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11.
The objective of this study was to investigate the effects of ribose supplementation on blood ammonia-N, plasma lactic acid, plasma glucose, volume of oxygen consumption (VO2), heart rate, and performance in Thoroughbred geldings performing a maximal treadmill standardized exercise test (SET). The hypothesis tested was that ribose supplementation would decrease ammonia-N and lactic acid accumulation during exercise, and improve performance. Eight Thoroughbred geldings were assigned randomly to one of two groups: glucose or ribose. The glucose group received 0.15 g glucose/kg of BW, and the ribose group received 0.15 g of ribose/kg BW top-dressed on the feed twice daily. After 2 wk of glucose or ribose supplementation, a SET was performed. Blood was analyzed for blood ammonia-N, plasma lactic acid, and plasma glucose before exercise (0 min), every minute during SET, and at 15 and 30 min after exercise. Heart rate and VO2 were recorded for the duration of SET. After a 10-d washout period, geldings switched groups. Following another 2 wk of supplementation, a second SET was performed, and same data recorded. Blood ammonia-N and plasma lactic acid increased as duration of SET increased and reached a peak at 15 min after exercise. Peak plasma glucose was observed at 15 min after exercise, and peak heart rate and VO2 were recorded at highest speed during SET. Geldings supplemented with ribose had blood ammonia-N, plasma lactic acid, plasma glucose, VO2, heart rate, and performance similar to those of geldings supplemented with glucose. Results from this study show that supplementation with 0.15 g ribose/kg BW twice daily in the diet of conditioned Thoroughbred geldings for 2 wk does not influence blood ammonia-N, plasma lactic acid, plasma glucose, VO2, heart rate, or performance during SET or the first 30 min of recovery.  相似文献   
12.
Chicken interleukin-17 (chIL-17) gene was previously characterized through cloning from a chicken intestinal expressed sequence tag (EST) cDNA library. To further investigate the biological properties of chIL-17, six monoclonal antibodies (mAbs) against a bacterially expressed chIL-17 recombinant protein were produced and their binding specificities characterized. Antibodies which were initially selected on the basis of their specific binding reactivity with recombinant chIL-17 in ELISA were further characterized by Western blot analysis. Monoclonal antibodies specific for chIL-17 identified 20 and 21kDa protein bands in the culture supernatant and cell lysate of CU205 cells. These mAbs also recognized specific bands for chIL-17 in the cell lysate from conconavalin A (Con A)-activated, but not from normal splenic lymphocytes. Furthermore, these mAbs detected a 16kDa protein in the lysate of CU205 cells treated with tunicamycin and stained an intracellular protein in CU205 cells in flow cytometric analysis. Together, these results indicate that these new mAbs are specific for chIL-17 and will be a useful tool for structural and immunological studies of IL-17 in poultry.  相似文献   
13.
This study evaluated the pregnancy rates following either a controlled internal drug release (CIDR)-based timed artificial insemination (TAI) or an embryo transfer (TET) protocol compared with that following a single PGF(2alpha) injection and AI after estrus (AIE) in lactating repeat breeder dairy cows. Fifty-three lactating dairy cows diagnosed as repeat breeders were used in this study and were randomly assigned to the following three treatments. (1) Cows, at random stages of the estrous cycle, received a CIDR device and 2 mg estradiol benzoate (EB; Day 0), a 25 mg PGF(2) (alpha) injection at the time of CIDR removal on Day 7 and a 1 mg EB injection on Day 8. The cows then received TAI 30 h (Day 9) after the second EB injection using dairy semen (TAI group, n=13). (2) Cows, at random stages of the estrous cycle, received the same hormonal treatments as in the TAI group. The cows then received TET on Day 16 using frozen-thawed blastocysts or morula embryos collected from Korean native cattle donors (TET group, n=13). (3) Cows, at the luteal phase, received a 25 mg injection of PGF(2alpha) and AIE using dairy semen (control group, n=27). The ovaries of the cows in the TET group were examined by transrectal ultrasonography to determine ovulation of the preovulatory follicles, and blood samples were collected for serum progesterone (P4) analysis. The pregnancy rate was significantly higher in the TET group (53.8%) than in the control (18.5%) or TAI (7.7%) groups (P<0.05). The ultrasonographic observations demonstrated that all the cows in the TET group ovulated the preovulatory follicles and concomitantly formed new corpora lutea. Accordingly, the mean serum P4 concentration remained constant between Day 0 and Day 7 of the luteal phase, decreased dramatically on Day 8 (P<0.01) and subsequently increased by Day 16 (P<0.01). These data suggest that the CIDR-based TET protocol can be used to effectively increase the pregnancy rate in lactating repeat breeder dairy cows.  相似文献   
14.
The objective of this study was to investigate the effect of dosage and number of days of follicle stimulating hormone (FSH) treatment on superovulatory response in controlled internal drug release (CIDR)-treated Korean native cows. Forty cows underwent two superovulatory treatments with a crossover design. Cows, at random stages of the estrous cycle, received a CIDR together with injections of 1 mg estradiol benzoate and 50 mg progesterone, and gonadotropin treatment began 4 days later. The cows were divided into 2 groups based on the dosage and number of days of treatment with porcine FSH; a total of 28 mg FSH was given in twice daily intramascular injections in decreasing doses over 4 days (5, 5, 4, 4, 3, 3, 2 and 2 mg; T1 group, n=20) or a total of 24 mg FSH was given in twice daily decreasing doses over 3 days (5, 5, 4, 4, 3 and 3 mg; T2 group, n=20). This was followed by the alternate treatment in the subsequent superovulation. The cows were treated identically in all other respects. PGF(2alpha) (25 mg and 15 mg) was given with the 5th and 6th injections of FSH, CIDR were withdrawn at the 6th FSH injection and the cows received 200 microg GnRH 36 h after CIDR withdrawal. The cows were artificially inseminated twice, at 48 and 60 h after CIDR withdrawal, using commercial semen from four Korean native bulls, and embryos were recovered 6 or 7 days after the 2nd insemination. The numbers of corpora lutea (CL; 7.9+/-1.0 vs. 8.3+/-1.1) and large follicles (1.2+/-0.2 vs. 1.3+/-0.3) present at the time embryo recovery, as detected by ultrasonography, did not differ between the T1 and T2 groups (P>0.05). Similarly, the numbers of total ova/embryos (6.2+/-0.9 vs. 6.4+/-1.1), transferable embryos (3.4+/-0.8 vs. 3.2+/-0.7), degenerate embryos (0.8+/-0.2 vs. 1.0+/-0.3) and unfertilized ova (2.1+/-0.5 vs. 2.2+/-0.5) did not differ between the groups (P>0.05). These data indicate that a reduced dose (24 vs. 28 mg) and number of treatments (6 vs. 8) of FSH for superovulation of CIDR-treated Korean native cows does not affect the embryo yield.  相似文献   
15.
The actin-binding protein gelsolin is involved in remodeling the actin cytoskeleton during growth-factor signaling, apoptosis, cytokinesis, and cell movement. Calcium-activated gelsolin severs and caps actin filaments. The 3.4 angstrom x-ray structure of the carboxyl-terminal half of gelsolin (G4-G6) in complex with actin reveals the basis for gelsolin activation. Calcium binding induces a conformational rearrangement in which domain G6 is flipped over and translated by about 40 angstroms relative to G4 and G5. The structural reorganization tears apart the continuous beta sheet core of G4 and G6. This exposes the actin-binding site on G4, enabling severing and capping of actin filaments to proceed.  相似文献   
16.
To assess and describe the use of rabies post‐exposure prophylaxis (PEP) related to mass bat exposures (MBEs) in the literature and in the state of Rhode Island. Data on MBE events occurring between 2010 and 2016 from the Rhode Island Department of Health (RIDOH) were reviewed to determine PEP usage. For comparison, a systematic review was also performed by searching PubMed, EMBASE, Cochrane Library and Web of Science using the keywords ‘rabies,’ ‘bat’ and ‘exposure.’ There were three MBE events in Rhode Island between 2010 and 2016 in which groups of individuals were asleep during the potential exposure. As a result, RIDOH provided PEP to those involved in the event. In a systematic review of 12 published reports, a variety of settings were involved in MBEs: camping sites, a domestic flight, a neonatal intensive care unit and dormitories. The number of potential rabies exposures ranged from five to 1,429 people. PEP recommendations for assessed persons ranged from 0% to 100% across events (median 21%). The variation in PEP recommendations following a MBE may be dependent on medical need, past precedent or preference. Federal guidance for MBE is needed to add clarity and to minimize the variability in PEP recommendations for such events in the future.  相似文献   
17.
Although structure determination of soluble proteins has become routine, our understanding of membrane proteins has been limited by experimental bottlenecks in obtaining both sufficient yields of protein and ordered crystals. Mistic is an unusual Bacillus subtilis integral membrane protein that folds autonomously into the membrane, bypassing the cellular translocon machinery. Using paramagnetic probes, we determined by nuclear magnetic resonance (NMR) spectroscopy that the protein forms a helical bundle with a surprisingly polar lipid-facing surface. Additional experiments suggest that Mistic can be used for high-level production of other membrane proteins in their native conformations, including many eukaryotic proteins that have previously been intractable to bacterial expression.  相似文献   
18.

Mulberry (Morus spp.) is a cross-pollinating and highly hybridized plant of which productivity are greatly varied in different varieties. Accurate distinction among mulberry varieties and understanding of phylogenetic relationship among them would be crucial for the development of sericulture. We have analysed molecular distinction among four mulberry species and varieties cultivated in DPR Korea by using nuclear ribosomal internal transcribed spacer (ITS) sequences and inter simple sequence repeat (ISSR) markers. ITS sequences doesn’t represent a remarkable interspecific distinction among four mulberry species used in our study, suggesting that it could not be employed to identify them. ISSR analysis using 16 random primers generated 158 different markers ranging from 100 to 4000 bp in size. The results showed the inter-specific genetic variation (55.34%) was slightly higher than intra-specific genetic variation (44.66%), with comparatively low average number of migrants per generation (Nm) among populations (0.3886). Using ISSR primers selected in this study, in the future, the suitable breeding strategy might be established in raising of elite mulberry varieties on the basis of interspecific hybridization.

  相似文献   
19.
The aim of this study was to compare the growth, carcass, histochemical, and meat quality characteristics in Large White pig groups that were categorized by live weight (Heavy and Light) and type I fiber percentage (High and Low), a procedure which resulted in four groups (Heavy-High, Heavy-Low, Light-High, and Light-Low). As expected, the Heavy group showed heavier live weight (114 vs. 94.7 kg, P<0.001) and larger loin eye area (53.3 vs. 47.8 cm2, P<0.001), as well as, higher total number (1,223,000 vs. 1,140,000, P<0.05) and greater mean value cross-sectional area (CSA; 4031 vs. 3798 μm2P<0.05) of muscle fibers than the Light group. However, there were no significant differences in start and finish days among the groups (P>0.05). Heavier pigs harboring a higher percentage of type I fibers (HH) exhibited a similar mean CSA (3894 vs. 4101 μm2) and total number (1,249,000 vs. 1,198,000) of muscle fibers, even though these pigs had a greater CSA of type I fibers (3181 vs. 2719 μm2, P<0.05) and a smaller CSA of type IIB fibers (4048 vs. 4457 μm2, P<0.05) compared to heavier pigs harboring a lower percentage of fiber type I (HL). Both the HL and Light-Low groups exhibited a rapid decline of muscle pH at the early postmortem period (5.90 and 5.85 vs. 6.08, P<0.05), paler surfaces (43.07 and 43.55 vs. 40.73,P<0.05), and higher degrees of fluid loss by exudation (6.26 and 6.39 vs. 4.22%, P<0.05) compared to the HH group due to their muscle fiber type composition. Thus, the HH pigs showed better meat quality characteristics without significant differences in growth and carcass performance compared to the HL pigs. Therefore, selection for increased live weight at the same age and muscle fiber characteristics, especially the increased type I fiber CSA and proportion, is one of the relevant indicators to improve and control meat quality without reducing the growth and carcass performance.  相似文献   
20.
The objective of this study was to investigate muscle fiber growth‐related attributes, especially fiber hyperplasia and hypertrophy, and their relation to growth characteristics in olive flounder. After a conditioning period, juvenile olive flounder (214 g of initial body weight) were weighed after 0, 4, 8, 12, and 24 weeks of a feeding trial and were selected based on mean body weight at each period (G1, G2, G3, G4, and G5, respectively). During the 3.0‐fold increase in body weight (363.1–1,071 g, p < 0.001), the fiber area was increased approximately 2.2 times (p < 0.05), and the median area increased from the G1 to G5 groups (p < 0.05). The G3 group exhibited a greater fiber number than the G2 group (p < 0.05) as the G3 group exhibited a higher percentage of smaller fiber and mosaic hyperplasia. In addition, a higher percentage of centered nuclei and deoxyribonucleic acid amount in the G2 group were accompanied by an increase in fiber number in the G3 group. Therefore, the muscle growth of olive flounder was influenced by continued fiber area growth and a significant number increase by mosaic hyperplasia during a specific period (G2 to G3 groups; from 512.7 to 670.3 g).  相似文献   
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