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101.
Stature is an important quantitative trait for cattle performance, which influences herd productivity. Previous studies have reported that an SNP (AC_000171.1:g.25015640G>T, rs109815800) in Pleomorphic adenoma gene 1 (PLAG1) on chromosome 14 (CHR14) is associated with bovine stature. To validate whether rs109815800 is associated with the body height of Chinese cattle, we carried out an association analysis using 558 adult cattle samples from seven populations. Then, 1038 samples from 38 Chinese cattle breeds were used to show the geographical distribution of this variant in China. The results showed that the Q allele (G allele) increased the height of cattle. Furthermore, the frequencies of Q allele in Chinese native breeds tend to decrease from northern China to southern China, and the frequency of Q allele in two Chinese beef cattle breeds is much higher than that in another 36 Chinese local cattle breeds. Our data suggest that the prevalence of the Q allele is correlated with latitude in China.  相似文献   
102.
It was earlier proposed that an important anti-cancer mechanism of plant polyphenols may involve mobilization of endogenous copper ions, possibly chromatin-bound copper and the consequent pro-oxidant action. This paper shows that plant polyphenols are able to mobilize nuclear copper in human lymphocytes, leading to degradation of cellular DNA. A cellular system of lymphocytes isolated from human peripheral blood and comet assay was used for this purpose. Incubation of lymphocytes with neocuproine (a cell membrane permeable copper chelator) inhibited DNA degradation in intact lymphocytes. Bathocuproine, which is unable to permeate through the cell membrane, did not cause such inhibition. This study has further shown that polyphenols are able to degrade DNA in cell nuclei and that such DNA degradation is inhibited by neocuproine as well as bathocuproine (both of which are able to permeate the nuclear pore complex), suggesting that nuclear copper is mobilized in this reaction. Pre-incubation of lymphocyte nuclei with polyphenols indicates that it is capable of traversing the nuclear membrane. This study has also shown that polyphenols generate oxidative stress in lymphocyte nuclei which is inhibited by scavengers of reactive oxygen species (ROS) and neocuproine. These results indicate that the generation of ROS occurs through mobilization of nuclear copper resulting in oxidatively generated DNA breakage.  相似文献   
103.
The objective of present study was to evaluate the variation in phenolic profile, β‐carotene, flavonoid contents, antioxidant and antimicrobial properties of Tagetes erecta and Tagetes patula (T. erecta and T. patula) through different in vitro assays. Antioxidant activity was determined through 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) free radical scavenging and inhibition of linoleic acid peroxidation assays and antibacterial and antifungal activities studied using the disc diffusion and resazurin microtiter‐plate assays against bacterial and fungal strains. Moreover, total phenolics (TP), total carotenoids (TC) and total flavonoids (TF) were also determined. Highest (TP 35.8 mg GAE/g) and TF (16.9 mg CE/g) contents were found in MeOH extract of T. patula. T. erecta extract showed higher TC contents (6.45 mg/g) than T. patula extract (6.32 mg/g). T. erecta exhibited the highest DPPH radical‐scavenging activity (IC50) (5.73 μg/mL) and inhibition of linoleic acid peroxidation (80.1%). RP‐HPLC revealed the presence of caffeic acid, sinapic acid and ferulic acid in Tagetes extracts, m‐coumaric acid in T. erecta whereas chlorogenic acid in T. patula extract only. Both extracts possessed promising antimicrobial activity compared to the ciprofloxacin and flumequine (+ve controls) against Bacillus subtilis and Alternaria alternate. Both extract were rich source of polyphenols exhibiting excellent biological activities.  相似文献   
104.
Immunisation of sea bream (Sparus aurata L.) broodstock with a novel vaccine mixture of Photobacterium damsela subsp. piscicida SK7 (Phdp) was performed during the period of egg development and the changes in specific and non-specific humoral immune parameters were measured. Total immunoglobulin level, specific antibody titre, anti-protease activity and lysozyme activity were significantly higher in immunised parents compared to the control. After spawning significantly higher anti-protease activity, lysozyme activity and total immunoglobulin level were detected in the eggs from immunised parents. Specific antibody titres against Phdp were only detected in the eggs from the immunised parents. The larvae from immunised parents also expressed significantly higher levels of specific and non-specific humoral immune parameters compared to the controls. A small amount of total immunoglobulin was detected in larvae decreasing gradually until day 8 post-hatching and then an increase was measured in larvae from immunised parents, whereas no immunoglobulin was detected at days 4, 6 and 8 in larvae from non-immunised parents. The specific antibody titre against Phdp was detected only in larvae from immunised broodstock until day 14 post-hatching. The higher humoral immune parameters in eggs and larvae from immunised parents in comparison to eggs and larvae from non-immunised parents, suggest transfer of maternal specific and non-specific immune factors.  相似文献   
105.
To characterize the nonuniform diameter response in a blood vessel after a given stimulus (e.g., arteriolar conducted response), frequent serial diameter measurements along the vessel length are required. We used an advanced image analysis algorithm (the "discrete dynamic contour") to develop a quick, reliable method for serial luminal diameter measurements along the arteriole visualized by intravital video microscopy. With the use of digitized images of the arteriole and computer graphics, the method required an operator to mark the image of the two inner edges of the arteriole at several places along the arteriolar length. The algorithm then "filled in" these marks to generate two continuous contours that "hugged" these edges. A computer routine used these contours to determine luminal diameters every 20 microm. Based on these diameters and on Poiseuille's law, the routine also estimated the hemodynamic resistance of the blood vessel. To demonstrate the usefulness of the method, we examined the character of spatial decay of KCl-induced conducted constriction along approximately 500-microm-long arteriolar segments and the KCl-induced increase in hemodynamic resistance computed for these segments. The decay was only modestly fitted by a simple exponential, and the computed increase in resistance (i.e., 5- to 70-fold) was only modestly predicted by resistance increase based on our mathematical model involving measurements at two arteriolar sites (Tyml K, Wang X, Lidington D, and Oullette Y. Am J Physiol Heart Circ Physiol 281: H1397-H1406, 2001). We conclude that our method provides quick, reliable serial diameter measurements. Because the change in hemodynamic resistance could serve as a sensitive index of conducted response, use of this index in studies of conducted response may lead to new mechanistic insights on the response.  相似文献   
106.
Protein kinase C (PKC) is a family of enzymes involved in a wide range of biological functions. We investigated the expression of PKC-positive cells in zebrafish embryos and larvae within the first week of development to determine the developmental profile of PKC-containing cells. Our other goal was to determine if PKC alpha was associated with Rohon-Beard neurons during the first 5 days of development, when they are reported to undergo apoptosis. First, we confirmed the specificity of the antibodies by Western blotting zebrafish brain homogenates with anti-PKC and anti-PKC alpha, and detected single protein bands of approximately 78-82 kDa in size. Immunohistochemistry showed that several types of neurons were labeled, including neurons in the trigeminal ganglia, the dorsal spinal cord, and the dorsal root ganglia. Double-labeling with anti-PKC alpha and both anti-Islet-1 and zn12 confirmed the identity of the PKC-positive cells in the brain as trigeminal neurons, and in the spinal cord as Rohon-Beard cells. Some Rohon-Beard cells were labeled with anti-PKC alpha up to 7 days post fertilization (dpf). We performed TUNEL labeling and found no correlation between TUNEL-labeled and PKC alpha-labeled Rohon-Beard cells, suggesting that PKC alpha is not involved in Rohon-Beard apoptosis. Only approximately 40% of the approximately 130 Rohon-Beard cells at 24 h postfertilization (hpf) were positively labeled for PKC. Mauthner cells were labeled by anti-PKC, but not anti-PKC alpha, suggesting that the major form of PKC within these cells was not PKC alpha.  相似文献   
107.
Hypotensive effect of novel chimeric peptides of met-enkephalin and FMRFa   总被引:2,自引:0,他引:2  
Endogenous opioid peptides like endomorphins, met-enkephalin and NPFF/FMRFamide family of neuropeptides, besides playing a role in modulation of antinociception, also affect cardiovascular system. Based on MERF, which consists of overlapping sequences of FMRFa and met-enkephalin, two chimeric peptides YGGFMKKKFMRFamide (YFa) and [D-Ala2] YAGFMKKKFMRFamide ([D-Ala2] YFa) were designed and synthesized. In this study, effect of YFa and [D-Ala2] YFa on arterial blood pressure and heart rate was evaluated in anaesthetized rats. Both YFa and [D-Ala2] YFa showed a dose-dependent fall in mean arterial pressure in dose-range of 13-78 micromol/kg. After naloxone treatment (5 mg/kg), vasodepressor effect of [D-Ala2] YFa and YFa was only partially blocked as compared to met-enkephalin. Partial blockade of vasodepressive effect of YFa and [D-Ala2] YFa by naloxone may be attributed to interaction of these chimeric peptides with receptors other than naloxone-sensitive receptors such as anti-opioid receptors, adrenergic receptors and D-analogue receptors.  相似文献   
108.
Melatonin (MLT) is a well-known free-radical scavenger, involving in the prevention of cellular damage that can lead to cancer, ageing and a variety of neurodegenerative diseases. Research on MLT-related compounds has been required to optimise the maximum pharmaceutical activity with the lowest side effects. In our ongoing research, we have synthesized new indole-based MLT analogues as potential antioxidant agents by modifying the MLT molecule. In this study, we build on previous findings, through the synthesis, characterization and in vitro antioxidant profiling of a series of new indole-based MLT analogues which possess triazole, thiadiazole and carbothioamides on the third position on the indole ring. In vitro antioxidant activity was investigated by evaluating their reducing effect against oxidation of a redox sensitive fluorescent probe and their radical scavenging activity was assessed via the DPPH assay. In addition, in vitro cytotoxic effects of newly synthesized compounds were investigated in CHO-K1 cells using the MTT assay.  相似文献   
109.
A new series of compounds derived from thiophene-2-carboxamide were synthesized and characterized by IR, 1H-NMR and 13C-NMR, mass spectrometry and elemental analysis. These compounds were further used to prepare their Co(II), Ni(II), Cu(II) and Zn(II) metal complexes. All metal(II) complexes were air and moisture stable. Physical, spectral and analytical data have shown the Ni(II) and Cu(II) complexes to exhibit distorted square-planar and Co(II) and Zn(II) complexes tetrahedral geometries. The ligand (L1) and its Cu(II) complex were characterized by the single-crystal X-ray diffraction method. All the ligands and their metal(II) complexes were screened for their in-vitro antimicrobial activity. The antibacterial and antifungal bioactivity data showed that the metal(II) complexes were found to be more potent than the parent ligands against one or more bacterial and fungal strains.  相似文献   
110.
Australian cultivar Sunco carries three adult plant stripe rust resistance genes. One of these genes corresponded to Yr18 in chromosome 7DS; the second, YrCK, was mapped on chromosome 2D. Here, we describe the characterization of the third adult plant resistance (APR) gene from Sunco. Sunco/2*Avocet S-derived lines SA65 (resistant) and SA67 (susceptible) were crossed and a recombinant inbred line F6 population was generated. Monogenic segregation among SA65/SA67-derived RIL population was demonstrated and the resistance locus was designated YrSA3. Selective genotyping using an iSelect 90 K Infinium SNP array and SSR markers located YrSA3 on chromosome 3D. Development of KASP markers for SNP loci showing association with YrSA3 allowed construction of a genetic map harboring the resistance gene. Ten KASP markers (KASP_8306, KASP_9142, KASP_10438, KASP_16434, KASP_17207, KASP_20836, KASP_23518, KASP_23615, KASP_57983 and KASP_63653), one SSR marker (gwm114b) and Lr24/Sr24 were mapped 1.8 cM distal to YrSA3. Comparison of marker data indicated that the previously named seedling stripe rust resistance gene Yr45 was located proximal to YrSA3, and therefore the latter was formally designated Yr71. Two recombinants carrying Lr24/Sr24 and Yr71 in combination were identified for use as donor sources in wheat breeding programs. The robustness of gwm114b, KASP_16434, KASP_17207 and KASP_20836 for marker-assisted selection of these genes was demonstrated through tests on 74 Australian wheat cultivars.  相似文献   
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