi. In conclusion, according to the findings of³¹P NMR spectroscopy, furosemide infusion prior to ischemia may be effective in protecting the kidney against ischemic injury. But the change in Pi peak and the causes of the dissociation of Pi and -ATP should be examined further.     

Reduction in cadmium in blood and dietary intake among general populations in Japan

Blood samples and 24-h duplicates of food were collected in the years around 1980 and then in 1990's from inhabitants of nonpolluted regions in Japan. The 1990 study is still in progress with 286 blood samples and 125 food duplicates already collected from 7 regions. A preliminary analysis is made in the present study with the data obtained from the 7 study regions where the survey was conducted in 1980 and then in 1990, to examine possible changes in dietary cadmium intake (Cd-D) and consequently cadmium levels in blood (Cd-B) during this 10 year period. The food duplicate analysis showed that Cd-D in 1980 was 47.1 g/day (1.74):65 [GM (GSD):N] for men and 27.7 g/day (1.75):65 for women. The counterpart values in 1990 were 29.5 g/day (1.66):40 for men and 23.8 g/day (1.73):85 for women; the difference between the two values for the same sex is significant (P<0.05) both=" in=" men=" and=" in=" women,=" suggesting=" that=" there=" occurred=" about=" 37%=" and=" 14%=" reduction=" in=" dietary=" cadmium=" intake=" during=" this=" 10=" year=" period=" in=" men=" and=" in=" women,=" respectively.=" comparison=" in=" cd-b=" showed=" that=" cd-b=" for=" men=" and=" women=" in=" 1990=" were=" 1.79=">g/l (2.01):121 and 1.84 g/l; (1.67):165, respectively, whereas the counterpart values in 1980 were 3.84 g/l (1.64):123 and 3.57 g/l (1.42):141, respectively, indicating significant (P<0.01) reduction=" in=" cd-b=" in=" both=" sexes=" in=" parallel=" to=" the=" reduction=" in=" cd-d.=" the=" role=" of=" rice=" as=" a=" major=" source=" of=" cadmium=" among=" japanese=" population=" together=" with=" recent=" reduction=" in=" the=" importance=" is=" discussed;=" cd=" in=" rice=" accounted=" for=" 72%=" in=" late=" 1970's,=" whereas=" it=" is=" about=" 35%=" in=" the=" present=">     

Risk factors for hepatocellular carcinoma at baseline and 1 year after initiation of nucleos(t)ide analog therapy for chronic hepatitis B

Nucleos(t)ide analogs (NAs) cannot completely suppress the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB). This study aimed to identify the risk factors for HCC development in naïve CHB patients treated with current NA. Patients receiving NA (n = 905) were recruited retrospectively from the 17 hospitals of the Japanese Red Cross Liver Study Group. All treatment-naïve patients had been receiving current NA continuously for more than 1 year until the end of the follow-up. We analyzed the accuracy of predictive risk score using the area under receiver operating characteristic curve. The albumin–bilirubin (ALBI) score was significantly improved by NA therapy (−0.171 ± 0.396; p < 0.001 at Week 48). A total of 72 (8.0%) patients developed HCC over a median follow-up of 6.2 (1.03–15.7) years. An independent predictive factor of HCC development was older age, cirrhosis, lower platelet counts at baseline and ALBI score, and alpha-fetoprotein (AFP) at 1 year after NA therapy according to multivariate analysis. The accuracy was assessed using the PAGE-B, mPAGE-B, aMAP, APA-B, and REAL-B scores that included these factors. Discrimination was generally acceptable for these models. aMAP and REAL-B demonstrated high discrimination with 0.866/0.862 and 0.833/0.859 for 3- and 5-year prediction from the status of 1 year after NA therapy, respectively. Baseline age and platelet count, as well as ALBI and AFP one year after NA, were useful for stratifying carcinogenesis risk. The aMAP and REAL-B scores were validated with high accuracy in Japanese CHB patients.     

Low grade amplification of MDM2 gene in a subset of human breast cancers without p53 alterations

MDM2 protein is thought to bind to p53 tumor suppressor protein leading to inhibition of p53-mediated transactivation. Amplification of the MDM2 gene has been frequently observed in human sarcoma, and relevant overexpression of the MDM2 protein is assumed to contribute to tumorigenesis through inactivation of the p53 function. In order to determine whether MDM2 amplification plays a role in the development of human breast cancer without genetic alteration of p53, we analyzed, MDM2 gene amplification by quantitative hybridization and genetic alteration of p53, in 32 primary tumors and 26 metastatic lymph nodes. Low grade amplification of the MDM2 gene (2-6 fold) was observed in four cases, none of which showed even subtle genetic alterations of p53 or loss of alleles on 17p. Moreover, in three of the four cases with MDM2 gene amplification, the level of gene amplification in the metastatic lymph nodes was slightly higher than that in the primary tumors. These results, taken together with previous findings, suggest that a subset of breast cancers without genetic alteration of p53 may also arise by inactivation of the p53 function through interaction with the overexpressed MDM2 protein induced by gene amplification.     

The urinary excretion of pyridinium cross-links as markers of bone metastasis in breast cancer

The collagen cross-links, pyridinoline (Pyr) and deoxypyridinoline (D-Pyr) excreted in urine have recently been suggested as new markers of bone metastasis. In a pilot study we measured Pyr and D-Pyr in 61 patients with breast cancer, 16 with known bone metastasis and 45 with no recognized metastasis in bone. Twenty healthy female subjects were also measured as controls. The mean values (+/-SD) of Pyr and D-Pyr in the group with bone metastasis were significantly higher (Pyr: p<0.01, D-Pyr: p <0.05) than those in the group without bone metastasis and in the control group. The mean (+/-SD) values of postmenopausal women were significantly higher than those of premenopausal in the group without bone metastasis (p<0.05) and in the control group (p<0.01). Therefore, the effect of menopause should be taken into account in the diagnosis of bone metastasis by assays of Pyr and D-Pyr. Setting the cut-off values (mean + 2SD of the values of control) for pre and postmenopausal patients, the accuracy for Pyr was 71.4% in premenopausal and 75.8% in postmenopausal patients; and for D-Pyr it was 71.4% and 78.8% respectively. We consider that measurement of urinary collagen cross-links assays can contribute to the early detection of metastatic spread to bone in breast cancer.