Analysis of the replication mode of double minutes using the PCC technique combined with BrdUrd labeling

A cultured line of neuroblastoma cells (NB) was found to contain double minute chromosomes (DMs). DMs have been reported to be acentric and, therefore, to be segregated randomly into daughter cells without separating their sister elements. When NB cells were fused with Chinese hamster metaphase cells, prematurely condensed chromosomes (PCCs) were induced. DMs seen together with G₂ PCCs appeared to be closely paired, dot-like structures resembling DMs observable in metaphase cells. In contrast, DMs in G₁ cells showed a tendency to become single as the stage progressed so that the majority of DMs in late G₁ cells were actually no longer double. DMs in S-phase cells, however, again appeared double. These results clearly indicate why DMs are invariably double and never assume a quadruple configuration in metaphase cells in spite of their non-disjunctional segregation at anaphase. Such a characteristic mode of DM replication was further confirmed by a 5-bromo-2-deoxyuridine (BrdUrd) labeling experiment: when NB cells were exposed to BrdUrd for two successive rounds of DNA replication prior to PCC induction, half of the resulting single G₁ minutes as well as G₁ PCCs stained dark and the other half stained light after staining for sister chromatid differentiation.     

In vitro establishment of human fibroblasts of lysosomal diseases,GM1-gangliosidosis and Sandhoff disease,by transformation with origin-minus SV40 DNA

The permanent human cell lines preserving defects of lysosomal enzymes, G_M1-1019-SV and SA-1077-SV, were established from the respective fibroblasts from patients with G_Ml-gangliosidosis and Sandhoff disease by transfection with replication origin-minus simian virus 40 DNA. These ceils grow rapidly without entering senescence during more than 120 population doublings. The activity of -galactosidase in G_M1-1019-SV and of B-N-acetylhexosaminidase in SA-1077-SV was respectively 40- and 180-fold lower than that of normal fibroblasts.     

Effects of the Cortex on Light- and Kinetin-Induced Accumulation of Betacyanin in the Epidermal Tissue of Phytolacca americana

Accumulation of betacyanin in the peeled green epidermis fromthe stem of P. americana was induced by incubating the epidermisin Murashige and Skoog's medium, under light, and was promotedby the presence of kinetin. However, in the epidermal tissuewith cortex attached, the accumulation of betacyanin was inhibited. (Received March 27, 1989; Accepted January 24, 1990)     

Age-dependent aluminum accumulation in the human aorta and cerebral artery

The purpose of this study was to determine the extent of aluminum (Al) accumulation in the human aorta and cerebral arteries. The Al contents in the aortae and in the cerebral arteries from 23 human subjects was determined by inductively coupled plasma atomic emission spectrophotometry (ICP-AES). The subjects' age range was 45–99-yr-old; 15 of the subjects were males and 8 were females. Al was detected in twelve aortae and in six cerebral arteries, when the entire specimen was analyzed. Two specimens where Al was found in the cerebral arteries contained no Al in the aorta. No relationship to the subject's sex was found. When related to age, two groups were established. Group L (45–75 yr old) and group H (>75 yr old), which exhibited aortal Al concentrations of 33.3 and 72.7%, respectively. When the aortic wall was dissected into the tunica intima, media, and adventitia, Al was found mainly in the tunica media. In the aorta, significant relationships were found between Al and phosphorus (P) levels (r=0.801,p<0.01) and between Al and calcium (Ca) (r=0.661,p<0.05). We have concluded that Al accumulation is age-dependent and that it occurs both in the aorta and in the cerebral artery. In the aorta, accumulation occurs mainly in the tunica media. Both P and Ca appear to enhance aortal Al accumulation.     

Restriction Fragment Length Polymorphism (RFLP) of Genomic DNA of Moraxella (Branhamella) catarrhalis Isolates in a Hospital

Epidemiological typing, based on restriction fragment length polymorphism (RFLP) by pulsed-field gel electrophoresis (PFGE), was attempted for the 38 clinical isolates of Moraxella catarrhalis obtained at Shinshu University Hospital during the years 1987 and 1993. Digestion with SmaI or NotI generated well separable, 12 to 5 genomic DNA fragments ranging from 1,000 kb to 30 kb and the strains could be classified into 14 or 13 types, respectively. The electrophoretic profile differed with the strain in most of them and was hence useful to distinguish the each strain. Investigation for their RFLP have, however, suggested that majority of them, including the type strain ATCC25238, may have derived from a common ancestor.     

Hepatocellular carcinoma associated with chronic Schistosoma mansoni infection in a chimpanzee

Hepatocellular carcinoma associated with chronic Schistosoma mansoni infection in a chimpanzee, estimated to be a 12-year-old and born in West Africa, is reported. The hepatic tumor appeared as a solitary firm nodule, and histological examination revealed well-differentiated hepatocellular carcinoma with a trabecular pattern. Hepatitis B virus and hepatitis C virus infections were excluded by serological testing in that animal. This is the first report of hepatocellular carcinoma in the chimpanzee with schistosomiasis.     

Immobilization ofβ-fructofuranosidase fromAureobasidium on DEAE-cellulose

Summary -Fructofuranosidase, which produces fructo-oligosaccharides (1-kestose and nystose) from sucrose, was purified fromAureobasidium and immobilized on DEAE-cellulose at especially high efficiency (95%). The enzymatic profiles of the immobilized enzyme were almost identical to those of the native form except that the stability was slightly improved. The immobilized enzyme was stable during long-term continuous reaction for up to 360 h.     

Driving forces behind the fluctuating growth of the number of successful nests in an inland population of white-tailed eagles in Hokkaido,Japan

This study aimed to describe the change in the number of successful nests of the white-tailed eagle, Haliaeetus albicilla, for 25 years (1997–2021) along the Teshio River (100 km), Japan, which is a new habitat for this endangered species and identify factors driving the number of nests. The number of nests grew from two to nine. The logistic function fitted in well with the growth, and the capacity of the study area sustaining the successful nests was estimated at 6.5. The precipitation in January and April explained the deviation of the observed values from the model prediction. In particular, heavy rain in April was associated with low numbers. Forty-six nest remains were collected from 17 nest locations. Twelve genera of birds, six genera of mammals, and four genera of fishes were identified. Fish and bird items occupied 93.6% of prey individuals. The fish proportion was similar between high-performance years when the observed number of successful nests was higher than the model prediction and low-performance years with a lower number than the prediction (55.2% and 51.0%). However, it was higher in the nests with two fledglings (63.0%) than those with a single fledgling (41.5%). The nearest neighbor distance (NND) of the successful nests declined with the increase in the number of nests. Based on territory size (the mean NND = 7.8 km), the study area can hold 13 nests. The process and mechanism of the dynamics of the number of nests were discussed, focusing on territoriality and weather effects.