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1.
Abstract

Macrophage aggregate (MA) morphometry and pigment composition are believed to be dependent on the species, age, and health status of the fish. The aim of this study was to characterize a “normal” morphometry baseline of spleen and kidney MAs in blue gourami Trichogaster trichopterus and freshwater angelfish Pterophyllum scalare. Three size-classes of clinically normal fish were analyzed. Blue gourami and freshwater angelfish were obtained from three local ornamental fish farms; for each size-class, 10 fish from each farm were analyzed. Hematoxylin- and eosin-stained tissue sections were analyzed by light microscopy at 100× magnification and an image analysis program. The percentage of tissue occupied by MAs, MA size, and MA number were calculated on three arbitrarily selected fields of view from each spleen and kidney. In clinically normal blue gourami, increases in the percentage of tissue occupied by MAs and in MA size were associated with an increase in fish size, but in clinically normal angelfish no correlation was observed. Furthermore, in angelfish, a high variability in MA morphometry was observed, even among fish from the same sample group. In both species, a significant difference in the value of the morphometric parameters was observed among farms. Because iridoviruses inhibit macrophage activity and (possibly) proliferation, MAs in 25 clinical cases of iridovirus-infected blue gourami were analyzed. Preliminary data indicate that in iridovirus-infected blue gourami, there is a decrease in MA size and MA number compared with those of healthy fish.  相似文献   

2.
D-serine is a well-known activator of N-methyl-D-aspartate receptors; however, little is known about the teratogenic effects of D-serine overdose during early embryonic development. Here, we used zebrafish as a model to test toxicity and teratogenicity, since they have transparent eggs, making the organogenesis of zebrafish embryos easier to be observed. After D-serine injection (100–1000 ppm), the most evident defective phenotypes were bent trunk phenotypes, including malformed somite boundary, twisted body axis and shorter body length. As the injection dosages increased, the rates of embryos with bent trunk phenotypes decreased (0% for 0 ppm, n=573; 59.9~84.3% for 100–1000 ppm of D-serine, n=383–451). In addition, D-serine-injected embryos exhibited significantly reduced the frequencies of spontaneous in-chorion contraction (21.7 for 0 ppm vs. 18.3–0.9 for 100–1000 ppm D-serine, n=30) in comparison with mock-treated controls (0 ppm). Subtle changes are easily observed by staining with specific monoclonal antibodies F59, Znp1, Zn5 and α-bungarotoxin to detect morphological changes in muscle fibers, primary motor axons, secondary motor axon projections and neuromuscular junctions, respectively. Our data show that overdose of D-serine leads to misalignment of muscle fibers and motor neuron defects, especially secondary motor neuron axonal growth defects.  相似文献   

3.
In this study, African Catfish (also known as Sharptooth Catfish) Clarias gariepinus were exposed to sublethal concentrations of fenthion of 2.0, 4.0, and 8.0 mg/L for 21 d and allowed to recover for 7 d to investigate the potential for hematological changes. Whole blood was sampled on days 1, 7, 14, and 21 postexposure and after a 7-d recovery period. During exposure, fenthion caused a reduction in red blood cell counts, hemoglobin concentration, and packed cell volume. There was an increase in white blood cell counts but no significant difference in mean corpuscular hemoglobin concentration, mean corpuscular volume, and mean corpuscular hemoglobin. Both increases and decreases were observed in white blood cell differentials. After the 7-d recovery period, both increases and decreases were observed in the hematological parameters. These results reveal that sublethal concentrations of fenthion can cause hematological alterations in African Catfish and that the substance should be used with caution.

Received October 20, 2015; accepted May 4, 2016 Published online October 20, 2016  相似文献   


4.
旨在研究细菌脂多糖(LPS)急性暴露对小鼠睾丸及其功能的影响。将健康雄性小鼠随机分为4组:对照组(Control)、1.25 mg·kg-1 LPS组、2.5 mg·kg-1 LPS组和5.0 mg·kg-1 LPS组,对照组腹腔注射200μL生理盐水,其余3组注射等体积含不同剂量的LPS,作用12 h。收集睾丸组织制作石蜡切片,染色后观察其病理变化,记录体重、睾丸和附睾指数,并测定精子品质相关指标,用RT-qPCR法检测炎症相关基因TNF-α、IL-6、GAS6和TGF-β1的转录,同时用ELISA检测血清中睾酮(T)的含量。结果表明,与对照组相比,LPS急性暴露时,以剂量依赖性方式降低小鼠体重(P<0.05或P<0.01),同时显著降低睾丸指数(P<0.05或P<0.01)、精子密度(P<0.01)及精子活力(P<0.05或P<0.01),增加精子畸形率(P<0.05或P<0.01);使睾丸组织发生不同程度的病理学变化,表现在生精细胞凋亡,曲细精管管腔增大,精子数量减少等;导致血清中睾酮(T)的含量显著下降;另外,LPS还呈剂量依赖方式增加促炎因子TNF-α和IL-6及抑制抗炎因子GAS6和TGF-β1的转录。结果提示,细菌LPS急性暴露可通过破坏机体中炎症因子的平衡,使睾丸组织受到损伤从而导致生精障碍。  相似文献   

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为探究死亡受体Fas在镉暴露致大鼠大脑皮质自噬体形成中的作用,将24只21日龄雄性SD大鼠随机分为4组,分别为对照组、镉组、镉与对照病毒共处理组、镉与Fas基因沉默病毒共处理组。试验期间,对照组大鼠自由饮用纯净水,病毒处理组大鼠于第1天以每只1.4×1011vg的剂量通过尾静脉注射相应病毒,4周后镉染毒组大鼠自由饮用镉水(50 mg·L-1),持续90 d。试验结束后,透射电镜观察大脑皮质中自噬体数量,Western blot检测大脑皮质细胞外信号调节激酶1/2(Erk1/2)、p-Erk1/2、自噬相关蛋白7(ATG7)、自噬相关基因(Beclin-1)、微管相关蛋白1轻链3(LC3)蛋白表达水平,免疫荧光染色检测LC3表达水平。结果显示,镉暴露增加大脑皮质中自噬体数量,极显著激活Erk1/2并上调ATG7、Beclin-1、LC3蛋白表达水平(P<0.01);Fas基因沉默抑制镉引起的自噬体数量增加,极显著抑制镉致Erk1/2激活及ATG7、Beclin-1、LC3蛋白表达水平升高(P<0.01)。结果表明,Fas通过激活Erk1/2参与镉致大鼠大脑皮质自噬体形成。  相似文献   

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Summary Susceptible Ankole (Sanga:Bos indicus/Bos taurus) and crossbred Ankole x Jersey (B. taurus) and Ankole x Sahiwal (B. indicus) cattle derived from a farm in Rwanda with no recent history of theileriosis, were infected withTheileria parva stocks from Rwanda either by feeding infectedRhipicephalus appendiculatus ticks on the ears, inoculation of tick derived stabilate or natural exposure to tick challenge. The Ankole cattle originated from local stock born and bred in East Coast fever (ECF) endemic areas of Rwanda. Disease, followed by spontaneous recovery, was observed in 49 of the 72 Ankole cattle after infection withT. parva (68%); the other 23 animals (32%) died of ECF. In contrast 21 of the 33 infected crossbred cattle (64%) died of ECF. It is concluded that the partialTheileria tolerance of the Ankole is, to a great extent, genetic. The basis of this partial tolerance seems to be their ability to limit the explosive multiplication of macroschizonts during the acute phase of the disease.
Resumen Se infectó ganado Ankole susceptible (Sanga:Bos indicus/Bos taurus) y ganado cruzado Ankole x Jersey (Bos taurus) y Ankole x Sahiwal (Bos indicus) proveniente de una finca en Rwanda sin historia reciente de theileriosis, conTheileria parva procedente de Rwanda, mediante la adhesión en la oreja deRhipicephalus appendiculatus infectado, inoculación de estabilados derivados de garrapatas, o exposición natural a la enfermedad a través del vector. El ganado Ankole era originario de un área endémica de theileriosis en Rwanda. Se observó la enfermedad seguida de recuperación, en 49 de 72 animales Ankole infectados conT. parva (68%); los otros 23 animales murieron (32%). En contraste, 21 de los 33 animales cruzados infectados (64%), murieron. Se concluye, que la tolerancia parcial del ganado Ankole es de origen genético. Las bases de ésta tolerancia genética, parece debida a la habilidad para limitar en cierto modo la multiplicación explosiva de macroesquizontes, durante la fase aguda de la enfermedad.

Résumé On a infecté du bétail sensible, de race Ankolé (Sanga:Bos indicus/Bos taurus) et des croisés Ankolé x Jersey (B. taurus) et Ankolé x Sahiwal (B. indicus), provenant d'une ferme au Rwanda sans cas récents de theilériose, avec des souches deTheileria parva du Rwanda, par l'application de tiques (Rhipicephalus appendiculatus) infectées sur les oreilles, par inoculation de stabilat de tiques infectées ou par l'exposition à un challenge naturel de tiques. La souche d'Ankolé était originaire du cheptel local Rwandais, né et élevé dans les régions où la theilériose est endémique. La maladie suivie par la guérison spontanée fut observée dans 49 des 72 Ankolés (68%), les autres 23 animaux (32%) ont succombé à la theilériose. Par contre 21 des 33 croisées infectées (64%) ont succombé à la theilériose. Nous concluons que la tolérance partielle des Ankolés contre la theilériose, est génétique. La base de cette tolérance semble être leur capacité de limiter la multiplication explosive des macroschizonts pendant la phase aigu de la maladie.
  相似文献   

8.
Veterinary Research Communications - Cabassi, E., 2007. The immune system and exposure to xenobiotics in animals. Veterinary Research Communications, 31(Suppl. 1), 115–120  相似文献   

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设置苹果(Malus domestica Borkh.)园清耕与间作白三叶(Tri folium repens L.)2个处理,分析其对果园土壤机械稳定性团聚体和水稳性团聚体及团聚体稳定性、水稳性团聚体有机碳含量的影响.结果表明:间作白三叶增加了果园土壤水稳性团聚体平均重量直径(MWD),降低了团聚体破坏率(PAD),显著提高了0~20 cm土层>0.25 mm水稳性团聚体的含量及其稳定性(P<0.05),但未对果园土壤中>0.25 mm粒级机械稳定性团聚体含量产生明显影响;间作白三叶改变了果园土壤团聚体有机碳含量与分布,显著增加了0~20 cm土层>0.25 mm水稳性团聚体有机碳含量(P<0.05),其中0.5~0.25 mm粒级水稳性团聚体有机碳含量增幅最大,1~0.5 mm粒级增加幅度较小.间作白三叶可显著提高果园0~20 cm土层水稳性团聚体含量及其稳定性、团聚体有机碳含量(P<0.05),且对不同粒级水稳性团聚体及团聚体碳含量的影响表现出明显差异.  相似文献   

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植物和土壤微生物是土壤团聚体黏合物和养分的重要来源,因此土壤团聚体组成及其养分库的变化可指示生态系统退化过程。本文在长江源区根据植被群落特征选取未退化、中度和严重退化高寒草甸,研究其土壤中大团聚体(>250μm)、微团聚体(55~250μm)和游离态粉粒黏粒(<55μm)含量、不同粒级团聚体碳氮磷含量及储量随草地退化的变化特征,并分析了植物和微生物活动与这些变化特征的关系。结果表明:未退化和中度退化高寒草甸土壤以微团聚体为主。退化使高寒草甸大团聚体和微团聚体碳氮含量及储量显著下降,但磷含量及储量未发生显著变化。游离态粉粒黏粒氮磷储量在严重退化高寒草甸显著增加。各团聚体碳氮含量与地上生物量和微生物量碳正相关,磷含量与微生物量碳负相关。本研究表明植物及受其影响的土壤微生物变化是造成高寒草甸退化后不同团聚体碳氮磷库变化的主要原因。  相似文献   

12.
给草鱼腹腔注射细微炭粒(墨汁)后不同时间取样,比较观察了草鱼胸腺、肝、脾、头肾和肾组织中巨噬细胞集结(m acrophage aggregation , M A)状况及相应组织的变化。结果表明,在头肾和脾组织中, M A 的数量和体积均较肝和肾中的多而大,胸腺中所产生的 M A 数量较肝和肾中的少,体积也小;注射墨汁后 1~3 周内,在胸腺、头肾、肝和脾组织中, M A 的数量和体积均有不同程度的增加,但在注射墨汁后第 4 周的肾组织中, M A 的体积缩小而且密度降低,同时肾组织结构有逐渐恢复的趋势,可能是由于 M A 分解后通过肾小球和肾小管排泄到膀胱或体外的缘故。对草鱼 M A 的组织分布、排除等分析认为, M A 可作为草鱼非特异细胞防御作用的解剖学和细胞学的一种生物标记。  相似文献   

13.
Geminin是一种25kD的核蛋白,在细胞增殖、细胞分化、胚胎发育以及肿瘤发生等多方面均发挥着重要作用。在不同发育阶段,Geminin在不同的区域表达,可作为抑制因子或是诱导因子参与胚胎发育的调节。而通过建立相关geminin的转基因斑马鱼来调控其在体内的表达上调或下调,是研究geminin功能的一种常用方法。主要对geminin相关的结构、功能及其在胚胎发育方面作用的研究进展以及相关的实验技术进行了综述。  相似文献   

14.
Newborn and young pups up to the age of 15 days were exposed to E. cuniculi, either by keeping the pups in cages together with orally inoculated foster-mothers and their offspring, or by oral inoculation with E. cuniculi spores. A majority of pups appeared sero-positive to E. cuniculi with the india-ink immuno-reaction from 35 to 87 days post exposure; spores of E. cuniculi were detected in organs of some of the animals. The non-inoculated pups kept together with the orally inoculated pups became seropositive from 49 to 129 days after the oral inoculations. However, the exposure of newborn and young pups failed to induce clinical encephalitozoo-nosis, and when killed at the time of pelting the body weights and fur quality appeared to be within the normal range in all exposed foxes. No macroscopic lesions were detected in the various organs. Histologically focal interstitial nephritis occurred in the great majority of the seropositive animals. Meningoencephalitis was seen in some of the foxes, whereas slightly thickened walls of some arteries, mainly in the myocardium, were found in a few animals. The lesions of the brain and kidneys seem to be very similar to those seen in chronic cases of rabbit encephalitozoonosis. Polyarteritis nodosa and severe encephalitis and interstitial nephritis with extensive proliferations of plasma cells, which are almost constant findings in cases of clinically diseased foxes, were not detected in any of the subclinically infected animals. Various factors that might be of significance in the pathogenesis of the disease are discussed, and it is concluded that intrauterine infection of the pups via the transplacental route appears to be an essential supposition for the establishment of clinical fox encephalitozoonosis.  相似文献   

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为探讨芝麻素对氟暴露斑马鱼生长性能及肠组织形态学的影响,本试验将720尾斑马鱼随机分为6组,分别为对照组(CK)、芝麻素Ⅰ组(1 g,S1)、芝麻素Ⅱ组(2 g,S2)、80 mg/L氟暴露组(F)、80 mg/L氟暴露+芝麻素Ⅰ组(1 g,FS1)、80 mg/L氟暴露+芝麻素Ⅱ组(2 g,FS2),每组3个重复,每个重复40尾。并在试验第45、90天测量各组斑马鱼体长、体重、增长率(LGR)、增重率(WGR)、特定生长率(SGR),组织学法观察各组斑马鱼的肠组织结构,用Imageproplus图像软件系统测量肠道绒毛高度。结果发现,第45天时,与CK组相比,F组斑马鱼体重显著下降(P<0.05),添加芝麻素(FS1和FS2组)对其有一定改善作用但差异不明显(P>0.05)。试验第90天时,与CK组相比,F组斑马鱼体重和体长显著下降(P<0.05),添加芝麻素(FS1和FS2组)可一定程度上改善这种负作用,但效果并不显著(P>0.05)。在45和90 d时,F组LGR、WGR、SGR较对照组均下降,而FS1和FS2组较F组呈上升趋势。斑马鱼肠道组织切片观察发现,芝麻素还可在一定程度上改善氟暴露对斑马鱼肠道组织造成的负面效应。综上所述,芝麻素可对氟致斑马鱼生长及肠道组织的毒性效应产生一定缓解作用。  相似文献   

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Articular cartilage exposure and immediate postoperative stability provided by three medial surgical approaches in canine cadaver elbows were compared. The approaches evaluated were a desmotomy of the medial collateral ligament (DMCL) that included a tenotomy of the pronator teres muscle, a longitudinal myotomy of the flexor carpi radialis (MFCR), and an osteotomy of the medial epicondyle (OME). Nondestructive biomechanical testing was performed before the surgical approach and repeated after surgery. The stiffness at 13 valgus deviation of the elbow and energy absorption up to 13 valgus deviation of the elbow were determined from the pre-operative and postoperative torque-rotation curves. The perimeters of the ulnar and humeral articular cartilage that were visualized through the approach were scored with a dental pick. Latex casts were made of articular surfaces of the elbow. The humeral and ulnar articular exposures were determined by computerized planimetric analysis of latex cast photocopies. The humeral cartilage exposure of the OME approach was significantly greater than either the MFCR or DMCL approaches. The DMCL approach provided a significantly greater humeral cartilage exposure than the MFCR approach. All three approaches provided statistically similar percentages of ulnar cartilage exposure. The stiffness and energy absorption of the OME and MFCR approaches were similar and significantly greater than the DMCL approach. The OME approach provided the best combination of exposure and immediate postoperative stability.  相似文献   

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