Follicle-stimulating hormone (FSH) stimulates the expression of Pin1, a peptidyl-prolyl isomerase, in the bovine granulosa cells

A peptidyl-prolyl isomerase, Pin 1, has been shown to play a role in the regulation of cell cycle progression, both in vitro and in vivo. However, the involvement of Pin 1 during follicular development is not well understood. The aim of this study was first to investigate the expression of Pin 1 mRNA in the granulosa and theca cells of the follicle at different developmental stages of follicles in the bovine ovary, and second, to examine the effects of follicle-stimulating hormone (FSH) and estradiol (E2) on the expression of Pin 1 in the cultured bovine granulosa cells. Follicles were classified into four groups based on the diameter (dominant follicles >8.5mm in diameter, subordinate follicles <8.5mm in diameter) and the relative levels of E2 and progesterone (P4) (E2:P4>1, estrogen active; E2:P4<1, estrogen inactive): i.e. preovulatory dominant follicles (POFs); E2 active dominant follicles (EADs); E2 inactive dominant follicles (EIDs); small follicles (SFs). The expression of the Pin 1 gene was significantly increased in the granulosa cells of EADs as compared with those of other follicles, whereas its expression in theca cells did not differ among follicles at different developmental stages. The concentration of 5 ng/ml FSH alone and the combination of 1 ng/ml E2 and 5 ng/ml FSH stimulated the expression of the Pin 1 gene in bovine granulosa cells. Our data provide the first evidence that Pin 1 expression in the granulosa cells but not the theca cells changes during follicular development, and that FSH stimulate the expression of the Pin 1 gene. These results suggest that Pin 1 regulates the timing of cell proliferation and may act as an intracellular signal responder in the granulosa cells during bovine follicle development.     

A comparison of the immunological effects of propofol and isoflurane for maintenance of anesthesia in healthy dogs

Most anesthetics have an immuno-suppressive effect on cellular and neurohumoral immunity, and research shows that total intravenous anesthesia (TIVA) with propofol has a greater immuno-protective effect than inhalational anesthesia in human medicine. However, in veterinary clinics, these effects remain ambiguous. To clarify the details, we focused on propofol and isoflurane, investigating clinical blood hematology and immunological profiles drawn from healthy dogs under and after two anesthesia techniques. Twelve healthy adult beagles were included in this study, randomly assigned to the propofol anesthesia group (group P: n=6) or the isoflurane anesthesia group (group I: n=6). In both groups, the number of lymphocytes in peripheral blood decreased after 2 hr of anesthesia (2 hr), but group P showed significantly less decrease than group I. For T-lymphocyte subsets examined by flowcytometry, the ratio of CD3+, CD4+ and CD8+ lymphocytes in the peripheral blood mononuclear cell (PBMC) of group P at 2 hr also exhibited a high level compared to group I. Moreover, for mRNA expression of cytokines measured by real-time PCR, the IL2 (pro-inflammatory cytokine) of group P showed no decrease like group I. The IL10 (anti-inflammatory cytokine) of group P also showed no increase like group I, while both cytokines maintained nearly the same level until 2 hr. These results suggest that, compared to propofol, isoflurane had more strongly immuno-suppression caused by anesthesia, and propofol itself might have some immuno-protective effects. Thus, TIVA with propofol might benefit immunological support in the perioperative period of dogs.     

Tetrodotoxin accumulation conflicts with low salinity tolerance in juvenile tiger puffer Takifugu rubripes

We evaluated whether bearing tetrodotoxin (TTX) affects salinity stress in the juvenile tiger puffer Takifugu rubripes. Juveniles of hatchery-reared non-toxic T. rubripes [body weight (BW): 1.7?±?0.2 g, n?=?120] were divided into six tanks and acclimatized to salinity (8.5 ppt) that is equivalent to blood osmolality. Fish in three tanks were fed non-toxic diet, and those in the other three tanks were fed a TTX-containing diet (356 ng/g diet) three times a day until satiation. In each diet treatment, salinity of one tank was kept at 8.5 ppt, and the other two tanks were adjusted to either 1.7 or 34.0 ppt, and fish were reared for another 33 days. Then, we compared survival, growth, TTX accumulation, plasma osmolality, plasma cortisol, and glucose levels among treatments. We detected TTX only in the fish in the TTX-diet groups. Survival was highest at 8.5 ppt (70%) and lowest at 1.7 ppt in the TTX-diet group (20%). The BW was greater at 8.5 ppt, and plasma osmolality was significantly higher at 34.0 ppt than at any other salinities. Plasma cortisol level was significantly higher but glucose level was lower at 1.7 ppt. Possessing TTX at a low salinity may be lethal to tiger puffer juveniles.

     

Recent studies on biological control of plant diseases in Japan

Microorganisms play an enormously important role in plant disease control. Research on biological control of plant pathogens has received major impetus and attracted many researchers during the past few decades due to the increased public concern on hazards associated with the use of synthetic pesticides. From research on utilizing specific antagonistic microorganisms, many effective biological control agents (BCAs) have been found and are increasingly implemented in integrated pest management strategies to control plant diseases. Here current research results on biological control against plant diseases carried out in Japan are reviewed by focusing on major categories of BCAs: fungi, bacteria and actinomycetes and attenuated viruses.     

Impact of paralarvae and juveniles feeding environment on the neon flying squid (Ommastrephes bartramii) winter–spring cohort stock

In this study, we found that there were significant positive correlations between the catch per unit effort (CPUE, a squid abundance index) for the neon flying squid (Ommastrephes bartramii) winter–spring cohort and the satellite‐derived chlorophyll a concentrations in their spawning grounds located at 140–160°E where 21°C < sea surface temperature < 25°C from February to May. The spawning grounds of the winter–spring cohort are located in a quiet stream region, and a particle tracking experiment, based on the velocity field obtained from an ocean data assimilation system, showed that paralarvae and juveniles aged <90 days remained in their spawning grounds and the chlorophyll a concentration in their habitat had a significant positive correlation with the CPUE. A backward particle tracking experiment also showed that the chlorophyll a concentration in the spawning grounds had a significant positive correlation with the autumn–winter mixed layer depth. Based on these results, we hypothesize that the CPUE interannual variability is caused by variations in the feeding environment of the paralarvae and juveniles, which may be linked to autumn–winter mixed layer depth variations.     

Evaluation of immunochromatographic test of Shiga toxin 2e in enrichment cultures of swine edema disease clinical samples

To simplify the diagnosis of swine edema disease, overnight culture supernatants of swine clinical samples were assayed using immunochromatographic test strips we developed previously. Small-intestinal contents, mesenteric lymph nodes, and fecal samples were cultured in casamino acid-yeast extract broth overnight, after which supernatants were loaded onto immunochromatographic test strips to determine whether they could detect Shiga toxin 2e (Stx2e). Among 23 clinical samples in which PCR-identified stx2e-positive E. coli were isolated, samples from seven of ten small-intestinal contents, one of three mesenteric lymph nodes and six of ten fecal samples showed Stx2e-positive reactions in the protein-based immunochromatographic test. Additionally, one small-intestinal content sample, in which stx2e-positive E. coli were not isolated, showed an Stx2e-positive reaction. Furthermore, the immunochromatographic test results of the samples were associated with the toxin concentration determined by sandwich ELISA and cytotoxicity assay results on Vero cells. The toxin concentration range of the samples with positive and negative reactions were 2.1–196.2 ng/ml and 0–12.8 ng/ml, respectively. The sensitivity and specificity of this immunochromatographic test strip calculated from all clinical samples analyzed in this study were 60.9% and 94.4%, respectively. Our immunochromatographic test strip has strong potential for simple and accurate diagnosis for edema disease by detecting toxin expression, complementing the PCR method.     

Stereochemical basis for the insecticidal activity of carbamoylated and acylated pyrazolines

Methyl 3-(4-chlorophenyl)-1-[N-(4-chlorophenyl)carbamoyl]-4-methyl-2-pyrazoline-4-carboxylate was converted to corresponding (1R)- and (1S)-phenethyl esters via its carboxylic acid and acid chloride at the C-4 atom to separate the diastereomers. Their configurations were confirmed by X-ray analysis. Both isomers of the (1R)methylbenzyl ester were subjected to transesterification with sodium methoxide to obtain enantiomers of the starting methyl ester. Their insecticidal activity was measured against American cockroaches (Periplaneta americana (L.)) by injection and against house flies (Musca domestica L.) by topical application under various synergistic conditions with metabolic inhibitors. The activity values of the four α-methylbenzyl esters and the R-isomer of the starting methyl ester were similar. The S-enantiomer of the methyl ester was about 10 and 100 times more active than the R-isomer against the cockroach and the fly, respectively. Some N-arylacetyl and N-aryloxyacetyl derivatives of the starting N-(4-chlorophenyl)carbamoyl compound gave very low activity. Conformation-energy profiles for some compounds suggested that the conformation of substituents on the N-1 atom in the pyrazoline ring has a specific role for the potential insecticidal effects.     

Identifying potential habitat distribution of the neon flying squid (Ommastrephes bartramii) off the eastern coast of Japan in winter

Habitat suitability index (HSI) models were applied to identify the potential habitat distribution of the neon flying squid (Ommastrephes bartramii) off the eastern coast of Japan during winter. We used an ocean reanalysis product, a satellite‐derived dataset, and commercial fisheries data during 2003–2008 to develop the HSI models, and illustrated the characteristics of the ocean environments at the fishing ground of the neon flying squid, focusing on a typical fishing ground formation event in 2006. The estimated HSI fields of the neon flying squid using three‐dimensional (3D) ocean environmental parameters showed a clear relationship between the squid habitat and the edge of a warm core ring south of the Oyashio water; this is considered a key characteristic of fishing ground formation, as noted in Sugimoto and Tameishi (Deep‐Sea Research, 39, 1992 and S183). This result suggests that mixing of the warm and nutrient‐poor Kuroshio water and the cold and nutrient‐rich Oyashio water at the edge of the ring could provide favorable conditions for the foraging of the neon flying squid. The warm water condition in the subsurface layers could be a further advantage to the formation of a stable fishing ground for the neon flying squid. Comparison of the Akaike Information Criteria among a satellite‐data‐based model, a reanalysis‐based model using the same parameters as the satellite‐based model, and a reanalysis‐based model using 3D ocean environmental parameters, showed an apparent improvement in the performance of the reanalysis‐based model using the 3D parameters, reproducing realistic features of the squid fishing ground during the winter of 2006.     

Changes in the immunostaining intensities of follicle-stimulating hormone and luteinizing hormone during ovarian maturation in the female Japanese flounder

The role of gonadotropin (GTH) in the reproduction of the Japanese flounder, Paralichthys olivaceus, was studied by assessing the changes in the apparent activity of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in the pituitary gland during gonadal maturation by immunohistochemical analyses. Corresponding changes in plasma levels of testosterone (T), estradiol-17β (E₂), and 17α,20β-dihydroxy-4–pregnen-3-one (DHP) were also studied. Reared fish at the early spawning to termination stages were sampled from May to August and wild fish at the previtellogenic to termination stages were caught at 3- to 4-week intervals between April and September offshore from the northern mainland of Japan by gill nets. The gonadosomatic index of the reared fish decreased from the early spawning stage to the termination stage, while that of the wild fish increased significantly from the previtellogenic stage to the early spawning stage and decreased thereafter. In the reared fish, the immunostaining intensities of FSH and LH were high during the spawning period, accompanied by high plasma levels of T, E₂, and DHP. In the wild fish, the immunostaining intensities of FSH and LH were low during the previtellogenic stage but increased during the maturing and spawning stages. These results indicate that both FSH and LH are likely associated with oocyte maturation in the Japanese flounder.     

Identification of tightly linked SSR markers for flower type in carnation (Dianthus caryophyllus L.)

Single or double flower type is one of the most important breeding targets in carnation (Dianthus caryophyllus L.). We mapped the D ₈₅ locus, which controls flower type, to LG 85P_15–2 using a simple sequence repeat (SSR)-based genetic linkage map constructed using 91 F₂ progeny derived from a cross between line 85–11 (double flower) and ‘Pretty Favvare’ (single flower). A positional comparison using SSR markers as anchor loci revealed that the map positions of the D ₈₅ locus corresponded to the single locus controlling the single flower type derived from wild D. capitatus ssp. andrzejowskianus. We identified four co-segregating SSR markers on the D ₈₅ locus. Verification of the SSR markers in commercial cultivars revealed that two of the four SSR markers (CES0212 and CES1982) were tightly linked to the D ₈₅ locus, and amplified a 176-bp and 269-bp allele, respectively, which were common and unique to double flower cultivars. The map positions of the D ₈₅ locus and the tightly linked SSR markers will be useful for determining the genetic basis of flower type and for marker-assisted breeding of carnations.