Biological effects of leptospiral lipopolysaccharide to mouse B, T and NK cells

Leptospiral lipopolysaccharides (LPSs) extracted from Leptospira interrogans serovars copenhageni and hebdomadis were tested for the biological effect to mouse B, T and NK cells. Each leptospiral LPS was a potent mitogen for spleen B cells. Activation of the cells was also expressed by polyclonal B cell activation. In contrast, mitogenicity for T cells, induction of interleukin-2 (IL-2) secretion in T cells and increase of tumor-killing activity and chemiluminescence in NK cells were not observed after stimulation with leptospiral LPS. After intravenous injection of leptospiral LPS in mice, the spleen and lymphnodes were examined by histocytochemical technique. Increase of Ig-bearing lymphocytes was recognized while decrease of T cells was observed in the lymphoid organs. Mitogenic response to PHA, Con A and PWM decreased with relation to the T cell depletion. In conclusion, it is apparent that leptospiral LPS possess marked immunological potencies on B cells but not T and NK cells. The biological effects of leptospiral LPS were common ones as LPS but the level was considered to be different from classical LPS such as Escherichia coli LPS.     

Isolation of lymphocytic choriomeningitis virus from wild house mice (Mus musculus) in Osaka Port, Japan.

Lymphocytic choriomeningitis virus (LCMV) was isolated from 14 out of 35 wild house mouse samples captured on two piers of Osaka port in Japan. Four of them were isolated from were isolated from 18 antibody positive mice while 10 were from 17 antibody negative mice. This is the first report of the isolation of LCMV from wild mice in Japan.     

Collagenofibrotic glomerulonephropathy in a cynomolgus macaque (Macaca fascicularis)

Collagenofibrotic glomerulonephropathy (CFGN) is characterized by the deposition of type III collagen within the mesangial matrix and the absence of mesangial cell proliferation. A case of CFGN in a 2.7-year-old female cynomolgus macaque was investigated in the present study. Clinically, the animal was shown to have severe systemic edema along with hypoproteinemia. At necropsy, the kidneys were swollen and pale. The glomerular lesions were characterized by massive diffuse and global accumulation of fibrous materials in the mesangial areas. Neither mesangial cell proliferation nor changes in other organs were found. The fibrous materials were confirmed by the results of immunohistochemical and electron microscopic findings to consist mainly of randomly arranged, curve-shaped, twisted, and entwined type III collagen. This is the first case report of CFGN in nonhuman primates to date.     

Isophorone‐induced light‐independent lipid peroxidation and loss of cell membrane integrity

Isophorone (3,5,5‐trimethylcyclohex‐2‐en‐1‐one) is a plant‐derived volatile compound with strong phytotoxic activity. Here, we aimed to elucidate the mechanism of action of isophorone, and to this end, the effects of isophorone on shoot fresh weight, chlorophyll content, electrolyte leakage, and lipid peroxidation of Lactuca sativa L. and photosynthetic electron transport activity in chloroplast isolated from Spinacia oleracea L. were investigated. Isophorone induced light‐independent decreases in shoot fresh weight and light‐dependent chlorosis. In addition, increased electrolyte leakage and lipid peroxidation occurred under light conditions. However, the inhibitory activity on photosynthetic electron transport was unexpectedly low, and electrolyte leakage and lipid peroxidation were induced even under dark conditions. These results suggest that the inhibition of photosynthetic electron transport is not the main mechanism of action of isophorone and that the phytotoxic effects are mainly due to light‐independent oxidative damage and subsequent loss of cell membrane integrity.     

Acute Effect of Pimobendan and Furosemide on the Circulating Renin-Angiotensin-Aldosterone System in Healthy Dogs

Background: The renin-angiotensin-aldosterone system (RAAS) is activated in states of decreased cardiac output and by certain cardiovascular therapeutic agents, such as loop diuretics and vasodilators.
Hypothesis: Short-term treatment with the inodilator, pimobendan, will not activate the circulating RAAS because its vasodilatory action will be offset by its positive inotropic property, thereby ameliorating RAAS stimulation at the juxtaglomerular apparatus. Furthermore, pimobendan will suppress RAAS activation produced by furosemide.
Animals: Nine healthy laboratory dogs were used in this study.
Methods: Experimental, cross-over study. Dogs were administered pimobendan (0.5 mg/kg q12h) for 4 days followed by furosemide (2 mg/kg q12h) and then, after a wash-out period, a combination of the drugs. Aldosterone : creatinine (A : Cr) was measured at the end of each treatment cycle.
Results: There was no significant increase in the average urinary A : Cr with the administration of pimobendan (control urinary A : Cr = 0.46, standard deviation (SD) 0.33; pimobendan A : Cr = 0.48, SD 0.28). There was a significant increase in the average urinary A : Cr after administration of furosemide (urinary A : Cr = 1.3, SD 0.70) and with the combination of furosemide and pimobendan (urinary A : Cr = 2.9, SD 1.6).
Conclusions and Clinical Relevance: Short-term administration of high-dose pimobendan, does not activate the RAAS in healthy dogs. Pimobendan did not prevent RAAS activation associated with furosemide therapy. These results in healthy dogs suggest that furosemide therapy, with or without pimobendan, should be accompanied by RAAS suppressive therapy.     

Comparison of the nitrogen balance in paddy fields under conventional rice straw application versus cow dung compost application in mixed crop–livestock systems

ABSTRACT

In Japan, rice straw (RS) is commonly incorporated into the soil after harvest to maintain the fertility of paddy soil. However, in mixed crop–livestock systems, RS is collected to feed livestock and then cow dung compost (CDC) is applied to the fields. We found in previous research that CDC supplied more N to the fields than RS, but the soil total N and available N of fields to which CDC was applied were similar to those receiving conventional RS application. To identify the reason for this result, we investigated the N inputs (organic matter, fertilizer, N fixation), N outputs (plant N uptake, N leaching loss), and the N balance of RS application (RS treatment) and RS removal plus CDC application (CDC treatment) in 10 neighboring paddy field pairs in Mamurogawa town, Yamagata Prefecture, Japan. The N fertilizer contributed the highest percentage to total N input, followed by organic matter and N fixation. The amounts of N fertilizer and N fixation in the RS treatment were similar to those in the CDC treatment. CDC contributed significantly more N to the fields than RS, but the total N input was similar between treatments. The N output from plant N uptake and leaching loss were higher in the CDC treatment than the RS treatment, but the difference was not significant. Plant N uptake was the main N output, accounting for 98% of total N output. The N balance was positive and similar between treatments. Therefore, the non-significant differences in total N input, total N output, and N balance between treatments explain the similarity in soil total N and available N.     

Synthesis of benzylaminopyrimidines and their fungicidal activities against wheat brown rust and barley powdery mildew

Members of a new class of fungicide containing benzylaminopyrimidine as a core structure were synthesized and their fungicidal potencies against wheat brown rust, Puccinia recondita, and barley powdery mildew, Erysiphe graminis, were assessed. Among these fungicides, N-(fluoroalkoxy or fluorophenoxybenzyl)-4-pyrimidinamines showed notable preventive activities. The potency of the new pyrimidines was increased when a difluoromethoxy or tetrafluorophenoxy group was introduced at the 4- or 3-position of the phenyl moiety and a methyl or ethyl group was introduced at the benzyl position. Structure–activity relationships are discussed. © 1998 Society of Chemical Industry     

Effects of substituting kraft pulp with corn silage on dry matter intake,ruminal mat formation,rumen fermentation,and rumination activity in non‐lactating cows

The present study examined the effects of substituting kraft pulp (KP) with corn silage (CS) on dry matter intake (DMI), ruminal mat and rumen fermentation characteristics, and rumination. Four non‐lactating, rumen‐cannulated Holstein cows were fed a CS diet comprising 36% grass silage (GS) and 64% CS or a KP diet comprising 36% GS, 57% KP, and 7% soybean meal. DMI was significantly lower in cows fed the KP diet than in those fed the CS diet (p < 0.05), whereas rumination time did not significantly differ between the treatments. Dry matter content in the rumen immediately before and 3 h after feeding was significantly higher in cows fed the KP diet than in those fed the CS diet (p < 0.05). The consistency and thickness of the ruminal mat did not significantly differ between the treatments. The ruminal mean retention time of feed particles tended to be longer in cows fed the KP diet than in those fed the CS diet (p < 0.10). The ruminal digestion rate of KP was comparable to that of GS and CS. Because ruminal mat was formed and rumination was stimulated, KP was considered to have the equivalent physical effectiveness as CS.     

EGFR mutations in lung cancer: correlation with clinical response to gefitinib therapy

Receptor tyrosine kinase genes were sequenced in non-small cell lung cancer (NSCLC) and matched normal tissue. Somatic mutations of the epidermal growth factor receptor gene EGFR were found in 15of 58 unselected tumors from Japan and 1 of 61 from the United States. Treatment with the EGFR kinase inhibitor gefitinib (Iressa) causes tumor regression in some patients with NSCLC, more frequently in Japan. EGFR mutations were found in additional lung cancer samples from U.S. patients who responded to gefitinib therapy and in a lung adenocarcinoma cell line that was hypersensitive to growth inhibition by gefitinib, but not in gefitinib-insensitive tumors or cell lines. These results suggest that EGFR mutations may predict sensitivity to gefitinib.