Non-copulatory spawning and female participation during early egg care in a marine sculpinHemilepidotus gilberti

The reproductive behavior of a marine sculpin,Hemilepidotus gilberti, was observed in the aquarium. The behavioral sequence comprised fight for terriotory, courtship and fight for females, spawning and caring for the egg mass. Females very slowly deposited eggs enclosed with viscous ovarian fluid onto the substrate. Almost all the eggs contained in the ovary were released in a single spawning, its completion requiring 21–22 min. Territorial males emitted of spawning. Sneaking by neighboring males followed subsequently. This was the first observation of non-copulatory spawning among marine sculpins. Females cared for the eggs for severl days after spawning, and then male alone care continued until hatching (47–49 days after spawning). Participation by females in egg caring is likely to be caused by their spawning only once during the spawning season and the consequent lack of urgency for post-spawning feeding.     

Establishment and characterization of human malignant lymphoma cell line derived from uterine cervix

Human uterine cervical malignant lymphoma (B-cell type) was cultured and the cell line (HIUML) was newly established. The HIUML cells were round in shape and had a tendency to make floating clusters. The cells had a smooth surface or protrusion on the margin of the cytoplasm, and proliferate in floatation. The population doubling time was about 32 hours and 42 or more passages were successfully observed in two years. The HIUML cells were not transplantable into nude mice but were successfully done in the cheek pouch of hamster with formation of malignant lymphoma. Epstein-Barr virus was detected in the HIUML cells.     

Adaptive responses to oxygen stress in obligatory anaerobes Clostridium acetobutylicum and Clostridium aminovalericum

Clostridium acetobutylicum and Clostridium aminovalericum, both obligatory anaerobes, grow normally after growth conditions are changed from anoxic to microoxic, where the cells consume oxygen proficiently. In C. aminovalericum, a gene encoding a previously characterized H2O-forming NADH oxidase, designated noxA, was cloned and sequenced. The expression of noxA was strongly upregulated within 10 min after the growth conditions were altered to a microoxic state, indicating that C. aminovalericum NoxA is involved in oxygen metabolism. In C. acetobutylicum, genes suggested to be involved in oxygen metabolism and genes for reactive oxygen species (ROS) scavenging were chosen from the genome database. Although no clear orthologue of C. aminovalericum NoxA was found, Northern blot analysis identified many O2-responsive genes (e.g., a gene cluster [CAC2448 to CAC2452] encoding an NADH rubredoxin oxidoreductase-A-type flavoprotein-desulfoferrodoxin homologue-MerR family-like protein-flavodoxin, an operon [CAC1547 to CAC1549] encoding a thioredoxin-thioredoxin reductase-glutathione peroxidase-like protein, an operon [CAC1570 and CAC1571] encoding two glutathione peroxidase-like proteins, and genes encoding thiol peroxidase, bacterioferritin comigratory proteins, and superoxide dismutase) whose expression was quickly and synchronously upregulated within 10 min after flushing with 5% O2. The corresponding enzyme activities, such as NAD(P)H-dependent peroxide (H2O2 and alkyl hydroperoxides) reductase, were highly induced, indicating that microoxic growth of C. acetobutylicum is associated with the expression of a number of genes for oxygen metabolism and ROS scavenging.     

Purification and characterization of an H<Subscript>2</Subscript>O-forming NADH oxidase from <Emphasis Type="Italic">Clostridium aminovalericum</Emphasis>: existence of an oxygen-detoxifying enzyme in an obligate anaerobic bacteria

Clostridium aminovalericum, an obligate anaerobe, is unable to form colonies on PYD agar plates in the presence of 1% O₂. When grown anaerobically in PYD liquid medium, the strain can continue normal growth after the shift from anoxic (sparged with O₂-free N₂ carrier-gas) to microoxic (sparged with 3% O₂/97% N₂ mixed carrier-gas) growth conditions in the mid exponential phase (OD₆₆₀=1.0). When the strain grew under 3% O₂/97% N₂, the medium remains anoxic. Thirty minutes after beginning aeration with 3% O₂, the activity of NADH oxidase in cell-free extracts increased more than five-fold from the level before aeration. We purified NADH oxidase to determine the characteristics of this enzyme in an obligate anaerobe. The purified NADH oxidase dominated the NADH oxidase activity detected in cell-free extracts. The enzyme is a homotetramer composed of a subunit with a molecular mass of 45 kDa. The enzyme shows a spectrum typical of a flavoprotein, and flavin adenine dinucleotide (FAD) was identified as a cofactor. The final product of NADH oxidation was H₂O, and the estimated K_m for oxygen was 61.9 M. These data demonstrate that an O₂-response enzyme that is capable of detoxifying oxygen to water exists in C. aminovalericum.Abbreviations NRIC NODAI Research Institute-Culture Collection Center, Tokyo University of Agriculture, Tokyo, Japan - SDS-PAGE sodium dodecyl sulfate polyacrylamide gel electrophoresis - PMSF phenylmethylsulfonyl fluoride     

Panosialins, inhibitors of an α1,3-fucosyltransferase Fuc-TVII, suppress the expression of selectin ligands on U937 cells

Panosialins A and B were isolated as inhibitors of an 1,3-fucosyltransferase, Fuc-TVII, which is a key enzyme in the biosynthesis of selectin ligands, from culture broth of Streptomyces sp. Panosialins A and B inhibited the Fuc-TVII activity with IC50 values of 4.8 and 5.3 g/ml, respectively. Panosialin A suppressed expression of selectin ligands on U937 cells, and inhibited the cell adhesion to immobilized E-selectin-immunoglobulin. Panosialins are the first reported Fuc-TVII inhibitors which can suppress the biosynthesis of selectin ligands and then inhibit selectin-mediated cell adhesion.     

Enhancement of depressed lymphokine activated killer cell activity in patients with hepatocellular carcinoma

Hepatocellular carcinoma (HCC) patients can be divided into two groups according to the degree of lymphokine activated killer (LAK) cell activity; a high LAK activity group (H-LAK-HCC) and a low LAK activity group (L-LAK-HCC). Interferon-gamma (IFN-gamma) production is severely defective in L-LAK-HCC but not defective in H-LAH-HCC. IFN-gamma production is suppressed with the addition of anti-Tac in dose dependent manner, though LAK activity is suppressed only in the presence of high concentration of anti-Tac. LAK activity is suppressed with the addition of anti-IFN-gamma, which is most prominent when the antibody is present during the first 12 hr of incubation. LAK generation is enhanced with the addition of recombinant IFN-gamma, which is most prominent when it is present during the first 12 hr of incubation. However, this enhancing effect is less prominent in L-LAK-HCC as compared to normals, liver cirrhosis, and H-LAK-HCC. This enhancement is regarded to depend on the presence of Leu7⁺ and Leu11⁺ subset, as this enhancement is abandoned and IFN-gamma production is inhibited when either of these subsets is deleted. These data suggest that IFN-gamma production and the participation of Leu7⁺ and Leu11⁺ subsets is important in sufficient LAK generation, and that poor IFN-gamma production and insufficient response to IFN-gamma may be the cause of severely defective LAK generation in L-LAK-HCC.     

Parasperm: morphological and functional studies on nonfertile sperm

Sperm polymorphism, a phenomenon in which more than one type of sperm is produced within a species, occurs widely in animals from invertebrates to vertebrates. Sperm in this phenomenon can be categorized into fertile sperm and nonfertile sperm on the basis of fertilization ability. Nonfertile sperm can be further classified into parasperm and aberrant deformed sperm. Parasperm are sperm produced through a constant developmental process along with normal fertile eusperm, and they are readily distinguished from deformed sperm, which are irregularly crippled by unpredictable errors at certain stages during spermatogenesis. Sperm identified as parasperm occur widely in invertebrates but are presently quite limited in vertebrates. This may be the result of the deficiency both of studies on parasperm and of clear criteria to identify parasperm in vertebrates. Some vertebrates show unique spermatogenesis, such as symplastic spermatid and semicystic spermatogenesis. Thus, parasperm must be identified by comparing cells in each cyst and in semen, because irregularly shaped cells in the seminal duct could be either parasperm or normal spermatids. Although parasperm are identified by clear criteria in vertebrates, only in cottoid fishes to date, it is possible for parasperm to be discovered in other vertebrates. Recently, roles related to sperm competition have been reported in several species (e.g., the marine cottoid fish Hemilepidotus gilberti), and, with some of them, parasperm production is influenced by an intraspecific factor such as a sex ratio or the density of a population. Sperm competition is one of the important candidates for influencing evolution of parasperm functions, but not all parasperm seem to have a relation to sperm competition. Parasperm function may relate to the ecological conditions of each species that produces parasperm. Studies on parasperm function will be advanced by an ecological approach concerning male fertilization success as well as cytological investigation for parasperm. An erratum to this article is available at .