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51.
The chemistry of the exocrine glands of three species of the small and little-known ant subfamily Cerapachyinae has been examined for the first time. The mandibular glands of Cerapachys jacobsoni contained acetophenone and skatole, but some individuals contained, in addition, 4-methyl-3-heptanone and 3-octanol. The mandibular glands of the new species, presently known as Cerapachys sp. 15 of FI contained 4-methyl-3-heptanone, as the major substance but also 4-methyl-3-heptanol, methyl 6-ethylsalicylate, and traces of 4,5-dimethyl-4-hexen-3-one and homomanicone. The Dufour glands of C. jacobsoni contained a mixture of higher aldehydes, acetates and other esters, with a small amount of hydrocarbons, all in the range C11–C20. The Dufour glands of Cylindromyrmex whymperi contained a mixture of long-chain epoxides, the second ant species to display them. The sternal glands of C. whymperi contain a recruitment pheromone, but only partial identification of the contents was possible. The venom glands of all three species were devoid of volatile material. The Dufour glands of Cerapachys sp. 15 of FI and the mandibular glands of C. whymperi had no detectable volatile contents.  相似文献   
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During a screening programme for new medical agents, many aqueous extracts from 59 species of seaweed were found to possess bioactivity against murine immunocytes. Thirty-eight extracts (8 green, 12 brown, 18 red algae) showed suppressive effects on the mitogenic response. Furthermore, 16 extracts (2 green, 6 brown, 8 red algae) suppressed the production of Interleukin 1 (1L-1) from murine macrophage. Using the murine mixed lymphocyte reaction assay, suppressive effects were observed in 4 red algae, but none in green or brown algae. Nine seaweed extracts suppressed the production of secondary antibody (IgG, IgM). Extracts of 3 red algae suppressed strongly the proliferation of bone marrow cells, but 2 other red algae caused stimulation above 200%. This is apparently the first report showing immunosuppressive activity from marine algae.  相似文献   
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Mean egg cluster size of Luehdorfia puziloi yessoensis varied among habitats. The mean egg cluster size tended to be large when abundance of the larval food leaves expressed as the fresh weight of leaves per unit area at a given habitat was high. Since this variation was observed among closely located study plots (butterflies can easily move between study plots), the egg cluster size variation among habitats is likely to be a result of flexible response by females to varying food abundance for larvae.  相似文献   
54.
It has been reported that a functional fat-taste receptor, GPR120, is present in chicken oral tissues, and that chickens can detect fat taste in a behavioral test. However, although triglycerides need to be digested to free fatty acids to be recognized by fat-taste receptors such as GPR120, it remains unknown whether lipase activities exist in chicken oral tissues. To examine this question, we first cloned another fat-taste receptor candidate gene, CD36, from the chicken palate. Then, using RT-PCR, we determined that GPR120 and CD36 were broadly expressed in chicken oral and gastrointestinal tissues. Also by RT-PCR, we confirmed that several lipase genes were expressed in both oral and gastrointestinal tissues. Finally, we analyzed the lipase activities of oral tissues by using a fluorogenic triglyceride analog as a lipase substrate. We found there are functional lipases in oral tissues as well as in the stomach and pancreas. These results suggested that chickens have a basic fat-taste reception system that incorporates a triglycerides/oral-lipases/free fatty acids/GPR120 axis and CD36 axis.  相似文献   
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Japanese patients with type 2 diabetes mellitus present a different responsiveness in terms of insulin secretion to glucose and body mass index (BMI) from other populations. The genetic background that predisposes Japanese individuals to type 2 diabetes mellitus is under study. Recent genetic studies demonstrated that the locus mapped in macrophage erythroblast attacher (MAEA) increases the susceptibility to type 2 diabetes mellitus in East Asians, including Japanese individuals. MAEA encodes a protein that plays a role in erythroblast enucleation and in the normal differentiation of erythroid cells and macrophages. However, the contribution of MAEA to type 2 diabetes mellitus remains unknown. In this study, to overexpress MAEA in the mouse liver and primary mouse hepatocytes, we generated a MAEA-expressing adenovirus (Ad) vector using a novel Ad vector exhibiting significantly lower hepatotoxicity (Ad-MAEA). Blood glucose and insulin levels in Ad-MAEA-treated mice were comparable to those in control Ad-treated mice. Primary mouse hepatocytes transduced with Ad-MAEA showed lower levels of expression of gluconeogenesis genes than those transduced with the control Ad vector. Hepatocyte nuclear factor-4α (HNF-4α) mRNA expression in primary mouse hepatocytes was also suppressed by MAEA overexpression. These results suggest that MAEA overexpression attenuates hepatic gluconeogenesis, which could potentially lead to improvement of type 2 diabetes mellitus.  相似文献   
58.
Ligand-gated ion channels are important in sensory and synaptic transduction. The PKD1L3-PKD2L1 channel complex is a sour taste receptor candidate that is activated by acids. Here, we report that the proton-activated PKD1L3-PKD2L1 ion channels have the unique ability to be activated after the removal of an acid stimulus. We refer to this property as the off-response (previously described as a delayed response). Electrophysiological analyses show that acid-induced responses are observed only after the removal of an acid solution at less than pH 3.0. A small increase in pH is sufficient for PKD1L3-PKD2L1 channel activation, after exposure to an acid at pH 2.5. These results indicate that this channel is a new type of ion channel-designated as an 'off-channel'-which is activated during stimulus application but not gated open until the removal of the stimulus. The off-response property of PKD1L3-PKD2L1 channels might explain the physiological phenomena occurring during sour taste sensation.  相似文献   
59.
Pyrrospirones A and B have been isolated from unpolished rice cultures of the endophytic fungus Neonectria ramulariae Wollenw KS-246. Their absolute stereostructures (1 and 2) were elucidated through spectroscopic methods using 1D and 2D NMR techniques and chemical transformations, including the modified Mosher's method. The compounds exhibited cytotoxicity and induced apoptosis in human promyelocytic leukemia HL-60 cells.  相似文献   
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