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The present study was designed to examine the effects of cell-cycle synchronization protocols, such as confluent, roscovitine treatment and serum starvation, in bovine foetal fibroblasts on synchronization accuracy at G0/G1, viability, apoptosis, necrosis and ploidy for use as a nuclei donor. The cells in 5-10 passages were randomly allocated into three treated groups. Cells were cultured either in Dulbecco's modified Eagle's medium (DMEM) + 10% foetal bovine serum (FBS) until 90% confluent (group 1, confluent), in DMEM + 10% FBS + 30 microM roscovitine for 12 h (group 2, roscovitine), or in DMEM + 0.5% FBS for 5 days (group 3, serum starvation). Most of the cells (>80%) in all groups were arrested at the G0/G1 stage. Although the rates did not differ, cells in group 1 showed an increased cell population arrested at the G0/G1 phase. Significantly (p < 0.05) higher rates of apoptosis occurred in group 3 than in group 1 and 2 (10% vs 6% and 6%, respectively). No differences in chromosomal abnormality were observed among groups. However, by increasing the number of cell culture passages up to 15, significantly (p < 0.05) higher chromosomal abnormality was observed than in 5 and 10 passages (39% vs 28% and 23%, respectively) in group 1. The results clearly indicated that bovine foetal fibroblasts could be effectively synchronized at G0/G1 stages by all the three different treatments, confluent, roscovitine and serum starvation. However, cells in confluent showed reduced apoptosis and necrosis when they underwent 5-10 passages, exhibiting increased percentage of cells with stable chromosome diversity. Hence, cells in confluent merit further studies before they could be used as nuclear donors.  相似文献   
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This study was conducted to evaluate the effects of dietary supplementation of Barodon, an anionic alkali mineral complex, on growth, feed utilization, humoral innate immunity and disease resistance of olive flounder. A basal experimental diet was used as a control and supplemented with 0.1, 0.2, 0.3, 0.4, or 0.5% Barodon. Triplicate groups of fish (26.4 ± 0.2 g) were fed one of the diets to apparent satiation twice daily for 10 wk. The growth performance was enhanced (P < 0.05) linearly and quadratically in fish fed diets containing Barodon compared with that in fish fed the control. Feed utilization was significantly improved by Barodon supplementation. Serum lysozyme and antiprotease activities were increased quadratically in Barodon fed groups. Also, significantly higher superoxide dismutase activity was found in Barodon‐fed fish. Dietary supplementation of 0.1–0.3% Barodon resulted in significant enhancement of fish disease resistance against Streptococcus iniae. The findings in this study indicate that dietary supplementation of Barodon can enhance growth, feed utilization, innate immunity, and disease resistance of olive flounder and that the optimum level seems to be 0.1% in diets.  相似文献   
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BackgroundThe microsporidian parasite Nosema ceranae is a global problem in honeybee populations and is known to cause winter mortality. A sensitive and rapid tool for stable quantitative detection is necessary to establish further research related to the diagnosis, prevention, and treatment of this pathogen.ObjectivesThe present study aimed to develop a quantitative method that incorporates ultra-rapid real-time quantitative polymerase chain reaction (UR-qPCR) for the rapid enumeration of N. ceranae in infected bees.MethodsA procedure for UR-qPCR detection of N. ceranae was developed, and the advantages of molecular detection were evaluated in comparison with microscopic enumeration.ResultsUR-qPCR was more sensitive than microscopic enumeration for detecting two copies of N. ceranae DNA and 24 spores per bee. Meanwhile, the limit of detection by microscopy was 2.40 × 104 spores/bee, and the stable detection level was ≥ 2.40 × 105 spores/bee. The results of N. ceranae calculations from the infected honeybees and purified spores by UR-qPCR showed that the DNA copy number was approximately 8-fold higher than the spore count. Additionally, honeybees infected with N. ceranae with 2.74 × 104 copies of N. ceranae DNA were incapable of detection by microscopy. The results of quantitative analysis using UR-qPCR were accomplished within 20 min.ConclusionsUR-qPCR is expected to be the most rapid molecular method for Nosema detection and has been developed for diagnosing nosemosis at low levels of infection.  相似文献   
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Hepatitis E outbreaks are a serious public health concern in developing countries. The disease causes acute infections, primarily in young adults. The mortality rate is approximately 2%; however, it can exceed 20% in pregnant women in some regions in India. The causative agent, hepatitis E virus (HEV), has been isolated from several animal species, including pigs. HEV genotypes 3 and 4 have been isolated from both humans and animals, and are recognized as zoonotic pathogens. Seroprevalence studies in animals and humans indirectly suggest that HEV infections occur worldwide. The virus is primarily transmitted to humans via undercooked animal meats in developed countries. Moreover, transfusion- and transplantation-mediated HEV infections have recently been reported. This review summarizes the general characteristics of hepatitis E, HEV infection status in animals and humans, the zoonotic transmission modes of HEV, and HEV vaccine development status.  相似文献   
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The effects of electroacupuncture (EA) on intraocular pressure (IOP) and hemodynamic parameters were evaluated in isoflurane anesthetized 10 (5 males, 5 females) normal mongrel dogs (8.1-9.8 kg, 6-8 years old). After determination of baseline IOP and hemodynamic parameters (cardiac index, systolic arterial pressure, diastolic arterial pressure, heart rate and systemic vascular resistance index), EA was applied at 3 acupoints (LI-4, LIV-3 and GB-37) for 20 min. After the EA treatment, IOP was significantly decreased in the both eyes (p<0.05). However, there were not significant differences in hemodynamic parameters between those of before and after EA treatment. From these results, the EA treatment at LI-4, LIV-3 and GB-37 would be considered one of the valuable methods for the IOP treatment in dogs.  相似文献   
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Three dogs were presented to us for evaluation of cardiac problems. Electrocardiographic recordings revealed severe tachyarrhythmia and atrial fibrillation with ventricular tachycardia in 2 of the 3 dogs. The echocardiographic findings of the 3 dogs revealed markedly decreased fractional shortening and a marked increase in E-point septal separation. Based on the results of electrocardiographic and echocardiographic evaluation, the 3 dogs were diagnosed as dilated cardiomyopathy (DCM). The dogs were treated with conventional cardiac medication, but cardiac function did not improve and the clinical signs remained. We subsequently attempted treatment with granulocyte-colony stimulating factor (G-CSF; 10 microg/kg, subcutaneously). The specific purpose of G-CSF therapy for DCM was to improve cardiac function and a significant improvement in cardiac function was confirmed. The three dogs had no treatment side effects. This case report suggests that G-CSF might have therapeutic effects for medically refractory DCM in dogs.  相似文献   
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Recent droughts in the humid southeastern United States have focused attention on the need for and use of supplemental irrigation. Total annual rainfall amounts are sufficient for most crops in the region. However, erratic distribution of rainfall and the low water-holding capacities of most soils in the region cause frequent drought stresses in many crops. An on-farm study was conducted in southeastern Alabama to evaluate the effects of farmers' irrigation scheduling decisions on soil moisture variations in peanut fields irrigated with center-pivot irrigation systems. The study showed that the way irrigation was practiced in this high rainfall area often caused soil moisture deficit (SMD) level higher than the desired SMD limit during over 20% of the 140-day growing season. This is partially due to farmers' tendency to delay irrigation in anticipation of rainfall which may or may not occur, as rainfall during the growing season is often erratic and local. In contrast SMD in non-irrigated fields was higher than the SMD limit for half of the growing season.Abbreviations SMD soil moisture deficit - ET evapotranspiration - Reff effective rainfall - WHC water holding capacity  相似文献   
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