Sexual hybridization of Lycopersicon esculentum and Solanum rickii by means of a sesquidiploid bridging hybrid

A sesquidiploid hybrid having two genomes of Lycopersicon esculentum and one of Solanum lycopersicoides served as a pistillate bridging parent in crosses with Solanum rickii to produce L. esculentum x S. rickii hybrid progeny. Of the four progeny obtained, one (GH2754) was diploid and three were aneuploid with extra S. lycopersicoides chromosomes. The hybrids had morphological features of both parents, but attributes of the wild parent dominated. The hybrid nature of the four progeny was confirmed by isozyme, restriction fragment length polymorphism, and cytological analyses. A mean of 9.15 bivalents was observed in pollen mother cells of GH2754. A high level of pollen abortion was seen in all hybrids. Crosses of the hybrids with staminate S. rickii yielded one backcross individual, revealing a very low, but certain level of female fertility. Colchicine treatment of GH2754 generated one promising amphidiploid hybrid, which exhibited strong preferential chromosome pairing (94% of the examined cells had 24 bivalents) and appreciable pollen fertility (43% stainable). Chromosome pairing, isozyme, and restriction fragment length polymorphism data support a very close relationship between the two Solanum spp. and a much greater distance between them and L. esculentum, but the data do not discriminate between them in respect to their distances from the latter. The cytological and molecular observations, previous reports of successful transfer of traits from S. lycopersicoides to L. esculentum, and our hybridization of L. esculentum x S. rickii suggest good prospects for gene transfer from S. rickii to L. esculentum.     

黄果茄杀灭钉螺有效成分的分离提纯及其效果观察

目的分离提纯黄果茄果实灭螺的有效成分,观察灭螺效果,并确定其分子结构。方法将黄果茄果实去蒂去籽后干燥粉碎,用95%乙醇提取并浓缩,然后加乙酸乙酯处理,用薄层层析法(TLC)和柱层析法(CCL)对其进行分离,得到7种主要组份。采用“浸泡法”对其中4种含量较高的组分进行灭钉螺实验,确证Rf=0.58这一生物碱组分(A)为主要灭螺成分之一。选择最佳洗脱剂对灭螺效果最好组分A进行分离,得到A1及A2两组分。对A1,A2进行灭钉螺实验,比较其灭螺效果。电子轰击质谱测定有效成分分子量、核磁共振仪和红外光谱仪测定分子结构。结果黄果茄果实有效成分A(Rf=0.58)的灭螺效果较好,当投药量为2.50 mg/L,钉螺的死亡率为94.2%(28℃)。乙酸乙酯-氯仿-甲醇(11∶11∶35)系统对A的分离效果最好。灭螺对照实验发现:当A2投药量为0.20 mg/L,钉螺的死亡率为100.0%(28℃),其分子量为867,熔点为298～305℃。结论黄果茄有效成分提纯物A2为边缘茄碱(-αsolamarrgine),其对湖北钉螺有很好的杀灭效果。     

One-step generation of cytoplasmic male sterility by fusion of mitochondrial-inactivated tomato protoplasts with nuclear-inactivated Solanum protoplasts

Mesophyll protoplasts of Lycopersicon esculentum were treated with iodoacetamide to inactivate mitochondria, and protoplasts of Solanum acaule and Solanum tuberosum were irradiated with gamma- or x-rays to inactivate nuclei. Mixtures of protoplasts thus modified were treated with Ca2+ and polyethylene glycol to obtain heterologous fusion products. Among the fusion products were some tomato plants that were indistinguishable from the original cultivars with respect to morphology, physiology, and chromosome number (2N = 24) but exhibited various degrees of male sterility (MS): complete lack or malformation of anthers, shrunken pollen, and normal-looking stainable pollen that could not germinate. The MS thus induced in five cultivars of different growth types, including one of subspecies L. esculentum cerasiforme, was inherited maternally over several generations and is, therefore, cytoplasmically determined MS (CMS). Analysis of mitochondrial DNA revealed that the mitochondrial genome of the CMS hybrids does not contain all elements of the mitochondrial DNA of either parent but includes sequences of a recombinational nature not present in either parent. The CMS hybrids, therefore, possess a true hybrid mitochondrial genome. The same procedure applied to fusion of tomato with Solanum lycopersicoides and Nicotiana tabacum cells did not produce CMS phenotypes. The advantages of this method over others for generating MS are as follows: (i) only one step is required; (ii) the nuclear genotype of the cultivar is unaffected; (iii) the prospect that cytoplasmic determination allows generation of 100% CMS progenies. The normal-appearing but nonfunctional pollen of certain CMS types might render them attractive to pollinating bumblebees that thus would facilitate production of hybrid seed.     

Molecular mechanisms of apoptosis in hepatocellular carcinoma cells induced by ethanol extracts of Solanum lyratum Thumb through the mitochondrial pathway

AIM To explore the induction effects and mechanism of Solanum lyratum Thumb(ST) on human hepatocellularcarcinoma SMMC-7721 cells through the mitochondrial pathway.METHODS The experiments were conducted on three groups: an experimental group (with ST ethanol extracts' concentration being 2.5, 5 and 10 mg/L), a negative control group (with only nutrient solution, 0 mg/L ST ethanol extracts), and a positive control group (2.5 mg/L DDP). The inhibition rate of cell proliferation was checked by using the methyl thiazolyl tetrazolium method, and cell apoptosis was tested by TUNEL method. Furthermore, RT-PCR was used to examine m RNA expression of Fas, Fas L, caspase-8, caspase-3, p53 and Bcl-2 genes.RESULTS Compared with the negative control group, the inhibition and apoptosis rates of the experimental group with different concentrations of ST extracts on human hepatocellular carcinoma SMMC-7721 cells significantly increased(P0.05). Besides, the m RNA expression of Fas L and Bcl-2 significantly decreased(P0.05) while the m RNA expression of Fas, caspase-8, caspase-3 and p53 increased significantly. When compared with the positive control group, the experimental groups with 5 mg/L ST ethanol extracts showed effects similar to the positive control group.CONCLUSION ST ethanol extracts induced the apoptosis of hepatocellular carcinoma SMMC-7721 cells through up-regulated Fas, caspase-8, caspse-3 and p53, and down-regulated Fas L and Bcl-2 in the mitochondrial pathway.     

Transfer of allogeneic CD62L- memory T cells without graft-versus-host disease

The major challenge in allogeneic hematopoietic cell transplantation is how to transfer allogeneic T-cell immunity without causing graft-versus-host disease (GVHD). Here we report a novel strategy to selectively prevent GVHD by depleting CD62L(+) T cells (naive and a subset of memory T cells). In unprimed mice, CD62L(-) T cells (a subset of memory T cells) failed to proliferate in response to alloantigens (which the mice have never previously encountered) and were unable to induce GVHD in allogeneic hosts. CD62L(-) T cells contributed to T-cell reconstitution by peripheral expansion as well as by promoting T-cell regeneration from bone marrow stem/progenitor cells. CD62L(-) T cells from the animals previously primed with a tumor cell line (BCL1) were able to inhibit the tumor growth in vivo but were unable to induce GVHD in the third-party recipients. This novel technology may allow transfer of allogeneic recall antitumor and antimicrobial immunity without causing GVHD.     

Selective expression of IL-7 receptor on memory T cells identifies early CD40L-dependent generation of distinct CD8+ memory T cell subsets

Several recent studies have demonstrated that T-helper cell-dependent events during the initial priming period are required for the generation of CD8(+) T cell-mediated protective immunity. The underlying mechanisms of this phenomenon have not yet been determined, mostly because of difficulties in studying memory T cells or their precursor populations at early stages during immune responses. We identified IL-7 receptor (CD127) surface expression as a marker for long-living memory T cells, most importantly allowing the distinction between memory and effector T cells early after in vivo priming. The combination of surface staining for CD127 and CD62L further separates between two functionally distinct memory cell subsets, which are similar (if not identical) to cell subsets recently described as central memory T cells (CD127(high) and CD62L(high)) and peripheral effector memory T cells (CD127(high) and CD62L(low)). Using this new tool of memory T cell analysis, we demonstrate that CD8(+) T cell priming in the absence of T cell help or CD40L specifically alters the generation of the effector memory T cell subset, which appears to be crucial for immediate memory responses and long-term maintenance of effective protective immunity. Our data reveal a unique strategy to obtain information about the quality of long-term protective immunity early during an immune response, a finding that may be applied in a variety of clinical settings, including the rapid monitoring of vaccination success.     

黄果茄植物提取物的灭螺效果及对鱼类和大鼠急性毒性试验研究

目的 掌握和了解黄果茄植物提取物（SX）对钉螺的杀灭效果和对鱼类以及大鼠的急性毒性作用。方法 进行了常规的灭螺试验和鱼类急性毒性试验以及大鼠急性经口毒性试验。结果 SX浓度为4．32mg/L时浸泡湖北钉螺,24h死亡率为96．7％,48h死亡率达100％;SX对鱼类稀有Ju鲫的急性毒性试验,在0．27mg/L浓度中,24h的死亡率为0,在17＝28mg/L浓度中,24h死亡率为100％;SX对稀有Ju鲫的LC50为2．02mg/L,95%的可信限为1．33－3．06mg/L。对大鼠急性经口毒性的绝对致死剂量为2150mg/kg体重,LD50为794mg/kg体重,95％可信限为584－1080mg/kg体重。结论 SX具有较好的灭螺效果,但对鱼类稀有Ju鲫有中等毒性作用,对大鼠的作用属低毒类。     

Modulation of the expression of long-term cardiac memory by short-term cardiac memory in patients with Wolff-Parkinson-White syndrome after catheter ablation.

BACKGROUND: The interaction between long-and short-term cardiac memory (CM) is unknown. METHODS AND RESULTS: The T-wave areas and QTc intervals in each ECG lead were analyzed in 11 patients with manifest Wolff-Parkinson-White syndrome with posterior or septal accessory pathway (4 females; mean age: 47+/-12 years) in the following ECGs: (1) immediately after catheter ablation (post-ablation ECG); (2) immediately after 20 min of right ventricular outlet pacing (post-pacing ECG); and (3) 1 week after ablation (recovery ECG). Compared with the post-ablation ECGs, the T-wave areas of the recovery ECGs in leads II and aV(F) changed dramatically from negative to positive while that in lead III became less negative (p<0.01), and those in leads I, aV(L), and V(2-4) became less positive (p<0.05). Compared with the post-ablation ECGs, the T-wave areas of the post-pacing ECGs in leads III and aV(F) became less negative (p<0.01), and those in leads I, aV(L), and V(2-4) became less positive (p<0.05). The QTc interval in the post-ablation ECG was significantly longer than in either the post-pacing or recovery ECGs (p<0.05). CONCLUSIONS: Mechanisms involved in the expression of long-term CM could be affected by short-term CM.     

慢性氟中毒大鼠脑组织氧化应激水平及学习记忆功能的变化

目的 观察慢性氟中毒大鼠脑组织及血浆氧化应激水平的改变,探讨氟中毒性神经损害发病机制中氧化应激水平与学习记忆的关系.方法 SD大鼠按体质量随机分为3组,每组8只.对照组:自由饮用自来水,自来水含氟量低于0.5 mg/L;低剂量染氟组:饮水含氟量为5 mg/L;高剂量染氟组:饮水含氟量为50ms/L.实验期为6个月.检测大鼠学习记忆功能、血浆和脑组织总抗氧化能力(T-AOC)及丙二醛(MDA)水平.结果 高剂量染氟组大鼠逃避潜伏期[(14.37±3.48)s]长于对照组[(5.84±1.87)s]和低剂量染氟组[(7.18±1.42)s],两组间比较差异有统计学意义(P<0.05);高剂量染氟组、低剂量染氟组大鼠血浆和脑组织T-AOC水平[(1.37±0.27)×103 U/L、(0.24±0.06)×103 U/g Pr,(1.20±0.14)×103 U/L、(0.41±0.10)×103 U/g Pr]低于对照组[(2.17±0.11)×103 U/L,(0.79±0.11)×103 U/g Pr],两组间比较差异有统计学意义(P<0.05);高剂量染氟组大鼠血浆和脑组织MDA水平[(3.72±0.59)mmol/L、(4.01±0.21)mmol/g Pr]显著高于对照组[(2.34±0.16)nunol/L、(2.97±0.11)mmol/g Pr]和低剂量染氟组[(2.68±0.33)mmol/L、(3.38±0.21)mmol/g Pr],两组间比较差异有统计学意义(P<0.05).结论 慢性氟中毒可使机体氧化应激水平升高,大鼠学习记忆能力减退可能与氧化应激水平的升高有关.     

Severe chronic graft-versus-host disease is characterized by a preponderance of CD4(+) effector memory cells relative to central memory cells

Donor alloreactive CD4(+) T cells are important to the pathogenesis of chronic graft-versus-host disease (cGVHD), but specific subsets of CD4(+) T cells responsible for GVHD have not been defined. We hypothesized that cGVHD might be associated with a preponderance of CD4(+) effector memory cells (CCR7(-)/CD62L(low), CD4(EM)). We analyzed CCR7 and CD62L expression on CD4(+) T cells from stem cell transplantation patients, who did or did not develop cGVHD, and healthy donors. Patients with cGVHD had a higher percentage of CD4(EM) cells (35.5% +/- 2.9%) than healthy donors (13.8% +/- 0.7%; P <.0001) or patients without cGVHD that received a transplant (21.7% +/- 2.1%; P <.01). Using corticosteroid dose as a surrogate marker for cGVHD severity, severe cGVHD was associated with a higher percentage of CD4(EM) cells. The proportion of CD4(EM) cells in corticosteroid-dependent patients with systemic lupus erythematosis or Wegener granulomatosis did not differ from patients without cGVHD that received a transplant. This finding implies that overrepresentation of CD4(EM) cells is a unique feature of cGVHD.     

Lectins and toxins in the plant diet of Phlebotomus papatasi (Diptera: Psychodidae) can kill Leishmania major promastigotes in the sandfly and in culture

Leishmania major promastigotes are agglutinated and die in their vector, Phlebotomus papatasi, after the sandflies feed on some plants that are found in their natural habitat. In in-vitro assays, extracts of Ricinus communis (Euphorbiaceae), Capparis spinosa (Capparaceae), Prosopis farcta (Mimosaceae) and Tamarix nilotica (Tamaricaceae) agglutinated and killed the parasites. This activity could be inhibited by specific carbohydrates, indicating that it was the result of various lectins in the extracts. An extract of Solanum luteum (Solanaceae) lysed the promastigotes under similar conditions and this cytotoxicity was not abated by the sugars tested. High mortality of promastigotes occurred in infected flies after they ingested an extract of R. communis, even when the extract fed to the flies had been pre-mixed with glucose, a carbohydrate that inhibited the agglutination caused by such an extract in vitro. The results indicate that the lectins and toxins found in the vegetation in L. major foci may decrease the transmission of the parasite.     

Early establishment of diverse T cell receptor profiles for influenza-specific CD8(+)CD62L(hi) memory T cells

Single-cell analysis of endogenous, primary CD8(+) T cell responses to the influenza D(b)NP(366) and D(b)PA(224) epitopes indicates that prominent clonotypes bearing "public" or "shared" T cell receptors (TCRs) subset early into CD62L(hi) and CD62L(lo) populations. The CD62L(lo) effectors divide more and are rapidly eliminated during the contraction phase, whereas stable CD62L(hi) memory populations persist in the long-term. Reflecting the high frequency of small CD62L(hi) clones expressing "private" TCRs, the TCR diversity range per mouse is generally two times higher within the CD62L(hi)CD8(+)D(b)NP(366)(+) set (1.6 times higher for CD62L(hi)CD8(+)D(b)PA(224)(+)) from 8 to >180 days after antigen challenge. Memory CD8(+)CD62L(hi) T cell precursors thus segregate from the outset into populations expressing "best-fit" and "suboptimal" TCR characteristics, with this pattern being maintained stably thereafter. Hence, our analysis suggests that early establishment of influenza-specific memory within the CD8(+)CD62L(hi) subset preserves clonal diversity and prevents "overdominance" by a few public, or shared, clones.     

Study of apoptosis in human liver cancers

AIM: To investigate the action of apoptosis in occurrence of liver carcinomas in vivo and the biological effect of Solanum lyratum Thumb on BEL-7404 cell line inducing apoptosis in vivo. METHODS: The apoptosis in the liver carcinoma was detected with terminal deoxynucl neotidyl transferase mediated dUTP nick end labelling (TUNEL); the cancer cells cultured in DMED medium were treated with extract of Solanum lyratum Thumb and observed under microscope, and their DNA was assayed by gel electrophoresis. RESULTS: In vivo apoptotic cells in the cancer adjacent tissues inceased; in vivo treatment of liver cancers with extract of Solanum lyratum Thumb could induce the cells to manifest a typical apoptotic morphology. Their DNA was fractured and a characteristic ladder pattern could be found using electrophoresis. CONCLUSION: In vivo the apoptosis of carcinomas was lower; maybe the cells divided quickly and then the cancers occurred. In the cancer adjacent tissues,the apoptosis pricked up, and in vivo Solanum lyratum Thumb could induce the apoptosis of BEL-7404 cells.     

CD62L- memory T cells enhance T-cell regeneration after allogeneic stem cell transplantation by eliminating host resistance in mice

A major challenge in allogeneic hematopoietic cell transplantation is how to transfer T-cell immunity without causing graft-versus-host disease (GVHD). Effector memory T cells (CD62L(-)) are a cell subset that can potentially address this challenge because they do not induce GVHD. Here, we investigated how CD62L(-) T cells contributed to phenotypic and functional T-cell reconstitution after transplantation. On transfer into allogeneic recipients, CD62L(-) T cells were activated and expressed multiple cytokines and cytotoxic molecules. CD62L(-) T cells were able to deplete host radioresistant T cells and facilitate hematopoietic engraftment, resulting in enhanced de novo T-cell regeneration. Enhanced functional immune reconstitution was demonstrated in CD62L(-) T-cell recipients using a tumor and an influenza virus challenge model. Even though CD62L(-) T cells are able to respond to alloantigens and deplete host radioresistant immune cells in GVHD recipients, alloreactive CD62L(-) T cells lost the reactivity over time and were eventually tolerant to alloantigens as a result of prolonged antigen exposure, suggesting a mechanism by which CD62L(-) T cells were able to eliminate host resistance without causing GVHD. These data further highlight the unique characteristics of CD62L(-) T cells and their potential applications in clinical hematopoietic cell transplantation.     

Dissecting memory T cell responses to TB: Concerns using adoptive transfer into immunodeficient mice

Several studies have used adoptive transfer of purified T cell subsets into immunodeficient mice to determine the subset of T cells responsible for mediating protection against Mycobacterium tuberculosis. These studies suggested that CD62L(hi) memory CD4(+) T cells from BCG-vaccinated mice are key for protection against tuberculosis. Importantly, we observed that transfer of na?ve CD4(+) T cells into Rag1-/- recipients protected against a mycobacterial challenge as well as transfer of BCG-experienced CD4(+) T cells. We found that transfer of total CD4(+) T cells from na?ve mice or enriched CD62L(hi)CD4(+) T cells from BCG-vaccinated mice into Rag1-/- recipients induced severe colitis by 3 weeks post cell transfer, whereas transfer of CD62L(lo)CD4(+) T cells from BCG-vaccinated mice did not. Na?ve and CD62L(hi)CD4(+) T cells proliferated extensively upon transfer and developed an activated effector phenotype in the lung, even in the absence of infectious challenge. The induction of colitis and systemic cytokine response induced by the transfer and subsequent activation of CD4(+) T cells from na?ve mice or CD62L(hi)CD4(+) T cells from BCG-vaccinated mice, into immunodeficient recipients, may heighten their ability to protect against mycobacterial challenge. This raises doubts about the validity of this model to study CD4(+) T cell-mediated protection against tuberculosis.     

氟对大鼠胆碱酯酶活性和学习记忆功能的影响

目的 研究氟对慢性氟中毒大鼠学习、记忆功能的影响以及其可能的机制,探讨氟对脑组织胆碱酯酶活性的影响多氟中毒大鼠智力损伤程度的关系.方法 SD大鼠按性别和体质量随机分为3组,对照组:自由饮用自来水,含氟量低于1mg/L;低剂量染氟组:饮水含氟量为5mg/L;高剂量染氟组:饮水含氟量为50mg/L.实验3个月时检测大鼠行为学变化和脑组织胆碱酯酶活性.结果 高剂量染氟组大鼠的逃避潜伏期时间[(17.55±1.51)s]长于对照组[(12.07±0.97)s],两组比较差异有统计学意义(P＜0.05);高剂量染氟组探索实验目标次数[(2.88±0.35)次]与对照组[(4.00±0.50)次]比较,有降低趋势,但差异无统计学意义(P＞0.05);高剂量染氟组的乙酰胆碱酯酶和丁酰胆碱酯酶活性[(1.41±0.19)、(0.49±0.07)kU/g]均低于对照组[(1.88±0.13)、(1.04±0.16)kU/g)],差异均有统计学意义(P＜0.05).结论 过量氟在体内蓄积可使大鼠智力降低,脑内的胆碱酯酶活性降低可能是其机制之一.     

Profiling of melatonin in the model tomato (Solanum lycopersicum L.) cultivar Micro-Tom

Abstract:  Melatonin exists in a considerable variety of plant species. However, the physiological roles of melatonin in plants are not well understood. In this study, the distribution and accumulation of melatonin during leaf and fruit development were analyzed in Micro-Tom, a model cultivar of tomato ( Solanum lycopersicum L.). Melatonin was extracted using an acetone–methanol method and measured by enzyme-linked immunosorbent assay. Melatonin was detected in leaves, stems, roots, flowers, fruits, seedlings and seeds in the range of 1.5–66.6 ng/g fresh weight, with seeds containing the highest concentration of melatonin. In fruits and leaves, melatonin concentrations varied depending on the developmental stage, suggesting that melatonin controls some of the processes involved in plant maturation.     

载脂蛋白基因与空间记忆力及胆固醇代谢的相关性分析

目的 研究载脂蛋白E(apoE)基因在早老痴呆疾病中的作用.方法 选取C57BL/6J鼠,通过显微注射法建立人突变apoE4近交系转基因鼠,PCR初筛,再将首建鼠与正常C57BL/6J鼠繁育,将获得的6只转基因鼠作为转基因组,经Southern杂交鉴定,同时出生的结果为阴性的6只小鼠作为对照组,用酶法测定2组小鼠2、9...     

Promiscuous peptide of 16 kDa antigen linked to Pam2Cys protects against Mycobacterium tuberculosis by evoking enduring memory T-cell response

One of the main reasons considered for BCG failure in tuberculosis-endemic areas is impediment by environmental mycobacteria in its processing and generation of memory T-cell response. To overcome this problem, we developed a unique lipopeptide (L91) by linking the promiscuous peptide (sequence 91-110) of 16 kDa antigen of Mycobacterium tuberculosis to Pam2Cys. L91 does not require extensive antigen processing and generates enduring Th1 memory response. This is evidenced by the fact that L91 significantly improved the activation, proliferation, and generation of protective T cells. Furthermore, L91 surmounts the barrier of major histocompatibility complex polymorphism and induces better protection than BCG. This peptide has self-adjuvanting properties and activates dendritic cells. Importantly, L91 activates T cells isolated from purified protein derivative-positive healthy volunteers that responded weakly to free peptide (F91). In essence, L91 can be a potent future vaccine candidate against tuberculosis.     

Sand fly feeding on noxious plants: a potential method for the control of leishmaniasis.

The sand fly Phlebotomus papatasi transmits Leishmania major, which causes cutaneous leishmaniasis, in vast regions of the Old World. In addition to blood, the sand flies feed on plants. In a study of this diet, we observed that one night of feeding on branches of Solanum jasminoides, Ricinus communis, or Bougainvillea glabra drastically shortened the life span of the sand flies. Flowering B. glabra attracted P. papatasi in the field. Nevertheless, in the region endemic for L. major in yards abounding with vector sand flies, the number of P. papatasi trapped near hedges of B. glabra was eight times less (62 versus 502 flies trapped) than in the control sites. The results imply that B. glabra affords local protection against sand fly bites and decreases the risk of leishmaniasis. We suggest that this and other ornamental plants that are harmful to sand flies can be used as a tool for this purpose.