peinamine, a new bisbenzylisoquinoline alkaloid from arrow tips (pei-namô) of the upper orinoco.a new bisbenzylisoquinoline alkaloid has been isolated from a curare of the upper orinoco region. the curare is made by indians from an unknown plant (probably menispermacea) and is kept on arrow tips. the structure of the alkaloid, named peinamine, has been elucidated on the basis of its chemical reactions and spectroscopic data (n.m.r., m.s. and o.r.d.).197720330
fecal steroids in diarrhea. i. acute shigellosis.fecal bile acid and neutral sterol patterns of five healthy adult male volunteers, who were challenged by a virulent shigella flexneri 2a (m42-43) strain and developed dysentery were studied. it was observed that cholic acid was increased from 1.9 +/- 0.4% of total bile acid in the feces before infection to 14.5 +/- 2.1% during diarrhea (p less than 0.001). chenodeoxycholic acid also was increased from 3.2 +/- 0.7 to 8.7 +/- 3.2% in diarrhea but the difference was not significant statistically. ...1976786002
rhizobial lipo-oligosaccharides: answers and questions.rhizobium bacteria produce certain lipo-oligosaccharides (modified chitin oligomers) after induction of nodulation (nod) gene transcription by the host plant. the function of the rhizobial nod genes in the biosynthesis of these lipo-oligosaccharides, focusing on their host specific aspects, is discussed. the lipo-oligosaccharides can elicit various responses in the host plants, like the formation of pre-infection threads and nodule meristems. speculating on their function in plant morphogenesis ...19921463833
effect of an unknown plant substance on a shield bug. 19725049196
[chronic maxillofacial suppuration due to unknown plant foreign bodies. apropos of 2 cases with ct scanning].common features in two patients with chronic suppurative lesions of the maxillofacial region from vegetable foreign bodies were : foreign body origin of the accident ; chronic nature of the suppuration (7 and 23 months respectively) ; multiple operations by different surgical teams ; radiotransparency of the foreign bodies. positive signs on ct scanning can confirm the diagnosis, but cannot exclude it when normal images are obtained. the number and localization of wood fragments may limit the va ...19846377462
sequence variations in alleles of the avirulence gene avrpphe.r2 from pseudomonas syringae pv. phaseolicola lead to loss of recognition of the avrpphe protein within bean cells and a gain in cultivar-specific virulence.the bean halo blight pathogen, pseudomonas syringae pv. phaseolicola (psph), is differentiated into nine races based on the presence or absence of five avirulence (avr) genes in the bacterium, which interact with corresponding resistance genes. r1-r5, in phaseolus vulgaris. the resistance gene r2 is matched by avrpphe, which is located adjacent to the cluster of hrp genes that are required for pathogenicity of psph. although only races 2, 4, 5 and 7 are avirulent on cultivars with r2 (inducing t ...19989701811
characterization of carrot root oil arising from supercritical fluid carbon dioxide extraction.carrot root oil (sco), obtained by supercritical fluid carbon dioxide (sc-co2) extraction, was characterized and compared to a commercial carrot oil (mco) and a virgin olive oil (voo) (cv. coratina). sco showed much higher contents of carotenes, phenolics, waxes, phytosterols, and sesquiterpene and monoterpene volatiles. in sco, the most prominent components present in the fully investigated analytical fractions (fatty acids, triglycerides, waxes, phytosterols, long-chain aliphatic alcohols, sup ...200415264917
the rpg gene of medicago truncatula controls rhizobium-directed polar growth during infection.rhizobia can infect roots of host legume plants and induce new organs called nodules, in which they fix atmospheric nitrogen. infection generally starts with root hair curling, then proceeds inside newly formed, intracellular tubular structures called infection threads. a successful symbiotic interaction relies on infection threads advancing rapidly at their tips by polar growth through successive cell layers of the root toward developing nodule primordia. to identify a plant component that cont ...200818621693
plant peptides govern terminal differentiation of bacteria in symbiosis.legume plants host nitrogen-fixing endosymbiotic rhizobium bacteria in root nodules. in medicago truncatula, the bacteria undergo an irreversible (terminal) differentiation mediated by hitherto unidentified plant factors. we demonstrated that these factors are nodule-specific cysteine-rich (ncr) peptides that are targeted to the bacteria and enter the bacterial membrane and cytosol. obstruction of ncr transport in the dnf1-1 signal peptidase mutant correlated with the absence of terminal bacteri ...201020185722
community- and genome-based views of plant-associated bacteria: plant-bacterial interactions in soybean and rice.diverse microorganisms are living as endophytes in plant tissues and as epiphytes on plant surfaces in nature. questions about driving forces shaping the microbial community associated with plants remain unanswered. because legumes developed systems to attain endosymbioses with rhizobia as well as mycorrhizae during their evolution, the above questions can be addressed using legume mutants relevant to genes for symbiosis. analytical methods for the microbial community have recently been advanced ...201020685969
activity-directed identification of maize kernel peroxidases associated with postharvest insect resistance.maize grain peroxidases are associated with insect resistance. in this study we present an activity directed approach for the identification of peroxidases localized in different grain tissues. with drastically reduced proteomic effort we could identify different peroxidases for maize weevil susceptible and resistant genotypes of maize. our strategy also allows for the identification of previously unknown plant peroxidases.201020721399
expression and plasma membrane localization of the mammalian b-cell receptor complex in transgenic nicotiana tabacum.the b-cell antigen receptor (bcr), displayed on the plasma membrane of mature b cells of the mammalian immune system, is a multimeric complex consisting of a membrane-bound immunoglobulin (mig) noncovalently associated with the igα/igβ heterodimer. in this study, we engineered transgenic tobacco plants expressing all four chains of the bcr. elisa, western blotting and confocal microscopy demonstrated that the bcr was correctly assembled in plants, predominantly in the plasma membrane, and that t ...201120860562
dna barcodes for mexican cactaceae, plants under pressure from wild collecting.dna barcodes could be a useful tool for plant conservation. of particular importance is the ability to identify unknown plant material, such as from customs seizures of illegally collected specimens. mexican cacti are an example of a threatened group, under pressure because of wild collection for the xeriscaping trade and private collectors. mexican cacti also provide a taxonomically and geographically coherent group with which to test dna barcodes. here, we sample the matk barcode for 528 speci ...201121457479
genus identification of toxic plant by real-time pcr.some plants have toxicities that are dangerous for humans. in the case of poisoning by toxic plants, a rapid and easy screening test is required for accurate medical treatment or forensic investigation. in this study, we designed specific primer pairs for identification of toxic plants, such as subgenus aconitum, genus ricinus, genus illicium, and genus scopolia, by internal transcribed spacer sequences of nuclear ribosomal dna. allied species of target plants, foods, and human dna were not dete ...201120623131
a brief review of molecular techniques to assess plant diversity.massive loss of valuable plant species in the past centuries and its adverse impact on environmental and socioeconomic values has triggered the conservation of plant resources. appropriate identification and characterization of plant materials is essential for the successful conservation of plant resources and to ensure their sustainable use. molecular tools developed in the past few years provide easy, less laborious means for assigning known and unknown plant taxa. these techniques answer many ...201020559503
stable adaptive fuzzy controllers with application to inverted pendulum adaptive fuzzy controller is constructed from a set of fuzzy if-then rules whose parameters are adjusted on-line according to some adaptation law for the purpose of controlling the plant to track a given-trajectory. in this paper, two adaptive fuzzy controllers are designed based on the lyapunov synthesis approach. we require that the final closed-loop system must be globally stable in the sense that all signals involved (states, controls, parameters, etc.) must be uniformly bounded. roughly ...199618263068
direct adaptive controller for nonaffine nonlinear systems using self-structuring neural networks.a direct adaptive state-feedback controller is proposed for highly nonlinear systems. we consider uncertain or ill-defined nonaffine nonlinear systems and employ a neural network (nn) with flexible structure, i.e., an online variation of the number of neurons. the nn approximates and adaptively cancels an unknown plant nonlinearity. a control law and adaptive laws for the weights in the hidden layer and output layer of the nn are established so that the whole closed-loop system is stable in the ...200515787148
enantioselective gas chromatography in flavor and fragrance analysis: strategies for the identification of known and unknown plant volatiles.this review describes current analytical technology for the analysis of chiral constituents in essential oils and other natural volatiles, flavor and fragrance compounds, and covers some important results achieved by natural compound chemists, food chemists, perfumers, and molecular biologists. the technique of enantioselective gas chromatography (gc) is described and applied for assigning absolute configuration of chiral natural compounds, which is strongly connected to differences in odor prop ...200415516282
plant functional genomics.functional genome analysis of plants has entered the high-throughput stage. the complete genome information from key species such as arabidopsis thaliana and rice is now available and will further boost the application of a range of new technologies to functional plant gene analysis. to broadly assign functions to unknown genes, different fast and multiparallel approaches are currently used and developed. these new technologies are based on known methods but are adapted and improved to accommoda ...200212146788
a long-tailed, seed-eating bird from the early cretaceous of china.the lacustrine deposits of the yixian and jiufotang formations in the early cretaceous jehol group in the western liaoning area of northeast china are well known for preserving feathered dinosaurs, primitive birds and mammals. here we report a large basal bird, jeholornis prima gen. et sp. nov., from the jiufotang formation. this bird is distinctively different from other known birds of the early cretaceous period in retaining a long skeletal tail with unexpected elongated prezygopophyses and ch ...200212140555
immunostimulation in the rainbow trout (oncorhynchus mykiss) following intraperitoneal administration of ergosan.the present work provides information concerning the immunostimulatory activity of ergosan, an algal based product, injected intraperitoneally in the rainbow trout (oncorhynchus mykiss). ergosan is composed of 0.002% unspecified plant extract, 1% alginic acid from laminaria digitata, and 98.998% algal based carrier. migration of leucocytes into the peritoneal cavity was stimulated at doses > or =1 mg ml(-1). a single dose of 1mg significantly augmented the proportion of neutrophils, degree of ph ...200211943333
cloning of a cdna encoding a developmentally regulated 22 kda polypeptide from tobacco leaf plasma membrane.a polypeptide doublet (p18-p19, ca 22 kda, pi 4.5) has been shown to accumulate in tobacco leaf plasma membrane in a development-dependent way, under constant environmental conditions. p18 and p19 were purified by 2d-page and microsequenced. microsequences revealed only small differences between the two polypeptides. a pcr-based cloning strategy identified a cdna displaying a 591 bp orf. the encoded polypeptide contained p19 specific microsequences. it was expressed in e. coli and a specific rab ...19968908355
an overview of the food intake patterns of the cayo santiago rhesus monkeys (macaca mulatta): report of a pilot study.the food ingestion patterns of the rhesus monkeys (macaca mulatta) of group l on cayo santiago were quantitatively recorded during two months which coincided with the annual breeding season. three methods of sampling were used concurrently: interval scan sampling, group location mapping and focal animal observation. these data generated time budgets and specifics about foods selected by six age/sex classes of animals. overall the animals spent 10.8% of their time engaged in eating. this eating t ...19892780973
autophosphorylation profiling of arabidopsis protein kinases using the cell-free system.protein phosphorylation is one of the main process in the signal transduction pathway. in recent years, there has been increasing attention to plant phosphorylation signaling and many laboratories are trying to elucidate pathways using various approaches. although more than 1000 protein kinase (pk) genes have been annotated in the arabidopsis genome, biochemical characterization of those pks is limited. in this work, we demonstrate high-throughput profiling of serine/threonine autophosphorylatio ...201121477822
atradidymella muscivora gen. et sp. nov. (pleosporales) and its anamorph phoma muscivora sp. nov.: a new pleomorphic pathogen of boreal bryophytes.during a survey of bryophilous fungi from boreal and montane habitats, 12 isolates of a hitherto unknown plant pathogenic member of the pleosporales were recovered from aulacomnium palustre, hylocomium splendens, and polytrichum juniperinum, and described as atradidymella muscivora gen. et sp. nov. atradidymella is characterized by minute, unilocular, setose pseudothecia having 2-3 wall layers; brown, fusiform, 1-septate ascospores; and a phoma anamorph. the genus is distinguished from all other ...200921628277
ectopic expression of an esterase, which is a candidate for the unidentified plant cutinase, causes cuticular defects in arabidopsis thaliana.cutinase is an esterase that degrades the polyester cutin, a major component of the plant cuticle. although cutinase activity has been detected in pollen, the genes encoding this enzyme have not been identified. here, we report the identification and characterization of arabidopsis cdef1 (cuticle destructing factor 1), a novel candidate gene encoding cutinase. cdef1 encodes a member of the gdsl lipase/esterase family of proteins, although fungal and bacterial cutinases belong to the alpha/beta h ...201019996150
the role of plant biosecurity in preventing and controlling emerging plant virus disease epidemics.a number of research strategies have been initiated over the last decade to enhance plant biosecurity capacity at the pre-border, border and post-border frontiers. in preparation for emerging plant virus epidemics, diagnostic manuals for economically important plant viruses that threaten local industries have been developed and validated under local conditions. contingency plans have also been prepared that provide guidelines to stakeholders on diagnostics, surveillance, survey strategies, epide ...200919152816
radial basis function neural network for approximation and estimation of nonlinear stochastic dynamic systems.this paper presents a means to approximate the dynamic and static equations of stochastic nonlinear systems and to estimate state variables based on radial basis function neural network (rbfnn). after a nonparametric approximate model of the system is constructed from a priori experiments or simulations, a suboptimal filter is designed based on the upper bound error in approximating the original unknown plant with nonlinear state and output equations. the procedures for both training and state e ...199418267832
identification of extended hammerstein systems using dynamic self-optimizing neural this paper, a new dynamic self-optimizing neural network (dsonn) with online adjusting hidden layer and weights is proposed for a class of extended hammerstein systems with non-gaussian noises. input vector to the network is first determined by means of system order estimation using a designated input signal. then the hidden layer is generated online, which consists of a growing step according to the plant dynamics and a revised pruning step used to refine the hidden structure such that the g ...201121708500
learning rules for neuro-controller via simultaneous perturbation.this paper describes learning rules using simultaneous perturbation for a neurocontroller that controls an unknown plant. when we apply a direct control scheme by a neural network, the neural network must learn an inverse system of the unknown plant. in this case, we must know the sensitivity function of the plant using a kind of the gradient method as a learning rule of the neural network. on the other hand, the learning rules described here do not require information about the sensitivity func ...199718255714
gas chromatographic and mass spectrometric investigations of organic residues from roman glass unguentaria.a combination of gas chromatographic (gc) and mass spectrometric (ms) techniques, including direct exposure-ms (de-ms), high-temperature gc-ms (htgc-ms) and gc-ms of neutral and acid fractions, was employed to study the composition and recognise origin of the organic materials used to manufacture balm residues surviving in a series of glass unguentaria recovered from excavations of a roman villa (villa b) in the ancient town of oplontis (naples, italy). de-ms provided comprehensive 'fingerprint' ...200818243222
the big unknown: plant virus biodiversity.studies on plant virus biodiversity are in their infancy, but with new technologies we can expect to see more information about novel plant viruses in the near future. the challenge for virus biodiversity work is that viruses do not have any universal coding sequence, such as ribosomal rnas found in all cellular life. these obstacles are being overcome in clever ways. understanding what exists in our natural environment will help us to tackle big issues in agriculture, such as disease emergence ...201122440569
new method for pollen identification by ft-ir spectroscopy.a new methodology for identification of pollen was developed based on ft-ir spectroscopy. pollen samples of twenty different plant species were collected and the diffuse reflectance infrared fourier transform (drifts) and kbr pellet spectra were recorded. libraries of spectra were created. spectra of unknown plant origin pollen were recorded and compared with those of the corresponding pollen library and the match value was measured automatically using the appropriate software (ominc ver. 3.1). ...200314610932
transcriptome analysis during cell division in plants.using synchronized tobacco bright yellow-2 cells and cdna-amplified fragment length polymorphism-based genomewide expression analysis, we built a comprehensive collection of plant cell cycle-modulated genes. approximately 1,340 periodically expressed genes were identified, including known cell cycle control genes as well as numerous unique candidate regulatory genes. a number of plant-specific genes were found to be cell cycle modulated. other transcript tags were derived from unknown plant gene ...200212393816
natural history and information overload: the case of linnaeus.natural history can be seen as a discipline paradigmatically engaged in 'data-driven research.' historians of early modern science have begun to emphasize its crucial role in the scientific revolution, and some observers of present day genomics see it as engaged in a return to natural history practices. a key concept that was developed to understand the dynamics of early modern natural history is that of 'information overload.' taxonomic systems, rules of nomenclature, and technical terminologie ...201122326068
development of sts and caps markers for identification of three tall larkspurs (delphinium spp.).one cleaved amplified polymorphic sequence (caps) and nine sequence tagged site (sts) markers were developed for identifying tall larkspur (delphinium spp.) plants in three species based on the dna sequence of known species-specific rapd markers. four sts markers were used for identification of delphinium occidentale, three sts markers for delphinium barbeyi, and one caps and two sts markers for delphinium glaucum. one hundred sixty-six individual plants collected at 19 locations in the western ...200211962619
biological activity of guanacastepene, a novel diterpenoid antibiotic produced by an unidentified fungus cr115.fermentation extracts of culture cr115, an unknown plant endophyte originally isolated from costa rica, were found to be active against antibiotic-resistant bacteria. the metabolite responsible for activity was identified as a novel diterpenoid antibiotic guanacastepene (mol. wt. 374.47 and mol. formula c22h30o5). mechanistic studies done in an e. coli imp strain suggested membrane damage as the primary mode of bactericidal action. this compound also lysed human rbcs and caused leakage of intrac ...200010819296
epidermis-specific gene expression in pachyphytum.transcripts of exclusively epidermis-specific expression were obtained by differential screening of a cdna library prepared from isolated epidermis tissue of a succulent plant, pachyphytum. six transcripts were selected and characterized by rna gel blot hybridization. five cdnas represented abundant mrnas found exclusively in the epidermis. in situ hybridizations with three of these transcripts further substantiated their epidermal location. while two transcripts were present in all cells of the ...19921446168
on modeling center of foot pressure distortion through a medium.the center of foot pressure (cop) is a commonly used output measure of the postural control system as it is indicative of the systems stability. a dense piece of foam, i.e., a sponge, can be used to emulate random environmental conditions that distort the ground reaction forces received and interpreted by the cutaneous sensors in the feet; thus introducing uncertainty into the control system. in this paper, the density and size of the sponge was selected such that a subject's weight did not caus ...200515759564
investigative proteomics: identification of an unknown plant virus from infected plants using mass spectrometry.we describe the identification of a previously uncharacterized plant virus that is capable of infecting nicotiana spp. and arabidopsis thaliana. protein extracts were first prepared from leaf tissue of uninfected tobacco plants, and the proteins were visualized with two-dimensional electrophoresis (2-de). matching gels were then run using protein extracts of a tobacco plant infected with tobacco mosaic virus (tmv). after visual comparison, the proteins spots that were differentially expressed in ...200312837595
application of microscopy in authentication of valuable chinese medicine i-cordyceps sinensis, its counterfeits, and related products.light and polarized microscope was applied to authenticate 32 cordyceps and 6 artificial counterfeits and 8 fermented cordyceps as well as 7 cordyceps capsules available in hong kong markets. results showed that transverse sections of stroma and powder of larvae can be used to differentiate c. sinensis from its counterfeits. the fermented cordyceps are in powder form. among the eight fermented cordyceps collected, half of them were pure; three were a mixture of fermented cordyceps and soya beans ...201121618656
construction of a directory of tobacco plasma membrane proteins by combined two-dimensional gel electrophoresis and protein sequencing.the polypeptide pattern of the plasma membrane from tobacco was studied by two-dimensional gel electrophoresis. when using classical carrier ampholyte isoelectric focusing/sodium dodecyl sulfate-polyacrylamide gel electrophoresis (ief/sds-page) approximately 400 polypeptide spots were detected after silver staining and computer analysis using the quest software. this resolution was sufficient to assess physiological effects such as changes in a phytohormone concentration. by using ph 4-8 immobil ...19979150956
suppression of beta-1,3-glucanase transgene expression in homozygous plants.a chimeric construct containing the nicotiana plumbaginifolia beta-1,3-glucanase gn1 gene was introduced into nicotiana tabacum sr1 to produce high levels of the enzyme constitutively. we determined that the gn1 protein represents a basic beta-1,3-glucanase isoform which accumulates into the vacuoles of the transgenic plants. analysis of the progeny of the transgenic plant with the highest levels of gn1 expression revealed an unexpected phenomenon of gene suppression. plants hemizygous for the t ...19921378394
proteolytic system of plant mitochondria.the existence of a proteolytic system which can specifically recognize and cleave proteins in mitochondria is now well established. the components of this system comprise processing peptidases, atp-dependent peptidases and oligopeptidases. a short overview of experimentally confirmed proteases mainly from arabidopsis thaliana is provided. the role of the mitochondrial peptidases in plant growth and development is emphasized. we also discuss the possibility of existence of as yet unidentified pla ...201122085399
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