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71.
72.
The pituitary is an important endocrine tissue of the vertebrate that produces and secretes many hormones. Accumulating data suggest that several types of cells compose the pituitary, and there is growing interest in elucidating the origin of these cell types and their roles in pituitary organogenesis. Therein, the histogenous cell line is an extremely valuable experimental tool for investigating the function of derived tissue. In this study, we compared gene expression profiles by microarray analysis and real-time PCR for murine pituitary tumor-derived non-hormone-producing cell lines TtT/GF, Tpit/F1 and Tpit/E. Several genes are characteristically expressed in each cell line: Abcg2, Nestin, Prrx1, Prrx2, CD34, Eng, Cspg4 (Ng2), S100β and nNos in TtT/GF; Cxcl12, Raldh1, Msx1 and Twist1 in Tpit/F1; and Cxadr, Sox9, Cdh1, EpCAM and Krt8 in Tpit/E. Ultimately, we came to the following conclusions: TtT/GF cells show the most differentiated state, and may have some properties of the pituitary vascular endothelial cell and/or pericyte. Tpit/F1 cells show the epithelial and mesenchymal phenotypes with stemness still in a transiting state. Tpit/E cells have a phenotype of epithelial cells and are the most immature cells in the progression of differentiation or in the initial endothelial-mesenchymal transition (EMT). Thus, these three cell lines must be useful model cell lines for investigating pituitary stem/progenitor cells as well as organogenesis.  相似文献   
73.
RNA-seq data analysis of cigarette beetle (Lasioderma serricorne) strains having different sensitivities to pyrethroids identified sodium channel mutations in strains showing pyrethroid resistance: the T929I and F1534S mutations. These results suggest that reduced sensitivity of the sodium channel confers the pyrethroid resistance of L. serricorne. Results also showed that the F1534S mutation mostly occurred concurrently with the T929I mutation. The functional relation between both mutations for pyrethroid resistance is discussed.  相似文献   
74.

Background

Application of a multisample method using inulin to estimate glomerular filtration rate (GFR) in cats is cumbersome.

Objectives

To establish a simplified procedure to estimate GFR in cats, a single‐blood‐sample method using inulin was compared with a conventional 3‐sample method.

Animals

Nine cats including 6 clinically healthy cats and 3 cats with spontaneous chronic kidney disease.

Methods

Retrospective study. Inulin was administered as an intravenous bolus at 50 mg/kg to cats, and blood was collected at 60, 90, and 120 minutes later for the 3‐sample method. Serum inulin concentrations were colorimetrically determined by an autoanalyzer method. The GFR in the single‐blood‐sample method was calculated from the dose injected, serum concentration, sampling time, and estimated volume of distribution on the basis of the data of the 3‐sample method.

Results

An excellent correlation was observed (r = 0.99, P = .0001) between GFR values estimated by the single‐blood‐sample and 3‐sample methods.

Conclusions and Clinical Importance

The single‐blood‐sample method using inulin provides a practicable and ethical alternative for estimating glomerular filtration rate in cats.  相似文献   
75.
The 2011 earthquake severely damaged the Fukushima Daiichi Nuclear Power Plant (FNPP), resulting in the release of large quantities of radioactive material into the environment. The deposition of these radionuclides in rice straw as livestock feed led to the circulation of contaminated beef in the market. Based on the safety concern of the consumers, a reliable method for estimating concentrations of radioactive cesium in muscle tissue is needed. In this study, we analyzed the concentrations of radioactive cesium in the blood and skeletal muscle of 88 cattle, and detected a linear correlation between them. We then developed software that can be used to estimate radioactive cesium concentrations in muscle tissue from blood samples. Distribution of this software to the livestock production field would allow us to easily identify high‐risk cattle, which would be beyond the safety regulation, before shipping out to the market. This software is planned to be released as freeware. This software would contribute to food safety, and aid the recovery of the livestock industry from the damage creacted by the 2011 Tohoku earthquake and tsunami.  相似文献   
76.
Recently, the analysis of the microbial community structure in soil has received a great deal of attention. Various analytical methods based on biomarkers have been developed: 16S-rDNA, total DNA, phospholipid fatty acids, ergosterols, muramic acids, etc. (Tunlid and White 1992; Carter and Lynch 1993). In a previous paper, we reported that respiratory quinones are useful biomarkers to characterize the microbial community structure in soil (Fujie et al. 1998). In these analyses, only fresh moist soils or frozen soils had been used as samples. However, the soil samples are generally stored in the dark after air drying in many research institutes and experimental stations. It was considered that the analysis of microbial communities in dried soil samples was not possible.

In this paper, we observed that the drying of soils did not affect the proportions of quinone species in soil although the treatment decreased the amount of extracted quinones. These findings suggest that the analysis of the respiratory quinone profile of dried soils reflects the micro biota present in fresh moist soils before drying.  相似文献   
77.
Improved varieties of pigeonpea (Cajanus cajan L. Millsp.) still retain some growth characteristics of perennial types of wild species such as slow seedling growth and rato on ability which are considered to be major yield-restricting characteristics when the growth period is shortened. Studies on the physiological background of slow initial growth may help improve the potential productivity of short-duration pigeonpea. It was found that the low seedling vigor of pigeonpea could be ascribed to the small seed size (Narayanan et al. 1981; Brakke and Gardner 1987), low rate of photosynthetic CO2 fixation (Rawson and Constable 1981), and low rates of metabolic processes (Huber and Hanson 1992; Ito et al. 1996). However, few authors have related the slow growth to the retention of current photosynthates and leaf respiration during the night. In contrast, seedling growth of cowpea (Vigna sinensis Endl.) was reported to be vigorous (Brakke and Gardner 1987).

The objectives of this study were to characterize the initial growth of pigeonpea in comparison with cowpea. Two experiments were carried out, one dealing with growth analysis and the other with O2 uptake of leaf and retention of current photosynthates during the night.  相似文献   
78.
Quinone profile analysis of stored air-dried soils gave an approximation of the long-term changes in the microbial community structure in four soils subjected to different types of fertilizer application from 1987 to 1997: unfertilized soil (NF-soil), soil amended with chemical fertilizers (CF-soil), soil amended with chemical fertilizers and 40 t ha-1 y-1 of farmyard manure (CF+ FYM-soil), and soil amended with 400 t ha-1 y-1 of farmyard manure (FYM-soil). The carbon content increased, and the soil pH remained higher in the soils receiving farmyard manure. Principal component analysis of the quinone profiles of the soils indicated that the microbial community structure showed a high similarity among the four soils before the onset of cultivation and changed to a different community structure specific to the respective fertilizing practices except for the NF-soil. The specific quinone profile became stable after two cropping seasons in the FYM-soil, after 10 cropping seasons in the CF+ FYM-soil and after 15 cropping seasons in the CF-soil, respectively. The quinone profile of the NF-soil did not become stable, and no specific profile was developed. The specific quinone profiles in the FYM- and CF+ FYM-soils were both characterized by large mole fractions of menaquinone with seven isoprenoid units (MK-7). Farmyard manure itself contained a large mole fraction of MK-7. It was suggested that the amount of MK-7 increased due to the application of farmyard manure. MK-7 indicates the presence of Gram-positive bacteria with low guanine plus cytosine contents such as Bacillus and Gram-negative bacteria of the Cytophaga-Flavobacterium complex. The specific quinone profile in the CF-soil was characterized by the presence of menaquinone with seven isoprenoid units dihydrated (MK-7(H2)and MK-7(H4). Although Brevibacterium and Kocuria contain MK-7(H2), no microorganisms are known to have MK- 7(H.) as major quinone. The common major quinones were MK-8, MK-10(H4) and a mixture of MK-8(H4) and MK-9, suggesting the predominance of Grampositive bacteria in all the soils. Mole fractions of Ubiquinone with 8 isoprenoid units (Q-8) and Q-10 increased at various times in all the soils, indicating the sporadic growth of Gram-negative bacteria.  相似文献   
79.
A new extraction method for the evaluation of Si availability in slag fertilizers was developed based on findings on the dissolution process of the slags in paddy fields. In the method, the slags were dissolved in water with the addition of a weakly acidic cation exchange resin (H form). The effects of the slag/water ratio, the amount of resin, and temperature on the Si dissolution from the slags were examined in order to determine adequate extraction conditions. The Si dissolution from the slags was enhanced by the addition of the resin. The pH of the extractant was well controlled between 6 and 7 during the extraction. The percentage of the amount of Si extracted by traditional evaluation methods using 0.5 м HCl or an acetate buffer solution to the total amount of Si in the slags was much higher than the Si recovery rate by rice plant (Oryza sativa L. var. Nihonbare) which was measured in our previous study. Moreover, there was no correlation between these values. On the other hand, the percentage of Si extracted by the new method was in the same range as that of the Si recovery rate and a positive correlation was obtained. As a result, Si availability in the slags could be evaluated more precisely by using the method proposed here than by using the traditional methods.  相似文献   
80.
Tobacco (Nicotiana tabacum L.) leaf starch is degraded to sugars through curing (42°C/82.3% relative humidity/72 h). Total carbohydrate content remained almost constant, starch content decreased markedly, and soluble sugar content (mostly glucose) increased. α-Amylase and starch phosphorylase activities increased sixfold and threefold, respectively, whereas β-amylase activity was unaltered and isoamylase activity decreased. Increased α-amylase activity was accompanied by increased α-amylase protein levels. Although tobacco has four α-amylase gene members, only NtAMY1 mRNA levels increased. For other starch degradation genes, such as NtBAM1 and NtBMY2 (β-amylase), NtISO1 and NtISO2 (isoamylase) and NtGWD1 and NtGWD3 (glucan water dikinase), the mRNA levels remained unaltered during the first 48 h of curing. NtAMY1 expression was induced by osmotic stress but was unaffected by high temperature and/or injury stresses. Similarly, soluble sugar contents were largely increased by osmotic stress. This suggests that starch is degraded by α-amylase during curing and that α-amylase is coded by NtAMY1, induced by osmotic stress.  相似文献   
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