[Forecast of total pollen counts of sugi (Cryptomeria japonica) from the amount of male flower development and the revised total pollen counts].

We have successfully forecast the total pollen counts of sugi (Cryptomeria japonica) since 1996 by the amount of male flower development. The amount of male flower development was observed at 11 forests in the Tanba Mountains and 10 forests in the Chugoku Mountains depending on both in Hyogo Prefecture. The amount of male flower development on each tree was assigned to one of five classes by the number of male flowers per spring. After a large harvest of male flowers, the production of male flowers declined in the following years, especially at high altitudes. It was also followed by a decrease in the number of airborne pollen grains in the later pollen season. According to an analysis of weather conditions, total pollen counts were correlated with the high temperature between July 6 and 20 and the total pollen counts of the previous season. However, the amount of male flower development was the most significant indicator for forecasting total pollen counts. Decrease in total pollen counts due to abnormal weather during the pollen season was correlated with discrepancies in forest flowering time according to observations made in the Rokko Mountains. Increase in total pollen counts was connected by a development of the sugi forest areas. Twenty percent of mature sugi forests from 1992 which showed an annual increase were associated with an increase in total pollen counts. The accuracy of the forecast was improved by revising the total pollen counts for weather conditions during the dispersion stage, a decrease in the production of male flowers at high altitude, and an increase in the production of male flowers connected by a developing forest areas.

[The increase and decrease of the total pollen counts of Sugi (Cryptomeria japonica) due to abnormal weather during pollen scattering season].

We investigated the changing total number of airborne pollen grains of Sugi (Cryptomeria japonica) due to abnormal weather during pollen scattering season. The pollen season was divided into 7 periods by the discrepancies in forest flowering time for observations. The observation forests were located at an altitude of 150 m, 220 m, 350 m, and 500 m, and 800 m in the Rokko mountains. These were located at equal spaces, when altitude was taken in the logarithm. The distribution percentage of pollen counts from 1993 to 1998 showed an almost normal distribution level. This was demonstrated by the Log-Normal Probability paper, with a middle level altitude of a 350 m forest. We could estimate the relative rate of 5 different altitude forests against the corresponding amount of pollen as shown under, 0.09 at 150 m forest, 0.34 at 220 m forest, 0.31 at 350 m forest, 0.16 at 500 m forest, 0.10 at 800 m forest. The percentage of pollen counts at the 500 m forest in 1994 and at the 350 m forest in 1995 were decreased from 95% confidence interval. We regarded the decrease in the percentage of pollen counts during these two time, as a cause weak wind velocity and wrong wind direction in Tanba mountains. It was shown that the method for dividing pollen season in different observation forests in which altitude differs, will be useful for pollen forecasts and the pollen source countermeasure.

[A relationship between birch pollen and meteorological factors during the past four years and pollen survey in Sapporo in 1997].

It is well known that grass pollinosis has been the most representative pollinosis in Hokkaido prefecture, Japan, However, it is also well known that birch (Japanese white birch, Betula platyphylla var. japonica) pollinosis is gradually increasing, which is marked especially in Sapporo and its neighborhood. We analyzed a relationship between the birch pollen count and meteorological factors statistically. Moreover, the principal airborne pollen counts in Sapporo in 1997 were assessed and compared with the previous pollen data. As a results of this study, it was showed a close relationship between the annual amounts of birch pollen and meterological factors of the year before, especially in May and June might be important. Moreover, there is a strong negative correlation between the birch pollen count and humidity, which seems to affect bringing up flower buds. As for the principal airborne pollen counts, some kinds of tree pollen, including birch pollen, were observed from the end of March, followed by grass (Gramineae) pollen in June and mugwort (Artemisia) pollen from the end of August, respectively. The annual amounts of grass pollen showed a decreasing trend.

Inhibition by acetylsalicylic acid, a cyclo-oxygenase inhibitor, and p-bromophenacylbromide, a phospholipase A2 inhibitor, of both cirrhosis and enzyme-altered nodules caused by a choline-deficient, L-amino acid-defined diet in rats.

Effects of inhibitors of arachidonic acid (AA) metabolism on the development of fatty liver, cirrhosis, glutathione-S-transferase placental form (GST-P)-positive nodules and the generation of 8-hydroxydeoxyguanosine (8-OHdG) and thiobarbituric acid-reactive substances (TBARS), caused by a choline-deficient, L-amino acid-defined (CDAA) diet, were examined in male Fischer 344 rats by feeding CDAA diets supplemented with the inhibitors for 12 and 30 weeks. Acetylsalicylic acid (ASA) (at doses of 0.1 and 0.2%) and p-bromophenacylbromide (BPB) (0.1 and 0.2%) were used as inhibitors of, respectively, cyclo-oxygenase and phospholipase A2, and quercetin (QU) (0.75 and 1.5%) and nordihydroguaiaretic acid (NDGA) (0.1 and 0.2%) as inhibitors of lipoxygenase. None of the inhibitors affected the development of fatty liver caused by the CDAA diet. ASA at a doe of 0.2% almost completely prevented the appearance of cirrhosis, GST-P-positive nodules, 8-OHdG and TBARS in seven out of 11 (63.7%) rats. BPB at a dose of 0.2% also exerted inhibitory effects on all of these lesions but to a lesser extent than ASA. QU and NDGA exerted inhibitory effects limited to the GST-P-positive nodule case. The results indicate that a perturbed AA metabolism, particularly of the cyclo-oxygenase pathway, derived secondarily from depletion of labile methyl groups or phosphatidylcholine, might play key roles in the cirrhosis, hepatocarcinogenesis and oxidative stress caused by a CDAA diet. The results also indicated a possible involvement of the lipoxygenase pathway in hepatocarcinogenic processes.

Identification of two isoforms of mouse neuropeptide Y-Y1 receptor generated by alternative splicing. Isolation, genomic structure, and functional expression of the receptors.

Two cDNA clones homologous with human neuropeptide (NP) Y-Y1 receptor have been isolated from a mouse bone marrow cDNA library. One was thought to be the cognate of the human NPY-Y1 receptor, termed Y1 alpha receptor, and the other form, termed Y1 beta receptor, differed from the Y1 alpha receptor in the seventh transmembrane domain and C-terminal tail. Analysis of the mouse genomic DNA showed that both receptors originated from a single gene. The different peptide sequences of the Y1 beta receptor were encoded by separate exons, hence, these receptors were generated by differential RNA splicing. High affinity binding of [125I]NPY to each receptor expressed in Chinese hamster ovary (CHO) cells and sequestration of [125I]NPY after binding to each receptor were observed. In the CHO cells expressing the Y1 alpha receptor, intracellular Ca2+ increase, inhibition of forskolin-induced cAMP accumulation, and mitogen-activated protein kinase (MAPK) activation were observed by stimulation of NPY, and these responses were abolished by pretreatment with pertussis toxin. Since wortmannin completely inhibited NPY-elicited MAPK activation, we speculate that wortmannin-sensitive signaling molecule(s) such as phosphoinositide 3-kinase may lie between pertussis toxin-sensitive G-protein and MAPK. In contrast, these intracellular signals were not detected in CHO cells expressing the Y1 beta receptor. Northern blots and reverse transcriptase-polymerase chain reaction analyses indicated that the Y1 alpha receptor was highly expressed in the brain, heart, kidney, spleen, skeletal muscle, and lung, whereas the Y1 beta receptor mRNA was not detected in these tissues. However, the Y1 beta receptor was expressed in mouse embryonic developmental stage (7 and 11 days), bone marrow cells and several hematopoietic cell lines. These results suggest that the Y1 beta receptor is an embryonic and a bone marrow form of the NPY-Y1 receptor, which decreases in the expression during development and differentiation.

[Epidemiologic study of Alnus sieboldiana Matsumura (alder) pollinosis in Ashiya city].

Alnus sieboldiana has been planted widely on denuded sites in the Rokko mountains. Its pollination season is in the latter half of that of Japanese cedar. This epidemiologic study was carried out in Ashiya in the 1991 spring hay fever season. The subjects were 532 female residents chosen at random, who had been living there more than ten years. There was an evident relation between the airbone alder pollen count and the prevalence of alder pollinosis. In the mountain town most severely inundated with alder pollen (977/sq. cm/year), the prevalence rate of alder pollinosis alone or both alder and cedar pollinosis was 26.1%. In the flat area 5 km far from south of the mountain town, where aribome pollen count was 386/sq.cm/year, the prevalence rate of alder pollinosis was 4.3%. The heavy traffic main road pass through the flat area, thus the air pollution was significantly strong in the flat area more than in the mountain town. However, we couldn't find adjuvant effect of air pollution on the alder pollinosis, which was often reported about Japanese cedar pollinosis.

Lack of toxicity/carcinogenicity of monosodium succinate in F344 rats.

The toxicity/carcinogenicity of monosodium succinate, a food additive, was examined in F344 rats. The oral LD50 was greater than 8 g/kg body weight. In a 13-wk subchronic oral toxicity study, the only toxicological finding was suppression of body-weight gain in groups given greater than or equal to 2.5% monosodium succinate in the drinking-water. Histological examination revealed no toxic lesions specifically caused by the compound in any organs of any of the treated rats. The maximum tolerated dose was determined to be 2-2.5% on the basis of body-weight depression. In a long-term (2-yr) toxicity/carcinogenicity study, monosodium succinate was given ad lib. in drinking-water (distilled water) at levels of 0, 1 or 2% to groups of 50 male and 50 female rats. No toxic lesion specifically caused by long-term administration of monosodium succinate was detected. No dose-related increase was found in the incidences of tumours in any organ or tissue except for C-cell tumours of the thyroid gland of females. The incidence of these tumours in females given the 2% dose was higher than that in controls but not significantly so, and a positive trend for this tumour was noted in females. C-Cell tumour is one of the most commonly observed spontaneous tumours in ageing female rats of this strain and occurs at a variable incidence. There was no difference between the female control and treated groups in the incidence of preneoplastic change of the thyroid gland. Furthermore, the incidence of C-cell tumours in the female control group was lower than that in our historical controls. It is concluded that the increase in C-cell tumours in the female high-dose group and the detection of a positive trend for this tumour in females were probably a function of experimental variability and were not related to treatment. The results indicate that monosodium succinate had neither toxic nor carcinogenic activity in F344 rats when it was given continuously at levels of 1 or 2% in the drinking-water for 2 yr.

The role of hydrogen peroxide in basophil histamine release and the effect of selected flavonoids.

Studies on hydrogen peroxide (H2O2)-induced histamine release from human basophils indicate that H2O2 is a weak stimulus of histamine release, that the release process is Ca2+ and energy-dependent, and that histamine release is not influenced by theophylline (in keeping with previous observations with rat mast cells). Low concentrations of H2O2 appeared to augment and high concentrations to inhibit histamine release induced by anti-IgE. However, the inhibitory effect of high concentrations of H2O2 were completely abrogated by catalase, which destroys H2O2, and thus indicates that basophils retain immunologic responsivity and are not irreversibly effected by high concentrations of H2O2. Leukocyte suspensions relatively enriched in monocytes, lymphocytes, basophils, neutrophils, and neutrophils plus eosinophils were prepared by Percoll-gradient centrifugation. Anti-IgE stimulated H2O2 formation only in the fraction richest in basophils. Opsonized zymosan, on the other hand, stimulated H2O2 generation in both the basophil and monocyte fractions, indicating activation of both monocytes and basophils by this stimulus. Mixtures of basophil-containing leukocyte suspensions plus purified neutrophils and opsonized zymosan stimulated histamine release in proportion to concomitant generation of H2O2. Addition of catalase reduced histamine release under these conditions, whereas scavengers of other toxic oxygen derivatives (superoxide dismutase, alpha-tocopherol, D-mannitol) had little or no effect on histamine release. These findings suggest that neutrophil-derived H2O2 can cause basophil histamine release in mixed populations of activated leukocytes. Three naturally occurring flavonoids, quercetin, apigenin, and taxifolin (dihydroquercetin) were examined for their effect on anti-IgE-induced histamine release and H2O2 generation in basophil-containing leukocyte suspensions.(ABSTRACT TRUNCATED AT 250 WORDS)