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101.
Somatic cell nuclear transfer (SCNT) has been exploited in efforts to clone and propagate valuable animal lineages. However, in many instances, recipient oocytes are obtained from sources independent of donor cell populations. As such, influences of potential nuclear-cytoplasmic incompatibility, post SCNT, are largely unknown. In the present study, alterations in mitochondrial protein levels were investigated in adult SCNT pigs produced by microinjection of Meishan pig fetus fibroblast cells into enucleated matured oocytes (maternal Landrace genetic background). Mitochondrial fractions were prepared from liver samples by mechanical homogenization and differential centrifugation. Liver mitochondria were then subjected to two-dimensional difference gel electrophoresis (2-D DIGE). Protein expression changes were confirmed with a volume ratio greater than 2 fold (P<0.05). 2-D DIGE analysis further revealed differential expression of three proteins between the Meishan (n=3) and Landrace (n=3) breeds. Differential expression patterns of 16 proteins were detected in SCNT pig liver tissue (n=3) when compared with Meishan control samples. However, none of the 16 proteins correlated with the three differentially expressed Meishan and Landrace liver mitochondrial proteins. In summary, alteration of mitochondrial protein expression levels was observed in adult SCNT pigs that did not reflect the breed difference of the recipient oocytes. Comparative proteomic analysis represents an important tool for further studies on SCNT animals.  相似文献   
102.
The db/db mouse is one of the diabetes mellitus animal models and if the pathophysiological stages of diabetic changes in the mouse model could simulate the stages in human diabetes, the db/db mouse could be used to better evaluate drug candidates. Blood insulin, HbA1c levels and morphological features of pancreatic islets in db/db mice were evaluated to determine the pathophysiological stage. At 6 weeks of age, db/db mice showed the highest level of plasma insulin and lowest level of HbA1c, and histopathological examination revealed enlarged islets with a circular shape and hypertrophic islet cells. By 9 and 12 weeks of age, the plasma insulin levels had decreased to mid levels and HbA1c had increased to mid to high levels; histopathological examination at this time revealed two types of islets coexisting, enlarged circular islets and small irregular-shaped islets. By 15 and 22 weeks of age, plasma insulin had decreased further to low levels and HbA1c was at its highest level; the histopathological examination at this time revealed an increase in irregular-shaped and small islets. Based on blood insulin levels, HbA1c levels and histopathology findings in the db/db mice in this study, the clinical staging of diabetic changes were recognized. The pathophysiological stages of diabetes mellitus in this animal model were similar to the stages in humans.  相似文献   
103.
Increase in the blood supply to individual follicles appears to be associated with follicular growth rates and the ability to become the dominant follicle, while reduced thecal vascularity appears to be closely associated with follicular atresia. Therefore, this study aimed to determine the real-time changes in the vascularity of the follicle wall during the first follicular wave in cycling Holstein cows. Normally cycling and lactating cows (n=5) were examined by transrectal color Doppler ultrasonography (the sensitivity for velocity: > 2 mm/sec) to determine the changes in the vasculature of the follicle wall (presence or absence of blood flow) and the diameter of follicles. A new follicular wave and ovulation were induced by GnRH injection at 48 h after an injection of PGF2alpha analogue. The ovaries were scanned daily for 7 days after GnRH injection. Follicles >2.5 mm were classified into 3 groups by the changes in diameter as follows: 1) largest follicle, 2) second largest follicle, and 3) small follicles, which included all other follicles >2.5 mm. Before the follicle selection, there was no significant difference in the percentage of follicles with detectable blood flow between the subsequently determined largest and second largest follicles. After the follicle selection, the percentage of follicles with detectable blood flow significantly decreased among the second largest follicles. In addition, small follicles with detectable blood flow kept larger diameters than those without detectable blood flow from one day before the occurrence of follicle selection. It is likely that maintenance of follicle vasculature and appropriate blood supply to the larger follicles is essential for follicle dominance. In small follicles, the presence of blood flow within the wall also appears to be required for recruitment. Consequently, the data suggest that the change of the blood supply to an individual follicle closely relates to the dynamics of follicular growth in the first follicular wave in the cow.  相似文献   
104.
The clustered hrp genes encoding the type III secretion system in the Japanese strains MAFF301237 and MAFF311018 of Xanthomonas oryzae pv. oryzae were sequenced and compared. The strains differ in their pathogenicity, location, and year of isolation. A 30-kbp sequence comprising 29 open reading frames (ORFs) was identical in its structural arrangement in both strains but differed from X. campestris pv. campestris, X. axonopodis pv. citri, and X. axonopodis pv. glycines in certain genes located between the hpaB-hrpF interspace region. The DNA sequence and the putative amino acid sequence in each ORF was also identical in both X. oryzae pv. oryzae strains as were the PIP boxes and the relative sequences. These facts clearly showed that the structure of the hrp gene cluster in X. oryzae pv. oryzae is unique.  相似文献   
105.
OBJECTIVE: To evaluate changes in heart rate (HR) and mean arterial pressure (MAP) as indicators of changes in pressor response for muscle afferents after topical application of menthol (MEN)-based analgesic balm. ANIMALS: 11 decerebrate cats. PROCEDURE: Pressor responses were reflexively evoked by static contraction of hind limb muscles, which are caused by group III and IV afferents. Responses were monitored without interference from anesthesia or effects of higher brain function by the use of decerebrate cats. After obtaining baseline data, MEN analgesic balm (1.9%) was applied to the skin over contracting muscles of 1 hind limb in 6 cats; petrolatum was applied to 5 control cats. Muscle contractions were evoked every 10 minutes, alternating between hind limbs, for 120 minutes. Peak MAP and HR were analyzed. RESULTS: Peak MAP responses evoked by static muscle contraction for the ipsilateral hind limb were significantly attenuated 20 minutes after application, but approached baseline values 40 minutes after application. The pressor response was significantly decreased 20 minutes after application during the last 12 seconds of the stimulus, which was attributed to group IV afferents. There were no significant differences in HR responses. CONCLUSIONS AND CLINICAL RELEVANCE: Application of MEN analgesic balm to the skin over contracting muscles significantly decreased the pressor response to static muscle contractions. This suggests that topical application of MEN has effects on responses evoked from receptors located in muscles. The MEN analgesic balm appeared to attenuate the pressor response 20 minutes after application, but it was a short-term effect.  相似文献   
106.
1. Histological and histochemical profiles of Musculus pectoralis (PT, type IIB fibres), M. iliotibialis lateralis (ITL, types IIA + IIB fibres) and M. puboischiofemoralis pars medialis (PIF, type I fibres) were compared in carbon dioxide (37%, 70 s) and electrically (14 V, 5 s) stunned male chickens. 2. Muscle materials were taken at 0, 4 and 24 h from carcases dressed and cooled with ice-water mixture for 30 min. Glycogen and fat contents, and adenosine triphosphatase and reduced nicotinamide adenine dinucleotide dehydrogenase activities of fibres were measured. 3. In PT muscle at 0 h, gas stunned chickens showed many fibres with high glycogen content but those electrically stunned contained few such fibres. Fibres from gas stunned birds had lost almost all their glycogen after 24 h of cold storage. 4. In the ITL muscle of gas stunned chickens at 0 h residual glycogen was observed in type IIB fibres. In contrast, in the electrically stunned birds it was in type IIA, showing the different effects of the stunning methods. During cold storage, glycogen disappeared earlier in type IIB than IIA fibres. 5. In PIF muscle with fibres of low glycogen content, the gas stunned chickens maintained a good fibre structure for 4 h or more, but the electrically stunned had already lost intact fibre structure at 4 h. 6. These results indicated that the carbon dioxide stunning was a better method for chicken welfare and meat quality than electrical stunning.  相似文献   
107.
Microdialysis System (MDS) is a novel technique used for investigation of molecule secretion between different cell populations. Local hormonal secretion at follicular wall has been still unclear. This MDS study was used to determine progesterone (P4), androstenedione (A4), estradiol-17beta (E2) and Prostaglandin F2alpha (PGF2alpha) release in mare pre-ovulatory follicles. Follicles larger than 30 mm were isolated from the ovary and follicular fluid aspirated for hormone assay. Follicular fluid collected from small, middle and large follicles were analyzed by EIA. The concentrations of P4 and PGF2alpha were similar among the different sizes of follicles. The release of A4 was observed in middle and large follicles. E2 concentration was observed in middle follicles and was higher in large follicles compared with middle follicles. Follicular wall was cut and incubated for MDS and when LH was infused, there was an increase in P4 and A4 release. PGF2alpha release was considerably high after LH infusion compared to the control group. Infusion of PGF2alpha increased P4 and A4 release but there was no change in E2 release. This results suggest that in pre-ovulatory follicles, LH stimulates theca interna cells and also PGF2alpha seemed to have a mediator role to induce steroid hormone production and luteinization of follicular cells. The nature of the mechanisms involved in selection of large follicles is still a perplexing research problem in reproduction.  相似文献   
108.
109.
An innovative technique for green tea's quality determination was developed by means of metabolomics. Gas-chromatography coupled with time-of-flight mass spectrometry and multivariate data analysis was employed to evaluate the quality of green tea. Alteration of green tea varieties and manufacturing processes effects a variation in green tea metabolites, which leads to a classification of the green tea's grade. Therefore, metabolic fingerprinting of green tea samples of different qualities was studied. A set of ranked green tea samples from a Japanese commercial tea contest was analyzed with the aim of creating a reliable quality-prediction model. Several multivariate algorithms were performed. Among those, the partial least-squares projections to latent structures (PLS) analysis with the spectral filtering technique, orthogonal signal correction (OCS), was found to be the most practical approach. In addition, metabolites that play an important role in green tea's grade classification were identified.  相似文献   
110.
Sieve tubes have been attracting widespread research interest because of their possible role in mediating physiological signals within the whole plant. However, progress in research into the function of sieve tubes has been limited by the low volume of sap available. To overcome this problem, we attempted to collect phloem exudate from tropical coconut palm trees (Cocos nucifera L. cv. Namhom). As much as 3 to 15 mL of exudate per hour was collected from the cut surface of the plant's fruit-bearing stem. Our analyses revealed that the characterized profiles of sugars (sucrose: 339 mM), amino acids (total concentration: 17.1 mM), cations (potassium: 48.3 mM), and proteins (total concentration: 0.1 /-lg /-lL-1) in the exudate were mostly consistent with those of phloem sap or phloem exudate collected from rice plants, castor bean plants, etc. This exudate was assumed to reflect the composition of the phloem sap from the source organs of coconut palm trees. The large volume of exudate collected contributed significantly to the analyses of the various compounds in the stream of sieve tubes.  相似文献   
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