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PubMed2006

Effects of oxalate and phosphate on the release of arsenic from contaminated soils and arsenic accumulation in wheat.

Oxalate is exuded by plants in the rhizosphere and plays an important role in the soil/root interactions. Phosphate fertilizer is widely used all over the world and may influence the behavior of arsenic (As) in soils. In this study oxalate and phosphate were used as extractants to investigate their effects on the release of As from three As-contaminated soils and the chemical speciation of As. Concentrations of arsenite (As(III)) and arsenate (As(V)) released progressively increased by increasing the concentrations of oxalate or phosphate. The released As(V) content was higher than that of As(III) and the differences between As(V) and As(III) released by oxalate was more obvious than by phosphate. Greenhouse experiment was conducted to evaluate the effects of oxalate and phosphate on As uptake by wheat (Triticum vulgare L.). Addition of oxalate or phosphate resulted in the increase of As accumulation in both wheat root and shoot and the effect of phosphate was more obvious than that of oxalate.

Arsenic↗

PubMed1997

Supraciliary effusions and ciliary body thickening after scleral buckling procedures.

PURPOSE: The purpose of the study was to use ultrasound biomicroscopy to identify and quantity changes in anterior segment parameters after scleral buckling procedures. METHODS: Ultrasound biomicroscopy was used to examine 15 patients with retinal detachment within 1 week before and after surgery. Quantitative measurements were performed of anterior chamber depth, supraciliary effusion depth, ciliary body thickness, and angle opening. RESULTS: Supraciliary fluid was present after surgery in 12 patients (80%). Average supraciliary fluid depth was 0.16 +/- 0.13 mm. Ciliary body thickness measurements at a point 2-mm posterior to the scleral spur increased after surgery in all patients an average of 0.15 +/- 0.10 mm. There was a strong correlation between ciliary fluid levels and change in ciliary body thickness (r = 0.742, P < 0.01). Anterior chamber depth decreased after surgery in 14 patients (93%). A decrease of angle opening of greater than 5 degrees was noted in 11 patients (73%). In all of these 11 patients, the ciliary body and iris root were considered to be rotated anteriorly. Six (55%) of 11 of these patients showed anterior bowing of the iris, indicating pupillary block. Complete angle closure occurred over one to three quadrants in three patients, but none of these patients had complete angle closure or glaucoma. CONCLUSIONS: Supraciliary effusions and ciliary body thickening are common after scleral buckling procedures and can produce conditions conducive to angle closure. Angle narrowing occurs through a combination of direct anterior iris rotation and induced pupillary block.

Anterior Chamber↗

PubMed1982

Effects of experimentally induced fleece-rot on the structure of the skin of Merino sheep.

Four medium- and six strong-wool Merino sheep were exposed to continuous simulated rain (4 x 5 mm/h) for periods ranging from 3 to 9 days. In response, the sheep developed characteristics typical of fleece-rot lesions such as exudative encrustation and bacterial discoloration of the fleece. Skin samples were taken periodically for histological examination from the trunk region of the sheep prior to, during, and after wetting. An inflammatory response to wetting occurred in the upper layers of the dermis and this caused the release of cells which began invading the epidermis after only 6 h of wetting. An associated increased in vascular permeability was observed macroscopically following intravenous injection of Pontamine Blue dye. The incidence and extent of the inflammation increased during subsequent wetting while epidermal acanthosis and hyperkeratosis became increasingly evident. Epidermal thickness returned to pretreatment levels by 13 days after cessation of wetting when inflammatory regions were absent from most of the sheep. Cellular lysis occurred in the suprabulbar and keratogenous regions of a small proportion of follicles (1-13%) during wetting, resulting in the interruption of fibre growth and keratinization in these follicles and the occlusion of follicle hair canals with inner root sheath material ('plugs') which persisted after wetting ceased. These morphological changes in the epidermis, follicles and fleece are considered to occur as a consequence of the initial rapid inflammatory response to wetting during the developing of fleece-rot lesions.

Animals↗

PubMed1984

Spontaneous Phloem bleeding from cryopunctured fruits of a ureide-producing legume.

The vasculature of the dorsal suture of cowpea (Vigna unguiculata [L.] Walp) fruits bled a sugar-rich exudate when punctured with a fine needle previously cooled in liquid N(2). Bleeding continued for many days at rates equivalent to 10% of the estimated current sugar intake of the fruit. A phloem origin for the exudate was suggested from its high levels (0.4-0.8 millimoles per milliliter) of sugar (98% of this as sucrose) and its high K(+) content and high ratio of Mg(2+) to Ca(2+). Fruit cryopuncture sap became labeled with (14)C following feeding of [(14)C]urea to leaves or adjacent walls of the fruit, of (14)CO(2) to the pod gas space, and of [(14)C] asparagine or [(14)C]allantoin to leaflets or cut shoots through the xylem. Rates of translocation of (14)C-assimilates from a fed leaf to the puncture site on a subtended fruit were 21 to 38 centimeters per hour. Analysis of (14)C distribution in phloem sap suggested that [(14)C]allantoin was metabolized to a greater extent in its passage to the fruit than was [(14)C] asparagine. Amino acid:ureide:nitrate ratios (nitrogen weight basis) of NO(3)-fed, non-nodulated plants were 20:2:78 in root bleeding xylem sap versus 90:10:0.1 for fruit phloem sap, suggesting that the shoot utilized NO(3)-nitrogen to synthesize amino acids prior to phloem transfer of nitrogen to the fruit. Feeding of (15)NO(3) to roots substantiated this conclusion. The amino acid:ureide ratio (nitrogen weight basis) of root xylem sap of symbiotic plants was 23:77 versus 89:11 for corresponding fruit phloem sap indicating intense metabolic transfer of ureide-nitrogen to amino acids by vegetative parts of the plant.

Journal Article↗

PubMed1986

Rhizobins, a group of peptides in the free-amino-Acid pool of the soybean-Rhizobium system.

Free-living Rhizobium (according to Bergey's Manual of Systematic Bacteriology, [1984, The Williams & Wilkins Co., Baltimore], Bradyrhizobium) japonicum was found to release a peptide into the nutrient media. Soybean nodules contained this peptide and exuded it into the soil. The name "rhizobin A" is suggested for this peptide. Nodules also contained another peptide, rhizobin B, as well as an unidentified, ninhydrin-positive compound, rhizobin C. The three peptides were confined to the free-amino-acid pool of the soluble fraction and eluted consecutively from a cation-exchange column. Rhizobin A was isolated in a highly purified form; its molecular mass was approximately 1,600 daltons as determined by Sephadex gel filtration and mass spectrometry. The amino-acid composition could be determined only approximately, because a long time was necessary for acid hydrolysis, possibly due to unusual linkages. The rhizobin concentration in soybean nodules continually increased during 50 days of growth, from 2 to approximately 400 mug/g (fresh weight). When combined nitrogen was added to nodulated soybean and subsequently removed, nitrogenase activity, nodulation, and nodule growth first decreased and then recovered. The relative amount of rhizobin A followed a similar pattern. Rhizobins were not detected in the roots, stems, and leaves of nodulated soybean plants. They were present in Lupinus nodules, but absent in alder nodules.

Journal Article↗

PubMed1996

Inhibitory effects of traditional Chinese medicine Shimotsu-to and its included crude fractions on adjuvant-induced chronic inflammation of mice.

Effects of a traditional Chinese medicine, Shimotsu-to (a combined prescription of cnidium rhizome, peony root, angelica root and rehmannia root), and its included crude fractions were investigated on an adjuvant-induced chronic inflammation model of mice. The aqueous extract (30, 100 and 300 mg/kg, i.p.) of Shimotsu-to reduced the carmine content, granuloma weight, inflammation cell count and pouch fluid weight in the inflammation model, respectively. The extract of Shimotsu-to without cnidium at the same doses did not produce significant changes in these four inflammatory parameters. The same doses of extracts of Shimotsu-to without peony, and without angelica, weakly reduced these parameters, except for pouch fluid weight. The extract (30, 100 and 300 mg/kg) of cnidium significantly reduced these four parameters. The same doses of peony extract reduced carmine content, granuloma weight and pouch fluid weight, but less than those of the cnidium extract. The extract of cnidium and peony at the same doses reduced in an additive manner these inflammatory parameters in their combination. These results demonstrated that the Shimotsu-to extract reduced angiogenesis, granuloma formation, inflammatory cell migration and pouch fluid exudation in the adjuvant-induced chronic inflammation model. Cnidium represented the main ingredient for producing the anti-chronic inflammatory effects of Shimotsu-to extract. Cnidium and peony exhibited additive anti-inflammatory effects in combination.

Animals↗

PubMedDate not supplied

Soil ciliate species richness and abundance associated with the rhizosphere of different subtropical plant species.

Soil protozoa, and ciliates in particular, represent a microbial group abundant in the rhizosphere with an influential role on nutrient cycling. Under laboratory conditions, ciliates regulate the size and the composition of bacterial communities, and appear to stimulate ammonification and nitrification. In spite of their important ecological role, our understanding about the factors that control their diversity and abundance in natural forest ecosystems is still rudimentary. Plant species-specific interactions have been demonstrated between plants and soil bacteria and mycorrhizal fungi, due in part to the release of phytohormones and C- and N-rich exudates. We tested the hypothesis that the rhizosphere environments of different plant species also influence the species richness and abundance of soil ciliates. Plant effect, soil pH, moisture content, microbial biomass C, and inorganic nitrogen were measured among five plant species to determine the best predictor variables for soil ciliate species richness and total abundance in a subtropical moist forest in Puerto Rico. Based on an analysis of variance, we rejected the hypothesis that there was a plant species-specific effect on soil ciliates, unlike other microbial groups mentioned above. Using multiple regression analysis, we demonstrated that the flush of total inorganic nitrogen was the best predictor variable for both species richness and abundance of ciliates.

Animals↗

PubMed2000

Plants secrete substances that mimic bacterial N-acyl homoserine lactone signal activities and affect population density-dependent behaviors in associated bacteria.

In gram-negative bacteria, many important changes in gene expression and behavior are regulated in a population density-dependent fashion by N-acyl homoserine lactone (AHL) signal molecules. Exudates from pea (Pisum sativum) seedlings were found to contain several separable activities that mimicked AHL signals in well-characterized bacterial reporter strains, stimulating AHL-regulated behaviors in some strains while inhibiting such behaviors in others. The chemical nature of the active mimic compounds is currently unknown, but all extracted differently into organic solvents than common bacterial AHLs. Various species of higher plants in addition to pea were found to secrete AHL mimic activities. The AHL signal-mimic compounds could prove to be important in determining the outcome of interactions between higher plants and a diversity of pathogenic, symbiotic, and saprophytic bacteria.

4-Butyrolactone↗

PubMed2004

A proprietary extract from North American ginseng (Panax quinquefolium) enhances IL-2 and IFN-gamma productions in murine spleen cells induced by Con-A.

A patented aqueous extract from North American ginseng (Panax quinquefolium), containing mainly oligosaccharides and polysaccharides, is commercially available over the counter as COLD-FX (CVT-E002). This proprietary extract is used for the treatment of upper respiratory tract infections. Its in vitro stimulating effects on the immunoglobulin production by B lymphocytes and on natural immune responses by peritoneal exudates macrophages have been previously reported. Using C57 BL/6 mice, an ex vivo study was conducted to examine Con-A-induced splenocytic productions of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) as markers of acquired immune responses. CVT-E002 (10-500 microg/ml) significantly increased Con-A-induced IL-2 and IFN-gamma productions in spleen cells in a dose-dependent manner. Such response was seen by the ginseng extract originated from three different lots, suggesting consistency between the lots.

Adjuvants, Immunologic↗

PubMed2001

Temporal changes in the distribution and number of macrophage-lineage cells in the periodontal membrane of the rat molar in response to experimental tooth movement.

In order to evaluate the possible role of macrophages in the remodelling of periodontal tissue in response to tooth movement, temporal changes in the number and distribution of macrophage-lineage cells in the periodontal membrane of the rat molar tooth after experimental tooth movement were examined immunohistochemically using four anti-rat monoclonal antibodies: ED1 (anti-monocyte/macrophage-lineage cells and dendritic cells), ED2 (anti-resident macrophages), KI-M2R (anti-tissue macrophages), and OX6 (anti-class II molecules). The right maxillary first molar tooth of Wistar rats was moved mesially by a closed-coil spring for 1, 3, 5, or 7 days. Sham-treated rats wearing an inactivated appliance for each experimental period and entirely untreated rats were used as controls. Alternate horizontal serial cryostat sections were cut and incubated with antibodies to ED1, ED2, KI-M2R, and OX6. In addition, cells immunopositive for each monoclonal antibody in the periodontal membrane during tooth movement were analysed on the tension and pressure sides. In the control rats, large numbers of cells positively stained with each monoclonal antibody were distributed throughout the periodontal membrane surrounding the distobuccal root. At 1 day after experimental tooth movement, the number of immunopositive cells obtained with all four monoclonal antibodies decreased as compared with those of the control on the mesial/pressure side. During the later experimental time periods, ED1- and OX6-positive cells in the periodontal membrane of this side were significantly increased in number compared with controls, whereas the density and distribution pattern of cells positive with ED2 or KI-M2R remained unchanged. On the mesial/pressure side, which underwent hyalinization, a marked accumulation of OX6- and ED1-reactive cells, but not of ED2- or KI-M2R-reactive cells, was frequently observed in the area of the hyalinized tissue at 5-7 days after the start of tooth movement. On the distal/tension side, no particular change in the distribution of immunopositive cells obtained with any antibody was detected throughout the experimental periods, with the exception that there was a significant increase in the number of ED1-positive cells and in of OX6-positive cells at 1 and 7 days, respectively, after the start of tooth movement. These results suggest that after the start of tooth movement OX6- and ED1-positive cells, which are mostly exudative macrophages, but not ED2- and KI-M2R-positive cells, i.e., resident macrophages, may be actively engaged in bone resorption and the remodelling of tissues on the pressure side of the periodontal membrane.

Animals↗

PubMed1975

Physiological activity in mediastinal teratomata.

The clinical details of two patients with benign mediastinal teratomata are presented. Both patients developed inflammation of the root of the neck, the first after a small dose of radiotherapy and the second after a larger dose of radiotherapy and exploration of the thoracic inlet. In both cases, exploration of the inflamed area was followed by persistent discharge of fluid which was sterile on culture. In the first case, this was found to have a high cholesterol, lipid, and amylase content. In both cases, a benign mixed teratoma, with contents including intestinal epithelium and pancreatic tissue, was removed at thoracotomy. The suggestion is made that leakage of digestive enzymes from pancreatic, intestinal or salivary tissue may be a cause of inflammation in and around teratomata, especially after surgical exploration. Early thoracotomy is advised when the condition is recognized.

Adult↗

PubMed1981

An overview of periodontal surgical procedures.

It is obvious from the foregoing that there are many technical approaches to periodontal surgery. The mere presence of a periodontal pocket of a cerain depth as the major indicator for surgery is not as steadfast as once believed. Other criteria such as hemorrhage and exudate must also be used in evaluating the need for surgery. The decision on which approach to use remains with the therapist and the individual situation which he/she is faced. However, in the past decade it has become increasingly clear that the need for so-called more advanced surgical procedures is not as important to the control of periodontal diseases as was once thought. Regardless, it is also clear that some form of surgical intervention, as defined by this paper, is still necessary to interrupt the sequence of events that make up the pathogenesis of periodontal disease that leads to eventual tooth loss. This paper has reviewed and evaluated some of the current procedures available to the therapist in the surgical approach to therapy.

Alveoloplasty↗

PubMed1991

In vitro and in vivo replication for scanning electron microscopy of the cervical region of human teeth.

A replica technique for scanning electron microscopy (SEM) of the cervical region of human teeth was evaluated on extracted premolar teeth by comparing the replicas and the original specimens in the SEM. For in vivo application, the technique was modified to circumvent contamination by saliva and gingival exudate. Impressions were taken with an addition silicone polyvinylsiloxane material and the replicas were poured in epoxy resin die material. A surface active dentine conditioner facilitated flow of the impression material into irregular surface areas; in vivo a scavenger impression was used to remove surface debris. Custom trays were made of light-cured acrylic resin for the in vivo impressions. The method faithfully reproduced surface detail in the amelocemental region. In vivo the scavenger impression followed by application of the surface-active conditioner effectively cleaned the tooth surface. The custom tray allowed selection and inclusion of landmarks and ensured reproducibility. The method meets the requirements of a simple, reproducible, non-invasive means of documenting the micromorphology of the cervical region of the teeth.

Bicuspid↗

PubMed2003

Immunostimulating activity of the hot water-soluble polysaccharide extracts of Anacyclus pyrethrum, Alpinia galanga and Citrullus colocynthis.

Hot water polysaccharide extracts of Anacyclus pyrethrum (L.) Link. (family Compositae) Citrullus colocynthis (L.) Schrad. (family Cucurbitaceae) and Alpinia galanga (L.) Willd. (family Zingiberaceae) were tested for their immunostimulating activity in mice. The fractions from Anacyclus pyrethrum and Alpinia galanga showed a marked stimulating effect on the reticulo-endothelial system (RES) and increased the number of peritoneal exudate cells (PEC), and spleen cells of mice. In this case, the optimum doses were 50 and 25 mg/kg for the two fractions, respectively. On the other hand, the polysaccharide extracts of both Anacyclus pyrethrum and Alpinia galanga markedly enhanced the proliferation of the murine spleen cells in vitro using two tests (in vitro and in vivo effect). The results of the in vivo effect at a doses of 50 and 25 mg/kg, showed a stimulation index better than obtained with the in vitro effect at 50 and 25 microg/ml for Anacyclus pyrethrum and Alpinia galanga, respectively. While the extract of Citrullus colocynthis showed much weaker and variable immunostimulating activity.

Adjuvants, Immunologic↗

PubMed1996

Bradyrhizobium (Arachis) sp. strain NC92 contains two nodD genes involved in the repression of nodA and a nolA gene required for the efficient nodulation of host plants.

The common nodulation locus and closely linked nodulation genes of Bradyrhizobium (Arachis) sp. strain NC92 have been isolated on an 11.0-kb EcoRI restriction fragment. The nucleotide sequence of a 7.0-kb EcoRV-EcoRI subclone was determined and found to contain open reading frames (ORFs) homologous to the nodA, nodB, nodD1, nodD2, and nolA genes of Bradyrhizobium japonicum and Bradyrhizobium elkanii. Nodulation assays of nodD1, nodD2, or nolA deletion mutants on the host plants Macroptilium atropurpureum (siratro) and Vigna unguiculata (cowpea) indicate that nolA is required for efficient nodulation, as nolA mutants exhibit a 6-day nodulation delay and reduced nodule numbers. The nolA phenotype was complemented by providing the nolA ORF in trans, indicating that the phenotype is due to the lack of the nolA ORF. nodD1 mutants displayed a 2-day nodulation delay, whereas nodD2 strains were indistinguishable from the wild type. Translational nodA-lacZ, nodD1-lacZ, nodD2-lacZ, and nolA-lacZ fusions were created. Expression of the nodA-lacZ fusion was induced by the addition of peanut, cowpea, and siratro seed exudates and by the addition of the isoflavonoids genistein and daidzein. In a nodD1 or nodD2 background, basal expression of the nodA-lacZ fusion increased two- to threefold. The level of expression of the nodD2-lacZ and nolA-lacZ fusions was low in the wild type but increased in nodD1, nodD2, and nodD1 nodD2 backgrounds independently of the addition of the inducer genistein. nolA was required for increased expression of the nodD2-lacZ fusion. These data suggest that a common factor is involved in the regulation of nodD2 and nolA, and they are also consistent with a model of nod gene expression in Bradyrhizobium (Arachis) sp. strain NC92 in which negative regulation is mediated by the products of the nodD1 and nodD2 genes.

Acyltransferases↗

PubMedDate not supplied

Endoscopic examination and treatment of paranasal sinus disease in 16 horses.

Sixteen horses with suspected paranasal sinus disease had endoscopic examination of the paranasal sinuses with a 4.0 mm arthroscope either while standing and sedated (14 horses) or under general anesthesia (two horses). Endoscopic diagnosis included sinusitis (four horses), sinus cyst (three horses), hemorrhage (three horses), neoplasia (three horses), and tooth root abnormalities (two horses). No abnormalities were detected in one horse. Endoscopic findings concurred with the radiographic findings in 13 horses (81%). Samples of sinus contents for bacteriologic (eight horses) and histologic examinations (five horses) were obtained using sinus endoscopy. Diagnostic sinus endoscopy was combined with debridement, lavage, and suction as a therapeutic technique in 10 horses. In three horses, sinus exploration was performed after diagnostic endoscopy confirmed sinus disease, whereas in three horses, further therapy was not recommended after sinus endoscopy. Clinical signs of sinus disease resolved in 11 horses (69%) overall and in eight of 10 horses (80%) with sinusitis, cyst formation, or hemorrhage using endoscopic techniques alone. Mild, local subcutaneous emphysema occurred at the portal sites in all horses, but healing occurred without additional complications. Iatrogenic damage to sinus structures occurred in one horse. Sinus endoscopy was useful in the diagnosis and management of paranasal sinus disease and avoided the need for exploratory sinusotomy in some horses.

Animals↗

PubMed2006

Synthesis, transport and accumulation of quinolizidine alkaloids in Lupinus albus L. and L. angustifolius L.

Each of the principal quinolizidine alkaloids (QA) found in both xylem and phloem exudates together with extracts from all component organs collected from bitter (cv. Lupini) and sweet (cv. Ultra) cultivars of Lupinus albus L. were quantified by gas chromatographic analyses throughout reproductive development. In addition to establishing the major translocated QA species estimates for fluxes of QA to developing fruits based on their sap composition and water economy showed that around half of the QA that accumulated in fruit tissues was due to synthesis in situ and half to translocation principally by phloem. Detailed analyses of QA in transport fluids and component organs were extended to reciprocal homo- and hetero-grafts using bitter (cv. Fest) and sweet (cv. Danja) cultivars of L. angustifolius L. These data confirmed that the majority of QA were synthesized in shoot tissues. In both lupin species feeding and analysis of deuterated QA (lupanine and 13-hydroxylupanine) were used as tracers to demonstrate direct redistribution of alkaloids by translocation from mature leaves in phloem.

Alkaloids↗

PubMed1995

Inhibition of plasma extravasation by abruquinone A, a natural isoflavanquinone isolated from Abrus precatorius.

Polymyxin B-induced hind-paw edema was suppressed by abruquinone A, an isoflavanquinone isolated from Abrus precatorius, in normal as well in adrenalectomized mice. Unlike dexamethasone, abruquinone A did not increase the liver glycogen content in fasting adrenalectomized mice. The volume of exuded plasma was significantly reduced by abruquinone A in neurogenic inflammation, passive cutaneous anaphylactic reaction and compound 48/80-induced ear edema. Histamine-, serotonin-, bradykinin- and substance P-induced plasma extravasation in ear edema was also suppressed by abruquinone A. Abruquinone A, like isoproterenol, significantly reduced the bradykinin- and substance P-induced plasma extravasation in normal as well as in compound 48/80-pretreated mice. In addition, abruquinone A suppressed the bradykinin- and substance P-induced ear edema to a significantly greater extent than diphenhydramine/methysergide did. In the in vitro experiments, abruquinone A suppressed the compound 48/80-induced histamine and beta-glucuronidase released from isolated rat peritoneal mast cell preparations. These results suggest that the anti-inflammatory effect of abruquinone A is mediated partly via the suppression of the release of chemical mediators from mast cells and partly via the prevention of vascular permeability changes caused by mediators. The glucocorticoid activity and the release of glucocorticoid hormones from the adrenal gland are probably not involved.

Adrenalectomy↗