首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 656 毫秒
1.
2.
The cardiovascular system is the first functional organ in the embryo, and its blood vessels form a widespread conductive network within the organism. Blood vessels develop de novo, by the differentiation of endothelial progenitor cells (vasculogenesis) or by angiogenesis, which is the formation of new blood vessels from existing ones. This review presents an overview of the current knowledge on physiological and pathological angiogenesis in the horse including studies on equine endothelial cells. Principal study fields in equine angiogenesis research were identified: equine endothelial progenitor cells; equine endothelial cells and angiogenesis (heterogeneity, markers and assessment); endothelial regulatory molecules in equine angiogenesis; angiogenesis research in equine reproduction (ovary, uterus, placenta and conceptus, testis); angiogenesis research in pathological conditions (tumours, ocular pathologies, equine wound healing, musculoskeletal system and laminitis). The review also includes a table that summarizes in vitro studies on equine endothelial cells, either describing the isolation procedure or using previously isolated endothelial cells. A particular challenge of the review was that results published are fragmentary and sometimes even contradictory, raising more questions than they answer. In conclusion, angiogenesis is a major factor in several diseases frequently occurring in horses, but relatively few studies focus on angiogenesis in the horse. The challenge for the future is therefore to continue exploring new therapeutic angiogenesis strategies for horses to fill in the missing pieces of the puzzle.  相似文献   

3.
1. A single nucleotide polymorphism (SNP), c.*77C>G, was found in the 3′ UTR of the chicken LPIN1 gene by DNA sequencing. In total, 860 chickens were genotyped by polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) in a F2 resource population obtained by crossing F0 Gushi chickens and Anka broilers, and the associations of this polymorphism with chicken growth, carcass, muscle fibre traits and serum biochemistry parameters were analysed.

2. Significant associations were found between the polymorphism and breast muscle fibre diameter (FDB). Comparison of the different genotypes of c.*77C>G in the F2 resource population showed that the GG genotype had significantly higher values than that of CG genotype in FDB. c.*77C>G was predicted to cause changes to multiple microRNA (miRNA) binding sites. But the total mRNA level of chicken LPIN1, LPIN1-;α and LPIN1-β in liver and muscle tissues did not show significant difference among GG, CG and CC genotypes, respectively.

3. The results suggested that chicken LPIN1 has a potential effect on muscle fibre development, but no effect on other studied traits.  相似文献   


4.
5.
Understanding how climate change and land transformation may impact the distribution and diversity of wildlife species requires landscape-level foundational biodiversity surveys. The Karoo BioGaps Project aims to provide such data and to support the scientific assessment for shale gas development projects in the Karoo basin. In this paper we present the findings of the BioGaps mammal survey, which recorded medium and large mammals across twenty-five 1 km × 1 km sampling sites within the proposed fracking footprint using camera trapping techniques. We use sample rarefaction curves, non-parametric species richness estimators and non-metric multidimensional scaling plots to explore both species richness and community structure. We also used a generalised linear model to investigate how species diversity varies with both site-specific and landscape-level predictors. A total of 38 species were recorded at the majority of sites. Longitude (z = 4.018, p = 0.0005) emerged as the best predictor of species diversity across the study area, which we suggest is linked to the clear east–west aridity gradient. Together these results reveal the cosmopolitan distribution of the mammal taxa in the Karoo and could be used to inform decision-making linked to mining activities in the area.  相似文献   

6.
1. The role of certain fish meals in the production of localised gizzard erosion is confirmed.

2. Lesions typical of gizzard erosion could be produced by the addition of histamine to the diet.

3. The amount of histamine occurring naturally in fish meal depends on the species of fish and the extent and nature of bacterial spoilage.

4. These variables may explain why histamine has not been implicated previously and also why there have not been consistent associations between the condition and geographical source or common factors in bulk consignments of the meal.  相似文献   


7.
Glaucoma and inherited retinal degeneration/dystrophy are leading causes of blindness in veterinary patients. Currently, there is no treatment for the loss of vision that characterizes both groups of diseases. However, this reality may soon change as recent advances in understanding of the disease processes allow researchers to develop new therapies aimed at preventing blindness and restoring vision to blind patients. Elucidating the molecular mechanisms of retinal ganglion cell death in glaucoma patients has led to the development of neuroprotective drugs which protect retinal cells and their function from the disastrous effects of elevated pressure. Identification of the genetic mutation responsible for inherited degenerations and dystrophies of the outer retina has enabled researchers using gene therapy to restore vision to blind dogs. Other patients may benefit from retinal transplantation, stem cell therapy, neuroprotective drugs, nutritional supplementation and even retinal prostheses. It is possible that soon it will be possible to restore sight to some blind patients.  相似文献   

8.
There is a variety of professions working with village chickens in developing countries, including farmers, veterinarians and chicken traders. People from all these occupations were involved in a participatory rural appraisal to investigate husbandry practices and trade of village chickens in Myanmar. Data were collected in two climatically different regions of the country, in the Yangon and in the Mandalay divisions. The breeding and training of fighting cocks was practised only in the Mandalay division, with well-trained birds sold for very high prices. Apart from this, chickens were raised in both regions mainly for small disposable income and were generally sold when money was needed, in particular during religious festivals. Chicken traders on bicycles, often called ‘middle men’, usually purchase birds from farmers in about 10 villages per day. Several ‘middle men’ supply birds to wealthier chicken merchants, who sell these birds at larger chicken markets. There is in general limited knowledge among farmers about the prevention of Newcastle disease via vaccination. Commercial indigenous chicken production is practised in Myanmar, but family poultry farming dominates indigenous chicken production in the country.  相似文献   

9.
10.
Hayashi  S.  Jinbo  T.  Iguchi  K.  Shimizu  M.  Shimada  T.  Nomura  M.  Ishida  Y.  Yamamoto  S. 《Veterinary research communications》2001,25(2):117-120
The concentrations of C-reactive protein (CRP) and 1-acid glycoprotein (AAG) were evaluated in 1-, 3- and 18-month-old dogs (four of each age) that had been inoculated with turpentine oil. The CRP and AAG in 3-month-old and younger dogs subjected to surgery or inoculated with either Staphylococcus aureus or a viral vaccine were also evaluated. The average CRP concentration in the sera peaked 2 days after inoculation of turpentine oil. The peak CRP concentrations in 3- and 18-month-old dogs were significantly (p<0.05) greater than those in 1-month-old dogs. The average AAG concentration in the sera peaked 4 days after inoculation of turpentine oil. No significant difference was found in AAG concentrations between any of the age groups. When experimentally inoculated with S. aureus or subjected to oophorohysterectomy, the CRP and AAG concentrations increased in 3-month-old dogs, but they increased little in 1-month-old dogs. The CRP and AAG in dogs inoculated with the viral vaccine did not increase. In dogs with fractures or subjected to percutaneous gastrostomy, the CRP and AAG concentrations correlated with the condition of dogs.  相似文献   

11.
Interleukin-1β (IL-1β) may regulate ovarian physiology. In this study, the influence of IL-1β on secretory activity within the corpora lutea (CL) of cyclic and gravid pigs was determined in vitro during different stages of the CL lifespan, e.g. on Days 10-11, 12-13 and 15-16 of the oestrous cycle and pregnancy. IL-1β (10 ng/ml) increased prostaglandin E2 (PGE2) secretion from CL of the cyclic and gravid pigs during studied days of the oestrous cycle and pregnancy. Increase (P < 0.05) of prostaglandin F2α (PGF2α) in IL-1β-treated CL was demonstrated only on Days 10-11 of the oestrous cycle. More potent stimulatory effect of IL-1β on PGE2 than PGF2α secretion resulted in the enhancement of the PGE2:PGF2α ratio in cyclic and early pregnant CL. IL-1β increased (P < 0.05) progesterone (P4) secretion only in gravid CL and had no effect on oestradiol-17β (E2) release. Expression of cyclooxygenase-2 (COX-2) mRNA was stimulated (P < 0.05) in IL-1β-treated cyclic and gravid CL. Expression of prostaglandin synthase mRNAs in response to IL-1β did not increase. In conclusion, IL-1β modulates PGE2, PGF2α and P4 secretion from porcine CL, depending on luteal stage and the surrounding hormonal milieu. The cytokine may act locally in porcine CL for luteotrophic support throughout the PGE2-mediated synthesis and secretion.  相似文献   

12.
13.
14.
The establishment of pregnancy is a complex process that requires a well-coordinated interaction between the implanting conceptus and the maternal uterus. In pigs, the conceptus undergoes dramatic morphological and functional changes at the time of implantation and introduces various factors, including estrogens and cytokines,interleukin-1β2(IL1 B2), interferon-γ(IFNG), and IFN-δ(IFND), into the uterine lumen. In response to ovarian steroid hormones and conceptus-derived factors, the uterine endometrium becomes receptive to the implanting conceptus by changing its expression of cell adhesion molecules, secretory activity, and immune response. Conceptus-derived estrogens act as a signal for maternal recognition of pregnancy by changing the direction of prostaglandin(PG) F2αfrom the uterine vasculature to the uterine lumen. Estrogens also induce the expression of many endometrial genes,including genes related to growth factors, the synthesis and transport of PGs, and immunity. IL1 B2, a pro-inflammatory cytokine, is produced by the elongating conceptus. The direct effect of IL1 B2 on endometrial function is not fully understood. IL1 B activates the expression of endometrial genes, including the genes involved in IL1 B signaling and PG synthesis and transport. In addition, estrogen or IL1 B stimulates endometrial expression of IFN signaling molecules,suggesting that estrogen and IL1 B act cooperatively in priming the endometrial function of conceptus-produced IFNG and IFND that, in turn, modulate endometrial immune response during early pregnancy. This review addresses information about maternal-conceptus interactions with respect to endometrial gene expression in response to conceptus-derived factors, focusing on the roles of estrogen and IL1 B during early pregnancy in pigs.  相似文献   

15.
The inhibition of HIV expression in vitro by a cocktail of the -chemokines MIP-1, MIP-1 and RANTES provided the initial evidence that HIV utilizes chemokine receptors as co-receptors for infection of cells. Bovine immunodeficiency virus (BIV), a lentivirus, infects a wide variety of leukocyte populations, but the cellular receptor(s) utilized by this virus for infection of cells is not known. The purpose of this study was to determine whether MIP-1, MIP-1 and RANTES affect BIV expression in vitro, as a prelude to identifying the cellular receptors utilized by this virus. Fetal bovine lung (FBL) cells were pretreated with serial dilutions of a cocktail of the chemokines, and then the cells were infected with BIV. Virus expression in these cells was determined by counting the syncytia that had developed in the cultures by five days after infection. A significant decrease in syncytium formation, corresponding to increasing concentrations of the chemokines, was the result. Reacting the chemokines with chemokine-specific neutralizing antibodies prior to treatment of the cells neutralized the effect of the chemokines on virus replication in a dose-dependent manner, restoring viral expression to a level similar to that of untreated cells. The presence of a CCR5 homologue on the surface of FBL cells was confirmed using an anti-CCR5 monoclonal antibody and FACS analysis. Collectively, these data provide preliminary evidence that BIV may utilize the CCR5 receptor for infection of cells in vitro, but additional studies are necessary to confirm this.  相似文献   

16.
This paper was carried out on the morphological character of the test and epididymis of three types of yak bull age 6,12,18,24 months old (1/2 wild yak, cross 1/2 wild yak and domestic yak). The results showed that the weight and size of testes and epidiymis was increased with the age which was hardly affected by imbalance of food supply during the cold and warm seasons. The development were similar for three kinds of yak at the same age(P>0.05).  相似文献   

17.

Background

The study aimed at examining hypoxia-inducible factor (HIF)1α expression in adenocarcinomas and adenomas in bitches in regard to tumour malignancy grade, proliferation, apoptosis and vascularisation. Therefore, paraffin sections of 15 adenomas and 64 adenocarcinomas sampled from 79 dogs aged 6 to 16 years were analysed.

Results

A significantly higher HIF-1α expression was noted in adenocarcinomas in comparison to adenomas (P < 0.0004). Moreover, HIF-1α expression in adenocarcinomas correlated positively with tumour malignancy grade (r = 0.59, P < 0.05), Ki-67 antigen expression (r = 0.43; P < 0.0005), TUNEL-positive cells (r = 0.62, P < 0001) and tumour vascularity measured by quantification of vessels characterized by the expression of von Willebrand Factor (r = 0.57, P < 0.05).

Conclusion

Results of this study indicate a similar biological role of HIF-1α in dogs and in humans, which may confirm suitability of the animal model in investigations on progression of tumours in humans.  相似文献   

18.
To identify factors that control coat color in Akita-inu dogs, we sequenced all the exons of the melanocortin 1 receptor (MC1R), β-defensin103 (CBD103) and agouti signaling protein (ASIP) genes of dogs with four distinct coat colors, namely, brindle, sesame, red and white. Then we examined correlations among specific alleles and coat color. In the case of the MC1R gene, all white dogs were homozygous for a nonsense mutation, R306ter, while brindle, sesame, and red dogs had at least one R306 allele. In the case of the CBD103 gene, all brindle dogs were heterozygous for the G23del mutation (deletion of codon 23, encoding glycine), while all sesame and red dogs were homozygous for G23. In the case of the ASIP gene, all dogs, regardless of coat color, had at least one S82 H83 allele. A missense mutation in the ASIP gene, P87L, was identified for the first time in some Akita-inu dogs but was not associated with any specific coloration. Our results indicate that the 2 key mutations, R306ter in the MC1R gene and G23del in the CBD103 gene, are associated with the phenotypic discriminations among brindle, red/sesame, and white coats, while no mutation that might potentially be associated with the discrimination of a sesame coat from a red coat is present in the coding sequences of these three genes.  相似文献   

19.
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号