Immunological relatedness of human and porcine growth hormones.

The immunological relatedness of human and porcine growth hormones is examined by means of labelled human growth hormone and guinea pig antiserum. 1) Labelled human growth hormone is found in the precipitate after reaction with antiserum against porcine growth hormone. Parallel dilution curves are obtained with antisera against human and porcine growth hormones. 2) After addition of antiserum against porcine growth hormone, all the radioactivity is eluted from Sephadex G-100 with the void volume. 3) The addition of an excess of porcine hormone displaces labelled human growth hormone from antibodies against human growth hormone to the same extent as an excess of non-labelled human growth hormone does. 4) The standard radioimmunoprecipitation curves for porcine and human growth hormones obtained in the assay system for the human hormone are parallel in slope, provided that the human hormone and our preparation of the porcine hormone are introduced at a proportion of 1 to 560. 5) In a double diffusion test in agarose gel layers, with human and porcine growth hormones diffusing against guinea pig anti-porcine serum, cross reaction is observed. The conclusion is drawn that with guinea pig antisera, human and porcine growth hormones behave immunologically in a similar fashion. Labelled human growth hormone seems to have only such immunodeterminants as are also found in porcine growth hormone.     

大伏革菌防治小孔异担子菌的菌株筛选

以从芬兰引进的野生大伏革菌、中国的大伏革菌和小孔异担子菌为研究对象,通过平板对峙培养方法,从16株大伏革菌菌株中筛选出3株防治异担子菌的高效菌株,分别为:04052、08076和08077。这3号菌株具有较高的生长速率和拮抗率,能够快速覆盖病原菌,起到显著的生防效果。实验中还发现大伏革菌生长速率和拮抗率之间存在着显著的正相关关系。     

Enhancing Blockade of Plasmodium falciparum Erythrocyte Invasion: Assessing Combinations of Antibodies against PfRH5 and Other Merozoite Antigens

No vaccine has yet proven effective against the blood-stages of Plasmodium falciparum, which cause the symptoms and severe manifestations of malaria. We recently found that PfRH5, a P. falciparum-specific protein expressed in merozoites, is efficiently targeted by broadly-neutralizing, vaccine-induced antibodies. Here we show that antibodies against PfRH5 efficiently inhibit the in vitro growth of short-term-adapted parasite isolates from Cambodia, and that the EC₅₀ values of antigen-specific antibodies against PfRH5 are lower than those against PfAMA1. Since antibody responses elicited by multiple antigens are speculated to improve the efficacy of blood-stage vaccines, we conducted detailed assessments of parasite growth inhibition by antibodies against PfRH5 in combination with antibodies against seven other merozoite antigens. We found that antibodies against PfRH5 act synergistically with antibodies against certain other merozoite antigens, most notably with antibodies against other erythrocyte-binding antigens such as PfRH4, to inhibit the growth of a homologous P. falciparum clone. A combination of antibodies against PfRH4 and basigin, the erythrocyte receptor for PfRH5, also potently inhibited parasite growth. This methodology provides the first quantitative evidence that polyclonal vaccine-induced antibodies can act synergistically against P. falciparum antigens and should help to guide the rational development of future multi-antigen vaccines.     

Antifungal and fungicidal activities of tea extract and catechin against Trichophyton

We examined tea extract, (-) epigallocatechin gallate (EGCg) and theaflavin digallate (TF3) for their antifungal and fungicidal activities against Trichophyton mentagrophytes, T. rubrum, Candida albicans and Cryptococcus neoformans. Tea extract (2.5%) inhibited completely the growth of both T. mentagrophytes and T. rubrum. EGCg at 2.5 mg/ml failed to inhibit their growth, whereas TF3 at 0.5 mg/ml inhibited the growth. EGCg (1mg/ml) showed no fungicidal activity against Trichophyton. TF3 (1mg/ml) killed Trichophyton by a long time contact (72-96 hrs). Tea extract showed a fungicidal activity against Trichophyton in a dose- and contact time-dependent manner. It did not inhibit the growth of C. albicans, but at a high concentration, inhibited slightly the growth of C. neoformans. It had no fungicidal activity against C. albicans or C. neoformans.     

一株放线菌代谢产物除草活性的初步研究

从土壤中分离筛选出1株编号为Z40的链霉菌菌株,其代谢产物具有明显的除草活性。室内生物测定结果表明,Z40菌株发酵液干物质的除草活性主要表现为抑制生长作用。对反枝苋的主根和主茎生长抑制中浓度(EC50)分别为276.76 mg/L和1 609.37 mg/L,对狗尾草的主根和主茎生长抑制中浓度分别为501.81mg/L和629.01 mg/L。浓度为10 000 mg/L对油菜的萌发抑制率和主茎生长抑制率均为100.00%,而对小麦的生长发育没有明显影响。田间试验结果表明,Z40菌株代谢产物对稗、狗尾草、铁苋菜的防治效果均在80%以上,抑制率分别为80.30%,81.59%和88.71%。     

The effect of immunization against somatostatin on growth rates and growth hormone secretion in the chicken

The effect of both active passive immunization against somatostatin on growth rate and growth hormone levels was studied in chickens. Passive immunization against somatostatin by administration of antiserum had no effect on rate of growth of chickens and no persistent effect on circulating growth hormone (GH) levels. In acute experiments, administration of anti-somatostatin serum caused a marked elevation of GH levels in chickens at both 4 and 8 weeks of age, but the relative stimulation was greater in the older birds. Active immunization against somatostatin significantly stimulated growth rate in chickens, but was not shown to have a clear effect on circulating GH levels. These data suggest that somatostatin control over GH secretion may not be fully developed in the chicken at 4 weeks of age, but that immuno-neutralization of somatostatin can produce an increase rate of growth in chickens similar to that seen in mammals.     

内生细菌B10对稻瘟病菌抑制作用的初步研究

目的:研究内生细菌B10对水稻稻瘟病菌的抑制作用,为菌株的应用提供理论依据。方法:采用菌丝生长速率法、孢子萌发法和田间试验测定内生细菌发酵上清液和菌液对稻瘟病菌的抑制作用。结果:内生细菌B10发酵上清液对稻瘟病菌菌丝生长和孢子萌发有较强的抑制作用,100倍稀释液对菌丝生长的抑制率为79.37%,对孢子萌发的抑制率为63.42%,对稻瘟病的田间防治效果达70.2%以上。结论:内生细菌B10对稻瘟病有较强的抑菌作用。     

Evaluation of a xenogeneic VEGF vaccine in dogs with soft tissue sarcoma

Active immunization against pro-angiogenic growth factors or their receptors is an emerging strategy for controlling tumor growth and angiogenesis. Previous studies in rodent tumor models have indicated that immunization against xenogeneic growth factors is more likely to induce effective anti-tumor responses than immunization against the autologous growth factor. However, the effectiveness or safety of the xenogeneic vaccination approach has not been previously assessed in a clinically relevant outbred, spontaneous tumor model. Therefore, we investigated the safety and anti-tumor and anti-angiogenic effects of a xenogeneic vascular endothelial cell growth factor (VEGF) vaccine in pet dogs with spontaneous cancer. Nine dogs with soft tissue sarcoma were immunized with a recombinant human VEGF vaccine over a 16-week period. The effects of immunization on antibodies to human and canine VEGF, circulating VEGF concentrations, tumor microvessel density (MVD), and tumor growth were assessed. The xenogeneic VEGF vaccine was well-tolerated by all dogs and resulted in induction of humoral responses against both human and canine VEGF in animals that remained in the study long enough to receive multiple immunizations. Three of five multiply immunized dogs also experienced sustained decreases in circulating plasma VEGF concentrations and two dogs had a significant decrease in tumor MVD. The overall tumor response rate was 30% for all treated dogs in the study. We conclude therefore that a xenogeneic VEGF vaccine may be a safe and effective alternative means of controlling tumor growth and angiogenesis.     

Testing mechanistic models of growth in insects

Insects are typified by their small size, large numbers, impressive reproductive output and rapid growth. However, insect growth is not simply rapid; rather, insects follow a qualitatively distinct trajectory to many other animals. Here we present a mechanistic growth model for insects and show that increasing specific assimilation during the growth phase can explain the near-exponential growth trajectory of insects. The presented model is tested against growth data on 50 insects, and compared against other mechanistic growth models. Unlike the other mechanistic models, our growth model predicts energy reserves per biomass to increase with age, which implies a higher production efficiency and energy density of biomass in later instars. These predictions are tested against data compiled from the literature whereby it is confirmed that insects increase their production efficiency (by 24 percentage points) and energy density (by 4 J mg⁻¹) between hatching and the attainment of full size. The model suggests that insects achieve greater production efficiencies and enhanced growth rates by increasing specific assimilation and increasing energy reserves per biomass, which are less costly to maintain than structural biomass. Our findings illustrate how the explanatory and predictive power of mechanistic growth models comes from their grounding in underlying biological processes.     

Neurolin Ig Domain 2 Participates in Retinal Axon Guidance and Ig Domains 1 and 3 in Fasciculation

The optic disk–directed growth of retinal ganglion cell axons is markedly disturbed in the presence of polyclonal antineurolin antibodies, which mildly affect fasciculation (Ott, H., M. Bastmeyer, and C.A.O. Stuermer, 1998. J. Neurosci. 18:3363–3372).New monoclonal antibodies (mAbs) against goldfish neurolin, an immunoglobulin (Ig) superfamily cell adhesion/recognition molecule with five Ig domains, were generated to assign function (guidance versus fasciculation) to specific Ig domains. By their ability or failure to recognize Chinese hamster ovary cells expressing recombinant neurolin with deletions of defined Ig domains, mAbs were identified as being directed against Ig domains 1, 2, or 3, respectively. Repeated intraocular injections of a mAb against Ig domain 2 disturb the disk-directed growth: axons grow in aberrant routes and fail to reach the optic disk, but remain fasciculated. mAbs against Ig domains 1 and 3 disturb the formation of tight fascicles.mAb against Ig domain 2 significantly increases the incidence of growth cone departure from the disk-oriented fascicle track, while mAbs against Ig domains 1 and 3 do not. This was demonstrated by time-lapse videorecording of labeled growth cones.Thus, Ig domain 2 of neurolin is apparently essential for growth cone guidance towards the disk, presumably by being part of a receptor (or complex) for an axon guidance component.     

Properties of nerve growth factor from the venom of Bothrops atrox.

A glycoprotein fraction islated in poor yield (approx. 0.04%) from the venom of Bothrops atrox contained nerve growth factor. The material had biological activity, stability, the property of anomalous adsorption onto surfaces, apparent molecular weight and sub-unit structure that were similar to those for nerve growth factor that had been previously purified from the venom of Vipera russelli. Antiserum raised against nerve growth factor from Vipera russelli showed definite cross-reactivity with either the material from Bothrops atrox or a nerve growth factor-containing fraction from the venom of Ancistrodon piscivorus piscivorus, while antiserum against nerve growth factor from mouse had little effect on any of these preparations.     

Antimicrobial activity of Sesbania grandiflora flower polyphenol extracts on some pathogenic bacteria and growth stimulatory effect on the probiotic organism Lactobacillus acidophilus

Polyphenolic extracts (PE) of edible flower of Sesbania grandiflora were tested to evaluate its antimicrobial effect against some common pathogenic bacteria and growth promoting property against probiotic organism Lactobacillus acidophilus. The antimicrobial activity of S. grandiflora flower PE against selected pathogens was evaluated using both in vitro and in situ methods. In vitro studies suggested that PE has inhibitory effect against Staphylococcus aureus, Shigella flexneri 2a, Salmonella Typhi, Escherichia coli and Vibrio cholerae. The gram-positive organism S. aureus was the most sensitive organism to PE and minimum inhibitory concentration (MIC) was found to be 0.013 mg/mL where as the MIC of PE against V. cholerae was the highest (0.25 mg/mL). On the other hand PE showed growth promoting effect on the common probiotic bacterium L. acidophilus. The major finding was that S. grandiflora PE induced a significant biomass increase of L. acidophilus grown in liquid culture media. PE showed reduction of S. aureus growth in food (fish) during storage at 10°C. High performance liquid chromatography analysis showed that rutin, a major flavonoid of the PE diminished in the culture medium MRS broth with the growth of L. acidophilus.     

The enemy release and EICA hypothesis revisited: incorporating the fundamental difference between specialist and generalist herbivores

The success of invasive plants has been attributed to their escape from natural enemies and subsequent evolutionary change in allocation from defence to growth and reproduction. In common garden experiments with Senecio jacobaea, a noxious invasive weed almost worldwide, the invasive populations from North America, Australia, and New Zealand did indeed allocate more resources to vegetative and reproductive biomass. However, invasive plants did not show a complete change in allocation from defence to growth and reproduction. Protection against generalist herbivores increased in invasive populations and pyrrolizidine alkaloids, their main anti‐herbivore compounds, did not decline in invasive populations but were higher overall compared with native populations. In contrast, invasive plants lost additional protection against specialist herbivores adapted to pyrrolizidine alkaloids. Hence, the absence of specialist herbivores in invasive populations resulted in the evolution of lower protection against specialists and increased growth and reproduction, but also allowed a shift towards higher protection against generalist herbivores.     

Life‐history constraints in grassland plant species: a growth‐defence trade‐off is the norm

Plant growth can be limited by resource acquisition and defence against consumers, leading to contrasting trade‐off possibilities. The competition‐defence hypothesis posits a trade‐off between competitive ability and defence against enemies (e.g. herbivores and pathogens). The growth‐defence hypothesis suggests that strong competitors for nutrients are also defended against enemies, at a cost to growth rate. We tested these hypotheses using observations of 706 plant populations of over 500 species before and following identical fertilisation and fencing treatments at 39 grassland sites worldwide. Strong positive covariance in species responses to both treatments provided support for a growth‐defence trade‐off: populations that increased with the removal of nutrient limitation (poor competitors) also increased following removal of consumers. This result held globally across 4 years within plant life‐history groups and within the majority of individual sites. Thus, a growth‐defence trade‐off appears to be the norm, and mechanisms maintaining grassland biodiversity may operate within this constraint.     

Synthetic peptide approach to the analysis of kinase activities of avian EGF receptor and v-erbB protein

Analysis of the structure and function of a protein such as the epidermal growth factor receptor is facilitated by the use of antibodies directed against discrete portions of the protein. Here, we describe the characterization and use of antibodies directed against synthetic peptides corresponding to specific portions of the epidermal growth factor receptor and/or v-erbB protein. In particular, one useful antiserum has allowed us to compare the protein kinase activities of the epidermal growth factor receptor and the v-erbB proteins and to conclude that the v-erbB protein is a protein-tyrosine specific kinase as is its homologue the avian epidermal growth factor receptor.     

A two-strain mixture of rhizobacteria elicits induction of systemic resistance against Pseudomonas syringae and Cucumber mosaic virus coupled to promotion of plant growth on Arabidopsis thaliana

We evaluated a commercial biopreparation of plant growth-promoting rhizobacteria (PGPR) strains Bacillus subtilis GB03 and B. amyloliquefaciens IN937a formulated with the carrier chitosan (BioYield) for its capacity to elicit growth promotion and induced systemic resistance against infection by Cucumber Mosaic Virus (CMV) and Pseudomonas syringae pv. tomato DC3000 in Arabidopsis thaliana. The biopreparation promoted plant growth of Arabidopsis hormonal mutants, which included auxin, gibberellic acid, ethylene, jasmonate, salicylic acid, and brassinosteroid insensitive lines as well as each wild-type. The biopreparation protected plants against CMV based on disease severity in wild-type plants. However, virus titre was not lower in control plants and those treated with biopreparation, suggesting that the biopreparation induced tolerance rather than resistance against CMV. Interestingly, the biopreparation induced resistance against CMV in NahG plants, as evidenced by both reduced disease severity and virus titer. The biopreparation also elicited induced resistance against P. syringae pv. tomato in the wild-type but not in NahG transgenic plants, which degrade endogenous salicylic acid, indicating the involvement of salicylic acid signaling. Our results indicate that some PGPR strains can elicit plant growth promotion by mechanisms that are different from known hormonal signaling pathways. In addition, the mechanism for elicitation of induced resistance by PGPR may be pathogen-dependent. Collectively, the two-Bacilli strain mixture can be utilized as a biological inoculant for both protection of plant against bacterial and viral pathogens and enhancement of plant growth.     

Studies on the role of basic fibroblast growth factor in vivo: inability of neutralizing antibodies to block tumor growth

Affinity-purified polyclonal rabbit antibodies prepared against recombinant basic fibroblast growth factor (bFGF) neutralized the ability of bFGF to stimulate plasminogen activator (PA) production and endothelial cell migration in vitro. After iodination and intraperitoneal injection of the antibodies in mice, approximately 76% of the maximum circulating level of 125I-anti-bFGF antibodies (AF) was found as intact IgG after 24 hr. Furthermore, the circulating 125I-AF retained the ability to bind bFGF. Studies were performed to determine whether the growth of three different murine tumors (CT26, EHS, or B16/BL6) could be inhibited with affinity-purified neutralizing antibodies against bFGF. Tumors were injected subcutaneously in syngeneic mice, and neutralizing antibodies against bFGF were injected daily into the peritoneum. All studies, which varied in tumor burden, antibody dose, and study length, indicated that neutralizing antibodies against bFGF had no effect on tumor size, tumor growth, or tumor histology.     

Fumiquinones A and B, nematicidal quinones produced by Aspergillus fumigatus

New nematicides named fumiquinones A (1) and B (2), together with spinulosin (3), LL-S490beta (4), and pseurotin A (5), were isolated from Aspergillus fumigatus and their structures were established by spectroscopic methods including 2D-NMR. Compound 1 showed effective nematicidal activities against Bursaphelenchus xylophilus and Pratylenchus penetrans without inhibiting plant growth except for lettuce seedlings. Compound 2 showed effective nematicidal activity against B. xylophilus, but had no inhibitory activity against P. penetrans. Compounds 3-5 showed effective nematicidal activities against B. xylophilus without any plant growth inhibition. Compounds 1-5 had no nematicidal activity against Caenorhabditis elegans. This is the first report of the nematicidal activities of compounds 3-5.     

Immunization of rats and sheep against granulosa cell-inhibitory factor from bovine follicular fluid increases the number of large follicles in rats and the ovulation rate in sheep.

Granulosa cell-inhibitory factor (GCIF), a low molecular weight factor from bovine follicular fluid, inhibits the proliferation of bovine granulosa cells in vitro and the growth of large follicles in rats in vivo. In this study the effects of (1) immunization of rats against GCIF on follicular growth and (2) immunization of sheep against GCIF on ovulation rate were studied. The ability of antiserum from sheep immunized against GCIF to reduce the inhibitory effect of GCIF on bovine granulosa cell proliferation in culture was also examined. Immunization of rats against GCIF increased the number of large follicles (P < 0.001) but decreased the number of small follicles (P < 0.05) per ovary. Ovarian mass (P < 0.05) and uterine wet (P < 0.05) and dry (P < 0.01) masses were increased in immunized rats. Immunization of sheep against GCIF, followed by boosting over two breeding seasons, increased ovulation rate (P < 0.01). Addition of antiserum from sheep immunized against GCIF reduced or abolished the inhibitory effect of GCIF on granulosa cell proliferation (P < 0.01). These data provide further evidence that GCIF has an important role in controlling follicle growth and ovulation in vivo.     

茅苍术挥发油对三种内生真菌及七种外源真菌的抑菌活性

为了研究宿主植物次级代谢产物对内生真菌生长的抑制作用,以药用植物茅苍术及其内生真菌为材料,采用有机溶剂萃取法提取茅苍术挥发油,应用滤纸片扩散法和平板涂布法研究茅苍术挥发油对茅苍术内生真菌及其他外源真菌的抑菌作用.结果表明: 挥发油对3种内生真菌生长具有抑制作用;对酵母、水霉有很强的抑菌活性;对根霉、犁头霉抑菌作用不明显;对绿色木霉、黑曲霉的产孢具有抑制作用;对疫霉生长无抑制作用.在高浓度挥发油胁迫下,内生真菌菌丝分支增多,分支间距离变短,气生菌丝生长受到抑制.两种内生真菌对挥发油具有代谢转化能力,降低了其主要成分的含量.表明茅苍术挥发油对内生真菌生长具有限制作用,但内生真菌能够通过自身分解代谢适应茅苍术挥发油.