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81.
Kazuki Miyaji Maki Kato Nobuyo Ohtani Mitsuaki Ohta 《Journal of applied animal welfare science : JAAWS》2013,16(4):355-362
The objective of this study was to evaluate the effects of diet on the feline stress response by measuring plasma and urinary cortisol. A study diet was developed with a unique combination of nutrients that supports the management of stressful situations. The specific formulation of the diet included alpha-casozepine, which is believed to have an anxiolytic effect, and tryptophan supplementation. Tryptophan is the precursor for the synthesis of the neurotransmitter serotonin. Twenty-one indoor cats were fed with the study diet (n = 10) or a control diet (n = 11) for 8 weeks, after which physiological responses were evaluated. The study diet significantly increased the ratio of plasma tryptophan to large neutral amino acids and decreased urinary cortisol concentrations after being consumed daily for 8 weeks, but there was no effect on plasma cortisol levels following a stressful event (veterinary examination and blood draw). Further studies, such as behavioral analyses, are needed to clarify the effects of the study diet. 相似文献
82.
Hiroyuki Kajiura Masashi Wasai Saori Kasahara Fumio Takaiwa Kazuhito Fujiyama 《Molecular biotechnology》2013,54(3):784-794
Cholera toxin B subunit (CTB) is widely used as a carrier molecule and mucosal adjuvant and for the expression of fusion proteins of interest. CTB-fusion proteins are also expressed in plants, but the N-glycan structures of CTB have not been clarified. To gain insights into the N-glycosylation and N-glycans of CTB expressed in plants, we expressed CTB in rice seeds with an N-terminal glutelin signal and a C-terminal KDEL sequence and analyzed its N-glycosylation and N-glycan structures. CTB was successfully expressed in rice seeds in two forms: a form with N-glycosylation at Asn32 that included both plant-specific N-glycans and small oligomannosidic N-glycans and a non-N-glycosylated form. N-Glycan analysis of CTB showed that approximately 50 % of the N-glycans had plant-specific M3FX structures and that almost none of the N-glycans was of high-mannose-type N-glycan even though the CTB expressed in rice seeds contains a C-terminal KDEL sequence. These results suggest that the CTB expressed in rice was N-glycosylated through the endoplasmic reticulum (ER) and Golgi N-glycosylation machinery without the ER retrieval. 相似文献
83.
Maki Sugaya Futoshi Nishimura Akira Katoh Kazuo Harada 《Nucleosides, nucleotides & nucleic acids》2013,32(5):534-545
In this study, the ability to tailor the peptide-binding specificity of an RNA was investigated. First, variants of the Rev-response element (RRE) RNA with different specificities toward the natural binding partner, Rev, and two RRE-binding aptamers, the RSG-1.2 and the Kl peptides, were identified. Next, hybrid RRE mutants with combinations of two sets of specificity-altering substitutions were tested for peptide-binding specificity. It was shown that in most cases the results of the combination of individual mutations were of an additive nature, therefore providing a way to manipulate the peptide-binding specificity of an RNA in a predictable manner. 相似文献
84.
Atsuko Miyagi Maki Kawai-Yamada Minori Uchimiya Noriyuki Ojima Koichi Suzuki Hirofumi Uchimiya 《Metabolomics : Official journal of the Metabolomic Society》2013,9(6):1254-1261
Evolution has shown the co-dependency between host plants and predators (insects), especially inevitable dependency of predators on plant biomass for securing their energy sources. It was postulated that NAD+ source used for major energy producing pathway is the glycerol-3-phosphate shuttle in insects. Using high throughput metabolomics approach, we found that larva of leaf beetle (Gastrophysa atrocyanea), which feed oxalate-rich plants (Rumex obtusifolius), possessed a unique mechanism for accumulating unusually high amounts of lactate. Similarly, larva of butterfly (Papilio machaon) fed with fennel (Foeniculum vulgare) accumulated lactate. Same butterfly also showed the elevated level of glycerol-3-phosphate equivalent to lactate. These evidences provide new insights into the mechanism underlying metabolite alteration between host plants and insect herbivores. 相似文献
85.
Background
Vitamin D is an important micronutrient for health. Hypovitaminosis D is thought to play a role in the seasonality of a number of diseases and adverse health conditions. To refine hypotheses about the links between vitamin D and seasonal diseases, good estimates of the cyclicality of serum vitamin D are necessary.Objectives
The objective of this study is to describe quantitatively the cyclicality of 25-hydroxyvitamin D (25OHD) in the United States. We provide a statistical analysis with weekly time resolution, in comparison to the quarterly (winter/spring/summer/fall) estimates already in the literature.Methods
We analyzed time series data on 25OHD, spanning 287 consecutive weeks. The pooled data set comes from 3.44 million serum samples from the United States. We statistically analyzed the proportion of sera that were vitamin D sufficient, defined as 25OHD ng/mL, as a function of date.Results
In the United States, serum 25OHD follows a lagged pattern relative to the astronomical seasons, peaking in late summer (August) and troughing in late winter (February). Airmass, which is a function of solar altitude, fits the 25OHD data very well when lagged by 8 weeks.Conclusions
Serum vitamin D levels can be modeled as a function of date, working through a double-log transformation of minimal solar airmass (easily calculated from solar altitude, retrievable from an online solar altitude/azimuth table). 相似文献86.
87.
Daisuke Takagi Atsuko Miyagi Youshi Tazoe Mao Suganami Maki Kawai-Yamada Akihiro Ueda Yuji Suzuki Ko Noguchi Naoki Hirotsu Amane Makino 《Plant, cell & environment》2020,43(9):2033-2053
Phosphorus (P) is an essential mineral nutrient for plants. Nevertheless, excessive P accumulation in leaf mesophyll cells causes necrotic symptoms in land plants; this phenomenon is termed P toxicity. However, the detailed mechanisms underlying P toxicity in plants have not yet been elucidated. This study aimed to investigate the molecular mechanism of P toxicity in rice. We found that under excessive inorganic P (Pi) application, Rubisco activation decreased and photosynthesis was inhibited, leading to lipid peroxidation. Although the defence systems against reactive oxygen species accumulation were activated under excessive Pi application conditions, the Cu/Zn-type superoxide dismutase activities were inhibited. A metabolic analysis revealed that excessive Pi application led to an increase in the cytosolic sugar phosphate concentration and the activation of phytic acid synthesis. These conditions induced mRNA expression of genes that are activated under metal-deficient conditions, although metals did accumulate. These results suggest that P toxicity is triggered by the attenuation of both photosynthesis and metal availability within cells mediated by phytic acid accumulation. Here, we discuss the whole phenomenon of P toxicity, beginning from the accumulation of Pi within cells to death in land plants. 相似文献
88.
Kano Rui Kimura Utako Kakurai Maki Hiruma Junichiro Kamata Hiroshi Suga Yasushi Harada Kazutoshi 《Mycopathologia》2020,185(6):947-958
Mycopathologia - In this report, we describe the first isolation of two highly terbinafine (TRF)-resistant Trichophyton interdigitale-like strains from a Nepali patient and an Indian patient with... 相似文献
89.
Abdelmadjid Djoumad Audrey Nisole Don Stewart Dave Holden Reza Zahiri Maki N. Inoue Viatcheslav V. Martemyanov Roger C. Levesque Richard C. Hamelin Michel Cusson 《Systematic Entomology》2020,45(2):493-504
For regulatory purposes, the name ‘Asian gypsy moth’ refers to a group of closely related Asian Lymantria species and subspecies whose female moths display flight capability, a trait believed to confer enhanced invasiveness relative to the European gypsy moth, Lymantria dispar dispar, whose females are flightless. Lymantria albescens and Lymantria postalba are Asian gypsy moths occurring in the southern Ryukyu Islands and in the northern Ryukyu and adjacent Kyushu and Shikoku Islands of Japan, respectively. Although once considered subspecies of L. dispar, their status as distinct species, relative to the latter, is now well established. While postalba was subsequently considered a subspecies of L. albescens, largely on the basis of differences in forewing ground colour in males, both taxa were later given distinct species status by Pogue & Schaefer (2007) following their revision of the genus Lymantria. Here, we re-examined the validity of this revised status through the sequencing of a large portion of the mitochondrial genome (c. 60%) and multiple nuclear marker genes [elongation factor 1-alpha (Ef-1α), wingless (Wgl), internal transcribed spacer 2 (ITS-2), ribosomal protein S5 (RpS5)] in representative specimens of both taxa and other Lymantria species, including L. monacha, L. xylina, L. mathura and members of the L. dispar + L. umbrosa clade. A comparison of the number of substitutions in these genomic regions among the taxa we considered showed lower or equivalent variation between L. albescens and L. postalba compared with subspecies of L. dispar, for mitochondrial and nuclear sequences, respectively. This finding was reflected in the maximum likelihood trees generated independently for mitochondrial and nuclear data, where L. albescens and L. postalba formed, in both analyses, a short-branch sister clade basal to the L. dispar + L. umbrosa clade. We further sequenced three markers [cytochrome c oxydase 1 (COI), EF-1α, Wgl] in multiple L. albescens–L. postalba specimens collected along a south-to-north transect across the Ryukyu Arc and observed no clear distinction among the sampled specimens as a function of taxonomic designation. We conclude that L. albescens and L. postalba form a single species, with postalba representing a darker-winged morph along an apparent south-to-north wing colour cline. Accordingly, L. postalba is relegated to synonymy under L. albescens ( syn.n. ). 相似文献