马氏珠母贝IGF2BP1基因的鉴定及对矿化相关基因表达的影响

胰岛素样生长因子2结合蛋白( IGF2BPs)是一种重要的RNA代谢调控因子,涉及多个不同的生物学过程。本研究鉴定了一个马氏珠母贝IGF2BP1基因,命名为PfIGF2BP1-1,该基因cDNA全长为7348 bp,ORF长 1818 bp,编码605个氨基酸。多序列比对和系统进化分析表明,PfIGF2BP1-1有2个RRM结构域和4个KH结构域,与其他物种来源的IGF2BPs同源。实时荧光定量PCR结果显示,PfIGF2BP1-1 在马氏珠母贝的8个组织中均有表达,在肌肉组织表达最高,其次为足和外套膜组织。利用pET-32a 原核表达载体构建了含有PfIGF2BP1-1成熟多肽区的重组质粒并成功表达蛋白。在IPTG浓度为0.5 mmol/L,37 ℃培养8 h的条件下诱导表达PfIGF2BP1-1蛋白最佳。PfIGF2BP1-1蛋白刺激马氏珠母贝外套膜原代细胞,引起壳基质蛋白基因Accbp、MSI7、Nacrein的表达水平显著上升(p < 0.05),表明PfIGF2BP1-1蛋白可诱导壳矿化相关基因的表达参与马氏珠母贝的生物矿化过程。     

散鳞镜鲤、团头鲂及其杂交F1肌肉营养成分的比较

采用生化分析方法对散鳞镜鲤、团头鲂及其杂交F1肌肉的营养成分进行了测定并比较。结果表明，交杂种F1肌肉中的水分含量为77．89％、灰分含量为5．52％，均低于亲本；脂肪含量为4．77％，高于团头鲂，低于散鳞镜鲤；F1的氨基酸含量为77．89％，低于双亲，但大多成分含量与散鳞镜鲤相当。在总体水平上，杂交种品质得到初步的改良。     

Paralytic shellfish poisoning toxin analysis of the genus <Emphasis Type="Italic">Alexandrium</Emphasis> (Dinophyceae) occurring in Korean coastal waters

ABSTRACT:   Paralytic shellfish poisoning (PSP) toxins produced by Alexandrium isolates from Korea were analyzed by high-pressure liquid chromography. Species designation of the regional isolates was determined by morphological criteria and ribotyping inferred from sequences of the 28S rDNA D1-D2 region. Toxin analysis performed at the exponential growth phase, revealed that the two strains of A. fraterculus were non-toxic, while the strains of A. tamarense and A. catenella were toxic. Toxic isolates DPC7 and DPC8 of A. catenella produced GTX1, 2, 3, 4, 5, dcGTX2, 3, C1, 2, neoSTX and STX with trace or non-detectable levels of C3 and C4, while isolates UL7, KDW981, SJW97043, SJW97046, KJC97111 and KJC97112 of A. tamarense produced GTX1, 2, 3, 4, dcGTX3, C1, 2, neoSTX with trace or non-detectable levels of C3, 4, dcSTX and STX, and no GTX5 and dcGTX2. The major toxins produced by A. catenella were C1 +2, and those of A. tamarense were C1 +2 and GTX4 in most of the isolates. A. tamarense strains other than SJW97046 produced a relatively high proportion of carbamate toxins, reflecting the high toxicity scores of shellfish intoxication in sampled coastal areas. Two representative toxic isolates, A. tamarense SJW97043 and A. catenella DPC7, were cultured for 30 days in batch mode and subjected to toxin analysis at 5-day intervals. Comparison of toxin productivity in terms of total toxin content, toxin components, and their variations with culture age revealed marked differences between the two strains.     

电磁场对几种淡水鱼鱼苗胚胎期的出苗率、抗温变能力和后期生长速度的影响

对蟾蜍、鱼类胚胎的质子核磁弛豫的研究发现,在胚胎发育期中的神经胚期出现质子纵向核磁弛豫时间T_1值为一极大值。几年来,我们用各种物理手段对蟾蜍和几种淡水鱼胚胎在不同发育期进行物理刺激,发现在鱼类胚胎早期和神经期接受较强电场或磁场刺激后,不仅其后期生长速度显著加快,而且胚胎发育期抗温变能力有明显提高,孵化出苗率也有较大幅度增加。1989年5月,我们在上海嘉定县望新鱼苗场对团头鲂早期胚胎进行了中等规模(10公斤受精卵)电场刺激试验,取得了令人满意的后期结果。     

神经节苷脂对脑瘫大鼠大脑皮质区Nestin、NGF表达的影响

目的 观察神经节苷脂(GM1)对脑瘫大鼠大脑皮质区神经巢蛋白(Nestin)、神经生长因子(NGF)表达的影响,探讨GM1促进脑瘫神经修复的可能机制.方法 选择出生10周雄性SD大鼠200只,随机分为3组:假手术组60只,脑瘫模型140只,再分为模型组70只,腹腔注射生理盐水;GM1组70只,腹腔注射GM1.分别在术后0～24 h的7个时间点利用酶联免疫法检测大鼠大脑皮质区Nestin、NGF表达情况,并在实验前和后1～4 d观察大鼠的体质量变化情况.结果 (1)大鼠大脑皮质区Nestin表达GM1组0～24 h、模型组0～12 h明显高于假手术组(P＜0.01);GM1组16～24 h明显高于模型组(P＜0.01).(2)GM1组大鼠大脑皮质区NGF表达0～24 h明显高于模型组(P＜0.05)和假手术组(P＜0.01).模型组NGF表达仅0、4、8h高于假手术组(P＜0.05).(3)GM1组术后第1、2天体质量缓慢增加,至第3、4天明显高于模型组(P＜0.05),接近假手术组(P＞0.05),模型组体质量增加不明显.结论 预防性使用GM1是通过增强大脑皮质的Nestin和NGF表达并延长表达时间来发挥其对实验性脑瘫大鼠的神经保护作用.     

Relationship between rate of infection and markers of inflammation/immunity in Holy Birman cats with feline coronavirus

The aim of this study was to assess whether Holy Birman cats (HB) have a peculiar immune profile and a higher rate of infection by feline coronaviruses (FCoV). Leucocyte and lymphocyte subsets, antibody titers, α₁-acid glycoprotein (AGP), globulin fractions, IL-4, IL-12 and IFN-γ in blood and fecal FCoV excretion were determined in HB (n = 75) and in cats from other breeds (n = 94). Significantly higher CD4/CD8 ratio, IFN-γ concentration and IL12/IL4 ratio and significantly lower IL-4 concentration and proportion of shedders were found in HB than in other breeds. No other differences were found. In conclusion, this study did not provide evidence of peculiar immune profiles in HB, except for a prevalent Th1 profile, that may explain why in our caseload the rate of shedders was lower in HB than in other breeds.     

Infection dynamics of foot-and-mouth disease virus in pigs using two novel simulated-natural inoculation methods

In order to characterize foot-and-mouth disease virus (FMDV) infection dynamics in pigs, two simulated-natural inoculation systems were developed and evaluated. Intra-oropharyngeal (IOP) and intra-nasopharyngeal (INP) inoculation both enabled precise control of dose and timing of inoculation while simulating field exposure conditions.     

VH1-44 gene usage defines a subset of canine B-cell lymphomas associated with better patient survival

The use of specific immunoglobulin heavy chain variable region (VH) genes has been associated with increased patient survival in human B-cell lymphomas (hBCL). Given the similarity of human and canine BCL (cBCL) in morphology and clinical treatment, we examined the choice of VH in cBCL and determined whether VH gene selection was a distinct feature associated with survival time in dogs. VH gene selection and mutational status in 52 cBCL, including 29 diffuse large B-cell lymphomas (cDLBCL, the most common subtype of cBCL), were analyzed by comparison with the 80 published canine germline VH gene sequences. We further examined the prognostic impact of the subgroups defined by these features on canine survival. We found that VH1-44 was preferentially expressed in the majority of the 52 cBCLs (60%) as well as in the majority of the cDLBCL subset (59%). VH1-44 gene expression was associated with a statistically better overall survival (p = 0.039) in cBCL patients, as well as in the cDLBCL subset of patients (p = 0.038). These findings suggest that VH gene selection in cBCL is not random and may therefore have functional implications for cBCL lymphomagenesis, in addition to being a useful prognostic biomarker.     

Infection with foot-and-mouth disease virus (FMDV) induces a natural killer (NK) cell response in cattle that is lacking following vaccination

Natural killer (NK) cells play a role in innate antiviral immunity by directly lysing virus-infected cells and producing antiviral cytokines such as interferon gamma (IFN-γ). We developed a system for characterizing the bovine NK response to foot-and-mouth disease virus (FMDV), which causes a disease of cloven-hoofed animals and remains a threat to livestock industries throughout the world. IL-2 stimulation of PBMC resulted in poor killing of human K562 cells, which are often used as NK target cells, while lysis of the bovine BL3.1 cell line was readily detected. Depletion of NKp46-expressing cells revealed that 80% of the killing induced by IL-2 could be attributed to NKp46⁺ cells. In order to characterize the response of NK cells against FMDV in vivo, we infected groups of cattle with three different strains of the virus (A24 Cruzeiro, O1 Manisa, O Hong Kong) and evaluated the cytolytic ability of NK cells through the course of infection. We consistently observed a transient increase in cytolysis, although there was variation in magnitude and kinetics. This increase in cytolysis remained when CD3⁺ cells were removed from the preparation of lymphocytes, indicating that cytolysis was independent of MHC-T cell receptor interaction or γδ T cell activation. In contrast, animals monitored following vaccination against FMDV did not exhibit any increase in NK killing. These data suggest that NK cells play a role in the host immune response of cattle against FMDV, and contrast with the suppression of NK activity previously observed in swine infected with FMDV.