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Poisoning after eating puffer fish containing highly lethal tetrodotoxin (TTX) is widespread in Asia. In 2008, naive inland populations in Bangladesh were exposed to cheap puffer fish sold on markets. In three outbreaks, 141 patients with history of puffer fish consumption were hospitalized. Symptoms of poisoning included perioral paraesthesia, tingling over the entire body, nausea and vomiting, dizziness, headache, abdominal pain and muscular paralysis of the limbs. Seventeen patients (12%) died from rapidly developing respiratory arrest. Blood and urine samples from 38 patients were analyzed using a TTX-specific enzyme-linked immunoassay (ELISA). Medium to high TTX levels were detected (1.7-13.7 ng/ml) in the blood of 27 patients. TTX was below detection level (< 1.6 ng/ml) in 11 blood samples but the toxin was detected in urine. Ten patients had blood levels above 9 ng/ml and developed paralysis; seven of these died. The remaining patients recovered with supportive treatment. High concentrations of TTX and its analogues 4-epiTTX and 4,9-anhydroTTX were also found in cooked puffer fish by post-column liquid chromatography-fluorescence detection. To prevent future instances of puffer fish poisoning of this magnitude, measures should be implemented to increase awareness, to control markets and to establish toxicological testing. To improve the management of this and other poisoning in Bangladesh, facilities for life-saving assisted ventilation and related training of healthcare personnel are urgently needed at all levels of the health system.

The effects of future tropical Pacific sea surface temperature (SST) changes on regional precipitation projections are statistically studied for December–January–February (DJF) and June–July–August (JJA) in the Coupled Model Intercomparison Project phase 3 (CMIP3) experiments. The present climate precipitation responses to Nino3 SST variability appear as an uncertainty with regards to future regional precipitation changes among the CMIP3 model projections. Compared with the CMIP3 models projecting La Nina-like Pacific SST changes, the models projecting El Nino-like Pacific SST changes tend to simulate more precipitation in future DJF over the tropical central Pacific, southeastern North America and the tropical western Indian Ocean, and less over the tropical northwestern Pacific, the tropical South Pacific and tropical South America. For JJA, the models projecting El Nino-like Pacific SST changes tend to simulate greater future precipitation in the tropical central Pacific and less over the Maritime Continent and around Central America. Interestingly, the present climate features of the delayed JJA precipitation response to previous DJF Nino3 SST variability also appear as differences in future JJA precipitation changes between the models projecting future El Nino-like and La Nina-like Pacific SST changes in DJF. Compared to the later models, the former models have a tendency to show more precipitation south of Japan and south of the equator in the central to eastern Pacific, and less in the subtropical northwestern Pacific. CMIP3 model analysis indicates that the projected El Nino-like SST changes are related to the present precipitation climatology of the models in the near-equatorial eastern Pacific for each DJF and JJA season, suggesting the importance of realistically simulating present precipitation climatology in the tropical Pacific for future projections.

To reveal the sensing of tetrodotoxin (TTX) by tiger puffer Takifugu rubripes juveniles and its action in the central nervous system (CNS), we conducted transcriptome analysis using next-generation sequencing for the olfactory system and brain of non-toxic cultured juveniles administered TTX. Sixty-seven million reads from the nasal region (olfactory epithelium and skin) and the brain of each of three individuals of the control, TTX-sensing and TTX-administered juveniles were assembled into 153,958 contigs. Mapping raw reads from each sample onto the nucleotide sequences of predicted transcripts in the T. rubripes genome (FUGU version 4) and the de novo assembled contigs to investigate their frequency of expression revealed that the expression of 21 and 81 known genes significantly changed in TTX-sensing and TTX-administered juveniles in comparison with control juveniles, respectively. These genes included those related to feeding regulation and a reward system, and indicated that TTX ingestion of T. rubripes juveniles is controlled in the feeding center in the brain, that T. rubripes may sense TTX as a reward, and that accumulated TTX directly acts on the central nervous system to adjust TTX ingestion.

High levels of tetrodotoxin (TTX) and of its analogue 6-epi-tetrodotoxin have been detected in skin and liver extracts of the red-spotted newt Notophthalmus viridescens assayed by a post-column fluorescent-HPLC system. Using a monoclonal antibody-based immunoenzymatic technique, TTX was localized in the granular glands of the epidermis as well as in the muscle layer between the muscle fibres, but also in most organs suggesting that TTX is stored in the whole body of the newt and is secreted by skin glands.

Watercore usually spreads in mature ‘Fuji’ apples and may induce flesh browning disorders through unknown mechanisms. We analyzed H2O2 and ascorbic acid (AA) contents and the activities of four enzymes involved in the AA–glutathione (AA–GSH) cycle in watercore and watercore-free tissues in ‘Fuji’ apple fruit during storage. H2O2 levels always were higher in watercore than in watercore-free tissues. AA levels were lower in watercore tissues at harvest and decreased in both tissue types during the storage period. However, AA was completely absent from watercore tissue but not watercore-free tissue three months after harvest. Ascorbate peroxidase (APX) activities were always higher in watercore than in watercore-free tissues, and the activities of dehydroascorbate reductase (DHAR) decreased continuously after harvest in both tissue types. These results suggested that higher production of H2O2 caused by anaerobic conditions in watercore activated APX which acted as a redox signal; the concomitant net consumption of AA was not balanced by the decline of DHAR activity, leading to decreased antioxidant levels. On the other hand, the gradual increases in monodehydroascorbate reductase (MDAR) and glutathione reductase (GR) activity observed during storage accompanied by low AA levels and DHAR activity might indicate a declining efficiency of the AA–GSH cycle.

From October 2006 to December 2007, wild specimens of the pufferfish Takifugu poecilonotus (93 females, 45 males) were collected from the Ariake Sea. Tissue toxicity was examined by mouse bioassay, and tetrodotoxin (TTX) content in the blood plasma by enzyme-linked immunosorbent assay. The relationship between toxicity and maturation was investigated based on changes in the gonadosomatic index: December-March in females and November-March in males, the 'maturation period'; April, 'just after spawning'; and the other months, the 'ordinary period'. Toxicity of both sexes was high throughout the year, but sharply declined in April. In all tissues examined (skin, liver, and ovary) other than testis, toxicity exceeded 1000MU/g or 10,000MU/individual in many individuals. Seasonal profiles of tissue toxicity differed markedly between sexes. In females, liver toxicity was high during the ordinary period, and ovary toxicity was high during the maturation period. In males, little maturation-associated change in the toxin distribution was observed. Plasma TTX levels were similar between the sexes (1.59-15.1MU/ml), and fluctuated largely throughout the year without corresponding changes in tissue toxicity. The percentage of TTX binding to high molecular-weight substances in the plasma varied in association with maturation; the binding ratio fluctuated at relatively low levels during the ordinary period, and stabilized at a high level during the maturation period., Toxicon, 55(2-3), pp.289-297; 2010

We constructed historical (1900–) high-resolution (0.05° × 0.05°) daily precipitation data over the Japanese land area as part of the product of the “Asian Precipitation – Highly-Resolved Observational Data Integration Towards Evaluation of the Water Resources” (APHRODITE) project. This product APHRO_JP is derived from rain gauge observations and is intended to accurately represent both mean and extreme values. Due to new interpolation techniques developed in APHRODITE, estimation accuracy for orographic precipitation is improved, and bias for long-term amount is reduced, even for the early 20th century in which the observation network was sparse in space. Moreover, the product can be used for statistical analysis of heavy precipitation up to about 150 mm/day, over a long term period (≥ 100 years). APHRO_JP enables diverse research, including validation of meso-scale models and analysis of the longterm extreme precipitation trend in Japan.

From October to November 2004, the paralytic shellfish poison (PSP)-producing dinoflagellate Alexandrium tamiyavanichii was observed at Harima-Nada, Seto Inland Sea at a maximum cell density of 4,960 cells/L. The wild cells of the dinoflagellate collected from the same seawaters, and cultured cells derived from them showed toxicity scores of 6.25-15.4 x 10(-4) and 2.7-3.5 x 10(-4) MU/cell, respectively, both of which were much higher than those of previously reported strains. PSP of the wild cells was mainly composed of gonyautoxin (GTX) 5 (40.6-52.4 mol%) and GTX4 (15.6-24.8 mol%), showing a unique composition that was greatly different from those of the previously reported strains, or of the cultured cells, whose main toxin component was GTX3 (average 37.6 mol%). The mussel Mytilus galloprovincialis collected from the same area in the same period accumulated a relatively high level of PSP (13-28 MU/g), suggesting a risk that A. tamiyavanichii may induce high-level PSP contamination of bivalves even at a cell density as low as around 5,000 cells/L.

The toxicity and toxin profiles of the marine pufferfish Takifugu oblongus were investigated from fish collected from Sihanouk Ville, one of the main regions where pufferfish poisonings (PFP) have occurred in Cambodia. Standard mouse bioassay revealed that all specimens collected were toxic, and their toxicities were mainly contained in the ovary. Toxicities ranged from 10 to 132 mouse units (MU) g−1, much higher than the regulatory limit for human consumption (10 MU g−1). The skin, muscle, liver, viscera and testis toxicities were all below 20 MU g−1. Toxic principles in the species were identified as tetrodotoxin (TTX) as the main component and saxitoxin (STX) as a minor. It was confirmed that T. oblongus is a hazardous species that is unsafe for human consumption and that TTX is the likely cause of pufferfish poisonings in Sihanouk Ville. This is the first report of the occurrence of STX both in the indigenous pufferfish and in Cambodian waters.

The 20th century simulations from the World Climate Research Programme’s Coupled Model Intercomparison Project phase 3 (CMIP3) multi-model dataset are examined statistically using numerical skills to capture the characteristics of the models which realistically simulate responses of the tropical western Pacific (TWP) precipitation to sea surface temperature (SST) variability over the Nino3 region [150°-90°W, 5°S-5°N].The simultaneous correlation of precipitation anomaly over the TWP region of [90°-170°E, 20°S-20°N] with Nino3 SST variability is successfully reproduced with relatively high skills for June to August (JJA) as compared with those for December to February (DJF) and March to May. The high skill models have common characteristics of realistically simulating the observed largest precipitation response to Nino3 SST variability over the equatorial central Pacific east of the dateline. Furthermore, the realistic simulation of the climatological mean equatorial precipitation west of the dateline seems to be responsible for the realistic response of the TWP precipitation to Nino3 SST variability.A few of the models successfully simulate the delayed response of the JJA precipitation over the TWP region of [90°-170°E, 10°S-30°N] to the preceding DJF Nino3 SST variability with high skills. Those models reproduce the statistically observed features of subtropical northwestern Pacific SST anomaly, precipitation and SST anomalies over the Indian Ocean in JJA following DJF Nino3 SST variability. Another distinctive characteristic of those models is to reproduce almost null correlation of the equatorial central Pacific SST anomaly in JJA with the preceding DJF season Nino3 SST variability.

We established a standard curve for age estimation of the Japanese grass vole, Microtus montebelli, from eye-lens weight as a tool for analyses of ages in the vole population. Predicted age was given by the equations, x=10(Y+2.00)/3.24 for males, and x=10(Y+1.72)/2.94 for females, where Y is weight of paired lenses in mg and x is predicted age in days. Indices of predictive accuracy of the technique (Syx/Y: the standard error of estimate divided by the mean of Y) were 0.059 and 0.073 for males and females, respectively.

Tetrodotoxin (TTX) was intramuscularly administered to non-toxic cultured specimens of the pufferfish Takifugu rubripes to investigate TTX transfer/accumulation profiles in the pufferfish body. In two groups of test fish administered either 50MU/individual of TTX standard (purified TTX; PTTX) or crude extract of toxic pufferfish ovary (crude TTX; CTTX), TTX rapidly transferred from the muscle via the blood to other organs. The toxin transfer profiles differed between groups, however, from 4 to 72h. In the PTTX group, little TTX was retained in the liver, and most (>96%) of the toxin remaining in the body transferred/accumulated in the skin after 12h, whereas in the CTTX group, a considerable amount of toxin (15%-23% of the administered toxin or 28%-58% of the remaining toxin) was transferred/retained in the liver for up to 24h, despite the fact that 89% of the remaining toxin transferred/accumulated in the skin at the end of rearing period (168h). The total amount of toxin remaining in the entire body at 1-4h was approximately 60% of the administered toxin in both groups, which decreased at 8-12h, and then increased again to approximately 60%-80% at 24-168h. Immunohistochemical observation revealed that the toxin accumulated in the skin was localized at the basal cells of the epidermal layer., Toxicon : official journal of the International Society on Toxinology, 53(1), pp.99-103; 2009

A daily gridded precipitation dataset for 1961-2004 was created by collecting rain gauge observation data across Asia through the activities of the Asian Precipitation—Highly Resolved Observational Data Integration Towards the Evaluation of Water Resources (APHRODITE) project. Our number of valid stations was between 5000 and 12,000, representing 2.3 to 4.5 times the data available through the Global Telecommunication System network, which were used for most daily grid precipitation products. APHRODITE’s daily gridded precipitation (APHRO_V0902) is the only long-term (1961 onward) continental-scale daily product that contains a dense network of daily rain gauge data for Asia including the Himalayas and mountainous areas in the Middle East. The product contributes to studies such as the evaluation of Asian water resources, diagnosis of climate change, statistical downscaling, and verification of numerical model simulation and high-resolution precipitation estimates using satellites. We released APHRO_V0902 datasets for Monsoon Asia, Russia and the Middle East (on 0.5° × 0.5° and 0.25° × 0.25° grids) at http://www.chikyu.ac.jp/precip/. Herein, we show the algorithm and input data of APHRO_V0902.

Many pufferfish of the family Tetraodontidae possess a potent neurotoxin, tetrodotoxin (TTX). In marine pufferfish species, toxicity is generally high in the liver and ovary, whereas in brackish water and freshwater species, toxicity is higher in the skin. In 1964, the toxin of the California newt was identified as TTX as well, and since then TTX has been detected in a variety of other organisms. TTX is produced primarily by marine bacteria, and pufferfish accumulate TTX via the food chain that begins with these bacteria. Consequently, pufferfish become non-toxic when they are fed TTX-free diets in an environment in which the invasion of TTX-bearing organisms is completely shut off. Although some researchers claim that the TTX of amphibians is endogenous, we believe that it also has an exogenous origin, i.e., from organisms consumed as food. TTX-bearing animals are equipped with a high tolerance to TTX, and thus retain or accumulate TTX possibly as a biologic defense substance. There have been many cases of human intoxication due to the ingestion of TTX-bearing pufferfish, mainly in Japan, China, and Taiwan, and several victims have died. Several cases of TTX intoxication due to the ingestion of small gastropods, including some lethal cases, were recently reported in China and Taiwan, revealing a serious public health issue., Marine Drugs, 6(2), pp.220-242; 2008

On the 6th day after girdling, the photosynthesis rate of leaves on the 3-year-old stem, 2-year-old stem and new shoot of a branch of a field-grown 4-year-old apple tree decreased. The starch content in the leaves, bark and wood significantly increased, especially in shoot leaves. In the girdled branch, concomitant with the photosynthesis reduction, on the 6th day after girdling, the stomatal conductance of leaves on the 3-year-old stem, 2-year-old stem and new shoot declined. Under this condition, a significant correlation between the photosynthesis rate and stomatal conductance could be recognized. On the other hand, with girdling, the activity of ribulose-1,5-bisphosphate carboxylase (RuBPcase) per leaf area decreased on the basis of the decrease in RuBPcase activity per unit enzyme protein. The initial activity of RuBPcase per leaf area in shoot leaves decreased. Moreover, the activity of RuBPcase per leaf area significantly correlated with the photosynthesis rate. Based on these results, it is suggested that the decrease in the photosynthesis rate of the sink-limited branch of a young apple tree 6 days after girdling is mainly caused by closing of the stomatal aperture and reduction of RuBPcase activity per leaf area.

リンゴ樹における新梢成長と貯蔵養分の利用との関係を知るために，前年度に15Nと13Cを施与したリンゴ‘ふじ／マルバカイドウ’の1年生樹に切り返し剪定を行い，その後の新梢成長と貯蔵養分の移行について，成長初期（5月），成長旺盛期（6月），成長停止期（9月）に調査した．5月までは新梢の位置に関係なく，個々の新梢長の差は小さかったが，6月には上部の新梢が長くなり，それからその差が顕著になった．新梢長と新梢の15N excess％との間には相関は認められなかったが，15N excess％は9月に顕著に減少した．新梢長と新梢の13C excess％との間には低い負の相関が認められ，5月から6月にかけて大きく減少した．新梢長と15N分配率（％）および13C分配率（％）の間には，5月から9月において有意な正の相関が認められた．これらのことから，上部の長く伸びる枝は，貯蔵された窒素あるいは炭素を相対的により多く利用していることが推察された．そして長い枝と短い枝では貯蔵養分と当年に吸収された養分の利用の度合いには差が無いが，特に，新梢成長には貯蔵された窒素の寄与が炭素に比べてより大きいことが推察された．

In this study, we assessed the toxicity of the horseshoe crab Carcinoscorpius rotundicauda collected from Cambodia within two successive months during rainy (April-May) and dry (December-January) seasons, respectively. Toxicity assessments of the collected specimens by standard mouse bioassay showed marked individual variation, and their toxin profiles by liquid chromatography/mass spectrometry (LC/MS) revealed tetrodotoxin (TTX) was the main toxin while no paralytic shellfish toxins (PSTs) were detected. All specimens were toxic and the highest toxicity values were 315, 113, 60, 47, 44 and 38 mouse units (MU)/g in the tissues of hepatic caecum, egg, viscera, muscle, intestine and testis, respectively. Although the current findings showed that the Cambodian C. rotundicauda was a moderately toxic species, they are not suitable for human consumption due to their toxicity. To the best of our knowledge, this is the first scientific study on toxic marine seafood ever investigated in Cambodian territorial waters.

Puffer fish is prized as a Japanese traditional food and its fin is also used in the cuisine. However, whether the fin is edible or not is determined for convenience from the toxicity of skin, since little information is available about the toxicity of puffer fish fins. In the present study, we examined the toxicity of fins and skin of three toxic species, Takifugu vermicularis, T. snyderi, and T. porphyreus. The toxicity of T. vermicularis fins (< 5-52.4 MU/g) was significantly lower than that of skin (

The physiology of starch degradation in relation to ripening and ethylene was investigated using ‘Tsugaru’ (early-maturing) and ‘Fuji’ (late-maturing) apples (Malus domestica Borkh.). Fruits were harvested at immature and mature stages, and treated with ethylene and 1-methylcyclopropene (1-MCP). In immature fruit of both cultivars, starch content rapidly decreased during storage at 25°C, and 1-MCP had little effect on this change. Ethylene treatment slightly stimulated the degradation of starch, but differences in starch among treatments were small. The respiration rate gradually decreased and ethylene production remained low during storage irrespective of the treatments and cultivars. These results showed that fruit at this stage could not respond to endogenous and exogenous ethylene for inducing the climacteric, and starch degradation did not relate to the climacteric or ethylene. In mature ‘Tsugaru’, 1-MCP treatment significantly inhibited ethylene production and reduced the respiration rate and starch degradation. The effects of 1-MCP and ethylene on starch degradation in mature ‘Fuji’ were small, and starch content decreased drastically in all treatments, although 1-MCP significantly inhibited ethylene production and the respiration rate. It is suggested that ethylene is partially involved in starch degradation in mature ‘Tsugaru’, but not in ‘Fuji’. These results showed that the role of ethylene in starch degradation differs between cultivars and their harvested stages, relating to ripening and physiological characteristics of the fruit.

We have discovered new glycosylated fatty acid amides, stellettosides, from a Stelletta sp. marine sponge. They were detected through LC-MS analysis of the extract combined with the cytotoxicity assay of the prefractionated sample. Their planar structures were determined by analyses of the NMR and tandem FABMS data. Stellettosides A1 and A2 (1 and 2) as well as stellettosides B1-B4 (3-6) were obtained as inseparable mixtures. Careful analysis of the NMR and tandem FABMS data of each mixture, along with comparison of the tandem FABMS data with that of a synthetic model compound, permitted us to assign the structure of the constituents in the mixture. The absolute configuration of the monosaccharide unit was determined by LC-MS after chiral derivatization. The relative configurations of the vicinal oxygenated methines in the fatty acid chains were assigned by the (1)H NMR data of the isopropylidene derivative. The mixture of stellettosides B1-B4 (3-6) exhibit moderate cytotoxic activity against HeLa cells with an IC50 value of 9 μM, whereas the mixture of stellettosides A1 and A2 (1 and 2) was not active at a concentration of 10 μM.

A toxic dinoflagellate responsible for paralytic shellfish poisoning (PSP), Alexandrium catenella (Ac) was fed to the short-necked clam Tapes japonica, and the accumulation and depuration profiles of PSP toxins were investigated by means of high-performance liquid chromatography with postcolumn fluorescence derivatization (HPLC-FLD). The short-necked clams ingested more than 99% of the Ac cells (4 x 10(7)cells) supplied once at the beginning of experiment, and accumulated a maximal amount of toxin (185 nmol/10 clams) after 12h. The rate of toxin accumulation at that time was 23%, which rapidly decreased thereafter. Composition of the PSP toxin accumulated in the clams obviously different from that of Ac even 0.5h after the cell supply, the proportion of C1+2 being much higher than in Ac, although the reason remains to be elucidated. In contrast, a higher ratio of gonyautoxin (GTX)1+4 than in Ac was detected in the toxin profiles of clam excrements. The variation in toxin composition derived presumably from the transformation of toxin analogues in clams was observed from 0.5h, such as reversal of the ratio of C1 to C2, and appearance of carbamate (saxitoxin (STX), neoSTX and GTX2, 3) and decarbamoyl (dc) derivatives (dcSTX and dcGTX2, 3), which were undetectable in Ac cells. The total amount of toxin distributed over Ac cells, clams and their excrements gradually declined, and only 1% of supplied toxin was detected at the end of experiment.

The caligid copepod Pseudocaligus fugu, a common parasite on the body surface of both toxic (Takifugu pardalis) and cultured, non-toxic (Takifugu rubripes) puffer fishes, was isolated and analyzed for the presence of tetrodotoxin (TTX) using a monoclonal anti-TTX antibody-based immunohistochemical technique. Histological sections of female P. fugu from Takifugu pardalis explicitly revealed that positive brown staining was visible in regions of gut and appendages, and also in the general body tissues from the prosome to the urosome. It is absent from the epicuticle, ovary, oviduct, uterus and egg sacs, where clear negative blue color reaction was obtained. In contrast, the caligids on cultured, non-toxic Takifugu rubripes, considered as negative control, had no sign of TTX. The results indicate that there is no vertical transmission of TTX in the parasitic caligids, which could acquire TTX by feeding on the toxic mucus and skin tissues of host puffer fish.

Marine pufferfish (family Tetraodontidae) are believed to accumulate tetrodotoxin (TTX) mainly in liver and ovary through the food chain by ingesting TTX-bearing organisms such as starfish, gastropods, crustacean, flatworms, ribbonworms, etc. Consequently, it is hypothesized that non-toxic pufferfish can be produced if they are cultured with TTX-free diets in netcages at sea or aquaria on land, where the invasion of TTX-bearing organisms is completely shut off. To confirm this hypothesis, more than 5000 specimens of the pufferfish ("torafugu", Takifugu rubripes) cultured in such manners for 1-3 years were collected from several locations in Japan during 2001-2004, and toxicity of their livers and some other parts was examined according to the Japanese official mouse assay method for TTX. In addition, typical specimens were submitted to LC/MS analysis. The results showed that all the livers and other parts tested were 'non-toxic' in both of the mouse assay (less than 2 MU/g) and LC/MS analysis (less than 0.1 MU/g). Thus, it is undoubtedly confirmed that pufferfish are intoxicated through the food chain, and non-toxic pufferfish can be successfully produced by netcage or land culture. The livers from these fish can be used with safety as a Japanese traditional food "fugu-kimo" (puffer liver).

A new version of the Meteorological Research Institute (MRI) coupled general circulation model MRICGCM2 (MRI2.3) is developed and compared with the previous version (MRI2.0). The cloud scheme includes diagnostic function for cloud amount separately specified for convective and layer clouds, which is one of the major modifications contributing to the improved model performance. MRI2.3 exhibits better agreement with the observations in many aspects of present-day climate simulations, including the global energy budget, meridional distributions of shortwave and longwave radiation at the top of the atmosphere, and geographical distributions of surface air temperature and precipitation. The effective climate sensitivity of each version is evaluated based on an experiment with a transient (1%/year) increase of carbon dioxide concentration. The effective climate sensitivity of MRI2.3 (2.9 K) is about twice that of MRI2.0 (1.4 K). The change in the cloud-forcing response, particularly for shortwave cloud forcing, is essential for increasing climate sensitivity. A difference in tropical low-level clouds over the subsidence regions contributes significantly to the difference in cloud-forcing changes in response to a climate change. Analyses based on circulation regimes, defined by the vertical velocity at the mid-troposphere, suggest that the cloud-forcing response in the tropics is controlled more by thermodynamic characteristics, such as changes of the stability in the lower troposphere, rather than by large-scale circulation changes, such as a change in the subsidence strength.

リンゴ‘ふじ‘と‘恵’を供試して着果程度と種子の有無の処理を施し, 果台枝頂芽の糖類およびGA含量と花芽形成との関係について検討した.果台枝頂芽における翌年の着花率は, 不着果および無種子果着果に比べ, 有種子着果の方が低かった. 果台枝頂芽の新鮮重は, 6月初めにどの処理も同じだったが, 7月初めに無種子が有種子の着果より大きくなった. 果台枝葉の同化産物の果台枝頂芽への分配は, 種子よりも果実の存在によって影響され, 果そう当たりの果実乾物重が大きいほど減少した. また, 6月初めにおける果台枝頂芽の糖類含量も, 着果の程度が強くなるほど減少した. 着果により頂芽内で減少する糖類は, ソルビトールとグルコースで, スクロースは変化しなかった. 6月初めにおける果台枝頂部のGA含量は, 不着果と無種子1果の果台枝の方が有種子1果と3果の果台枝より低く, 着果よりも種子の存在により増加した.

Tetrodotoxin (TTX) was localized as brown color in different tissues of an undescribed species of the nemertean genus Cephalothrix (phylum Nemertea) and a turbellarian Planocera reticulata (phylum Platyhelminthes) on light microscopy by means of a monoclonal anti-TTX antibody. In the Cephalothrix sp., TTX was recognized in the vesicles apically arranged in the bacillary cells in the epidermis, basal lamina, the granular cells in the proboscis epithelium, rhynchocoel epithelium, and the vesicles in the basal portion of the intestinal wall near the blood vessels and rhynchocoel. The excretory system and the ovum also showed positive reaction of TTX antigen-antibody. On the other hand, the hermaphrodite flatworm P. reticulata exhibited TTX antigen-antibody complex only in their ovum. To our knowledge, this is the first experimental effort on micro-distribution of TTX in invertebrates.

鉢植えのリンゴ幼樹を用いて，シンク・リミット状態における光合成速度低下の機構について解析した．3日間の連続明期（CL）処理によって，光合成速度は38％，気孔コンダクタンスは58％，細胞間隔CO2濃度は9％，それぞれ低下した．同時に葉内デンプン含量は対照樹の2.8倍に増加した．従って，CL処理によって，リンゴ幼樹はシンク・リミット状態になった．しかし，その後の1日の連続暗期（CD）処理によって，光合成速度，気孔コンダクタンス及び細胞間隔CO2濃度はほぼ回復した．同時に，葉内デンプン含量は大きく減少し，対照樹とほぼ同じになった．従ってその後のCD処理によって，リンゴ幼樹はシンク・リミット状態から解除された．3日間CL処理した樹における光合成A-Ci曲線の初期勾配は対照樹に比べて17％低下した．その後の1日CD処理により，A-Ci曲線の初期勾配は完全に回復した．しかし，3日間CL処理した樹のRuBPcase活性及び量はあまり変化しなかった．これらの結果より，CL処理によってシンク・リミット状態に置かれたリンゴ幼樹の光合成速度の低下，すなわち，カルボキシレーション効率の低下は，RuBPcase活性の低下よりは，むしろ気孔開度の低下に起因していたことが推察される．

The involvement of ethylene in the pedicel in preharvest fruit drop and the relationship between ethylene in the pedicel and its production in the flesh and the seed were investigated in 'Tsugaru' apple. The induction of pedicel abscission was achieved by the injection of ethylene with a syringe, whereas it was inhibited by 2, 5-norbornadiene (NBD), an antagonist of ethylene action. The injection of ethephon into the fruit core, or the spray on the bourse resulted in increasing ethylene content in the pedicel and subsequent fruit abscission. The treatment with aminoetoxy-vinylglicine (AVG) of the fruit core, the inhibitor of ethylene synthesis, reduced the fruit abscission and ethylene content in the pedicel. Ethylene production of the seed and the flesh, and its content in the pedicel in 'Tsugaru' greatly increased before the rapid increase in fruit drop. Fruit of 'Jonagold' usually do not exhibit preharvest drop, the ethylene production and ethylene content are low; they increased little before harvest. Therefore, ethylene likely originates in the flesh and seeds and is translocated to the pedicel where it acts to induce fruit abscission.

During 1990 to 2003, the toxicity of the liver in 4,515 specimens of the puffer fish Takifugu rubripes (torafugu) cultured in netcages or on land were investigated by means of mouse bioassay and liquid chromatography-mass spectrometry (LC/MS). Other tissues (skin, muscles, gonads, etc.) were also investigated in some of them. All the livers and other parts examined were found to be non-toxic. The peak corresponding to tetrodotoxin (TTX) was not detected in the samples by LC/MS analysis for TTX (< 0.1 MU/g). These results show that puffer fish fed on a non-toxic diet in netcages do not become intoxicated.

A high-performance anion-exchange liquid chromatography system was constructed to identify sugar phosphates and nucleotides involved in photosynthetic metabolism. First sugar phosphates and nucleotides were separated by a gradient elution with boric acid and sodium phosphate, then they were detected by a fluorescence detector (as fluorescent derivatives with arginine) and UV detector, respectively. Eight authentic sugar phosphates and 11 authentic nucleotides could be analyzed using the system. The applicability of the system to the determination of the corresponding sugar phosphates and nucleotides in extracts from only five soybean leaf discs (8.95 cm2) was shown.

A novel sulfotransferase (O-ST), which transferred the sulfate group of 3′-phosphoadenosine 5′-phosphosulfate (PAPS) to O-22 of 11-α,β-hydroxy saxitoxin (STX) and produced GTX2 + 3, was purified to homogeneity from the cytosolic fraction of clonal-axenic vegetative cells of the toxic dinoflagellate Gymnodinium catenatum GC21V. After four purification steps, including affinity chromatography and anion exchange chromatography, the enzyme was purified 500-fold and the yield was 4%. On affinity chromatography with a PAP-agarose column, O-ST was observed in the bound fraction, and N-ST specific to N-21 of STX and GTX2 + 3 was found in the unbound fraction. The molecular mass of the purified enzyme was determined by sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) to be 65 kDa. Gel filtration chromatography showed a native molecular mass of 67 kDa, indicating that O-ST is a monomeric enzyme. The enzyme was optimally active at pH 6.0 and 35°C. O-ST did not require metal cations for its activity. O-ST required PAPS as the sole source of sulfate. O-ST transferred a sulfate group from PAPS to only O-22 of 11-α,β-hydroxy STX and not to N-21 of these toxins. These observations suggested that two ST, N-ST and O-ST, participate in the sulfation of PSP toxins.

Intra-tissue distribution of tetrodotoxin (TTX) in the skin of larva, juvenile, and adult Japanese newt Cynops pyrrhogaster was investigated by means of a monoclonal antibody-based immunoenzymatic technique. In the investigation, TTX was localized at immature glands in juvenile, and at the granular cells composing of granular and mixed glands in adult specimens under a light microscope. No specific stain was recognized in larval section. A duct like structure extending from the granular gland towards super epithelial layer was visualized in the toluidine blue treated skin section of adult newt. When stimuli by wiping with gauze ('handling stimulus') were given, C. pyrrhogaster was found to secrete an applicable amount of TTX and 6-epiTTX from the skin, suggesting that the newt has a granular gland of TTX to secrete it towards the body surface possibly as a biological defensive agent.

ギ酸カルシウム剤によるリンゴの摘花効果について，結実に及ぼす影響と作用機作について検討した．ギ酸カルシウム剤の0.33-1％液を満開後に散布した場合，結実率の低下が認められた．ギ酸カルシウム剤は，柱頭に傷害を与え，また，花粉管の伸長を阻害することから，これらのことが結実を阻害する原因と考えられた．処理濃度に関しては，0.5％でも柱頭の傷害と花粉管の伸長阻害が認められたが，安定的な効果と実際の結実率から，1％での散布が効果的であると考えられた．

金沢大学理工研究域環境デザイン学系, To evaluate future changes in storm surge caused by global warming, dynamical downscaling was conducted using the Weather Research and Forecasting model for Typhoon Vera under present- and future-climate conditions and storm surge simulation using the Coupled Model of Surge, Wave, and Tide. The present-climate experiment entailed dynamical downscaling using data from the Japanese 55-year Reanalysis project as the initial and boundary conditions, and the future-climate experiments entailed downscaling considering future changes simulated through sea-surface temperature ensemble experiments using the Meteorological Research Institute Atmosphere General Circulation Model. The characteristics of the downscaled typhoon agreed well with the Best Track, and the future changes in the typhoon characteristics were as follows: intensification of the central pressure, delayed decline in the high-latitude area, and westward track migration. Present-climate storm surge simulation executed using these downscaling results after correcting for the track error agreed with the observed surge, but the storm surges under future-climate conditions were underestimated because of differences in the typhoon track and surface roughness. Storm surge simulations were conducted using an empirical typhoon model; the results suggest a storm surge of 26cm (average of the ensemble) at Nagoya Port, which is located in the innermost region of Ise Bay. © 2017 World Scientific Publishing Company., Embargo Period 12 months

A feeding experiment of TTX-containing diet was conducted using the small scavenging marine snails Pliarcularia globosa and Reticunassa festiva. Seventy-five specimens of each species were divided into 15 groups of 5 individuals, of which 3 groups were directly submitted, without feeding, to toxin quantification as described below. TTX was not detected. Each of the remaining 12 groups was accommodated in a plastic case (80×70×40 mm) filled with seawater, and fed for 24 hours with ovary tissue (0.1 g) of the pufferfish Takifugu vermicularis, whose TTX content had previously been determined. Then the seawater was exchanged for fresh seawater, the snails were reared for 4 days without feeding, and then the seawater was changed again. This feeding/rearing cycle (5 days) was repeated 8 times, and 3 groups were sampled every 2 cycles. The combined viscera and combined muscle of each group were each extracted with 0.1% aqueous acetic acid, and then TTX was quantified by liquid chromatography-mass spectrometry. The estimated amount of ingested TTX was calculated by multiplying the difference between the amounts of ovary tissue supplied and remaining by the toxin content (122-126 MU/g). Similar mean values of 5.1 MU/group/cycle in P. globosa and 5.3 MU/group/cycle in R. festiva were obtained. Toxin content (TTX amount per gram of tissue) and toxin amount (TTX amount per group) during the experimental period were 0.23-2.85 MU/g and 0.05-0.96 MU/group, respectively, in P. globosa viscera. Both values increased markedly from the 2nd cycle to the 6th cycle. In contrast, no such increase in toxin content/amount was observed throughout the experimental period in P. globosa muscle (

Haloalkaliphilic strains JCM 19037, JCM 19038, JCM 19039, and JCM 19055, closely related to Geomicrobium sediminis , were isolated from aquatic samples, and their draft genome sequences were determined. The genome information of these four strains will be useful for studies of their physiology and ecology.

Vibrio sp. strains JCM 18905 and JCM 19053 were isolated from a tetrodotoxin (TTX)-bearing scavenging gastropod, and Vibrio sp. strain JCM 18904 was isolated from a sea cucumber. All these are closely related to Vibrio alginolyticus . Their comparative genome information is useful for studies of TTX production in bacteria.

Four Psychrobacter strains, JCM 18900, JCM 18901, JCM 18902, and JCM 18903, related to either Psychrobacter nivimaris or Psychrobacter cibarius , were isolated from frozen marine animals. The genome information of these four strains will be useful for studies of their physiology and adaptation properties to frozen conditions.

In reservation radio packet transmission protocols, non-collision packet reservation multiple access (NC-PRMA) is known to be able to transmit packets without any collision and to attain higher throughput than packet reservation multiple access (PRMA). However, so far only NC-PRMA in voice-only traffic has been studied. In this paper we evaluate NC-PRMA in integrated voice and data traffic. First, considering data terminals, we formulate an equilibrium point analysis by guaranteeing the number of slots for data packet transmission in one frame. The number is decided according to the number of terminals. Next, we evaluate the throughput and the voice packet dropping probability by theoretical analysis and computer simulation. It is shown that in integrated voice and data traffic NC-PRMA attains better throughput and voice packet dropping probability than PRMA. © 2001 Scripta Technica, Electron Comm Jpn Pt 1, 84(12): 13–21, 2001

A sulfotransferase (ST) specific to N-21 of saxitoxin (STX) and gonyautoxin 2+3 (GTX2+3) designated as N-ST was purified to homogeneity from the cytosolic fraction of clonal-axenic vegetative cells of the toxic dinoflagellate Gymnodinium catenatum Graham GC21V, which causes paralytic shellfish poisoning. The enzyme transferred a sulfate group from 3'-phosphoadenosine 5'-phosphosulfate (PAPS) to N-21 in the carbamoyl group of STX and GTX2+3 to produce GTX5 and C1+2, respectively. The molecular mass of the purified enzyme was determined by SDS-PAGE to be 59 kDa. Gel filtration chromatography showed a native molecular mass of 65 kDa, indicating that the N-ST is a monomeric enzyme. The N-ST was specific to only N-21 of STX and GTX2+3, and O-22 sulfation was not observed. Moreover, the N-ST was not active toward neo STX and GTX1+4, which differed from STX and GTX2+3, respectively, in only N-1 hydroxylation. When various compounds previously reported to be substrates for STs in other organisms and paralytic shellfish poisoning toxins other than STX and GTX2+3 were added to the reaction mixture, N-ST activity was not decreased. The enzyme required PAPS as the sole source of sulfate. The enzyme was optimally active at pH 6.0 and 25° C, and its activity was enhanced by Mg 2 + and Co 2 + . The K m values of the N-ST for STX and GTX2+3 were 16.1 μM and 29.8 μM, respectively.

The influence of maturing and ripening on phenylalanine ammonia-lyase (PAL) activity and anthocyanin accumulation was examined using bagged, non-bagged and shaded ‘Jonathan’ ( Malus domestica ) apples. Bagged fruit were covered with paper bags from mid-June at an early stage of fruit growth. Shaded apples were insulated from sunlight by newspaper at the beginning of colouring (middle September). The apples were harvested at different maturity stages and were irradiated with UV+white light for 96 h at 15°C after which anthocyanin content and PAL activity were measured. In non-bagged and shaded apples, anthocyanin accumulation and maximal PAL activity increased as the apples developed from the immature to the initial ripe stage, then decreased at full ripe stage. A positive linear relationship between the maximum PAL activity and the amount of anthocyanin accumulated suggested that the change in PAL activity is involved in the change of anthocyanin accumulation. In the bagged apples in the immature stage, anthocyanin accumulation and peak PAL activity after irradiation was higher than that in non-bagged apples. However, as the apples ripened, anthocyanin accumulation was less than for less mature fruit, even though PAL activity was relatively high. Therefore, PAL is not the only regulating factor for anthocyanin accumulation in bagged mature and ripe fruit.

Relative light intensities in an apple (Malus domestice Borkh.) tree canopy were determined by measuring light quantity : photometrically (illuminance, lx), radiometrically (radiation, W·m-2), and in quantum terms (photosynthetic photon flux, μmol·m-2·s-1). There was a strong positive correlation between relative illuminance and relative photosynthetic photon flux, measured on an overcast day. Relative photosynthetic photon flux was, however, 6.0% higher than relative illuminance. A strong correlation was also found between relative illuminance and relative cumulative photosynthetic photon for one day ; the latter was higher by 6.7% on an overcast day and 6.8% on a clear day. There was a strong positive correlation between the relative cumulative photosynthetic photon and the relative cumulative amount of global solar radiation for one day, while that of relative cumulative photosynthetic photon was 11% lower than relative cumulative amount of global solar radiation.

Polyoxyethylene alkyl esters, which are surface-active agents, were chemically synthesized from fatty acids (C12-C18) on reaction with different moles of polyethylene oxides, and were tested for effectiveness against the toxic raphidophytes Chattonella marina (Subrahmanyan) Hara & Chihara and C. antiqua (Hada) Ono. The synthetic surfactants destroyed cultured cells from these two species. Although the synthetic surfactants also exhibited ichthyotoxicity, this was lowered by increasing the molarity of ethylene oxide (EO) in alkyl ester molecules. Young yellowtail, Seriola quinqueradiata Temminck & Schlegel, survived exposure to C. marina (5000-5500 cells mLT−1) or C. antiqua (3000-3500 cells mL−1) cultures with the addition of 4-5 p.p.m. oleyl ester EO 14, but died within an hour without the addition of this surfactant.

A new component of paralytic shellfish poison was isolated from a Bangladeshi freshwater puffer Tetraodon cutcutia. Its structure was deduced to be carbamoyl-N-methylsaxitoxin based on electrospray ionization mass spectrometry, [1H] NMR, and conversion experiments.

The effects of temperature, salinity, light intensity and pH on the growth and morphology of Chattonella marina (Subrahmanyan) Hara & Chihara were examined. Optimal growth was observed at temperatures of 20-25°C, salinities of 20-30%o, light intensities of 60-140 μE m−2 s_1 and pH 7.5-8.5. Growth did not occur at temperatures below 15°C or above 30°C, and at salinities below 10%o. The morphology (shape) of the cells was strongly affected by temperature. At 20°C and 25°C, the population occurred mostly in a spindle-like form, whereas at 10°C, 90% of the cells became spherical within 10 days of inoculation and stationary phase cultures consisted entirely of spherical cells. Morphology was also markedly affected at 30°C. The number of spindle-like cells was highest at 20-30%o and was less at lower salinities. Light intensity and pH did not influence morphology markedly under the range of light intensities (20-180 μE m −2 s-−1) and pH (6.5-8.5) tested.

The effects of five methods of girdling and bark inversion on tree growth and fruit quality in 'Megumi' apple (Malus domestica Borkh.) were compared. Bark inversion treatments were : BI-100 (5 cm bark ring was removed from the trunk and replaced in an inverted position), BI-90 (90% of a 5 cm bark ring was removed from the trunk and replaced in an inverted position, leaving a vertical 10% strip of the bark intact), bark exchange ; B-EX (90% of a 5 cm bark ring was removed from the trunk and exchanged with 'Hokuto' bark, leaving a vertical 10% strip of the bark intact), girdling ; G (90% a 5 cm bark ring was removed from the trunk leaving a vertical 10% strip of the bark intact) and G-N (90% a 5 cm bark ring was removed from the trunk, then that bark was reattached in a normal position, leaving a vertical 10% strip of the bark intact). All treatments, except G-N and B-EX significantly reduced the growth of the trunk's girth below the treatments, but had no effects on trunk growth above the treatments. The shoot length was significantly shorter and the spur/shoots ratio was significantly higher in BI-100 than in those of other treatments. Flowering the following spring was significantly increased by all treatments. Chlorophyll concentration in the leaves of BI-100 was lower than that of the control trees at one month after the treatment ; it decreased after three months in all treatments except B-EX. Soluble solids content in the fruit of BI-100 was the highest, followed by G, BI-90, B-EX, and G-N, and the control in decreasing order. Sugars and sorbitol content on a fresh weight basis were significantly higher in BI-100 than in BI-90, G-N and control fruits. But on a dry weight basis, they were lower in the treated fruits than in the control fruit because in the treated fruits had lower water content than the control fruit. Fruit firmness and fruit size were influenced little by the treatments. All treatments reduced calcium concentration in the fruit flesh. Soluble solids content in the fruits of BI-100 and BI-90 in following year was significantly higher than that of other treatments. These results show that girdling and bark inversion improved the eating quality of the fruit by increasing soluble solids content while lowering water and calcium content.

In April 1995, an unusual large-scale red tide of Heterosigma akashiwo (Hada) Hada occurred, causing massive fish kills in Kagoshima Bay, Japan. Four neurotoxic components, HaTx-i, HaTx-iia, HaTx-iib and HaTx-iii, which corresponded to brevetoxin components. PbTx-2. PbTx-9, PbTx-3 and oxidized PbTx-2, were inferred from analysis of Heterosigma red tide toxins on TLC and HPLC.