Age-dependent Increases of Calcium, Phosphorus, and Sodium in the Uterine Arteries of Thai

To elucidate compositional changes of the uterine artery with aging, the authors investigated age-related changes of elements in the uterine arteries of Thai. After ordinary dissection by medical students at Chiang Mai University was finished, the uterine arteries were resected from Thai subjects. Thai subjects ranged in age from 27 to 86 years (average age = 63.3 +/- 17.7 years). The element content of the uterine arteries was analyzed by inductively coupled plasma-atomic emission spectrometry. It was found that the Ca, P, and Na contents increased progressively in the uterine arteries of Thai with aging. A significant accumulation of Ca and P in the uterine arteries of Thai was found in the sixties patients, and the accumulation increased markedly in the seventies. Regarding the uterine arteries in subjects more than 60 years, the extent of accumulation of Ca and P in the uterine arteries of Thai was one half of that in the uterine arteries of Japanese. Regarding the relationships among elements, extremely significant direct correlations were found among the contents of Ca, P, Mg, Zn, and Na in the uterine arteries of Thai. As Ca increased in the uterine arteries of Thai, P, Mg, Zn, and Na increased simultaneously in the arteries.     

Nematocyst composition of the cubomedusan Chiropsalmus quadrigatuschanges with growth

The nematocysts of Chiropsalmus quadrigatus (Cubozoa; Cubomedusa; Chirodropidae) were examined to determine if their composition changes with an increase in body size. Fixed tentacles of specimens collected in Okinawa, Japan, were homogenized and their nematocysts were observed under a differential interference contrast microscope. Six nematocyst types were observed in medusae of all sizes microbasic mastigophores (MM), large and small trirhopaloids (lTR and sTR), holotrichous isorhizas (HI), ellipsoidal isorhizas (eI), and ovoid isorhizas (oI). Two other nematocysts, large ovoid isorhizas (loI) and microbasic euryteles (ME), were observed only in small individuals. There was also marked difference in proportion of tentacular nematocysts between small and large individuals. HI was the dominant type in small specimens, while MM and eI were predominant in large specimens. Nematocyst composition in the bell and pedalia also differed between small and large individuals. Bells of small medusae contained oI and sTR, while only oI were observed in most large individuals. The pedalia of small medusae had clusters of MM, ME, sTR, and oI. Such single clusters on pedalium bases were characteristic of small individuals. The pedalia of large individuals contained scattered oI. Tentacles of medusae are used for prey capture, so the changes in the major type of nematocysts in tentacles may reflect changes in prey type.     

Vitamin C depletion increases superoxide generation in brains of SMP30/GNL knockout mice

Vitamin C (VC) has a strong antioxidant function evident as its ability to scavenge superoxide radicals in vitro. We verified that this property actually exists in vivo by using a real-time imaging system in which Lucigenin is the chemiluminescent probe for detecting superoxide in senescence marker protein-30 (SMP30)/gluconolactonase (GNL) knockout (KO) mice, which cannot synthesize VC in vivo. SMP30/GNL KO mice were given 1.5 g/L VC [VC(+)] for 2, 4, or 8 weeks or denied VC [VC(−)]. At 4 and 8 weeks, VC levels in brains from VC(−) KO mice were <6% of that in VC(+) KO mice. Accordingly, superoxide-dependent chemiluminescence levels determined by ischemia-reperfusion at the 4- and 8 weeks test intervals were 3.0-fold and 2.1-fold higher, respectively, in VC(−) KO mice than in VC(+) KO mice. However, total superoxide dismutase activity and protein levels were not altered. Thus, VC depletion specifically increased superoxide generation in a model of the living brain.     

The extremely rapid oligonucleotide hybridization and high throughput detection of microbial gene sequences using fluorescence polarization

The hybridization of oligonucleotide sequences complementary to the genes of Shiga toxins (verotoxins) types 1 and 2 of enterohaemorrhagic Escherichia coli (EHEC) and human hepatitis C virus (HCV) was monitored using fluorescence polarization under the reaction condition of high salt concentration (0.8 M NaCl), which was optimized to obtain a higher rate of hybridization. The time courses of hybridization of fluorescently labeled oligomers (probe DNAs) with the amplified DNA or RNA of the genes were recorded. Two methods, the asymmetric PCR and NASBA, were used to amplify the genetic DNA of Shiga toxins and that of RNA in HCV, respectively. Probe DNA sequences were designed which hybridized extremely rapidly with amplicons of the genes of Shiga toxins types 1 and 2 and that of HCV. In the cases using the three different DNA probes, the hybridization was 90% complete in about 1 min, considerably faster than that of the 3 min reported previously. The rapidity of this hybridization could not be explained by the melting temperature or the G+C content of the probe sequences but its relationship with high order structure of the single stranded DNA or RNA of the amplicons in the solution was strongly suggested.     

Tumor-Specific Transplantation Antigen Activity of Freshly Adenovirus-Infected Cells

Newborn hamsters were inoculated with human adenovirus type 12 (Ad12) within 24 hr of birth for tumor induction, and 15 days later, intercurrently immunized with Ad12-infected cells (KB; HeLa; FL; HEK; MoE; HaE). Tumor development was then observed for 75 days thereafter. Tumor formation was prevented at a statistically significant level by immunization with any of the above-mentioned infected cells. The immunization was effective even with abortively infected cells (HaE; MoE) or with cells infected in the presence of 5-fluorodeoxyuridine. The induced immunity was Ad12-specific, since neither cells infected with Ad2, Ad7 or Ad18 nor CV-1 cells infected with SV40 were able to prevent tumor formation. The most plausible explanation to these findings could be that Ad12-specific tumor-specific transplantation antigen is induced on the surface of freshly virus-infected cells and it is responsible for induction of specific cellular immunity. This gives an experimental support to our hypothesis on the mechanism of induction of cellular immunity against virus infections and to the hypothesis proposed by Habel and by Sjögren to explain the immunoresistance against tumor cells induced following viral immunization.     

Flocculation and pentadecane production of a novel filamentous cyanobacterium <Emphasis Type="Italic">Limnothrix</Emphasis> sp. strain SK1-2-1

Objective

A novel filamentous cyanobacterium, a photosynthesizing microorganism, was isolated from a river, and its unique features of flocculation and pentadecane production were characterized.

Results

Microscopic observations and a phylogenetic analysis with 16S rDNA revealed that this strain was a Limnothrix species denoted as the SK1-2-1 strain. Auto cell-flocculation was observed when this strain was exposed to a two-step incubation involving a standing cultivation following a shaking preincubation. Flocculation was enhanced by blue light at a wavelength at 470 nm and irradiation for several hours to 1 day. Moreover, the strain exhibiting exponential cell growth may preferentially accumulate alkanes as pentadecane C₁₅H₃₂ alkane, which may be used as jet fuel, at a range of approximately 1% in the dry cell weight of flocculated cells.

Conclusion

This is the first study on biofuel production using flocculated cells in which the specific manner of production may be regulated by cultivation conditions.