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Andrea Zuniga Richard J. Stevenson Mehmut K. Mahmut Ian D. Stephen 《Evolution and human behavior》2017,38(1):136-143
Human axillary sweat may provide information pertaining to genetic relatedness and health status. A significant contributor to good health, both in the short and longer term, is a diet rich in fruit and vegetables. In this study we tested whether dietary fruit and vegetable intake, assessed indirectly by skin spectrophotometry (assessing dietary carotenoid intakes) and subjectively by food frequency questionnaire, was associated with more pleasant smelling sweat. Male participants provided axillary sweat samples and dietary information. Female participants then evaluated these samples on several affective, qualitative and psychophysical dimensions. The skin spectrophotometry measure (CIELab b*), indicative of greater fruit and vegetable intake, was significantly associated with more pleasant smelling sweat (with more floral, fruity, sweet and medicinal qualities), independent of sweat intensity. Self-report dietary data revealed that fat, meat, egg and tofu intake was associated with more pleasant smelling sweat, and greater carbohydrate intake with stronger smelling less pleasant sweat. These data parallel facial judgments, in which yellower more carotenoid rich skin, is found to be more attractive. 相似文献
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Ahmet Topal Muhammed Atamanalp Ertan Oruç Muammer Kırıcı Esat Mahmut Kocaman 《Tissue & cell》2014,46(6):490-496
We investigated apoptotic effects and changes in glucose-6-phosphate dehydrogenase (G6PD) enzyme activity in liver and gill tissues of fish exposed to chlorpyrifos. Three different chlorpyrifos doses (2.25, 4.5 and 6.75 μg/L) were administrated to rainbow trout at different time intervals (24, 48, 72 and 96 h). Acute exposure to chlorpyrifos showed time dependent decrease in G6PD enzyme activity at all concentrations (p < 0.05). Immunohistochemical results showed that chlorpyrifos caused mucous cell loss in gill tissue and apoptosis via caspase-3 activation in fish. The present study suggested that chlorpyrifos inhibits G6PD enzyme and causes mucous cell loss in gill and apoptosis in gill and liver tissues. 相似文献
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Makoto Takahashi Masato Obayashi Taro Ishiguro Nozomu Sato Yusuke Niimi Kokoro Ozaki Kaoru Mogushi Yasen Mahmut Hiroshi Tanaka Fuminori Tsuruta Ricardo Dolmetsch Mitsunori Yamada Hitoshi Takahashi Takeo Kato Osamu Mori Yoshinobu Eishi Hidehiro Mizusawa Kinya Ishikawa 《PloS one》2013,8(3)
The human α1A voltage-dependent calcium channel (Cav2.1) is a pore-forming essential subunit embedded in the plasma membrane. Its cytoplasmic carboxyl(C)-tail contains a small poly-glutamine (Q) tract, whose length is normally 4∼19 Q, but when expanded up to 20∼33Q, the tract causes an autosomal-dominant neurodegenerative disorder, spinocerebellar ataxia type 6 (SCA6). A recent study has shown that a 75-kDa C-terminal fragment (CTF) containing the polyQ tract remains soluble in normal brains, but becomes insoluble mainly in the cytoplasm with additional localization to the nuclei of human SCA6 Purkinje cells. However, the mechanism by which the CTF aggregation leads to neurodegeneration is completely elusive, particularly whether the CTF exerts more toxicity in the nucleus or in the cytoplasm. We tagged recombinant (r)CTF with either nuclear-localization or nuclear-export signal, created doxycyclin-inducible rat pheochromocytoma (PC12) cell lines, and found that the CTF is more toxic in the cytoplasm than in the nucleus, the observations being more obvious with Q28 (disease range) than with Q13 (normal-length). Surprisingly, the CTF aggregates co-localized both with cAMP response element-binding protein (CREB) and phosphorylated-CREB (p-CREB) in the cytoplasm, and Western blot analysis showed that the quantity of CREB and p-CREB were both decreased in the nucleus when the rCTF formed aggregates in the cytoplasm. In human brains, polyQ aggregates also co-localized with CREB in the cytoplasm of SCA6 Purkinje cells, but not in other conditions. Collectively, the cytoplasmic Cav2.1-CTF aggregates are sufficient to cause cell death, and one of the pathogenic mechanisms may be abnormal CREB trafficking in the cytoplasm and reduced CREB and p-CREB levels in the nuclei. 相似文献
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Steven Arthurs Jianjun Chen Mahmut Dogramaci A.D. Ali Catherine Mannion 《Biological Control》2011,57(3):202-207
Since its discovery in Florida in 2003, the weeping fig thrips, Gynaikothrips uzeli Zimmerman has spread rapidly throughout the southeastern United States in shipments of ornamental Ficus benjamina L. Concurrently, there have been reports of an invasive anthocorid, Montandoniola confusa (=moraguesi) Streito and Matocq sp. nov., widely associated with G. uzeli populations in landscape plantings of ornamental Ficus spp. We evaluated M. confusa and a commercially available anthocorid, Orius insidiosus Say, as biological control agents of G. uzeli. Prey preference studies revealed that eggs were the numerically preferred host stage for both predator species (representing 92% and 94% of all prey taken in ‘no choice’ and ‘choice’ tests, respectively). Females of both predator species consumed significantly more eggs than males (83–91 versus 25–35 per 48 h period, respectively), and (in the absence of eggs) also more larvae (4.1–5.5 versus 2.1–2.5). Fecundity of M. confusa was significantly higher than for O. insidious, 10.6 ± 1.5 eggs per 48 h versus 5.0 ± 1.4, respectively. Greenhouse tests on heavily infested F. benjamina revealed that M. confusa was a highly effective predator of G. uzeli. Evaluations with three F. benjamina cultivars showed that M. confusa reproduced throughout the year and reduced thrips populations ⩾95% and leaf galls by up to 77% within 5 weeks. By contrast O. insidiosus did not establish or significantly reduce populations of G. uzeli inside leaf galls. Methods to monitor and protect M. confusa in urban landscapes are discussed. 相似文献
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The morphology of the spermatheca and eggs of Odontotarsus purpureolineatus were studied by optical microscopy and scanning electron microscopy. The spherical eggs were about 1.35 mm long and 1.09
mm wide. The egg batches generally consist of 13–14 eggs. The egg surface is covered by polygonal (hexagonal and pentagonal
shapes prevail) ridges and tiny chorionic tubercles. There were 8–10 aero-micropylar processes between the polygons. The spermatheca
of O. purpureolineatus is characterized by a spherical spermathecal bulb, a pumping region, a flange of pump and dilation of spermathecal duct.
Spermathecal processes and a median spermathecal dilation with sclerotized rod are missing. The spermathecal bulb and the
pumping region possess many pores. 相似文献
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Four flavonoids, including two new compounds, were isolated from the leaf extract of Thymbra spicata. The new compounds were the 7,3′-dimethyl and 7,3′,4′-trimethyl ethers of 6-hydroxyluteolin. All the compounds were identified by spectral methods. 相似文献