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71.
72.
Central regulatory mechanisms for food intake regulation vary among animals. Evidence from animal studies suggests central opioids and dopamine have prominent role on appetite regulation but their interaction(s) have not been studied in layer-type chicken. Thus, in this study six experiments designed to investigate intracerebroventricular (ICV) administration of SCH23390 (D1 like receptors antagonist), Sulpride (D2 like receptors antagonist), DAMGO (μ-opioid receptors agonist), DPDPE (δ-opioid receptors agonist), U-50488H (κ-opioid receptors agonist) on feeding behavior in 3 h food deprived neonatal layer-type chickens. In experiment 1, chicks ICV injected with control solution, SCH23390 (2.5 nmol), DAMGO (125 pmol) and their combination (SCH23390 + DAMGO). In experiment 2: control solution, SCH23390 (2.5 nmol), DPDPE (δ-opioid receptors agonist, 40 pmol) and SCH23390 + DPDPE were applied to the birds. In experiment 3, injections were control solution, SCH23390 (2.5 nmol), U-50488H (30 nmol) and SCH23390 + U-50488H. In experiments 4–6 were similar to experiments 1–3 except Sulpride (2.5 nmol) applied instead of SCH23390. Then, cumulative food intake was recorded until 120 min after injection. According to the results, ICV injection of DAMGO (125 pmol) significantly decreased food intake but co-injection of DAMGO + SCH23390 diminished DAMGO-induced hypophagia (P < 0.05). Also, SCH23390 was not able to decrease the DPDPE- and U-50488H-induced hyperphagia (P > 0.05). Furthermore, Sulpride had no role on DAMGO, DPDPE and U-50488H-induced food intake (P > 0.05). These results suggest there is an interaction between opioidergic and dopaminergic systems via μ and D1 receptors in appetite regulation in chicken.  相似文献   
73.

Introduction

While atenolol is an effective antihypertensive agent, its use is also associated with adverse events including hyperglycemia and incident diabetes that may offset the benefits of blood pressure lowering. By combining metabolomic and genomic data acquired from hypertensive individuals treated with atenolol, it may be possible to better understand the pathways that most impact the development of an adverse glycemic state.

Objective

To identify biomarkers that can help predict susceptibility to blood glucose excursions during exposure to atenolol.

Methods

Plasma samples acquired from 234 Caucasian participants treated with atenolol in the Pharmacogenomic Evaluation of Antihypertensive Responses trial were analyzed by gas chromatography Time-Of-Flight Mass Spectroscopy. Metabolomics and genomics data were integrated by first correlating participant’s metabolomic profiles to change in glucose after treatment with atenolol, and then incorporating genotype information from genes involved in metabolite pathways associated with glucose response.

Results

Our findings indicate that the baseline level of β-alanine was associated with glucose change after treatment with atenolol (Q = 0.007, β = 2.97 mg/dL). Analysis of genomic data revealed that carriers of the G allele for SNP rs2669429 in gene DPYS, which codes for dihydropyrimidinase, an enzyme involved in β-alanine formation, had significantly higher glucose levels after treatment with atenolol when compared with non-carriers (Q = 0.05, β = 2.76 mg/dL). This finding was replicated in participants who received atenolol as an add-on therapy (P = 0.04, β = 1.86 mg/dL).

Conclusion

These results suggest that β-alanine and rs2669429 may be predictors of atenolol-induced hyperglycemia in Caucasian individuals and further investigation is warranted.
  相似文献   
74.
75.
The inflammatory response to Gram-negative infection was studied in LPS responder and nonresponder C3H mice. Twenty-four hours after ascending E. coli urinary tract infection, an influx of neutrophils into the urine was observed in C3H/HeN mice (Lpsn,Lpsn); no significant neutrophil influx occurred in C3H/HeJ mice (Lpsd,Lpsd) at this time. A second peak of urinary neutrophil excretion was observed in both strains of mice approximately 6 days post-infection. The first, but not the second peak was inducible by inoculation with formalin-killed E. coli but not by Gram-positive bacteria. This finding suggested that the first peak is triggered by LPS, whereas the second peak emanates from other bacterial components which activate both LPS responder and nonresponder mice. The first peak of the inflammatory response was inversely related to bacterial clearance. C3H/HeJ mice (Lpsd,Lpsd) retained about 2000-fold more E. coli in the kidneys than C3H/HeN mice (Lpsn,Lpsn). The infection persisted despite the late-occurring influx of neutrophils in C3H/HeJ mice. These results suggest that an inflammatory response to LPS is required for the elimination of a local Gram-negative infection.  相似文献   
76.
The 9-aminoacridine-DNA binding curve is analyzed in two ways: with polyelectrolyte effects neglected and with polyelectrolyte effects included. It is found that the analysis which includes polyelectrolyte effects is consistent with the violation of neighbor exclusion displayed by diacridine complexes as observed by Atwell et al. and by Zimmerman and coworkers. However the analysis which neglects polyelectrolyte effects is inconsistent with the diacridine results. This comparison supports the necessity of including polyelectrolyte effects in the analysis of drug-DNA binding curves.  相似文献   
77.
Ri-plasmid as a helper for introducing vector DNA into alfalfa plants   总被引:1,自引:0,他引:1  
Genetic engineering of legumes and other important dicotyledonous plants is limited because of the difficulty of regenerating plants via cell culture. Since a considerable number of crop plants can be regenerated only from root culture, the introduction of foreign genes into Agrobacterium rhizogenes-induced hairy roots may expand the list of crop plants that could be genetically engineered. Here we report genetic transformation of alfalfa (Medicago sativa L.), a valuable forage legume, using a virulent strain of Agrobacterium rhizogenes containing, in addition to its Ri-plasmid, a binary vector containing a nopaline synthase gene. Plant cells transformed by this vector can be easily identified by their ability to produce nopaline. Transformed alfalfa plants were recovered from A. rhizogenes-induced hairy roots. These transgenic plants were characterized by normal leaf morphology and stem growth but a root system that was shallow and more extensive than normal. These plants were also fertile, set seeds upon self-pollination and outcrossing. Nopaline was detected in R1 progeny. Southern blot analysis confirmed the presence of multiple copies of T-DNAs from the Riplasmid in the plant genome in addition to the vector T-DNA.  相似文献   
78.
The overlapping effect of TSH and FSH on the gonad and on the thyroid gland can be demonstrated in cockerels even at the age of five weeks. These hormones influence the secretion of testosterone in a similar way and to a similar extent, while on the thyroxine level the influence of the specific hormone is more pronounced. Neonatal FSH and TSH treatment considerably decreased the basal testosterone level measured at the age of five weeks. Neonatal FSH treatment increased the basal T4 level while TSH treatment decreased it. The effect of TSH treatment administered at the age of five weeks in increasing the testosterone level was weakened after neonatal pretreatment with any iodine hormone. The effect of TSH treatment could only be inhibited by neonatal FSH pretreatment. Neonatal pretreatment with any of the trophormones caused a diminution of the T4 level augmenting of FSH and TSH administered at the age of five weeks.  相似文献   
79.
The conjugative plasmid pIJ101 and its conjugative nondeletion derivatives pIJ303 and pIJ211 were tested for their transferability between strains of Streptomyces on laboratory media and in the soil environment. Their roles in the mobilization of the cloning vector plasmid pIJ702, a nonconjugative deletion derivative of pIJ101, were also examined. Biparental and triparental crosses were performed on agar slants and in sterile soil between the plasmid donor Streptomyces lividans and several recipient Streptomyces strains previously isolated from soil. Conjugative plasmids were transferred to seven recipients in slant crosses and to three recipients in soil. Plasmids isolated from recipients showed restriction fragment patterns identical to that of the original plasmid in S. lividans. Plasmid pIJ303 was transferred less frequently in soil than on slants, and the frequency of transfer was higher at 30 degrees C than at the other temperatures examined. Transconjugant Streptomyces strains differed in their ability to maintain pIJ303. The nonconjugative plasmid pIJ702 was mobilized on agar slants into S. coelicolor 2708, which already contains a self-transmissible plasmid. Plasmid pIJ702 was also mobilized into S. flavovirens, Streptomyces sp. strain 87A, and S. parvulus on slants and in sterile soil after triparental crosses with two donors, one containing pIJ702 and the other containing either pIJ101 or pIJ211. The presence of a conjugative plasmid donor was required for the transfer of pIJ702 to S. parvulus 1234, S. flavovirens 28, and Streptomyces sp. strain 87A. Plasmid pIJ702 was always transferred in its normal, autonomous form. Chromosomal recombination also occurred in transconjugants after the transfer of pIJ702. This is the first report of gene transfer between Streptomyces strains in soil.  相似文献   
80.
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