bluuebunny/crossref_metadata_2025_split huggingface dataset:
Factors shaping the spatial variation of weed communities across a landscape mosaic
Authors: ALIGNIER A , PETIT S 
Published: July 2012

Alignier A & Petit S (2012). Factors shaping the spatial variation of weed communities across a landscape mosaic. Weed Research.52, 402–410.SummaryThe spatial pattern of weeds within field is widely accepted to be aggregated, but few studies have assessed the spatial structure of weed communities at the landscape scale. Using a combination of aggregation measures and similarity indices, this study aimed at inferring the processes behind the spatial patterning of weed communities. We analysed spatial variation in the species composition of weed communities to understand how similarity in weed composition varies with field and spatial effects. Weeds were surveyed in a regular grid sampling a 110 ha landscape mosaic made up of 24 fields. We showed that weed composition similarity among samples exhibited an aggregated pattern at the mosaic scale, of up to 400 m. Similarity in weed composition varied mainly among fields, but also within field according to the distance from the field border. The decay in species similarity was influenced both by field and spatial effects. Spatial effect remains signifi‐cant after controlling for field effect. These findings provide support for the hypothesis that niche relationships and dispersal processes are both involved in the spatial patterning of weed species composition at the mosaic scale.
Identification of a dicer homologue gene (DCL2) in Nicotiana tabacum
Authors: Udriste A. A. , Stan V. , Radu G. L. , Tabler M. , Cucu N. 
Published: July 2012

AbstractEukaryotes possess a mechanism that generates small interfering RNA (siRNA) and microRNA (miRNA) and use these to regulate gene expression at the transcriptional or post‐transcriptional level. These small RNAs (21–24nt) are processed from long double‐stranded RNA precursors by type III RNase enzymes, referred to as DICER or DICER‐LIKE proteins (DCLs). In Arabidopsis, there are four DCL genes and their role in small RNA biogenesis and silencing has been the subject of intense study. DCL2 is less well studied than the other DCL proteins although it is known to play a role in formation of natural antisense siRNA and may be involved in transitive silencing of transgene transcripts. This study provides basic genomic information on DCL2 in the Nicotiana tabacum (NtDCL2) gene family and its probable roles in plant growth and development.
Histochemical Distribution of Digestive Enzymes in the Intestine of the Common Two‐Banded SeaBream, Diplodus vulgaris, Geoffroy St‐Hilaire 1817
Authors: Tlak Gajger I. , Nejedli S. , Kozarić Z. 
Published: July 2012

SummaryThe histochemical localization of non‐specific esterase, alkaline and acid phosphatase as well as aminopeptidase in the intestine of the free‐living common two‐banded sea bream (Diplodus vulgaris) was investigated. Fish were caught near the town of Zadar (Adriatic Sea, Croatia). Samples of pyloric caeca and three parts of the intestine proper (anterior, middle and posterior) were used for the description of non‐specific esterase, alkaline and acid phosphatase as well as aminopeptidase. Non‐specific esterase activity was found in the cytoplasm of enterocytes in pyloric caeca and in all investigated intestinal segments. The activity was stronger in the anterior and posterior part of the intestine than in the pyloric caeca and middle segment of the intestine. Intestinal alkaline phosphatase was detected in brush border of enterocytes of all investigated intestinal segments. Enzymatic activity gradually decreased in a posterior direction. Acid phosphatase activity was observed as a fine granular reaction product in the supranuclear region of enterocytes. This activity was almost equal in pyloric caeca as well as in the anterior intestinal segment, while it was stronger in the middle and posterior intestinal segment. Aminopeptidase was present along the intestinal epithelium brush border in all investigated parts of the digestive tube. The intensity of aminopeptidase increased posteriorly. The possible role of investigated enzymes in intracellular digestion and transport is discussed.
Biological Characterization and Complete Genome Sequence of a Possible Strain of Indian cassava mosaic virus from Jatropha curcas in India
Authors: Snehi Sunil Kumar , Srivastava Ashish , Raj Shri Krishana 
Published: July 2012

AbstractThe outbreak of a severe mosaic disease with a significant incidence was noticed on Jatropha curcas plants growing in Lucknow, Northern India. The causal virus was successfully transmitted by whiteflies (Bemisia tabaci) and grafting from naturally infected to healthy J. curcas plants. The association of Begomovirus with the mosaic disease of J. curcas was detected by PCR using primers specific to DNA‐A of Begomoviruses. Further, full‐length DNA‐A genome of ∼2.7 kb was amplified by RCA followed by digestion with Bam HI restriction enzyme. Cloning and sequencing of obtained amplicons resulted in 2740 nucleotides of complete DNA‐A consisting of six ORFs and IR region (GenBank Accession HM230683). The sequence analysis revealed highest 85% similarities with Jatropha curcas mosaic virus, 77–84% with Indian cassava mosaic virus and 73–76% with Sri Lankan cassava mosaic virus isolates. Phylogenetic analysis of the Begomovirus isolate also showed a clear‐cut distinct relationship with earlier reported Begomoviruses from Jatropha curcas and other Begomoviruses. On the basis of the guidelines of the International Committee on Taxonomy of Viruses (ICTV‐2008), our virus isolate was identified as a possible strain of Indian cassava mosaic virus, and its name Jatropha mosaic India virus (JMIV) is proposed.
Morphological, biochemical and phylogenetic assessments of water‐bloom‐forming tropical morphospecies of Microcystis (Chroococcales, Cyanobacteria)
Authors: Le Ai Nguyen Vinh , Tanabe Yuuhiko , Matsuura Hiroshi , Kaya Kunimitsu , Watanabe Makoto M. 
Published: July 2012

SUMMARYPrevious polyphasic analyses of five morphospecies of the water‐bloom‐forming cyanobacterial genus Microcystis, Microcystis aeruginosa (Kützing) Lemmermann (=Microcystis aeruginosa (Kützing) Kützing), Microcystis ichthyoblabe Kützing, Microcystis novacekii (Komárek) Compère, Microcystis viridis (A. Braun) Lemmermann, and Microcystis wesenbergii (Komárek) Komárek in Kondratieva, have shown them to be conspecific and they have been proposed to be included under the binomial Microcystis aeruginosa (Kützing) Lemmermann. However, several morphospecies from tropical regions, such as Microcystis bengalensis Banerji, Microcystis panniformis Komárek, Komárková‐Legnerová, Sant'anna, Azevedo & Senna, Microcystis protocystis Crow, Microcystis pseudofilamentosa Crow, Microcystis ramosa Bharadwaya, and Microcystis robusta (Clark) Nygaard, have never been analyzed biochemically or phylogenetically; consequently, their taxonomic status is uncertain. To resolve this issue, we collected 57 strains of Microcystis from Vietnam for taxonomic analysis using a polyphasic approach. Strains were assigned to the six tropical morphospecies listed above or to four morphospecies with cosmopolitan distributions (M. aeruginosa, M. ichthyoblabe, M. novacekii, and M. wesenbergii). Several strains produced colony variants in different culture media; some of these variants had forms that overlapped with those of other morphospecies. Cell diameters varied widely between strains (2.6–9.3 µm) and were unrelated to morphospecies discrimination criteria. Strains of the 10 morphospecies examined had similar fatty acid compositions and closely similar 16S rRNA gene sequences (>99.2% similar). Phylogenetic analyses using 16S rRNA gene and 16S–23S internal transcribed spacer sequences did not identify any clear separations corresponding to morphospecies concepts or microcystin‐producing abilities. Thus, the six tropical morphospecies (M. bengalensis, M. panniformis, M. protocystis, M. pseudofilamentosa, M. ramosa, and M. robusta) are not natural taxonomic units within the genus Microcystis and should be included under M. aeruginosa.
Iridal coloboma induces dyscoria during miosis in FLS mice
Authors: Matsuura Tetsuro , Tsuji Naho , Kodama Yasushi , Narama Isao , Ozaki Kiyokazu 
Published: July 2012

AbstractObjective  Fatty liver Shionogi (FLS) mice exhibit characteristic retinochoroidal coloboma because of a failure in fusion of the embryonic optic fissure. However, the same pathogenesis should result in iridal coloboma that has not been reported in this strain. The purpose of this study was to describe the physiologic and morphometric changes in iridal tissue involved in ocular coloboma in FLS mice.Procedures  The miotic response after light exposure was evaluated in three strains of live mice, and the shape and location of the pupil were judged macroscopically. Subsequently, macroscopic abnormalities in the anterior segment and fundus were observed postmortem in all mice. During miotic and mydriatic responses in the eyes of live male FLS mice with dyscoric and normal pupils, each iris was measured in four radial directions. The enucleated eyes were examined morphometrically and histologically in both sexes of FLS mice.Results  Inferior corectopia upon light‐induced miosis was clearly detected in live FLS mice. The deviated pupils were not round but oval‐shaped. Clinical and postmortem examination revealed that all dyscoric eyes had hypoplastic and dysfunctional irides inferiorly in FLS mice. Histopathological examination confirmed that both the dilator and sphincter muscles and iris stroma were quantitatively diminished in the affected inferior iris. Meanwhile, the rate of fundus (retinochoroidal) coloboma in eyes exhibiting dyscoria was remarkably high, although some dyscoric eyes had no fundus coloboma.Conclusions  Fatty liver Shionogi mice had iridal coloboma, resulting in inferior corectopia upon light‐induced miosis as an indicator of ocular coloboma.
Canine ocular tumors following ciliary body ablation with intravitreal gentamicin
Authors: Duke Felicia D. , Strong Travis D. , Bentley Ellison , Dubielzig Richard R. 
Published: July 2012

AbstractIridociliary tumors are the second most common primary ocular tumor in dogs and are usually benign. A review of the Comparative Ocular Pathology Laboratory of Wisconsin (COPLOW) database in 2009 suggested a potential correlation between malignant iridociliary epithelial tumors and ciliary body ablation by intravitreal gentamicin injection for the treatment of glaucoma. The purpose of this case series was to determine whether there is evidence of such a correlation in the COPLOW collection. Mining of the COPLOW database revealed that a significant number (39.5%) of canine globes with a history of ciliary body ablation were subsequently diagnosed with primary ocular tumors at enucleation, most commonly iridociliary epithelial tumors and melanocytic tumors. It is possible that neoplasia was present but unrecognized at the time of ciliary body ablation. These tumors had a higher than expected incidence of malignancy. These cases underscore the importance of reserving ciliary body ablation with gentamicin for disease‐free eyes.
Histological and histochemical study of the duodenum of the plains viscacha (Lagostomus maximus) at different stages of its ontogenetic development
Authors: Tano de la Hoz María Florencia , Flamini Mirta Alicia , Díaz Alcira Ofelia 
Published: July 2012

AbstractThe general objective of this study focused on the duodenal histological and histochemical analysis of fetuses and adults of plains viscacha (Lagostomus maximus) from the Buenos Aires province (Argentina). Histological techniques, histochemical procedures for localizing and characterizing glycoproteins (GPs) and lectin histochemical techniques for the identification of specific sugar residues were used. The duodenal structure of all age groups here considered was typical of mammals. We identified a proliferation phase and an epithelial morphogenesis in mid‐gestational fetuses, an intermediate period of cell differentiation in at‐term fetuses and a posterior stage of physiological maturation in adults. According to histochemistry, the diverse GPs elaborated and secreted into the duodenum show a high degree of histochemical complexity related to the multiple functions of mucus in the digestive tract. The GPs in the duodenum of L. maximus and their glycosylation patterns varied according to the animal's age and the developmental state of the organ.
Conservation planning under climate change: accounting for adaptive potential and migration capacity in species distribution models
Authors: Hamann Andreas , Aitken Sally N. 
Published: July 2012

AbstractAimA number of assumptions underpinning the use of species distribution models to predict biological responses to climate change are violated for temperate and boreal tree species that are widespread, long‐lived and genetically adapted to local climate conditions. To address this situation, we propose a methodology to account for the potential effects of genetic structure, adaptive potential and limited migration capacity.LocationBritish Columbia, Canada.MethodsSimilar to the widely used ‘no migration’ and ‘unlimited migration’ scenarios, we employ more refined biological response scenarios to evaluate the potential effects of genetic adaptation to local environments and the capacity of species to adapt and migrate. These scenarios are realized by two sets of geographic delineations that partition the species range into multiple populations and that subdivide the study area into smaller landscape units.ResultsIn a case study for British Columbia, we demonstrate how the approach can be used to evaluate the adequacy of a reserve system of 906 protected areas to ensure long‐term maintenance of forest genetic resources for 48 tree species. We find that between 35% and 85% of locally adapted populations in protected areas are maintained under a median climate change scenario until the end of the century. A sensitivity analysis shows that assumptions about migration and adaptation capacity of species have a major effect on the projected conservation status.Main conclusionsWe propose that the results of species distribution models have practical value for conservation planning if the focus is on maintenance rather than loss of suitable habitat. Accounting for genetic structure, adaptive potential and migration capacity through best‐case and worst‐case scenarios provide important information to effectively allocate limited resources available for conservation action.
EFFECT OF CHAIN LENGTH OF ALIPHATIC AMINES ON HISTAMINE POTENTIATION AND RELEASE
Authors: MONGAR J. L. 
Published: July 2012

Diamines in the series NHa.(CH2)n.NH2 specifically potentiate histamine contractions of the guinea‐pig ileum and inhibit the enzymatic destruction of histamine. These activities are greatest with short‐chain compounds (n⋍5). Diamines also release histamine from isolated tissues and depress the contractility of plain muscle and the motility of paramecia. These activities increase with chain‐length and are probably limited only by solubility. The parallelism between histamine‐releasing activity and toxicity also extends to the monoamines in the series CH3.(CH2)n‐1.NH2. Histamine‐releasing activity of both series increases with increase of pH and can mainly be attributed to the non‐ionized base.From the results on the effect of chain‐length and ionization on activity, it is suggested that aliphatic amines release histamine by penetration of the cell membrane in the non‐ionized form, followed by exchange in the ionic form with intracellular histamine.
THE INHIBITORY ACTION OF SOME ANTIMALARIAL DRUGS AND RELATED COMPOUNDS ON THE HEXOKINASE OF YEAST AND OF PLASMODIUM BERGHEI
Authors: FRASER DOROTHY M. , KERMACK W. O. 
Published: July 2012

Of various antimalarial compounds tested, only proguanil failed to inhibit yeast hexokinase. The metabolite of proguanil, 10,580, was an effective inhibitor. Some compounds tested which were without antimalarial activity were potent inhibitors of yeast hexokinase. The degree of inhibition increased as the time during which the enzyme had been in contact with the drug increased, and the inhibitory action of mepacrine was reduced when the concentration of ATP was raised. The inhibition of yeast hexokinase by 10,732 was independent of the concentration of ATP.The hexokinase of haemolysates of the reticulocytes of mouse or rat blood was not appreciably higher than that of similar haemolysates of normal erythrocytes. Preparations of mouse or rat erythrocytes parasitized with P. berghei possessed a much higher hexokinase activity.The inhibiting action of various compounds on the hexokinase of P. berghei closely resembled those with yeast hexokinase. Again all antimalarial compounds (apart from proguanil) inhibited the enzyme, but some of the most potent inhibitors were devoid of antimalarial action. Amongst the chemotherapeutically active compounds, there appeared to be an approximate parallelism between antimalarial activity and potency as inhibitors of plasmodial hexokinase. The action of mepacrine on plasmodial hexokinase was reduced by raising the concentration of ATP, but, as with yeast hexokinase, the inhibition by 10,732 was independent of the ATP concentration.From a consideration of the results, it seems doubtful whether this type of inhibitory effect plays more than a minor part in the mechanism of antimalarial action in vivo.
HISTAMINE RELEASE INHIBITION IN VITRO AND ANTIANAPHYLACTIC EFFECTS IN VIVO OF SOME CHEMICAL COMPOUNDS
Authors: McINTIRE F. C. , RICHARDS R. K. , ROTH L. W. 
Published: July 2012

Several different types of compounds inhibited the release of histamine from the “platelet fraction” of rabbit blood when antigen was added to the blood of a sensitized rabbit in vitro. These compounds were all very toxic in vivo and could be tested only at low levels for their ability to protect animals against anaphylaxis. None of the compounds gave significant protection to sensitized animals when antigen was given intravenously. Three compounds protected animals against antigen administered as an aerosol. None of these showed any promise of clinical usefulness.Of a number of compounds which have been reported to alleviate allergic symptoms, or to protect against anaphylaxis, none prevented the release of histamine in vitro to any considerable extent.
PHARMACOLOGICAL ACTIONS OF PURE MUSCARINE CHLORIDE
Authors: FRASER P. J. 
Published: July 2012

The action of chromatographically pure crystalline muscarine chloride, prepared from Amanita muscaria, has been compared with acetylcholine chloride (ACh) on a number of different organs from a variety of species. Muscarine caused spasm in vivo and in vitro of muscles of the gut, uterus, urinary bladder, and bronchus. It also caused contraction of the horse ureter and carotid artery chain in vitro and slowed the isolated auricles of the guinea‐pig and rabbit, and the frog heart.Muscarine caused a drop in blood pressure, although in vitro it produced either constriction or dilatation of the blood vessels of the rabbit ear.All these actions resembled those of acetylcholine, though muscarine was usually more potent. Muscarine effects were readily prevented by atropine sulphate. It had a slight action on the frog rectus abdominis muscle, causing a contracture at high concentrations. Muscarine was destroyed neither by pepsin nor by boiling at any pH. It was inactive by mouth in a monkey in a quantity many times that which would cause poisoning by ingestion of Amanita muscaria in the human being. Muscarine neither inhibited nor was hydrolysed by either true‐ or pseudo‐cholinesterase. Muscarine chloride did not cause paralysis of the neuromuscular junctions of the rat diaphragm or of the cat gastrocnemius.
THE ACTION OF NITROPHENOLS ON THE METABOLIC RATE OF RATS
Authors: CAMERON MARGARET A. M. 
Published: July 2012

The effect of the mono‐ and di‐nitrophenols and certain related compounds has been determined on the rate of oxygen consumption, the rate of carbon dioxide output and the rectal temperature of the Wistar albino rat.Of the compounds examined, only 2:4‐dinitrophenol and its derivative, 3:5‐dinitro‐o‐cresol, stimulated metabolic rate. 2‐Nitrophenol and 2:3‐, 2:6‐, and 3:5‐dinitrophenol produced no change in metabolic rate; 3‐nitrophenol and 2:5‐dinitrophenol had no action on carbon dioxide production although they caused a decrease in oxygen consumption. 4‐Nitrophenol and 3:4‐dinitrophenol increased only the rate of carbon dioxide output; 2‐amino‐4‐nitrophenol increased the rate of carbon dioxide output and decreased the rate of oxygen consumption; 4‐amino‐2‐nitrophenol caused depression of metabolic rate.It was confirmed that neither rectal temperature nor carbon dioxide output could replace rate of oxygen consumption as a reliable index of metabolic stimulant action. An apparatus is described which facilitates measurement of the oxygen consumption of small mammals.
THE INHIBITORY ACTION OF MORPHINE ON THE CONTRACTION OF THE LONGITUDINAL MUSCLE COAT OF THE ISOLATED GUINEA‐PIG ILEUM
Authors: KOSTERLITZ H. W. , ROBINSON JUDITH A. 
Published: July 2012

Morphine (0.05 to 0.1 μg./ml.) markedly inhibited the contractions of the isolated guinea‐pig ileum caused by nicotine, barium, and 5‐hydroxytryptamine while the actions of acetylcholine, carbachol, and histamine were affected only a little. Atropine (0.025 to 0.05 μg./ml.) had a similar effect, in addition to its known effects on acetylcholine and carbachol contractions. Morphine had no additional effect on the inhibitory action of atropine, while in the presence of morphine, atropine had a significant additional inhibitory action only on the contraction caused by nicotine.The action of barium was complex. It caused contractions of a rhythmic type alternating with relaxations, a pattern which is similar to that produced by the emptying phase of the peristaltic reflex; these oscillations were inhibited by hexamethonium. On the other hand, that part of the sustained barium contraction which was inhibited by morphine may be explained by an action on the nerve cells innervating the muscle fibres (motor neurones). Similarly, the morphine‐sensitive component of the 5‐hydroxytryptamine (5‐HT) contraction was probably also due to an action on the motor neurones. The morphine‐insensitive contractions of barium, 5‐HT, and nicotine were believed to be caused by a direct action on the muscle fibres.The morphine inhibitors, nalorphine and levallorphan, had different effects with the different agonists. Their morphine‐like action was particularly pronounced on the effect of 5‐HT, which they antagonized, while their morphine‐protecting action was most strongly present on the effect of nicotine.
SOME EFFECTS OF RESERPINE AND HYDRALLAZINE UPON TISSUE RESPIRATION AND THE CONCENTRATION OF ADENOSINE NUCLEOTIDES IN CERTAIN TISSUES
Authors: KIRPEKAR S. M. , LEWIS J. J. 
Published: July 2012

The effects of reserpine and hydrallazine upon the oxygen uptake of preparations of rat brain, liver, and kidney and rabbit aorta have been investigated using the Warburg “Direct” method. In these tissues reserpine did not significantly stimulate respiration at any of the doses used. Concentrations of 10 or 50 μg./ml. had no significant effect upon respiration, but higher doses (330 μg./ml.) depressed it in all the tissues studied. This effect was also seen in rat brain at a reserpine concentration of 100 μg./ml. which had no significant effect in other tissues. Hydrallazine (50 or 100 μg./ml.) depressed respiration in all tissues studied. Stimulation at lower doses was not seen.After sublethal doses of reserpine, depletion of energy rich phosphate compounds occurred in brain and liver but not in skeletal muscle and heart. Hydrallazine also depleted brain of energy rich phosphate compounds, but did not affect liver, heart, or skeletal muscle. The bearing of these results on the mode of action of reserpine and hydrallazine is discussed.