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Sample records for exudates and transudates

  1. The diagnostic value of pleural effusion ferritin and the ratio of it to serum ferritin in differentiating exudates from transudates

    To explore the diagnostic value of measuring the level of ferritin in pleural and peritoneal effusion for differentiating exudates from transudates, 128 effusion samples were initially detected for differentiating exudates from transudates by traditional method and Light's criteria. Ferritin in the effusions and serum ferritin were detected simultaneously, and the ratio of effusion ferritin (PFt) to serum ferritin (SFt) was counted. Based on the clinical data, the samples were divided into four groups and PFt and PFt/SFt were compared. At the same time, the sensitivity and specificity of PFt and PFt/SFt in differentiating exudates from transudates were compared with traditional method and Light's criteria. The results showed that in the groups of tuberculous pleurisy, non-tuberculous, benign pleurisy, and malignant tumor, the concentration of Ft in the effusions was significantly higher than that in the group of congestive heart failure and cirrhosis; and the Ft in exudates was significantly higher than that in transudates (P0.05). If the cut-off value was set up for Ft in the effusion as 100 μg/L and PFt/SFt ratio as 0.5, respectively, the differentiating sensitivity and specificity were 94.2% and 87.0%, respectively. Conclusion was that the concentration of PFt and PFt/SFt in exudates are higher than 100 μg/L and 0.5, respectively. On the contrary, they are lower than the cut-off level in transudates. PFt and PFt/SFt have high sensitivity and high specificity in differentiating exudates from transudates, and have great diagnostic value

  2. Pleural Effusion in Meigs' Syndrome-Transudate or Exudate?: Systematic Review of the Literature.

    Krenke, Rafal; Maskey-Warzechowska, Marta; Korczynski, Piotr; Zielinska-Krawczyk, Monika; Klimiuk, Joanna; Chazan, Ryszarda; Light, Richard W

    2015-12-01

    Although Meigs' syndrome is regarded as a well-defined entity, contradictory data on pleural fluid characteristics have been presented, with some papers classifying it as a transudate, whereas others stating that it is an exudate.The aims of the study were: (1) to evaluate pleural fluid characteristics in patients with Meigs' syndrome and (2) to analyze the prevalence of transudative and exudative pleural effusion in relation to the applied definition of the syndrome.We performed a search through medical databases (MEDLINE, EMBASE, SCOPUS, and GOOGLE SCHOLAR) to identify papers on Meigs' syndrome published between 1940 and 2013. Two authors independently reviewed each paper searching for prespecified data: (1) signs and symptoms, (2) tumor characteristics, (3) clinical and laboratory data on ascites, (4) clinical, radiological, and laboratory data on pleural fluid, (5) clinical course after tumor removal. All case reports were reclassified according to a new unequivocal classification of Meigs' syndrome-related entities.A total of 653 papers were initially identified, and 454 articles reporting 541 patients were included in the final analysis. After reclassification according to our case definitions, there were 196, 113, and 108 patients defined as classic Meigs' syndrome, nonclassic Meigs' syndrome, and pseudo-Meigs' syndrome, respectively. Significantly more patients presented with right-sided than left-sided and bilateral pleural effusions (P  3.0 g/dL was applied as a criterion of pleural exudate, 88.8% (80/90) of effusions were classified as exudates. Increasing the cut-off level to 3.5 g/dL resulted in only a modest decrease in the percentage of exudative effusions (81%, 73/90).Surprisingly few reports on Meigs' syndrome present data reliably defining the character of pleural effusion. The available data indicate, however, that the majority of pleural effusions in patients with this entity are exudates. This finding may be a prerequisite for the

  3. Lymphangitic Carcinomatosis as a Cause of Malignant Transient Pleural Transudate

    Raquel Garcia Sevila

    2009-01-01

    Full Text Available Although it is generally accepted that a malignant transient pleural transudate may appear during the early stages of lymphatic obstruction, cases demonstrating such probability are rare in literature. A 67-year-old woman was admitted to hospital because a lymphangitic carcinomatosis and a transudative infrapulmonary pleural effusion with a cytology positive for adenocarcinoma. One month later the effusion keeps being positive for adenocarcinoma but exudative in character. Lymphatic obstruction appears as the cause of the initial transudative characteristics of the pleural effusion.

  4. Dosagem de proteínas totais e desidrogenase lática para o diagnóstico de transudatos e exsudatos pleurais: redefinindo o critério clássico com uma nova abordagem estatística Determination of total proteins and lactate dehydrogenase for the diagnosis of pleural transudates and exudates: redefining the classical criterion with a new statistical approach

    Bernardo Henrique Ferraz Maranhão

    2010-08-01

    Full Text Available OBJETIVO: Propor um novo critério de classificação para a diferenciação entre exsudatos e transudatos pleurais através da dosagem de proteínas totais no líquido pleural (PT-LP e de desidrogenase lática no líquido pleural (DHL-LP exclusivamente, assim como comparar o rendimento diagnóstico entre esse novo critério com o critério clássico. MÉTODOS: Estudo observacional, transversal de tipo individualizado, no qual foram selecionados 181 pacientes com derrame pleural tratados em dois hospitais universitários no estado do Rio de Janeiro (RJ entre 2003 e 2006. Os parâmetros diagnósticos incluídos no critério clássico, assim como os do novo critério, foram determinados. RESULTADOS: Dos 181 pacientes, 152 e 29 foram diagnosticados, respectivamente, com exsudato pleural e transudato pleural. A sensibilidade, especificidade e acurácia do critério clássico para o diagnóstico de exsudato pleural foram, respectivamente, de 99,8%, 68,6% e 94,5%, enquanto, para o diagnóstico de transudato pleural, essas foram de 76,1%, 90,1% e 87,6%. Utilizando-se os pontos de corte de 3,4 g/dL para a dosagem de PT-LP e de 328,0 U/L para aquela de DHL-LP (novo critério, a sensibilidade, especificidade e acurácia foram de, respectivamente, 99,4%, 72,6% e 99,2%, para o diagnóstico de exsudato, e de 98,5%, 83,4% e 90,0%, para o diagnóstico de transudato. A acurácia do novo critério proposto para o diagnóstico de exsudato pleural foi significativamente maior que aquela do critério clássico (p = 0,0022. CONCLUSÕES: O rendimento diagnóstico dos dois critérios estudados foi semelhante. Portanto, esse novo critério de classificação pode ser utilizado na prática diária.OBJECTIVE: To propose a new classification criterion for the differentiation between pleural exudates and transudates-quantifying total proteins in pleural fluid (TP-PF and lactate dehydrogenase in pleural fluid (LDH-PF exclusively-as well as to compare this new criterion with

  5. Transudative Chylothorax in a Patient with Pulmonary Hypertension

    Sedat Kuleci

    2016-01-01

    Chylothorax, presence of chyle in the pleural space, is an infrequent clinical form of pleural effusion developed due to several pathologies, including pulmonary hypertension. Since now, very few clinical cases of transudative chylothorax due to pulmonary hypertension have been reported. In this report, we present a transudative chylothorax case of 70-year-old female patient with pulmonary hypertension due to cardiac valvular insufficiency and right heart failure.

  6. Transudative Chylothorax in a Patient with Pulmonary Hypertension

    Sedat Kuleci

    2016-02-01

    Full Text Available Chylothorax, presence of chyle in the pleural space, is an infrequent clinical form of pleural effusion developed due to several pathologies, including pulmonary hypertension. Since now, very few clinical cases of transudative chylothorax due to pulmonary hypertension have been reported. In this report, we present a transudative chylothorax case of 70-year-old female patient with pulmonary hypertension due to cardiac valvular insufficiency and right heart failure.

  7. Diagnostic value of Light's criteria and albumin gradient in classifying the pathophysiology of pleural effusion formation in cats.

    Zoia, Andrea; Drigo, Michele

    2016-08-01

    The primary aim of this study was to assess whether human Light's criteria with the cut-off values previously published for cats are useful and superior to the traditional veterinary classification in diagnosing pathophysiology of fluid formation in cats with pleural effusion. The secondary aim was to assess if the albumin gradient (ALBg) is a reliable criterion for differentiating exudates from transudates in patients with pleural effusion thought to be transudative by clinical criteria but identified as exudative by Light's criteria. Nineteen client-owned cats with pleural effusion were studied. The aetiology of the pleural effusion was used to establish the pathophysiology of its formation. Parameters measured or calculated undergoing statistical analysis included Light's criteria, total protein and total nucleated cell count in the pleural effusions, and the ALBg. Based on the pathophysiology of fluid formation there were seven transudates caused by increased hydrostatic pressure and 12 exudates. There was a significant difference in the accuracy of the Light's criteria in correctly classifying origin of the pleural fluid formation compared with the traditional veterinary classification (84% vs 53%). ALBg values were significantly different between transudates and exudates. One of the three transudates misclassified as exudates by Light's criteria was correctly identified as a transudate by the ALBg. In conclusion, pleural effusion should be classified as either a transudate or an exudate using Light's criteria. In cats with pleural effusion thought to be transudative by clinical criteria, but identified as exudative by Light's criteria, the ALBg may further help in correctly differentiating exudates from transudates. PMID:26116619

  8. Effect of smoking, abstention, and nicotine patch on epidermal healing and collagenase in skin transudate

    Sorensen, L.T.; Zillmer, R.; Agren, M.;

    2009-01-01

    Delayed wound healing may explain postoperative tissue and wound dehiscence in smokers, but the effects of smoking and smoking cessation on the cellular mechanisms remain unclear. Suction blisters were raised in 48 smokers and 30 never smokers. The fluid was retrieved and the epidermal roof was e...

  9. Effect of smoking, abstention, and nicotine patch on epidermal healing and collagenase in skin transudate.

    Sørensen, Lars Tue; Zillmer, Rikke; Agren, Magnus; Ladelund, Steen; Karlsmark, Tonny; Gottrup, Finn

    2009-01-01

    Delayed wound healing may explain postoperative tissue and wound dehiscence in smokers, but the effects of smoking and smoking cessation on the cellular mechanisms remain unclear. Suction blisters were raised in 48 smokers and 30 never smokers. The fluid was retrieved and the epidermal roof was excised. Transepidermal water loss (TEWL) was measured after 2, 4, and 7 days. Then, the smokers were randomized to continuous smoking or abstinence with a transdermal nicotine patch or a placebo by concealed allocation. The sequence was repeated after 4, 8, and 12 weeks in all smokers and abstainers and in 6 never smokers. Matrix metalloproteinase (MMP)-8 and MMP-1 levels in suction blister fluid were assessed by an enzyme-linked immunosorbent assay. Random-effects models for repeated measurements were applied and plevel was 21.2 ng/mL (6.6-43.0) (p=0.02, when compared with smokers). MMP-1 was unaffected by smoking and abstention. Transdermal nicotine patch did not affect any parameter. We conclude that smoking attenuates epidermal healing and may enhance extracellular matrix degradation. Three months of abstinence from smoking does not restore epidermal healing, whereas 4 weeks of abstinence normalizes suction blister MMP-8 levels. These findings suggest sustained impaired wound healing in smokers and potential reversibility of extracellular matrix degradation. PMID:19660042

  10. Effect of smoking, abstention, and nicotine patch on epidermal healing and collagenase in skin transudate

    Sørensen, Lars Tue; Zillmer, Rikke; Agren, Magnus; Ladelund, Steen; Karlsmark, Tonny; Gottrup, Finn

    2009-01-01

    Delayed wound healing may explain postoperative tissue and wound dehiscence in smokers, but the effects of smoking and smoking cessation on the cellular mechanisms remain unclear. Suction blisters were raised in 48 smokers and 30 never smokers. The fluid was retrieved and the epidermal roof was...... in 6 never smokers. Matrix metalloproteinase (MMP)-8 and MMP-1 levels in suction blister fluid were assessed by an enzyme-linked immunosorbent assay. Random-effects models for repeated measurements were applied and p< or =0.05 was considered significant. One week after wounding the TEWL was 17.20 (14...... of abstinence from smoking does not restore epidermal healing, whereas 4 weeks of abstinence normalizes suction blister MMP-8 levels. These findings suggest sustained impaired wound healing in smokers and potential reversibility of extracellular matrix degradation....

  11. Chickenpox Chorioretinitis with Retinal Exudates and Periphlebitis

    Hirokuni Kitamei

    2012-05-01

    Full Text Available Background: Chickenpox is rarely associated with posterior segment inflammation. We report on a case of unilateral chickenpox chorioretinitis with retinal exudates and periphlebitis. Case Presentation: A 21-year-old healthy man, who suffered from chickenpox 2 weeks prior to symptom development, exhibited mild anterior chamber cells, vitreous opacity, sheathing of retinal veins, and yellow-white exudates in his right eye. Varicella zoster virus DNA was detected by polymerase chain reaction in the aqueous humor. He was treated with intravenous acyclovir followed by oral prednisolone and valaciclovir. Aqueous cells quickly disappeared and retinal exudates diminished within 1 month, leaving faint retinal scarring. Retinal arteritis had never been observed in this patient. Conclusions: Although the ocular findings in this case were similar to acute retinal necrosis (ARN, the clinical features differed from ARN in the following points: (1 mild anterior chamber inflammation, (2 absence of retinal arteritis, and (3 prompt resolution of inflammatory findings. The distinctive clinical features indicated that chorioretinitis associated with chickenpox may not have the same pathological conditions as ARN.

  12. Retinoid-like activity and teratogenic effects of cyanobacterial exudates.

    Jonas, Adam; Buranova, Veronika; Scholz, Stefan; Fetter, Eva; Novakova, Katerina; Kohoutek, Jiri; Hilscherova, Klara

    2014-10-01

    Retinoic acids and their derivatives have been recently identified by chemical analyses in cyanobacteria and algae. Given the essential role of retinoids for vertebrate development this has raised concerns about a potential risk for vertebrates exposed to retinoids during cyanobacterial blooms. Our study focuses on extracellular compounds produced by phytoplankton cells (exudates). In order to address the capacity for the production of retinoids or compounds with retinoid-like activity we compared the exudates of ten cyanobacteria and algae using in vitro reporter gene assay. Exudates of three cyanobacterial species showed retinoid-like activity in the range of 269-2,265 ng retinoid equivalents (REQ)/L, while there was no detectable activity in exudates of the investigated algal species. The exudates of one green alga (Desmodesmus quadricaudus) and the two cyanobacterial species with greatest REQ levels, Microcystis aeruginosa and Cylindrospermopsis raciborskii, were selected for testing of the potential relation of retinoid-like activity to developmental toxicity in zebrafish embryos. The exudates of both cyanobacteria were indeed provoking diverse teratogenic effects (e.g. tail, spine and mouth deformation) and interference with growth in zebrafish embryos, while such effects were not observed for the alga. Fish embryos were also exposed to all-trans retinoic acid (ATRA) in a range equivalent to the REQ concentrations detected in exudates by in vitro bioassays. Both the phenotypes and effective concentrations of exudates corresponded to ATRA equivalents, supporting the hypothesis that the teratogenic effects of cyanobacterial exudates are likely to be associated with retinoid-like activity. The study documents that some cyanobacteria are able to produce and release retinoid-like compounds into the environment at concentrations equivalent to those causing teratogenicity in zebrafish. Hence, the characterization of retinoid-like and teratogenic potency should be

  13. Citrate Root Exudation under Zn and P Deficiency

    Bless Aplena Elen Siane

    2012-01-01

    Zinc and phosphorus are essential nutrients with low bioavailability in calcareous soils. Some plants exude organic acids to increase the solubility of these two nutrients. The objective of this study was to examine citrate exudation rates of different lupin (Feodora and Energy) and rapeseed (Dunkeld, Yickadee and Rainbow) cultivars underdeficiencies of Zn and P. The plants were cultivated into three different nutrient solutions (complete, -Zn, and -P)with pH around 7. Under Zn deficiency, ra...

  14. Field Evaluation of Calypte’s AWARE™ Blood Serum Plasma (BSP) and Oral Mucosal Transudate (OMT) Rapid Tests for Detecting Antibodies to HIV-1 and 2 in Plasma and Oral Fluid

    Alemnji, George A.; Ngulefac, Gisele A; Ndumbe, Peter M; Asonganyi, Tazoacha

    2009-01-01

    As programs to prevent and care for HIV-infected persons are scaled-up in Africa, there is the need for continuous evaluation of the performance of test kits that could best support these programs. The present study evaluated the sensitivity, specificity, ease of use, and cost of AWARE ™ Blood Serum Plasma (BSP) and Oral Mucosal Transudate (OMT) Rapid HIV-1/2 test kits using real-time and archived samples of HIV-infected persons from Cameroon. Matched whole blood and OMT specimens were collec...

  15. What is the Clinical Significance of Transudative Malignant Pleural Effusion?

    Ryu, Jeong-Seon; Ryu, Seong-Tae; Kim, Young-Shin; Cho, Jae-Hwa; Lee, Hong-Lyeol

    2003-01-01

    Background: A few reports of transudative malignant effusion on a small number of patients have suggested the need to perform routine cytologic examination in all cases of transudative pleural effusion, whether encountered for malignancy or not. The purpose of this study was to investigate whether cytologic examination should be performed in all cases of transudative pleural effusion for the diagnosis of malignancy. Methods: We performed a retrospective study of 229 consecutive patients with ...

  16. COMPARISION OF ADENOSINE DEAMINASE [ADA] LEVELS WITH CYTO-CHEMICAL ANALYSIS OF PLEURAL FLUIDS TO DIFFERENTIATE TUBERCULAR AND NON â TUBERCULAR EFFUSIONS

    Choukimath M Sharanabasav

    2013-12-01

    Full Text Available This study is intended to utilize biochemical parameters like ADA and protein levels in comparison with cell count and cell type in pleural fluid to differentiate tubercular and non-tubercular effusions. We have analyzed a total of 208 cases and among them 59.61% cases were ADA positive and 40.39% cases were ADA negative, and 156 cases were exudates and 52 cases were transudates. Categorized these effusions into 4 groups taking consideration of ADA, cell count, lymphocyte and protein levels as exudate with ADA positive, exudate with ADA negative, transudate with ADA positive and transudate with ADA negative. This study has shown promising results to diagnose tuberculosis with immediate and cost effectiveness that can be undertaken by any basic laboratory, in a endemic areas and developing countries like India

  17. Hard Retinal exudates and visual loss due to papilledema

    Rush, J.A.

    1982-02-01

    Bilateral papilledema developed in a patient with a cystic, grade 3 astrocytoma of the right frontal lobe. Despite successful neurosurgical treatment, /sup 60/Co radiotherapy, and oral corticosteroid therapy, progressive visual loss occurred. At examination one year later, visual activity was 20/200 and 20/70, and extensive lipid exudates in the peripapillary retina and central macula of each eye were noted. Retinal lipid exudates rarely complicate the course of surviving patients who had papilledema from intracranial tumor; physicians involved in the multispecialty care of such patients should be aware of the possible ocular residuals of persistent papilledema in an otherwise successfully treated patient.

  18. Citramalic acid and salicylic acid in sugar beet root exudates solubilize soil phosphorus

    Karlovsky Petr; Steingrobe Bernd; Ratzinger Astrid; Hettwer Ursula; Khorassani Reza; Claassen Norbert

    2011-01-01

    Abstract Background In soils with a low phosphorus (P) supply, sugar beet is known to intake more P than other species such as maize, wheat, or groundnut. We hypothesized that organic compounds exuded by sugar beet roots solubilize soil P and that this exudation is stimulated by P starvation. Results Root exudates were collected from plants grown in hydroponics under low- and high-P availability. Exudate components were separated by HPLC, ionized by electrospray, and detected by mass spectrom...

  19. Nature's amazing biopolymer: basic mechanical and hydrological properties of soil affected by plant exudates

    Naveed, Muhammad; Roose, Tiina; Raffan, Annette; George, Timothy; Bengough, Glyn; Brown, Lawrie; Keyes, Sam; Daly, Keith; Hallett, Paul

    2016-04-01

    Plant exudates are known to have a very large impact on soil physical properties through changes in mechanical and hydrological processes driven by long-chain polysaccharides and surface active compounds. Whilst these impacts are well known, the basic physical properties of these exudates have only been reported in a small number of studies. We present data for exudates obtained from barley roots and chia seeds, incorporating treatments examining biological decomposition of the exudates. When these exudates were added to a sandy loam soil, contact angle and drop penetration time increased exponentially with increasing exudate concentration. These wetting properties were strongly correlated with both exudate density and zero-shear viscosity, but not with exudate surface tension. Water holding capacity and water repellency of exudate mixed soil tremendously increased with exudate concentration, however they were significantly reduced on decomposition when measured after 14 days of incubation at 16C. Mechanical stability greatly increased with increasing exudate amendment to soils, which was assessed using a rheological amplitude sweep test near saturation, at -50 cm matric potential (field capacity) using indentation test, and at air-dry condition using the Brazilian test. This reflects that exudates not only attenuate plant water stress but also impart mechanical stability to the rhizosphere. These data are highly relevant to the understanding and modelling of rhizosphere development, which is the next phase of our research.

  20. Effectively managing wound exudate.

    Chamanga, Edwin

    2015-09-01

    The management of wound exudate remains a clinical challenge despite technological advances in products with better exudate-handling capacities. This clinical challenge is occasionally encountered when thick exudate (viscous exudate) is present, and when most modern dressings do not possess the capabilities to manage the viscosity while enabling exudate absorption. Maceration to the peri-wound area poses another challenge, irrespective of the number of topical barrier application products on the market and the innovation of dressing products that lock exudate away or those that encourage vertical wicking. In addition to all the above, in clinical practice, the assessment and documentation of wound exudate remains sporadic, leading to the challenges of effective wound exudate dressing selection and cost-effective dressings. PMID:26322408

  1. Chemical signatures of fossilized resins and recent plant exudates.

    Lambert, Joseph B; Santiago-Blay, Jorge A; Anderson, Ken B

    2008-01-01

    Amber is one of the few gemstones based on an organic structure. Found over most of the world, it is the fossil form of sticky plant exudates called resins. Investigation of amber by modern analytical techniques provides structural information and insight into the identity of the ancient plants that produced the source resin. Mass spectrometric analysis of materials separated by gas chromatography has identified specific compounds that are the basis of a reliable classification of the different types of amber. NMR spectroscopy of bulk, solid amber provides a complementary classification. NMR spectroscopy also can be used to characterize modern resins as well as other types of plant exudates such as gums, gum resins, and kinos, which strongly resemble resins in appearance but have very different molecular constitutions. PMID:18925589

  2. ACE/ACE2 Ratio and MMP-9 Activity as Potential Biomarkers in Tuberculous Pleural Effusions

    Wen-Yeh Hsieh, Tang-Ching Kuan, Kun-Shan Cheng, Yan-Chiou Liao, Mu-Yuan Chen, Pei-Heng Lin, Yuan-Chang Hsu, Chen-Yi Huang, Wei-Hua Hsu, Sheng-Yao Yu, Chih-Sheng Lin

    2012-01-01

    Full Text Available Objective: Pleural effusion is common problem, but the rapid and reliable diagnosis for specific pathogenic effusions are lacking. This study aimed to identify the diagnosis based on clinical variables to differentiate pleural tuberculous exudates from other pleural effusions. We also investigated the role of renin-angiotensin system (RAS and matrix metalloproteinase (MMPs in the pathogenesis of pleural exudates.Experimental design: The major components in RAS and extracellular matrix metabolism, including angiotensin converting enzyme (ACE, ACE2, MMP-2 and MMP-9 activities, were measured and compared in the patients with transudative (n = 45 and exudative (n = 80 effusions. The exudative effusions were come from the patients with tuberculosis (n = 20, pneumonia (n = 32, and adenocarcinoma (n = 28.Results: Increased ACE and equivalent ACE2 activities, resulting in a significantly increased ACE/ACE2 ratio in exudates, were detected compared to these values in transudates. MMP-9 activity in exudates was significantly higher than that in transudates. The significant correlation between ACE and ACE2 activity that was found in transudates was not found in exudates. Advanced analyses showed significantly increased ACE and MMP-9 activities, and decreased ACE2 activity in tuberculous pleural effusions compared with those in pneumonia and adenocarcinoma effusions. The results indicate that increased ACE and MMP-9 activities found in the exudates were mainly contributed from a higher level of both enzyme activities in the tuberculous pleural effusions.Conclusion: Interplay between ACE and ACE2, essential functions in the RAS, and abnormal regulation of MMP-9 probably play a pivotal role in the development of exudative effusions. Moreover, the ACE/ACE2 ratio combined with MMP-9 activity in pleural fluid may be potential biomarkers for diagnosing tuberculous pleurisy.

  3. ASSOCIATION BETWEEN RETINAL HARD EXUDATES AND DYSLIPIDEMIA IN TYPE 2 DIABETIC PATIENTS IN RURAL KARNATAKA

    Arun Kumar B.

    2015-10-01

    Full Text Available AIM: To evaluate the association of elevated serum lipids with retinal hard exudates in type 2 diabetic patients in rural Karnataka. MATERIAL AND METHODS : Hospital based cross sectional study which included 60 (n=60 type 2 diabetic patients (60 eyes fulfilling the inclusion criteria. Patients were subjected to detailed ocular examination, fundus examination done under full dilatation using indirect ophth almoscope with 20D lens and slit lamp biomicroscope with 90D lens. Fundus photographs were obtained using fundus camera. Grading of retinal hard exudates performed by utilizing modified Airlie House classification. The modified Airlie House Classification used is as follows: Grade 0 - No evidence of hard exudates; Grade 1 : Questionable hard exudates present; Grade 2 : Hard exudates less than standard photograph 3; Grade 3 : Hard exudates greater than or equal to standard photograph 3, but less than standard p hotograph 5; Grade 4 : Hard exudates greater than or equal to standard photograph 5, but less than standard photograph 4 and Grade 5 : Hard exudates greater than or equal to standard photograph 4. These grades were further divided into three groups of patie nt severity as follows: Group 1 (absent or minimal hard exudates included patients with Grade 0, 1 or 2 hard exudates; Group 2 (hard exudates present included patients with Grade 3 or 4 hard exudates and Group 3 (prominent hard exudates included patient s with Grade 5 hard exudates. Fasting lipid profile including serum total cholesterol, low density lipoproteins, very low density lipoproteins, high density lipoproteins and triglycerides was obtained. Association of dyslipidemia with retinal hard exudates was analysed using one way ANOVA test. RESULTS: On statistical analysis with ANOVA test retinal hard exudates were significantly associated with elevated total cholesterol (p= .0001, triglycerides (p= .0001, serum LDL (p=.008, serum VLDL (p=.012, and negative correlation was found

  4. Chemical and spectroscopic studies of Cercidium praecox gum exudate.

    León de Pinto, G; Martínez, M; Rivas, C

    1994-07-01

    The structure of the polysaccharide from Cercidium praecox (R&P) Harms gum exudate has been studied by Smith degradation, by sugar and methylation analyses, and by 13C NMR spectroscopy. The results showed a (1-->4)-xylan core. Some xylose residues are substituted at O-2 by alpha-D-glucuronic acid and 4-O-methyl-alpha-D-glucuronic acid residues. beta-D-Glucuronic acid is present, probably as terminal residues. The arabinose is present as alpha-L-furanose and beta-L-pyranose. PMID:8062287

  5. Combined intravitreal bevacizumab with phacoemulsification in visually significant cataract and visually significant exudative maculopathy

    Ahmad Mansour; Bashshur, Ziad F.; Sibai, Tarek A.; Abla Mehio-Sibai; Hamam, Rola N.

    2011-01-01

    Purpose : We investigated the visual outcome of combined phacoemulsification with intravitreal bevacizumab, in eyes with dense cataract and visually significant exudative maculopathy. Materials and Methods : Prospective longitudinal pilot study of consecutive patients treated by two surgeons in 2006, using intravitreal bevacizumab at the end of phacoemulsification. The historical control group consisted of consecutive subjects with exudative maculopathy and dense cataract treated by the s...

  6. Bioavailability of zinc and phosphorus in calcareous soils as affected by citrate exudation

    Duffner, A.; Hoffland, E.; Temminghoff, E.J.M.

    2012-01-01

    Aims Zinc (Zn) and phosphorus (P) deficiency often occurs at the same time and limits crop production in many soils. It has been suggested that citrate root exudation is a response of plants to both deficiencies. We used white lupin (Lupinus albus L.) as a model plant to clarify if citrate exuded by

  7. The regulation of gelation of Phloem exudate from cucurbita fruit by dilution, glutathione, and glutathione reductase.

    Alosi, M C; Melroy, D L; Park, R B

    1988-04-01

    The average glutathione equivalent concentration in phloem exudate collected from squash fruit (Cucurbita moschata [Duchesne] Poir. var Butternut) and pumpkin fruit (Cucurbita pepo [L.] var Jack-o-lattern) was 1.02 and 0.60 millimolar, respectively. Glutathione reductase (EC 1.6.4.2) activity in phloem exudate from squash and pumpkin fruit averaged 0.48 and 1.74 micromole NADPH oxidized per minute per milliliter, respectively. Protein concentrations in fruit phloem exudates averaged 67 milligrams per milliliter for squash and 57 milligrams per milliliter for pumpkin. The phloem-specific P-proteins account for most of the protein content of exudate. Pure exudate from fruit does not gel for hours or days, but when diluted with neutral or alkaline aqueous solutions, exudate gels rapidly. Exudate solutions undergo biphasic pH changes with dilution. We suggest that P-protein undergoes conformational change upon dilution, exposing titratable groups and sulfhydryl residues. Oxidation of the latter forms the intermolecular disulfide bridges of the gel. The gelation of diluted exudate is regulated by factors (oxygen, pH, glutathione, NADPH) which affect the maintenance of reduced sulfhydryl residues and the activity of glutathione reductase. While these factors may also act in vivo to regulate redox conditions in phloem, their relationship to hypothetical sol/gel transitions or motile and nonmotile phases in the transport conduit is unknown. PMID:16666036

  8. The effects of cotton root exudates on the growth and development of Verticillium dahliae

    Yuxiang WU; Weiping FANG; Shuijin ZHU; Kuiying JIN; Daofan JI

    2008-01-01

    The effects of upland cotton root exudates on the growth and development of Verticillium dahliae were studied, through the compared analysis of the root exudates components between the resistant and suscept-ive cotton materials, using a pair of resistant and sus-ceptive isogenic lines to Verticillium wilt, Z5629 and Z421, as well as 4 other upland cotton cultivars with different resistant levels of Verticillium wilt. The results showed that the amino acids in the root exudates of the resistant cultivars were much less than that of the sus-ceptible ones. Compared with the susceptible ones, there were a lack of aspartic acid, threonine, glutamic acid, alanine, isoleucine, leucine, phenylalanine, lysine and proline in the root exudates from the resistant cul-tivars. On the contrary, arginine was lacking in the sus-ceptive cultivars. The saccharide types in the root exudates were no different between the two kinds of cultivars, but the contents of glucose, fructose and suc-rose in the root exudates of the susceptible varieties were much higher than those in the resistant ones. The experiment of Verticillium dahliae culture showed that the cotton root exudates from resistant cultivars can effectively restrain the spore germination and mycelium growth of Verticillium dahliae, and the argi-nine was the leading amino acid in this inhibitory action, besides the nutrition of the root exudates. However, the cotton root exudates from the susceptive cotton cultivars can improve the growth and develop-ment of Verticillium dahliae effectively; among the amino acid in the exudates, alanine was the most active one in this stimulating function.

  9. Bioassay and Identification of Root Exudates of Three Fruit Tree Species

    Jiang-Hong Zhang; Zhi-Quan Mao; Li-Qin Wang; Huai-Rui Shu

    2007-01-01

    A laboratory bioassay was designed to determine the allelopathic potential of root exudates of three fruit tree species on apple germination. The results showed that root exudates of apple (Malus pumila L.) and peach (Prunus persica L.), each at concentrations of 0.02 and 0.2 mg/L, inhibited germination and radicle growth of apple seeds by 56.7%, 60.7%, 51.5%, and 59.3%, respectively. The corresponding shoot growth inhibition rate was 49.5%, 46.7%, 36.4%, and 44%, respectively. Root exudates of jujube (Ziziphus jujuba Mill.) had no significant effect on apple seeds.Qualitative determination of root exudates of apple, peach, and jujube tree was developed with gas chromatography-mass spectrometry. The root exudates of apple seedlings mainly contain organic acids, glycol, esters, and benzenphenol derivatives. Peach root exudates contained phenolic acids and benzenphenol derivatives in addition to two unidentified compounds. The root exudates of jujube did not contain any phenolic acids.

  10. The root exudation of grain amaranth and its role in release of mineral potassium

    Grain amaranth is a pseudo-cereal with big biomass and abundant mineral elements. The genotypic variations of Amaranthus spp. with different K-use efficiency (KUE) were studied in root exudation and the role of root exudate in solubilizing mineral K by use of hydroponics and 14C tracing technique. The results showed that high KUE varieties had strong ability of both CO2 assimilation and exudation of photosynthate. Predominate low-molecular-weight organic acids (IMWOAs) in root exudate of grain amaranth was oxalic acid, accounting for more than 95% of the total LMWOAs tested. Amaranthus spp. differed in the intensity of root exudation with an order as. A. dubis>A. retroflexus>A. cruentus. In the same species, then, high KUE varieties usually had higher power of excretion. K-free treatment promoted excretion of photosynthate, but oxalic acid increased only in high KUE varieties. The root exudate could solubilize K-minerals significantly, and the amount of oxalic acid and its K release were closely correlated, which indicated that oxalic acid exudation is one of the key mechanism for Amaranthus spp. to enrich and take up K from K-minerals

  11. Rheological Modeling and Characterization of Ficus platyphylla Gum Exudates

    Nnabuk O. Eddy

    2013-01-01

    Full Text Available Ficus platyphylla gum exudates (FP gum have been analyzed for their physicochemical parameters and found to be ionic, mildly acidic, odourless, and yellowish brown in colour. The gum is soluble in water, sparingly soluble in ethanol, and insoluble in acetone and chloroform. The nitrogen (0.39% and protein (2.44% contents of the gum are relatively low. The concentrations of the cations were found to increase according to the following trend, Mn>Fe>Zn>Pb>Cu>Mg>Cd>Ca. Analysis of the FTIR spectrum of the gum revealed vibrations similar to those found in polysaccharides while the scanning electron micrograph indicated that the gum has irregular molecular shapes, arranged randomly. The intrinsic viscosity of FP gum estimated by extrapolating to zero concentrations in Huggins, Kraemer, Schulz-Blaschke, and Martin plots has an average value of 7 dL/g. From the plots of viscosity versus shear rate/speed of rotation and also that of shear stress versus shear rate, FP gum can be classified as a non-Newtonian gum with characteristics-plastic properties. Development of the Master_s curve for FP gum also indicated that the gum prefers to remain in a dilute domain (Cand indicated the presence of fewer inter- and intramolecular interactions.

  12. Familial Exudative Vitreoretinopathy: Follow-Up and Treatment Results

    Zafer Cebeci

    2014-10-01

    Full Text Available Objectives: To report the follow-up and treatment results of cases with the diagnosis of familial exudative vitreoretinopathy (FEVR in our clinic. Materials and Methods: We retrospectively reviewed the records of 19 eyes of 10 cases of FEVR that were followed up and some of them were treated in our clinic. Results: Nine male and one female patients with a mean age of 10.1 (3-30 years were included in the study. Seven patients had a family history of FEVR. Twelve eyes of 8 patients had laser photocoagulation to peripheral avascular areas, 3 patients had vitreoretinal surgery on one of their eyes three times. Unilateral total retinal detachment was determined in two patients at the initial visit and in three patients at the follow-up visits; because no improvement in the vision was expected, surgery was not done. Conclusion: FEVR is an inherited disease that can be detected in any age and can cause severe vision loss. These patients should be followed up throughout the life, and the essential treatment at the appropriate time can lead to partial visual recovery. (Turk J Ophthalmol 2014; 44: 370-3

  13. A critical review of modern and emerging absorbent dressings used to treat exuding wounds.

    Sweeney, India R; Miraftab, Mohsen; Collyer, Graham

    2012-12-01

    Wound management has progressed significantly over the last five decades. This emanates from a greater understanding of wound healing, technological progression and improved clinical and scientific research. There are currently a plethora of absorbent dressings on the wound care market which claim to have the ability to manage exudates whilst encouraging healing. However, it is becoming clear, from analysing randomised controlled trials, that some of these absorbent dressings are not meeting their expectations when applied in a clinical setting. Many clinicians now feel that there should be more focus, not only on a dressing's ability to manage exudate efficiently, but on a dressing's ability to proactively encourage healing and thus exudate reduction will ensue. This paper proposes to critically review modern and emerging absorbent wound care dressings used to manage exuding wounds and discuses some advances in this area. PMID:22248337

  14. Atypical presentation of ocular toxoplasmosis: A Case report of exudative retinal detachment and choroidal Ischemia

    Yahya A Al-Zahrani

    2016-01-01

    Full Text Available A 24-year-old healthy male presented with a chief complaint of blurred vision in the right eye for 1-week. Fundus examination indicated right exudative retinal detachment and choroidal ischemia. The patient responded well to anti-toxoplasmosis medications and steroids. Exudative retinal detachment and choroidal ischemia are atypical presentations of ocular toxoplasmosis. However, both conditions responded well to anti.parasitic therapy with steroid.

  15. Citramalic acid and salicylic acid in sugar beet root exudates solubilize soil phosphorus

    Karlovsky Petr

    2011-08-01

    Full Text Available Abstract Background In soils with a low phosphorus (P supply, sugar beet is known to intake more P than other species such as maize, wheat, or groundnut. We hypothesized that organic compounds exuded by sugar beet roots solubilize soil P and that this exudation is stimulated by P starvation. Results Root exudates were collected from plants grown in hydroponics under low- and high-P availability. Exudate components were separated by HPLC, ionized by electrospray, and detected by mass spectrometry in the range of mass-to-charge ratio (m/z from 100 to 1000. Eight mass spectrometric signals were enhanced at least 5-fold by low P availability at all harvest times. Among these signals, negative ions with an m/z of 137 and 147 were shown to originate from salicylic acid and citramalic acid. The ability of both compounds to mobilize soil P was demonstrated by incubation of pure substances with Oxisol soil fertilized with calcium phosphate. Conclusions Root exudates of sugar beet contain salicylic acid and citramalic acid, the latter of which has rarely been detected in plants so far. Both metabolites solubilize soil P and their exudation by roots is stimulated by P deficiency. These results provide the first assignment of a biological function to citramalic acid of plant origin.

  16. Stress differentially impacts reserve pools and root exudation: implications for ecosystem functioning and carbon balance

    Landhäusser, Simon; Karst, Justine; Wiley, Erin; Gaster, Jacob

    2016-04-01

    Environmental stress can influence carbon assimilation and the accumulation and distribution of carbon between growth, reserves, and exudation; however, it is unclear how these processes vary by different stress types. Partitioning of carbon to growth and reserves in plants might also vary between different organs. Roots reserves are of particular interest as they link the plant with the soil carbon cycle through exudation. Simple models of diffusion across concentration gradients predict the more C reserves in roots, the more C should be exuded from roots. However, the mechanisms underlying the accumulation and loss of C from roots may differ depending on the stress experienced by the plants. In a controlled study we tested whether different types of stresses (shade, cold soil, and drought) have differential effects on the distribution, abundance, and form (sugar vs. starch) of carbohydrates in seedlings, and whether these changes alone could explain differences in root exudation between stress types. Non-structural carbohydrate (NSC) concentration and pool sizes varied by stress type and between organs. Mass-specific C exudation increased with fine root sugar concentration; however, stress type affected exudation independently of reserve concentration. Seedlings exposed to cold soils exuded the most C on a per root mass basis followed by shade and drought. Through 13C labeling, we also found that depending on the stress type, aspen seedlings may be less able to control the loss of C to the soil compared with unstressed seedlings, resulting in more C leaked to the rhizosphere. The loss of C beyond that predicted by simple concentration gradients might have important implications for ecosystem functioning and carbon balance. If stressed plants lose proportionally more carbon to the soil, existing interactions between plants and soils may decouple under stress, and may include unexpected C fluxes between trees, soils and the atmosphere with a changing climate.

  17. Antitumor activity of fermented noni exudates and its fractions.

    Li, Jinhua; Chang, Leng-Chee; Wall, Marisa; Wong, D K W; Yu, Xianzhong; Wei, Yanzhang

    2013-01-01

    Noni has been extensively used in folk medicine by Polynesians for over 2000 year. Recent studies have shown that noni has a wide spectrum of therapeutic activities including inhibition of angiogenesis, anti-inflammatory effects and anti-cancer activities. Intraperitoneal (i.p.) injection of fermented noni exudates (fNE) were previously found to induce significant tumor rejection in a S180 mouse sarcoma tumor model, while natural killer (NK) cells were demonstrated to be markedly involved in fNE-induced antitumor activity. In this study, fNE was partitioned into three fractions and their antitumor effects were examined using i.p. injection or as water supplement. The in vivo animal study results showed that when delivered by i.p. injection, n-butanol fraction of fNE (BuOH) effectively rejected (100%) tumor challenge and eradicated existing tumors (75%). When delivered as a water supplement, 62.5% of the mice receiving the n-butanol or ethyl acetate fractions resisted tumor cells. The tumor-resistant mice effectively rejected more and higher doses of tumor challenge, indicating that the immune system was activated. The findings confirm those of an earlier study showing fNE to have anti-tumor activity and demonstrating that the n-butanol fraction of fNE contains active antitumor components, to be further identified. More importantly, the antitumor effect of fNE and its fractions as water supplements renders a significant potential for identifying novel and powerful new dietary products for cancer prevention. PMID:24649140

  18. A multi-step system for screening and localization of hard exudates in retinal images

    Bopardikar, Ajit S.; Bhola, Vishal; Raghavendra, B. S.; Narayanan, Rangavittal

    2012-03-01

    The number of people being affected by Diabetes mellitus worldwide is increasing at an alarming rate. Monitoring of the diabetic condition and its effects on the human body are therefore of great importance. Of particular interest is diabetic retinopathy (DR) which is a result of prolonged, unchecked diabetes and affects the visual system. DR is a leading cause of blindness throughout the world. At any point of time 25 - 44% of people with diabetes are afflicted by DR. Automation of the screening and monitoring process for DR is therefore essential for efficient utilization of healthcare resources and optimizing treatment of the affected individuals. Such automation would use retinal images and detect the presence of specific artifacts such as hard exudates, hemorrhages and soft exudates (that may appear in the image) to gauge the severity of DR. In this paper, we focus on the detection of hard exudates. We propose a two step system that consists of a screening step that classifies retinal images as normal or abnormal based on the presence of hard exudates and a detection stage that localizes these artifacts in an abnormal retinal image. The proposed screening step automatically detects the presence of hard exudates with a high sensitivity and positive predictive value (PPV ). The detection/localization step uses a k-means based clustering approach to localize hard exudates in the retinal image. Suitable feature vectors are chosen based on their ability to isolate hard exudates while minimizing false detections. The algorithm was tested on a benchmark dataset (DIARETDB1) and was seen to provide a superior performance compared to existing methods. The two-step process described in this paper can be embedded in a tele-ophthalmology system to aid with speedy detection and diagnosis of the severity of DR.

  19. Rhizosphere water dynamics: role of exudates in mediating water retention and flow characteristics

    Albalasmeh, Ammar; Ghezzehei, Teamrat

    2013-04-01

    In recent years, significant amount of literature showed that rhizosphere's physical and chemical properties markedly differ from those of the bulk soil. Plants invest large portion of their photosynthetic carbon in developing root architecture that optimally exploits water and nutrient distributions in the soil. There is indirect evidence suggesting that these exudates play a major role in altering the of the soil water retention properties. In this study, we investigated the role of root exudates on rhizosphere water dynamics using analog system. Glass beads were used to represent loose soil and dilute solutions of polygalacutronic acid (PGA) to mimic exudates (0, 1, 5, 15 and 29 g/L). The samples were subjected to periods of drying and subsequent equilibration. At each stage, the water potential was measured using WP4C Dewpoint PotentiaMeter. On the other hand, sand samples were saturated with PGA at the same concentration used to study the effect of exudates on water evaporation rate. The effect of root exudates on soil water retention can be attributed to at least two factors. The most widely speculated effect is through enhanced of soil aggregation. This effect is primarily due to capillary adhesion in fine pores within aggregates and is consistent with visual observation of pronounced aggregation in many rhizosphere soils. The second factor is related to osmotic effect of the exudate solution. Our observations show that the capillary effect is mostly limited to higher water potential regime (> -1 bar suction). Whereas the osmotic effect dominates in <- 1 bar suction. At the same time, the osmotic potential results from these organic exudates play an important role in reducing the evaporation rate. These results will provide direct quantitative evidence of how rhizosphere organic matter helps plant-soil relations.

  20. Root exudates of wetland plants influenced by nutrient status and types of plant cultivation.

    Wu, Fu Yong; Chung, Anna King Chuen; Tam, Nora Fung Yee; Wong, Ming Hung

    2012-07-01

    The present study investigated the amounts of root exudates and composition of organic acids released from two wetland plants (Typha latifolia and Vetiver zizanioides) under two nutrient treatments: low level (0.786 mM N and 0.032 mM P) and high level (7.86 mM N and 0.32 mM P) and two types of plant cultivation: monoculture and co-culture of the two plants. Low nutrient treatment significantly (p < 0.05) increased the root exudates of T. latifolia during the initial growth period (1-21 d) and those of V. zizanioides and the co-culture during the whole growth period. The concentrations of dissolved organic carbon in the root exudates of the co-culture in the low nutrient treatment were 3.23-7.91 times of those in the high nutrient treatment during the medium growth period (7-28 d). The compositions of organic acids varied between the two plant species and between the two nutrient treatments. The pattern of organic acids was also different between the co-culture and the monoculture. Oxalic acid was by far the major organic acid exuded from the two wetland plants. The present study on root exudates suggests that co-culture of wetland plant species would be more useful in the reclamation of waste water than a monoculture system. PMID:22908625

  1. Organic acid exudation from the roots of Cunninghamia lanceolata and Pinus massoniana seedlings under low phosphorus stress

    Yuanchun YU; Jian YU; Qihua SHAN; Li FANG; Defeng JIANG

    2008-01-01

    Organic acid exudation from the roots of Chinese fir (Cunninghamia lanceolata) and Masson pine (Pinus massoniana) seedlings under low phosphorus stress was studied using the solution culture method. The results revealed that organic acid exudation from the roots of Chinese fir and Masson pine seedlings under low phosphorus stress increased. Compared with P3 (KH2PO4, 0.5 mmol/L), the average organic acid exuda-tion from the root of Masson pine seedlings under P0 (KH2PO4, 0 mmol/L), P1 (KH2PO4, 0.03 mmol/L) and P2(KH2PO4, 0.09 mmol/L) increased by 328.6%, 267.9% and 126.4% respectively. Masson pine from Zhejiang Province in China had the highest organic acid exuda-tion. Under low phosphorus stress, the increase in organic acid exudation from the different provinces of Chinese fir and Masson pine varied. Masson pine from Zhejiang Province mainly increased oxalic acid, tartaric acid, citric acid and malic acid exudation, that from Guangxi Province mainly increased oxalic acid and tartaric acid exudation, and that from Guizhou Province, China mainly increased oxalic acid, tartaric acid and malic acid exudation. Chinese fir mainly increased oxalic acid and tartaric acid exudation.

  2. Methylobacterium-plant interaction genes regulated by plant exudate and quorum sensing molecules

    Manuella Nóbrega Dourado

    2013-12-01

    Full Text Available Bacteria from the genus Methylobacterium interact symbiotically (endophytically and epiphytically with different plant species. These interactions can promote plant growth or induce systemic resistance, increasing plant fitness. The plant colonization is guided by molecular communication between bacteria-bacteria and bacteria-plants, where the bacteria recognize specific exuded compounds by other bacteria (e.g. homoserine molecules and/or by the plant roots (e.g. flavonoids, ethanol and methanol, respectively. In this context, the aim of this study was to evaluate the effect of quorum sensing molecules (N-acyl-homoserine lactones and plant exudates (including ethanol in the expression of a series of bacterial genes involved in Methylobacterium-plant interaction. The selected genes are related to bacterial metabolism (mxaF, adaptation to stressful environment (crtI, phoU and sss, to interactions with plant metabolism compounds (acdS and pathogenicity (patatin and phoU. Under in vitro conditions, our results showed the differential expression of some important genes related to metabolism, stress and pathogenesis, thereby AHL molecules up-regulate all tested genes, except phoU, while plant exudates induce only mxaF gene expression. In the presence of plant exudates there is a lower bacterial density (due the endophytic and epiphytic colonization, which produce less AHL, leading to down regulation of genes when compared to the control. Therefore, bacterial density, more than plant exudate, influences the expression of genes related to plant-bacteria interaction.

  3. Methylobacterium-plant interaction genes regulated by plant exudate and quorum sensing molecules.

    Dourado, Manuella Nóbrega; Bogas, Andrea Cristina; Pomini, Armando M; Andreote, Fernando Dini; Quecine, Maria Carolina; Marsaioli, Anita J; Araújo, Welington Luiz

    2013-12-01

    Bacteria from the genus Methylobacterium interact symbiotically (endophytically and epiphytically) with different plant species. These interactions can promote plant growth or induce systemic resistance, increasing plant fitness. The plant colonization is guided by molecular communication between bacteria-bacteria and bacteria-plants, where the bacteria recognize specific exuded compounds by other bacteria (e.g. homoserine molecules) and/or by the plant roots (e.g. flavonoids, ethanol and methanol), respectively. In this context, the aim of this study was to evaluate the effect of quorum sensing molecules (N-acyl-homoserine lactones) and plant exudates (including ethanol) in the expression of a series of bacterial genes involved in Methylobacterium-plant interaction. The selected genes are related to bacterial metabolism (mxaF), adaptation to stressful environment (crtI, phoU and sss), to interactions with plant metabolism compounds (acdS) and pathogenicity (patatin and phoU). Under in vitro conditions, our results showed the differential expression of some important genes related to metabolism, stress and pathogenesis, thereby AHL molecules up-regulate all tested genes, except phoU, while plant exudates induce only mxaF gene expression. In the presence of plant exudates there is a lower bacterial density (due the endophytic and epiphytic colonization), which produce less AHL, leading to down regulation of genes when compared to the control. Therefore, bacterial density, more than plant exudate, influences the expression of genes related to plant-bacteria interaction. PMID:24688531

  4. Tall fescue cultivar and fungal endophyte combinations influence plant growth and root exudate composition.

    Guo, Jingqi; McCulley, Rebecca L; McNear, David H

    2015-01-01

    Tall fescue [Lolium arundinaceum (Schreb.)] is a cool-season perennial grass used in pastures throughout the Southeastern United States. The grass can harbor a shoot-specific fungal endophyte (Epichloë coenophiala) thought to provide the plant with enhanced resistance to biotic and abiotic stresses. Because alkaloids produced by the common variety of the endophyte cause severe animal health issues, focus has been on replacing the common-toxic strain with novel varieties that do not produce the mammal-toxic alkaloids but maintain abiotic and biotic stress tolerance benefits. Little attention has been given to the influence of the plant-fungal symbiosis on rhizosphere processes. Therefore, our objective was to study the influence of this relationship on plant biomass production and root exudate composition in tall fescue cultivars PDF and 97TF1, which were either not infected with the endophyte (E-), infected with the common toxic endophyte (CTE+) strain or with one of two novel endophytes (AR542E+, AR584E+). Plants were grown sterile for 3 weeks after which plant biomass, total organic carbon, total phenolic content and detailed chemical composition of root exudates were determined. Plant biomass production and exudate phenolic and organic carbon content were influenced by endophyte status, tall fescue cultivar, and their interaction. GC-TOF MS identified 132 compounds, including lipids, carbohydrates and carboxylic acids. Cluster analysis showed that the interaction between endophyte and cultivar resulted in unique exudate profiles. This is the first detailed study to assess how endophyte infection, notably with novel endophytes, and tall fescue cultivar interact to influence root exudate composition. Our results illustrate that tall fescue cultivar and endophyte status can influence plant growth and root exudate composition, which may help explain the observed influence of this symbiosis on rhizosphere biogeochemical processes. PMID:25914697

  5. CAD scheme for detection of hemorrhages and exudates in ocular fundus images

    Hatanaka, Yuji; Nakagawa, Toshiaki; Hayashi, Yoshinori; Mizukusa, Yutaka; Fujita, Akihiro; Kakogawa, Masakatsu; Kawase, Kazuhide; Hara, Takeshi; Fujita, Hiroshi

    2007-03-01

    This paper describes a method for detecting hemorrhages and exudates in ocular fundus images. The detection of hemorrhages and exudates is important in order to diagnose diabetic retinopathy. Diabetic retinopathy is one of the most significant factors contributing to blindness, and early detection and treatment are important. In this study, hemorrhages and exudates were automatically detected in fundus images without using fluorescein angiograms. Subsequently, the blood vessel regions incorrectly detected as hemorrhages were eliminated by first examining the structure of the blood vessels and then evaluating the length-to-width ratio. Finally, the false positives were eliminated by checking the following features extracted from candidate images: the number of pixels, contrast, 13 features calculated from the co-occurrence matrix, two features based on gray-level difference statistics, and two features calculated from the extrema method. The sensitivity of detecting hemorrhages in the fundus images was 85% and that of detecting exudates was 77%. Our fully automated scheme could accurately detect hemorrhages and exudates.

  6. Natural variation of root exudates in Arabidopsis thaliana-linking metabolomic and genomic data.

    Mönchgesang, Susann; Strehmel, Nadine; Schmidt, Stephan; Westphal, Lore; Taruttis, Franziska; Müller, Erik; Herklotz, Siska; Neumann, Steffen; Scheel, Dierk

    2016-01-01

    Many metabolomics studies focus on aboveground parts of the plant, while metabolism within roots and the chemical composition of the rhizosphere, as influenced by exudation, are not deeply investigated. In this study, we analysed exudate metabolic patterns of Arabidopsis thaliana and their variation in genetically diverse accessions. For this project, we used the 19 parental accessions of the Arabidopsis MAGIC collection. Plants were grown in a hydroponic system, their exudates were harvested before bolting and subjected to UPLC/ESI-QTOF-MS analysis. Metabolite profiles were analysed together with the genome sequence information. Our study uncovered distinct metabolite profiles for root exudates of the 19 accessions. Hierarchical clustering revealed similarities in the exudate metabolite profiles, which were partly reflected by the genetic distances. An association of metabolite absence with nonsense mutations was detected for the biosynthetic pathways of an indolic glucosinolate hydrolysis product, a hydroxycinnamic acid amine and a flavonoid triglycoside. Consequently, a direct link between metabolic phenotype and genotype was detected without using segregating populations. Moreover, genomics can help to identify biosynthetic enzymes in metabolomics experiments. Our study elucidates the chemical composition of the rhizosphere and its natural variation in A. thaliana, which is important for the attraction and shaping of microbial communities. PMID:27363486

  7. Stoichiometry constrains microbial response to root exudation- insights from a model and a field experiment in a temperate forest

    J. E. Drake

    2013-02-01

    Full Text Available Plant roots release a wide range of chemicals into soils. This process, termed root exudation, is thought to increase the activity of microbes and the exoenzymes they synthesize, leading to accelerated rates of carbon (C mineralization and nutrient cycling in rhizosphere soils relative to bulk soils. The nitrogen (N content of microbial biomass and exoenzymes may introduce a stoichiometric constraint on the ability of microbes to effectively utilize the root exudates, particularly if the exudates are rich in C but low in N. We combined a theoretical model of microbial activity with an exudation experiment to test the hypothesis that the ability of soil microbes to utilize root exudates for the synthesis of additional biomass and exoenzymes is constrained by N availability. The field experiment simulated exudation by automatically pumping solutions of chemicals often found in root exudates ("exudate mimics" containing C alone or C in combination with N (C : N ratio of 10 through microlysimeter "root simulators" into intact forest soils in two 50-day experiments. The delivery of C-only exudate mimics increased microbial respiration but had no effect on microbial biomass or exoenzyme activities. By contrast, experimental delivery of exudate mimics containing both C and N significantly increased microbial respiration, microbial biomass, and the activity of exoenzymes that decompose low molecular weight components of soil organic matter (SOM, e.g., cellulose, amino sugars, while decreasing the activity of exoenzymes that degrade high molecular weight SOM (e.g., polyphenols, lignin. The modeling results were consistent with the experiments; simulated delivery of C-only exudates induced microbial N-limitation, which constrained the synthesis of microbial biomass and exoenzymes. Exuding N as well as C alleviated this stoichiometric constraint in the model, allowing for increased exoenzyme production, the priming of decomposition, and a net release of N

  8. An association between subclinical familial exudative vitreoretinopathy and rod-cone dystrophy

    Abdullah Ilhan

    2014-10-01

    Full Text Available A 21-year-old Caucasian man presented with a complaint of nyctalopia. Visual acuity in both eyes was 20/20 and anterior segment biomicroscopy results were unremarkable. Fundoscopy revealed peripheral avascular zones, minimal peripheral retinal exudation from the retinal vessels, peripheral retinal telangiectasias and anastomosis in both eyes, and retinal vascular dragging toward the temporal periphery in both eyes. Full field electroretinography showed that rod responses were almost absent and that cone responses were reduced. Macular optical coherence tomography showed normal structure in both eyes. Vascular changes were attributed to a subclinical form of familial exudative vitreoretinopathy. This was an interesting case due to the association of familial exudative vitreoretinopathy with rod-cone dystrophy.

  9. Two cases of exudative retina detachment and uveitis following H1N1 influenza vaccination

    TAO Yong; CHANG Li-bing; ZHAO Min; LI Xiao-xin

    2011-01-01

    Uveitis was a rare adverse event of vaccination.We met two cases of acute uveitis with exudative retinal detachment following vaccination of H1N1 influenza.Case 1 was a 10-year-old boy who was admitted for bilateral blurred vision at 10 days after vaccination of H1N1 influenza.Vitreous opacity was obvious in both eyes.Broad exudative retinal detachment was observed in the right eye.Case 2 was a 47-year-old female who suffered from an acute high fever at 2 days after the vaccination of H1 N1 influenza.Later,she encountered bilateral headache and decreasing vision.In both eyes,mutton fat keratic precipitates,positive Tyndall phenomenon,congestion of optic disc and exudative retinal detachment were observed.

  10. Root exudates drive interspecific facilitation by enhancing nodulation and N2 fixation.

    Li, Bai; Li, Yu-Ying; Wu, Hua-Mao; Zhang, Fang-Fang; Li, Chun-Jie; Li, Xue-Xian; Lambers, Hans; Li, Long

    2016-06-01

    Plant diversity in experimental systems often enhances ecosystem productivity, but the mechanisms causing this overyielding are only partly understood. Intercropping faba beans (Vicia faba L.) and maize (Zea mays L.) result in overyielding and also, enhanced nodulation by faba beans. By using permeable and impermeable root barriers in a 2-y field experiment, we show that root-root interactions between faba bean and maize significantly increase both nodulation and symbiotic N2 fixation in intercropped faba bean. Furthermore, root exudates from maize promote faba bean nodulation, whereas root exudates from wheat and barley do not. Thus, a decline of soil nitrate concentrations caused by intercropped cereals is not the sole mechanism for maize promoting faba bean nodulation. Intercropped maize also caused a twofold increase in exudation of flavonoids (signaling compounds for rhizobia) in the systems. Roots of faba bean treated with maize root exudates exhibited an immediate 11-fold increase in the expression of chalcone-flavanone isomerase (involved in flavonoid synthesis) gene together with a significantly increased expression of genes mediating nodulation and auxin response. After 35 d, faba beans treated with maize root exudate continued to show up-regulation of key nodulation genes, such as early nodulin 93 (ENOD93), and promoted nitrogen fixation. Our results reveal a mechanism for how intercropped maize promotes nitrogen fixation of faba bean, where maize root exudates promote flavonoid synthesis in faba bean, increase nodulation, and stimulate nitrogen fixation after enhanced gene expression. These results indicate facilitative root-root interactions and provide a mechanism for a positive relationship between species diversity and ecosystem productivity. PMID:27217575

  11. Rapid regression of exudative maculopathy in idiopathic retinitis, vasculitis, aneurysms and neuroretinitis syndrome after intravitreal ranibizumab.

    Marín-Lambíes, Cristina; Gallego-Pinazo, Roberto; Salom, David; Navarrete, Javier; Díaz-Llopis, Manuel

    2012-05-01

    The idiopathic retinitis, vasculitis, aneurysms and neuroretinitis syndrome is a rare retinal vascular disorder characterized by multiple leaking aneurysmal dilations, retinal vasculitis, neuroretinitis and peripheral vascular ischemia. Visual loss mainly occurs due to the development of retinal neovascularization and/or exudative maculopathy. Although the treatment of choice has not yet been established, retinal photocoagulation seems to be the best option to control the disease and to prevent its progression. Herein, we report a case of idiopathic retinitis, vasculitis, aneurysms and neuroretinitis syndrome with both retinal neovascularization and macular exudation successfully managed with intravitreal ranibizumab (Lucentis(®)) as adjunctive therapy to retinal photocoagulation. PMID:22949913

  12. Influence of coral and algal exudates on microbially mediated reef metabolism

    Andreas F. Haas

    2013-07-01

    Full Text Available Benthic primary producers in tropical reef ecosystems can alter biogeochemical cycling and microbial processes in the surrounding seawater. In order to quantify these influences, we measured rates of photosynthesis, respiration, and dissolved organic carbon (DOC exudate release by the dominant benthic primary producers (calcifying and non-calcifying macroalgae, turf-algae and corals on reefs of Mo‘orea French Polynesia. Subsequently, we examined planktonic and benthic microbial community response to these dissolved exudates by measuring bacterial growth rates and oxygen and DOC fluxes in dark and daylight incubation experiments. All benthic primary producers exuded significant quantities of DOC (roughly 10% of their daily fixed carbon into the surrounding water over a diurnal cycle. The microbial community responses were dependent upon the source of the exudates and whether the inoculum of microbes included planktonic or planktonic plus benthic communities. The planktonic and benthic microbial communities in the unamended control treatments exhibited opposing influences on DO concentration where respiration dominated in treatments comprised solely of plankton and autotrophy dominated in treatments with benthic plus plankon microbial communities. Coral exudates (and associated inorganic nutrients caused a shift towards a net autotrophic microbial metabolism by increasing the net production of oxygen by the benthic and decreasing the net consumption of oxygen by the planktonic microbial community. In contrast, the addition of algal exudates decreased the net primary production by the benthic communities and increased the net consumption of oxygen by the planktonic microbial community thereby resulting in a shift towards net heterotrophic community metabolism. When scaled up to the reef habitat, exudate-induced effects on microbial respiration did not outweigh the high oxygen production rates of benthic algae, such that reef areas dominated with

  13. Bioavailability of zinc and phosphorus in calcareous soils as affected by citrate exudation

    Duffner, A.; Hoffland, E.; Temminghoff, E.J.M.

    2012-01-01

    Aims Zinc (Zn) and phosphorus (P) deficiency often occurs at the same time and limits crop production in many soils. It has been suggested that citrate root exudation is a response of plants to both deficiencies. We used white lupin (Lupinus albus L.) as a model plant to clarify if citrate exuded by roots could increase the bioavailability of Zn and P in calcareous soils. Methods White lupin was grown in nutrient solution and in two calcareous soils in a rhizobox. Rhizosphere soil solution wa...

  14. Characterisation and molecular association of Nigerian and Sudanese Acacia gum exudates

    The chemical and physicochemical characteristics of gum exudate samples harvested from mature trees of Acacia senegal at two specific locations in Nigeria have been investigated together with gum samples harvested from Acacia senegal and Acacia seyal originating from Sudan. The monosaccharide sugar ...

  15. Potential of Root Exudates from Wetland Plants and Their Potential Role for Denitrification and Allelopathic Interactions

    Zhai, Xu

    chemicals to suppress the growth of native species. Phragmites australis is recognized as the most invasive species in wetland ecosystems in North America, and allelopathy has been reported to be involved in the invasion success of the introduced exotic P. australis. The composition of the root exudates may...

  16. Clover root exudate produces male-biased sex ratios and accelerates male metamorphic timing in wood frogs.

    Lambert, Max R

    2015-12-01

    In amphibians, abnormal metamorph sex ratios and sexual development have almost exclusively been considered in response to synthetic compounds like pesticides or pharmaceuticals. However, endocrine-active plant chemicals (i.e. phytoestrogens) are commonly found in agricultural and urban waterways hosting frog populations with deviant sexual development. Yet the effects of these compounds on amphibian development remain predominantly unexplored. Legumes, like clover, are common in agricultural fields and urban yards and exude phytoestrogen mixtures from their roots. These root exudates serve important ecological functions and may also be a source of phytoestrogens in waterways. I show that clover root exudate produces male-biased sex ratios and accelerates male metamorphosis relative to females in low and intermediate doses of root exudate. My results indicate that root exudates are a potential source of contaminants impacting vertebrate development and that humans may be cultivating sexual abnormalities in wildlife by actively managing certain plant species. PMID:27019728

  17. Changes of organic acid exudation and rhizosphere pH in rice plants under chromium stress

    The effect of chromium (Cr) stress on the changes of rhizosphere pH, organic acid exudation, and Cr accumulation in plants was studied using two rice genotypes differing in grain Cr accumulation. The results showed that rhizosphere pH increased with increasing level of Cr in the culture solution and with an extended time of Cr exposure. Among the six organic acids examined in this experiment, oxalic and malic acid contents were relatively higher, and had a significant positive correlation with the rhizosphere pH, indicating that they play an important role in changing rhizosphere pH. The Cr content in roots was significantly higher than that in stems and leaves. Cr accumulation in plants was significantly and positively correlated with rhizosphere pH, and the exudation of oxalic, malic and citric acids, suggesting that an increase in rhizosphere pH, and exudation of oxalic, malic and citric acid enhances Cr accumulation in rice plants. - Rhizosphere pH and organic acid exudation of rice roots are markedly affected by chromium level in culture solution

  18. Decision support system for the detection and grading of hard exudates from color fundus photographs

    Jaafar, Hussain F.; Nandi, Asoke K.; Al-Nuaimy, Waleed

    2011-11-01

    Diabetic retinopathy is a major cause of blindness, and its earliest signs include damage to the blood vessels and the formation of lesions in the retina. Automated detection and grading of hard exudates from the color fundus image is a critical step in the automated screening system for diabetic retinopathy. We propose novel methods for the detection and grading of hard exudates and the main retinal structures. For exudate detection, a novel approach based on coarse-to-fine strategy and a new image-splitting method are proposed with overall sensitivity of 93.2% and positive predictive value of 83.7% at the pixel level. The average sensitivity of the blood vessel detection is 85%, and the success rate of fovea localization is 100%. For exudate grading, a polar fovea coordinate system is adopted in accordance with medical criteria. Because of its competitive performance and ability to deal efficiently with images of variable quality, the proposed technique offers promising and efficient performance as part of an automated screening system for diabetic retinopathy.

  19. Oxalate and root exudates enhance the desorption of p,p'-DDT from soils.

    Luo, Lei; Zhang, Shuzhen; Shan, Xiao-Quan; Zhu, Yong-Guan

    2006-05-01

    The abiotic desorption of p,p'-DDT from seven Chinese soils spiked with p,p'-DDT and the effects of oxalate at 0.001-0.1M and the root exudates of maize, wheat, and ryegrass were evaluated using batch experiments. Soil organic carbon played a predominant role in the retention of DDT. Oxalate significantly increased the desorption of p,p'-DDT, with the largest increments ranging from 11% to 54% for different soils. Oxalate addition also resulted in the increased release of dissolved organic carbon and inorganic ions from soils. Root exudates had similar effects to those of oxalate. Root exudates significantly increased DDT desorption from the soils, and the general trend was similar among the plant species studied for all the soils (p > 0.05). Low molecular weight dissolved organic carbon amendments caused partial dissolution of the soil structure, such as the organo-mineral linkages, resulting in the release of organic carbon and metal ions and thus the subsequent enhanced desorption of DDT from the soils. The enhancing effects of oxalate and root exudates on DDT desorption were influenced by the contents of soil organic carbon and dissolved organic carbon in soils. PMID:16307790

  20. Compositional analysis and rheological characterization of gum tragacanth exudates from six species of Iranian Astragalus

    Balaghi, Sima; Mohammadifar, Mohammad Amin; Zargaraan, Azizollaah;

    2011-01-01

    The sugar composition and viscoelastic behaviour of Iranian gum tragacanth exuded by six species of Astragalus was investigated at a concentration of 1.3% and varying ionic strength using a controlled shear-rate rheometer. Compositional analysis of the six species of gum tragacanth by high...

  1. Lactoferrin, myeloperoxidase, lysozyme and eosinophil cationic protein in exudate in delayed type hypersensitivity

    Lerche, A; Bisgaard, H; Christensen, J D; Venge, P; Dahl, R; Søndergaard, J

    1988-01-01

    A skin window technique was used to study the morphology of leucocytes in upper dermis and exudate during nickel challenge in patients with contact allergy to nickel. Contact allergic patients and healthy volunteers tested with a skin widow without addition of nickel to the chamber medium served as...

  2. Influence of aluminum on growth, mineral nutrition and organic acid exudation of rambutan (Nephelium lappaceum)

    A randomized complete block design experiment with six aluminum (Al) concentrations was carried out to evaluate the effect of aluminum on nutrient content, plant growth, dry matter production and Al-induced organic acid exudation in rambutan (Nephelium lappaceum). One rambutan cultivar was grown in...

  3. Mapping Soil Carbon from Cradle to Grave: C Transformations of Root Exudates and Plant Litter

    Pett-Ridge, J.; Keiluweit, M.; Nuccio, E.; Bougoure, J.; Weber, P. K.; Brodie, E.; Mayali, X.; Shi, S.; Hwang, M.; Thelen, M.; Firestone, M.; Kleber, M.; Nico, P. S.

    2013-12-01

    Carbon cycling in the rhizosphere is a nexus of biophysical interactions between plant roots, microorganisms, and the soil organo-mineral matrix. Plant roots provide 30-40% of soil organic C inputs, accelerate the rate of organic matter mineralization by ~10X, and support an active microhabitat for microbial transformation of soil C. Our research on how roots influence decomposition of soil organic matter in both simplified and complex microcosms uses geochemical characterization, molecular microbiology, isotope tracing, metabolomics and novel imaging approaches (';ChipSIP' and ';STXM-SIMS') to trace the fate of isotopically labelled root exudates and plant tissues. Our previous work suggests root exudates drive O2 limitation, alter metal chemistry and mineralogy, and influence the availability of SOM. Our most recent experiments using synthetic rhizospheres were designed to identify the role of root exudates on ligno-cellulose decomposition in soils. Cultures of 13C/15N-labeled single plant cells (lignin-rich tracheary elements) were added to rhizosphere microcosm soils, and their decomposition followed under the influence of different root exudates using the dual imaging approach ';STXM-SIMS'. Using this combination of X-ray spectromicroscopy and NanoSIMS, we imaged the deconstruction of 13C/15N-labeled ligno-cellulose in situ, and mapped associations of plant cell-derived decomposition products with specific soil minerals. We've also looked at microbial community function in the more complex rhizospheres surrounding roots of the annual grass Avena fatua. Using an isotope array that allows us to follow root C into bacterial, fungal, and microfaunal communities, we tracked the movement of 13C from labeled exudates and 15N from labeled root litter into the soil microbial community. Our results indicate that the microbial communities involved in litter decomposition differ in rhizosphere versus bulk soils, which may have implications for carbon stabilization in soil.

  4. Vitamin D nutritional status and vitamin D regulated antimicrobial peptides in serum and pleural fluid of patients with infectious and noninfectious pleural effusions

    Amado, Carlos A.; García-Unzueta, María T; Fariñas, M. Carmen; Santos, Francisca; Ortiz, María; Muñoz-Cacho, Pedro; Amado, José A

    2016-01-01

    Background Vitamin D and vitamin D dependent antimicrobial peptides such as Cathelicidin (LL-37) and β-defensin 2 have an important role in innate and adaptative immunity, but their role in pleural effusions has not been studied before. Methods Serum and pleural fluid samples from 152 patients with pleural effusion were collected, corresponding to 45 transudates and 107 exudates, 51 infectious effusions (14 complicated and 37 non-complicated), 44 congestive heart failure effusions and 38 mali...

  5. Management of Pleural Effusion, Empyema, and Lung Abscess

    Yu, Hyeon

    2011-01-01

    Pleural effusion is an accumulation of fluid in the pleural space that is classified as transudate or exudate according to its composition and underlying pathophysiology. Empyema is defined by purulent fluid collection in the pleural space, which is most commonly caused by pneumonia. A lung abscess, on the other hand, is a parenchymal necrosis with confined cavitation that results from a pulmonary infection. Pleural effusion, empyema, and lung abscess are commonly encountered clinical problem...

  6. Root exudation of phytochemicals in Arabidopsis follows specific patterns that are developmentally programmed and correlate with soil microbial functions.

    Jacqueline M Chaparro

    Full Text Available Plant roots constantly secrete compounds into the soil to interact with neighboring organisms presumably to gain certain functional advantages at different stages of development. Accordingly, it has been hypothesized that the phytochemical composition present in the root exudates changes over the course of the lifespan of a plant. Here, root exudates of in vitro grown Arabidopsis plants were collected at different developmental stages and analyzed using GC-MS. Principle component analysis revealed that the composition of root exudates varied at each developmental stage. Cumulative secretion levels of sugars and sugar alcohols were higher in early time points and decreased through development. In contrast, the cumulative secretion levels of amino acids and phenolics increased over time. The expression in roots of genes involved in biosynthesis and transportation of compounds represented in the root exudates were consistent with patterns of root exudation. Correlation analyses were performed of the in vitro root exudation patterns with the functional capacity of the rhizosphere microbiome to metabolize these compounds at different developmental stages of Arabidopsis grown in natural soils. Pyrosequencing of rhizosphere mRNA revealed strong correlations (p<0.05 between microbial functional genes involved in the metabolism of carbohydrates, amino acids and secondary metabolites with the corresponding compounds released by the roots at particular stages of plant development. In summary, our results suggest that the root exudation process of phytochemicals follows a developmental pattern that is genetically programmed.

  7. Root Exudation of Phytochemicals in Arabidopsis Follows Specific Patterns That Are Developmentally Programmed and Correlate with Soil Microbial Functions

    Sugiyama, Akifumi; Manter, Daniel K.; Vivanco, Jorge M.

    2013-01-01

    Plant roots constantly secrete compounds into the soil to interact with neighboring organisms presumably to gain certain functional advantages at different stages of development. Accordingly, it has been hypothesized that the phytochemical composition present in the root exudates changes over the course of the lifespan of a plant. Here, root exudates of in vitro grown Arabidopsis plants were collected at different developmental stages and analyzed using GC-MS. Principle component analysis revealed that the composition of root exudates varied at each developmental stage. Cumulative secretion levels of sugars and sugar alcohols were higher in early time points and decreased through development. In contrast, the cumulative secretion levels of amino acids and phenolics increased over time. The expression in roots of genes involved in biosynthesis and transportation of compounds represented in the root exudates were consistent with patterns of root exudation. Correlation analyses were performed of the in vitro root exudation patterns with the functional capacity of the rhizosphere microbiome to metabolize these compounds at different developmental stages of Arabidopsis grown in natural soils. Pyrosequencing of rhizosphere mRNA revealed strong correlations (p<0.05) between microbial functional genes involved in the metabolism of carbohydrates, amino acids and secondary metabolites with the corresponding compounds released by the roots at particular stages of plant development. In summary, our results suggest that the root exudation process of phytochemicals follows a developmental pattern that is genetically programmed. PMID:23383346

  8. Effects of root exudates on the leachability, distribution, and bioavailability of phenanthrene and pyrene from mangrove sediments.

    Jia, Hui; Lu, Haoliang; Liu, Jingchun; Li, Jian; Dai, Minyue; Yan, Chongling

    2016-03-01

    In this study, column leaching experiments were used to evaluate the leachability, distribution and bioavailability of phenanthrene and pyrene by root exudates from contaminated mangrove sediments. We observed that root exudates significantly promoted the release and enhanced the bioavailability of phenanthrene and pyrene from sediment columns. The concentration of phenanthrene and pyrene and cumulative content released from the analyzed sediment samples following root exudate rinsing decreased in the following order: citric acid > oxalic acid > malic acid. After elution, the total concentrations of phenanthrene and pyrene in sediment layers followed a descending order of bottom (9-12 cm) > middle (5-7 cm) > top (0-3 cm). Furthermore, a positive correlation between leachate pH values and PAH concentrations of the leachate was found. Consequently, the addition of root exudates can increase the leachability and bioavailability of phenanthrene and pyrene. PMID:26573317

  9. Plant growth inhibiting flavonoids in exudate of Cistus ladanifer and in associated soils.

    Chaves, N; Sosa, T; Escudero, J C

    2001-03-01

    Of the aglycone flavonoids identified in the exudate of cistus ladanifer, two, the flavone apigenin-4'-(O)-methyl and the flavonol kaempferol-3,7-di(O)-methyl inhibit development of the seedlings of Rumex crispus at 0.5 and 1 mM. Additive effects were observed between the major flavonols of the exudate kaempferol-3-(O)-methyl and kaempferol-3,7-di-(O)-methyl in inhibiting the size of the cotyledons and delaying the germination and cotyledon emergence. The presence of apigenin-4'-(O)-methyl, kaempferol-3,7-di-(O)-methyl, and kaempferol-3-(O)-methyl was detected in the soils associated with C. ladanifer during the summer and autumn months. That these compounds are present in the soil and are not restricted to the leaves provides support for the hypothesis that C. ladanifer has allelopathic potential. PMID:11441450

  10. Micropropagation and Phenolic exudation protocol for Excoecaria agallocha-an important mangrove

    Manickam Arumugam; Rajaram Panneerselvam

    2012-01-01

    Objective: To develop a standard micropropagation protocol for an important vulnerable mangrove Excoecaria agallocha. Methods: Collection of explants, surface sterilization, phenolic exudation and medium was standardized. Shoot induction, shoot multiplication and rooting were carried out in MMS medium supplemented with BAP, Kinetin, Zeatin, 2ip, NAA, IAA and IBA. Hardening was carried out after root well established. Results: The best phenolic exudation removal was resulted in 4 g/L activated charcoal. The maximum shoot induction response showed in MMS medium and better shoot induction was performed in the concentration of BAP (3.9 μmol) and NAA (1.34 μmol). Rooting induction was performed high range at 5.02 μmol of IAA. Well rooted micro-shoots were hardened and acclimatized. Conclusions: From the present investigation, it can be concluded that a standard micropropagation protocol was developed for an important vulnerable mangrove species.

  11. Effect of soil water content on spatial distribution of root exudates and mucilage in the rhizosphere

    Holz, Maire; Zarebanadkouki, Mohsen; Kuzyakov, Yakov; Carminati, Andrea

    2016-04-01

    Water and nutrients are expected to become the major factors limiting food production. Plant roots employ various mechanisms to increase the access to these limited soil resources. Low molecular root exudates released into the rhizosphere increase nutrient availability, while mucilage improves water availability under low moisture conditions. However, studies on the spatial distribution and quantification of exudates in soil are scarce. Our aim was therefore to quantify and visualize root exudates and mucilage distribution around growing roots using neutron radiography and 14C imaging at different levels of water stress. Maize plants were grown in rhizotrons filled with a silty soil and were exposed to varying soil conditions, from optimal to dry. Mucilage distribution around the roots was estimated from the profiles of water content in the rhizosphere - note that mucilage increases the soil water content. The profiles of water content around different root types and root ages were measured with neutron radiography. Rhizosphere extension was approx. 0.7 mm and did not differ between wet and dry treatments. However, water content (i.e. mucilage concentration) in the rhizosphere of plants grown in dry soils was higher than for plants grown under optimal conditions. This effect was particularly pronounced near the tips of lateral roots. The higher water contents near the root are explained as the water retained by mucilage. 14C imaging of root after 14CO2 labeling of shoots (Pausch and Kuzyakov 2011) was used to estimate the distribution of all rhizodeposits. Two days after labelling, 14C distribution was measured using phosphor-imaging. To quantify 14C in the rhizosphere a calibration was carried out by adding given amounts of 14C-glucose to soil. Plants grown in wet soil transported a higher percentage of 14C to the roots (14Croot/14Cshoot), compared to plants grown under dry conditions (46 vs. 36 %). However, the percentage of 14C allocated from roots to

  12. Methylobacterium-plant interaction genes regulated by plant exudate and quorum sensing molecules

    Manuella Nóbrega Dourado; Andrea Cristina Bogas; Pomini, Armando M.; Fernando Dini Andreote; Maria Carolina Quecine; Marsaioli, Anita J.; Welington Luiz Araújo

    2013-01-01

    Bacteria from the genus Methylobacterium interact symbiotically (endophytically and epiphytically) with different plant species. These interactions can promote plant growth or induce systemic resistance, increasing plant fitness. The plant colonization is guided by molecular communication between bacteria-bacteria and bacteria-plants, where the bacteria recognize specific exuded compounds by other bacteria (e.g. homoserine molecules) and/or by the plant roots (e.g. flavonoids, ethanol and met...

  13. Rapid Regression of Exudative Maculopathy in Idiopathic Retinitis, Vasculitis, Aneurysms and Neuroretinitis Syndrome after Intravitreal Ranibizumab

    Marín-Lambíes, Cristina; Gallego-Pinazo, Roberto; Salom, David; Navarrete, Javier; Díaz-Llopis, Manuel

    2012-01-01

    The idiopathic retinitis, vasculitis, aneurysms and neuroretinitis syndrome is a rare retinal vascular disorder characterized by multiple leaking aneurysmal dilations, retinal vasculitis, neuroretinitis and peripheral vascular ischemia. Visual loss mainly occurs due to the development of retinal neovascularization and/or exudative maculopathy. Although the treatment of choice has not yet been established, retinal photocoagulation seems to be the best option to control the disease and to preve...

  14. Roles of antibody and complement in the bactericidal activity of mouse peritoneal exudate neutrophils.

    Hart, P. H.; Spencer, L. K.; Hill, N L; McDonald, P J; Finlay-Jones, J. J.

    1987-01-01

    The contributions of complement and antibody to phagocytosis and, as a separate process, intracellular killing of Proteus mirabilis, were investigated using mouse peritoneal exudate neutrophils. Phagocytosis of P. mirabilis was promoted by both immune mouse (IMS) and normal mouse (NMS) sera. Opsonization by IMS promoted significantly greater phagocytosis than did NMS, as did NMS compared with heated IMS (HIMS). The ability of NMS to opsonize P. mirabilis for both phagocytosis and phagocytic k...

  15. An association between subclinical familial exudative vitreoretinopathy and rod-cone dystrophy

    Abdullah Ilhan; Umit Yolcu; Fatih Cakir Gundogan; Fahrettin Akay

    2014-01-01

    A 21-year-old Caucasian man presented with a complaint of nyctalopia. Visual acuity in both eyes was 20/20 and anterior segment biomicroscopy results were unremarkable. Fundoscopy revealed peripheral avascular zones, minimal peripheral retinal exudation from the retinal vessels, peripheral retinal telangiectasias and anastomosis in both eyes, and retinal vascular dragging toward the temporal periphery in both eyes. Full field electroretinography showed that rod responses were almost absent an...

  16. Effect of Bark Extract and Gum Exudate of Commiphora Caudata on Aspirin Induced Ulcer in Rats

    R Nanthakumar; Ambrose S Stephen; E Sriram; Babu, G.; K Chitra; C Uma maheswara Reddy

    2009-01-01

    Commiphora caudata is used in Indian folk medicine as an antiulcerogenic agent. Despite of its promising use, there has been no scientific report present regarding its antiulcer activity. Therefore, this study was designed to evaluate the antiulcer activity of bark extract and gum exudate of commiphora caudata on aspirin induced ulcer in rats. Acute toxicity study was performed and 200 mg/kg was selected as an effective dose. Four groups of Albino Swiss rats were included in this study. Aspir...

  17. Differing Organic Acid Exudation Pattern Explains Calcifuge and Acidifuge Behaviour of Plants

    Tyler, Germund; Ström, Lena

    1995-01-01

    Many vascular plant species are unable to colonize calcareous sites. Thus, the floristic composition of adjacent limestone and acid silicate soils differs greatly. The inability of calcifuge plants to establish in limestone sites seems related to a low capacity of such plants to solubilize and absorb Fe or phosphate from these soils. Until now, mechanisms regulating this differing ability of plants to colonize limestone sites have not been elucidated. We propose that contrasting exudation of ...

  18. Comparative effects of argon green and krypton red laser photocoagulation for patients with diabetic exudative maculopathy.

    Khairallah, M; Brahim, R; Allagui, M.; Chachia, N

    1996-01-01

    AIMS/BACKGROUND: Focal treatment of diabetic macular oedema is usually done using a haemoglobin absorbing wave-length, such as argon green laser. This study aimed to compare photocoagulation with argon green (514 nm) and krypton red (647 nm), which is poorly absorbed by haemoglobin, in the focal treatment of patients with diabetic exudative maculopathy. METHODS: A total of 151 eyes of 78 outpatients were assigned randomly to receive either argon green (n = 79) or krypton red (n = 72) laser tr...

  19. Phytochemical screening of the exudate of Aloe otallensis and its effect on Leishmania donovani

    Zerihun Tesfaye Nigusse

    2016-06-01

    Full Text Available Objective: To evaluate the antileishmanial activity of methanolic extract of Aloe otallensis (A. otallensis on the promastigote stage of Leishmania donovani (L. donovani as compared to standard drugs and to screen its phytochemical constituents. Methods: Phytochemical screening was done by using the method mentioned by Evans and Trease on methanolic extract of the exudates of Aloe otallensis leaves. The extract was also evaluated for in vitro antileishmanial activity against L. donavani which is found from the Parasitology Unit of Black Lion Hospital. The result was compared to standard drugs of sodium stibogluconate, milfostin and paramomycin. Results: The extract has a good antileishmanial activity with an IC50 of 0.1230 μg/mL on L. donovani (AM 563. The experimental data showed that relatively it had better activity than paramomycin and milfostin but less activity than sodium stibogluconate. The data analyses were done by GraphPad Prism version 5 software after it was read by ELISA reader at the wave length of 650 nm. The phytochemical screening of the exudates of A. otallensis showed the presence of phenol, alkaloid and saponin. Conclusions: The methanol extract of the exudates of A. otallensis has a good antileishmaniasis activity and this may be attributed to phenol, alkaloid and saponin present in the plant. But it needs further analysis for the conformation of which constituent presents in high concentration to know which one has the strongest effect.

  20. Purification of exuding water in reclaimed land by combination of irradiation and biological treatment

    The dirty water exuding from garbage-filled reclaimed land contains a large quantity of organic contaminating substances. The main component of the contaminating substances is humus called humic acid and fulvic acid. It is difficult to apply biological treatment such as activated sludge process to exuding water because the biological decomposition property of the humus is generally poor. Sufficient effect cannot be expected by physicochemical process such as active carbon treatment and flocculation-precipitation treatment because the molecular weight distribution of the humus is very wide. If irradiation and biological treatment can be combined, the irradiation dose required can be largely reduced. Therefore, exuding water was sampled in Tokyo Bay No.15 reclaimed land, and Co-60 gamma ray was irradiated to see the change of its BOD. The irradiating condition in irradiation-biological treatment was clarified, and the possible method of the combined treatment was decided for trial. The peak value of BOD and the dose required to reach the peak were almost proportional to the initial concentration, and pH did not much affect the change of BOD. The low dose rate did not bring about much merit. (Kako, I.)

  1. Phytochemical screening of the exudate of Aloe otallensis and its effect on Leishmania donovani

    Zerihun Tesfaye Nigusse; WoldeaAbebe Wondifraw; Sefinew MigbaruAbate

    2016-01-01

    Objective: To evaluate the antileishmanial activity of methanolic extract of Aloe otallensis (A. otallensis) on the promastigote stage of Leishmania donovani (L. donovani) as compared to standard drugs and to screen its phytochemical constituents. Methods: Phytochemical screening was done by using the method mentioned by Evans and Trease on methanolic extract of the exudates of Aloe otallensis leaves. The extract was also evaluated for in vitro antileishmanial activity against L. donavani which is found from the Parasitology Unit of Black Lion Hospital. The result was compared to standard drugs of sodium stibogluconate, milfostin and paramomycin. Results: The extract has a good antileishmanial activity with an IC50 of 0.1230 μg/mL on L. donovani (AM 563). The experimental data showed that relatively it had better activity than paramomycin and milfostin but less activity than sodium stibogluconate. The data analyses were done by GraphPad Prism version 5 software after it was read by ELISA reader at the wave length of 650 nm. The phytochemical screening of the exudates of A. otallensis showed the presence of phenol, alkaloid and saponin. Conclusions: The methanol extract of the exudates of A. otallensis has a good anti-leishmaniasis activity and this may be attributed to phenol, alkaloid and saponin present in the plant. But it needs further analysis for the conformation of which constituent presents in high concentration to know which one has the strongest effect.

  2. Serum VEGF and CFH in Exudative Age-Related Macular Degeneration

    Haas, Paulina; Steindl, Kerstin; Aggermann, Tina; Schmid-Kubista, Katharina; Krugluger, Walter; Hageman, Gregory S.; Binder, Susanne

    2014-01-01

    Purpose To determine serum vascular endothelial growth factor 165 (VEGF165) levels and the association of the complement factor H gene (CFH) Y402H polymorphism in patients with exudative age-related macular degeneration (AMD) in comparison to unaffected control subjects. Methods Sixty-six AMD patients and 66 healthy age- and gender-matched controls were included in this case-control study. The serum VEGF165 was assayed by ELISA (R&D). Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism analysis. Chisquared tests were used regarding the polymorphism, a t-test regarding the VEGF-levels. Results Levels of serum VEGF165 were similar in both groups (p-value = 0.2112). Genotype frequency differed significantly between patients with exudative AMD and the healthy control group (p = 0.003136). The serum VEGF165 levels were similar irrespective of the presence of the CFH Y402H polymorphism (p = 0.4113) and independent of the specific genotype (p = 0.9634). Conclusion In the present study exudative AMD is not associated to serum VEGF165 levels; furthermore, our data does not establish a statistical link between VEGF165 and the CFH Y402H polymorphism. PMID:21158586

  3. Effect of Bark Extract and Gum Exudate of Commiphora Caudata on Aspirin Induced Ulcer in Rats

    R Nanthakumar

    2009-01-01

    Full Text Available Commiphora caudata is used in Indian folk medicine as an antiulcerogenic agent. Despite of its promising use, there has been no scientific report present regarding its antiulcer activity. Therefore, this study was designed to evaluate the antiulcer activity of bark extract and gum exudate of commiphora caudata on aspirin induced ulcer in rats. Acute toxicity study was performed and 200 mg/kg was selected as an effective dose. Four groups of Albino Swiss rats were included in this study. Aspirin suspended in 0.5 % carboxymethyl cellulose (CMC was given orally to group 1 rats as a negative control group. Group 2 and group 3 animals received methanolic extract and gum exudate of commiphora caudata respectively. Sucralfate was given orally to group 4 animals as a positive control. The methanolic extract of commiphora caudata has been found to reduce total acidity as much as by sucralfate. However, it has not changed the fluid secretion. The gum preparation not only reduced the total acidity but also considerably reduce the gastric fluid secretion. In case of ulcer score sucralfate, methanolic extract and the gum have produced the low ulcer score compared to aspirin. Increased gastric mucosal protective mechanism by bark extract and gum exudate is probably due to the presence of some active principles present in the plant. However, further investigations are required to elucidate their exact mechanism of anti-ulcer activity.

  4. Casuarina root exudates alter the physiology, surface properties, and plant infectivity of Frankia sp Strain CcI3

    Beauchemin, Nicholas J.; Furnholm, Teal; Lavenus, Julien; Svistoonoff, Sergio; Doumas, Patrick; Bogusz, Didier; Laplaze, Laurent; Tisa, Louis S.

    2012-01-01

    The actinomycete genus Frankia forms nitrogen-fixing symbioses with 8 different families of actinorhizal plants, representing more than 200 different species. Very little is known about the initial molecular interactions between Frankia and host plants in the rhizosphere. Root exudates are important in Rhizobium-legume symbiosis, especially for initiating Nod factor synthesis. We measured differences in Frankia physiology after exposure to host aqueous root exudates to assess their effects on...

  5. Contribution of Individual Chemoreceptors to Sinorhizobium meliloti Chemotaxis Towards Amino Acids of Host and Nonhost Seed Exudates.

    Webb, Benjamin A; Helm, Richard F; Scharf, Birgit E

    2016-03-01

    Plant seeds and roots exude a spectrum of molecules into the soil that attract bacteria to the spermosphere and rhizosphere, respectively. The alfalfa symbiont Sinorhizobium meliloti utilizes eight chemoreceptors (McpT to McpZ and IcpA) to mediate chemotaxis. Using a modified hydrogel capillary chemotaxis assay that allows data quantification and larger throughput screening, we defined the role of S. meliloti chemoreceptors in sensing its host, Medicago sativa, and a closely related nonhost, Medicago arabica. S. meliloti wild type and most single-deletion strains displayed comparable chemotaxis responses to host or nonhost seed exudate. However, while the mcpZ mutant responded like wild type to M. sativa exudate, its reaction to M. arabica exudate was reduced by 80%. Even though the amino acid (AA) amounts released by both plant species were similar, synthetic AA mixtures that matched exudate profiles contributed differentially to the S. meliloti wild-type response to M. sativa (23%) and M. arabica (37%) exudates, with McpU identified as the most important chemoreceptor for AA. Our results show that S. meliloti is equally attracted to host and nonhost legumes; however, AA play a greater role in attraction to M. arabica than to M. sativa, with McpZ being specifically important in sensing M. arabica. PMID:26713349

  6. Effect of root exudates of different resistant varieties of cucumber on fusarium wilt and preliminary studies on their resistance mechanism

    Benli HUANG; Yundong XU; Ye WU; Shunqi ZHANG; Xuchao CHEN

    2008-01-01

    This study investigated the effect of root exudates of cucumber varieties, Jinyan 4 (susceptible variety), Jinchun 4 (resistant variety) and Yinnan Black seed squash on fusa-rium wilt. The results showed that fusarium wilt occurrence of plants treated with the root exudate of Jinyan 4 was earlier. The infection rate was significantly higher 15 days after inoculation, but similar to the control 20 days after inocula-tion. In contrast, the infection rate of plants treated with the root exudate of Jinchun 4 was significantly lower than that of the control. The plant height and fresh weight of Jinyan 4 treated with its own root exudate were lower than those of the control, and the root vigor decreased but the conductance increased. There was no significant effect of the root exudates from Jinchun 4 and Black seed squash on plant height and fresh mass of Jinyan 4. We found that the root exudate of susceptible cucumber variety stimulated the growth of Fusarium oxysporum pathogen, in contrast, that of resistance variety and Black seed squash suppressed the growth.

  7. Isolation and identification of Desmodium root exudates from drought tolerant species used as intercrops against Striga hermonthica.

    Hooper, A M; Caulfield, J C; Hao, B; Pickett, J A; Midega, C A O; Khan, Z R

    2015-09-01

    Plants from the genus Desmodium, in particular D. uncinatum, are used on sub-Saharan small-holder farms as intercrops to inhibit parasitism of cereal crops by Striga hermonthica and Striga asiatica via an allelopathic mechanism. The search for Desmodium species which are adapted to more arid conditions, and which show resilience to increased drought stress, previously identified D. intortum, D. incanum and D. ramosissimum as potential drought tolerant intercrops. Their potential as intercrops was assessed for resource poor areas of rain-fed cereal production where drought conditions can persist through normal meteorological activity, or where drought may have increasing impact through climate change. The chemical composition of the root exudates were characterised and the whole exudate biological activity was shown to be active in pot experiments for inhibition of Striga parasitism on maize. Furthermore, rain fed plot experiments showed the drought tolerant Desmodium intercrops to be effective for Striga inhibition. This work demonstrates the allelopathic nature of the new drought tolerant intercrops through activity of root exudates and the major compounds seen in the exudates are characterised as being C-glycosylflavonoid. In young plants, the exudates show large qualitative differences but as the plants mature, there is a high degree of convergence of the C-glycosylflavonoid exudate chemical profile amongst active Desmodium intercrops that confers biological activity. This defines the material for examining the mechanism for Striga inhibition. PMID:26164239

  8. Interaction of root exudates with the mineral soil constituents and their effect on mineral weathering

    Mimmo, T.; Terzano, R.; Medici, L.; Lettino, A.; Fiore, S.; Tomasi, N.; Pinton, R.; Cesco, S.

    2012-04-01

    Plants release significant amounts of high and low molecular weight organic compounds into the rhizosphere. Among these exudates organic acids (e.g. citric acid, malic acid, oxalic acid), phenolic compounds (e.g. flavonoids), amino acids and siderophores of microbial and/or plant origin strongly influence and modify the biogeochemical cycles of several elements, thus causing changes in their availability for plant nutrition. One class of these elements is composed by the trace elements; some of them are essential for plants even if in small concentrations and are considered micronutrients, such as Fe, Zn, Mn. Their solubility and bioavailability can be influenced, among other factors, by the presence in soil solution of low molecular weight root exudates acting as organic complexing agents that can contribute to the mineral weathering and therefore, to their mobilization in the soil solution. The mobilized elements, in function of the element and of its concentration, can be either important nutrients or toxic elements for plants. The objective of this study was to assess the influence of several root exudates (citric acid, malic acid, oxalic acid, genistein, quercetin and siderophores) on the mineralogy of two different soils (an agricultural calcareous soil and an acidic polluted soil) and to evaluate possible synergic or competitive behaviors. X-ray diffraction (XRD) coupled with Electron Probe Micro Analysis (EPMA) was used to identify the crystalline and amorphous phases which were subjected to mineral alteration when exposed to the action of root exudates. Solubilization of trace metals such as Cu, Zn, Ni, Cr, Pb, Cd as well as of major elements such as Si, Al, Fe and Mn was assessed by means of Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Soil microorganisms have proven to decrease mineral weathering by reducing the concentration of active root exudates in solution. Results obtained are an important cornerstone to better understand the

  9. Intravitreal bevacizumab combined with plaque brachytherapy reduces melanoma tumor volume and enhances resolution of exudative detachment

    Houston SK

    2013-01-01

    Full Text Available Samuel K Houston,1 Nisha V Shah,1 Christina Decatur,1 Marcela Lonngi,1 William Feuer,1 Arnold M Markoe,2 Timothy G Murray1–31Department of Ophthalmology, 2Department of Radiation Oncology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, 3Murray Ocular Oncology and Retina, Miami, FL, USABackground: The purpose of this study was to evaluate intravitreal bevacizumab as an adjuvant treatment to plaque brachytherapy in the treatment of choroidal melanoma.Methods: This was a retrospective, consecutive study of 124 patients treated from 2007 to 2009 for choroidal melanoma with plaque brachytherapy. Patients were treated with I-125 plaque brachytherapy with 2 mm margins and 85 Gy to the tumor apex. Consecutive patients were injected intravitreally with 2.5 mg/0.1 mL bevacizumab at a site away from the primary tumor and immediately following plaque removal. Choroidal melanomas were observed using indirect ophthalmoscopy, wide-angle photography, and ultrasound. The main outcome measures were tumor volume, resolution of exudative retinal detachment, and visual acuity.Results: One hundred and twenty-four patients met our inclusion criteria and were included in the analysis. The mean patient age was 65.7 years, and the mean apical tumor height was 4.0 ± 2.7 mm and basal diameter was 12.7 ± 3.0 mm. Mean follow-up was 24 months. Prior to treatment, 100% of tumors had exudative retinal detachment, and pretreatment visual acuity was 20/55 (median 20/40. Tumor control was 100%, metastasis was 0% at last follow-up, and 89.8% had complete resolution of exudative retinal detachment, with a mean time to resolution of 3.36 months. At one month, 43% had complete resolution of exudative retinal detachment, which increased to 73% at 4 months. Visual acuity was 20/62 (median 20/40 at 4 months, with stabilization to 20/57 (median 20/40 at 8 months, 20/56 (median 20/30 at 12 months, and 20/68 (median 20/50 at 24 months. Tumor

  10. Gelation of Soy Milk with Hagfish Exudate Creates a Flocculated and Fibrous Emulsion- and Particle Gel.

    Lukas Böni

    Full Text Available Hagfish slime is an ultra dilute, elastic and cohesive hydrogel that deploys within milliseconds in cold seawater from a glandularly secreted exudate. The slime is made of long keratin-like fibers and mucin-like glycoproteins that span a network which entraps water and acts as a defense mechanism against predators. Unlike other hydrogels, the slime only confines water physically and is very susceptible to mechanical stress, which makes it unsuitable for many processing operations and potential applications. Despite its huge potential, little work has been done to improve and functionalize the properties of this hydrogel. To address this shortcoming, hagfish exudate was mixed with a soy protein isolate suspension (4% w/v and with a soy emulsion (commercial soy milk to form a more stable structure and combine the functionalities of a suspension and emulsion with those of the hydrogel. Hagfish exudate interacted strongly with the soy systems, showing a markedly increased viscoelasticity and water retention. Hagfish mucin was found to induce a depletion and bridging mechanism, which caused the emulsion and suspension to flocculate, making "soy slime", a cohesive and cold-set emulsion- and particle gel. The flocculation network increases viscoelasticity and substantially contributes to liquid retention by entrapping liquid in the additional confinements between aggregated particles and protein fibers. Because the mucin-induced flocculation resembles the salt- or acid-induced flocculation in tofu curd production, the soy slime was cooked for comparison. The cooked soy slime was similar to conventional cooked tofu, but possessed a long-range cohesiveness from the fibers. The fibrous, cold-set, and curd-like structure of the soy slime represents a novel way for a cold coagulation and fiber incorporation into a suspension or emulsion. This mechanism could be used to efficiently gel functionalized emulsions or produce novel tofu-like structured food

  11. Gelation of Soy Milk with Hagfish Exudate Creates a Flocculated and Fibrous Emulsion- and Particle Gel.

    Böni, Lukas; Rühs, Patrick A; Windhab, Erich J; Fischer, Peter; Kuster, Simon

    2016-01-01

    Hagfish slime is an ultra dilute, elastic and cohesive hydrogel that deploys within milliseconds in cold seawater from a glandularly secreted exudate. The slime is made of long keratin-like fibers and mucin-like glycoproteins that span a network which entraps water and acts as a defense mechanism against predators. Unlike other hydrogels, the slime only confines water physically and is very susceptible to mechanical stress, which makes it unsuitable for many processing operations and potential applications. Despite its huge potential, little work has been done to improve and functionalize the properties of this hydrogel. To address this shortcoming, hagfish exudate was mixed with a soy protein isolate suspension (4% w/v) and with a soy emulsion (commercial soy milk) to form a more stable structure and combine the functionalities of a suspension and emulsion with those of the hydrogel. Hagfish exudate interacted strongly with the soy systems, showing a markedly increased viscoelasticity and water retention. Hagfish mucin was found to induce a depletion and bridging mechanism, which caused the emulsion and suspension to flocculate, making "soy slime", a cohesive and cold-set emulsion- and particle gel. The flocculation network increases viscoelasticity and substantially contributes to liquid retention by entrapping liquid in the additional confinements between aggregated particles and protein fibers. Because the mucin-induced flocculation resembles the salt- or acid-induced flocculation in tofu curd production, the soy slime was cooked for comparison. The cooked soy slime was similar to conventional cooked tofu, but possessed a long-range cohesiveness from the fibers. The fibrous, cold-set, and curd-like structure of the soy slime represents a novel way for a cold coagulation and fiber incorporation into a suspension or emulsion. This mechanism could be used to efficiently gel functionalized emulsions or produce novel tofu-like structured food products. PMID:26808048

  12. Compositional differences in simulated root exudates elicit a limited functional and compositional response in soil microbial communities.

    Strickland, Michael S; McCulley, Rebecca L; Nelson, Jim A; Bradford, Mark A

    2015-01-01

    Inputs of low molecular weight carbon (LMW-C) to soil - primarily via root exudates- are expected to be a major driver of microbial activity and source of stable soil organic carbon. It is expected that variation in the type and composition of LMW-C entering soil will influence microbial community composition and function. If this is the case then short-term changes in LMW-C inputs may alter processes regulated by these communities. To determine if change in the composition of LMW-C inputs influences microbial community function and composition, we conducted a 90 day microcosm experiment whereby soils sourced from three different land covers (meadows, deciduous forests, and white pine stands) were amended, at low concentrations, with one of eight simulated root exudate treatments. Treatments included no addition of LMW-C, and the full factorial combination of glucose, glycine, and oxalic acid. After 90 days, we conducted a functional response assay and determined microbial composition via phospholipid fatty acid analysis. Whereas we noted a statistically significant effect of exudate treatments, this only accounted for ∼3% of the variation observed in function. In comparison, land cover and site explained ∼46 and ∼41% of the variation, respectively. This suggests that exudate composition has little influence on function compared to site/land cover specific factors. Supporting the finding that exudate effects were minor, we found that an absence of LMW-C elicited the greatest difference in function compared to those treatments receiving any LMW-C. Additionally, exudate treatments did not alter microbial community composition and observable differences were instead due to land cover. These results confirm the strong effects of land cover/site legacies on soil microbial communities. In contrast, short-term changes in exudate composition, at meaningful concentrations, may have little impact on microbial function and composition. PMID:26322029

  13. Influence of Aluminum and Cadmium Stresses on Mineral Nutrition and Root Exudates in Two Barley Cultivars

    QUO Tian-Rong; ZHANG Guo-Ping; ZHOU Mei-Xue; WU Fei-Bo; CHEN Jin-Xin

    2007-01-01

    A hydroponic experiment was carried out to study the effect of aluminum (Al) and cadmium (Cd) on Al and mineral nutrient contents in plants and Al-induced organic acid exudation in two barley varieties with different Al tolerance. Al-sensitive cv. Shang 70-119 had significantly higher Al content and accumulation in plants than Al-tolerant cv. Gebeina, especially in roots, when subjected to low pH (4.0) and Al treatments (100 μmol L-1 Al and 100 μmol L-1 Al +1.0 μmol L-1 Cd). Cd addition increased Al content in plants exposed to Al stress. Both low pH and Al treatments caused marked reduction in Ca and Mg contents in all plant parts, P and K contents in the shoots and leaves, Fe, Zn and Mo contents in the leaves, Zn and B contents in the shoots, and Mn contents both in the roots and leaves. Moreover, changes in nutrient concentrations were greater in the plants exposed to both Al and Cd than in those exposed only to Al treatment. A dramatic enhancement of malate, citrate, and succinate was found in the plants exposed to 100 μmol L-1 Al relative to the control, and the Al-tolerant cultivar had a considerable higher exudation of these organic acids than the Al-sensitive one, indicating that Al-induced enhancement of these organic acids is very likely to be associated with Al tolerance.

  14. Root Exudates, Rhizosphere Zn Fractions, and Zn Accumulation of Ryegrass at Different Soil Zn Levels

    XU Wei-Hong; LIU Huai; MA Qi-Fu; XIONG Zhi-Ting

    2007-01-01

    A glasshouse experiment was conducted using a root-bag technique to study the root exudates, rhizosphere Zn fractions, and Zn concentrations and accumulations of two ryegrass cultivars (Lolium perenne L. cvs. Airs and Tede) at different soil Zn levels (0, 2, 4, 8, and 16 mmol kg-1 soil). Results indicated that plant growth of the two cultivars was not adversely affected at soil Zn level≤8 mmol kg-1. Plants accumulated more Zn as soil Zn levels increased, and Zn concentrations of shoots were about 540 /μg g-1 in Aris and 583.9μg g-1 in Tede in response to 16 mmol Zn kg-1 soil. Zn ratios of shoots to roots across the soil Zn levels were higher in Tede than in Airs, corresponding with higher rhizosphere available Zn fractions (exchangeable, bound to manganese oxides, and bound to organic matter) in Airs than in Tede. Low-molecular-weight (LMW) organic acids (oxalic, tartaric, malic, and succinic acids) and amino acids (proline, threonine, glutamic acid, and aspartic acid, etc.) were detected in root exudates, and the concentrations of LMW organic acids and amino acids increased with addition of 4 mmol Zn kg-1 soil compared with zero Zn addition. Higher rhizosphere concentrations of oxalic acid, glutamic acid, alanine, phenylalanine, leucine, and proline in Tede than in Airs likely resulted in increased Zn uptake from the soil by Tede than by Airs. The results suggested that genotypic differences in Zn accumulations were mainly because of different root exudates and rhizosphere Zn fractions.

  15. Exudation of organic acids by Lupinus albus and Lupinus angustifolius as affected by phosphorus supply

    Hentschel, Werner; Wiche, Oliver

    2016-04-01

    In phytomining and phytoremediation research mixed cultures of bioenergy crops with legumes hold promise to enhance availability of trace metals and metalloids in the soil plant system. This is due to the ability of certain legumes to mobilize trace elements during acquisition of nutrients making these elements available for co-cultured species. The legumes achieve this element mobilization by exudating carboxylates and enzymes as well as by lowering the pH value in the rhizosphere. The aim of our research was to determine characteristics and differences in the exudation of Lupinus albus and Lupinus angustifolius regarding to quantitative as to qualitative aspects. Especially the affection by phosphorus (P) supply was a point of interest. Thus we conducted laboratory batch experiments, wherein the plants were grown over four weeks under controlled light, moisture and nutritional conditions on sand as substrate. Half of the plants were supplied with 12 mg P per kg substrate, the other half were cultivated under a total lack of P. After cultivation the plants were transferred from the cultivation substrate into a 0,05 mmolṡL‑1 CaCl2 solution. After two hours the plants were removed, moist and dry mass off shoots and roots were measured together with the root length (Tennants' method). Concentrations of exudated carboxylates in the CaCl2 solution were determined via IC (column: Metrosept OrganicAcids, eluent 0.5 molṡL‑1 H2SO4 + 15% acetone, pH=3; 0.5 mLṡmin‑1). As a result four different organic acids were identified (citric acid, fumaric acid, tartaric acid, malic acid) in concentration ranges of 0.15 mgṡL‑1 (fumaric acid) to 9.21 mgṡL‑1 (citric acid). Lupinus angustifolius showed a higher exudation rate (in nmol per cm root length per hour) than Lupinus albus in the presence of phosphorus (e.g. regarding citric acid: 1.99 vs 0.64 nmolṡ(gṡh)‑1). However, as the root complexity and length of L. albus were far higher than of L. angustifolius

  16. BACTERIAL ATTRACTION AND QUORUM SENSING INHIBITION IN CAENORHABDITIS ELEGANS EXUDATES

    Kaplan, Fatma; BADRI, DAYAKAR V.; Zachariah, Cherian; Ajredini, Ramadan; Sandoval, Francisco J.; Roje, Sanja; Lanfang H Levine; Zhang, Fengli; Robinette, Steven. L.; Alborn, Hans T.; Zhao, Wei; Stadler, Michael; Nimalendran, Rathika; Dossey, Aaron T.; Brüschweiler, Rafael

    2009-01-01

    Caenorhabditis elegans, a bacterivorous nematode, lives in complex rotting fruit, soil, and compost environments, and chemical interactions are required for mating, monitoring population density, recognition of food, avoidance of pathogenic microbes, and other essential ecological functions. Despite being one of the best-studied model organisms in biology, relatively little is known about the signals that C. elegans uses to chemically interact with its environment or as defense. C. elegans ex...

  17. Experimental Investigation on Role of Root Mucilage and Microbial Exudates on Soil Water Retention Dynamics

    Gebrenegus, T. B.; Ghezzehei, T.

    2011-12-01

    The release of organic molecules by soil microbes and plant roots to adapt their surrounding represents a substantial portion of the energy use by these organisms. The hypothesis in this study is that the long-chain molecules and hydrophilic nature of the released organic compounds deposited on soil surfaces drastically alters the dynamism of the soil water retention curves (SWRC) of the rhizosphere relative to the bulk soil through direct effect besides the well-known indirect influence of the organic matter by modifying the soil structure and providing energy for the biogeochemical processes. The experiment was set up in such away that it suppresses the indirect effect of organic matter (OM) and rather it traces only its immediate effect on SWRC. To achieve this goal inert and uniform size (0.1-0.11 mm) glassbeads were used. We assumed that wet mixing of the glass beads with OM and slow drying the mixture (40-50oC) for 1-day will lead to deposition of the OM only at the surface of the glass beads, the short time being not enough for aggregate formation. This way we can simulate the natural deposition of OM on soil surfaces. Our argument is that this deposited OM has its own distinct time-dependent SWRC which is different from that of bulk soil. Model exudates including PGA, XA, and SPA are used to mimic the behavior of plant root mucilages, bacterial and fungal exudates respectively. These model exudates at varying concentration (0, 0.008, 0.04, and 0.2 gm/l) were wet mixed with glass beads. SWRC was determined using both water-hanging column and pressure plate for both low and high suction ranges respectively. We will present the effect of exudate type and level of concentration on the dynamic behavior of SWRC of the glassbeads by determining: i) the SWRC for each treatment; ii) the rate of drying and wetting at different intervals; iii) the hysteresis of the retention curves; iv) the saturated hydraulic conductivity.

  18. Exudation of organic acids by a marsh plant and implications on trace metal availability in the rhizosphere of estuarine sediments

    Mucha, Ana P.; Almeida, C. Marisa R.; Bordalo, Adriano A.; Vasconcelos, M. Teresa S. D.

    2005-10-01

    The aim of this work was to identify a variety of low molecular weight organic acids exuded by the sea rush Juncus maritimus collected at two locations with different sediment characteristics (sandy and muddy) and to examine whether specific differences in physico-chemical sediment characteristics influenced plant exudation. Just after collection, plant roots were rinsed and put in contact with deionised water for 2 h. In the obtained solution the organic acids, exuded by the plants, were determined by high performance liquid chromatography. Juncus maritimus was shown to be capable of releasing malonate and oxalate. Sediments and rhizosediments (sediment in contact with the plant roots and rhizomes, corresponding to the area of higher belowground biomass) from the areas where the plants had been collected were characterised in terms of physical and chemical composition, including acid volatile sulphide and total-recoverable metals (Pb, Cr, Cu, Zn, Ni and Cd). It was found that the extent of exudation varied markedly between sites. The identified organic acids were used as extractants of metals from sediments and rhizosediments and the results were compared with those provided by a very commonly used sequential extraction approach, which was carried out in parallel. This work demonstrates that J. maritimus can release organic compounds that can act as complexing agents of trace metal and therefore organic exudates should be accounted for when dealing with estuarine environment quality.

  19. Differential metabolic responses of Beauveria bassiana cultured in pupae extracts, root exudates and its interactions with insect and plant.

    Luo, Feifei; Wang, Qian; Yin, Chunlin; Ge, Yinglu; Hu, Fenglin; Huang, Bo; Zhou, Hong; Bao, Guanhu; Wang, Bin; Lu, Ruili; Li, Zengzhi

    2015-09-01

    Beauveria bassiana is a kind of world-wide entomopathogenic fungus and can also colonize plant rhizosphere. Previous researches showed differential expression of genes when entomopathogenic fungi are cultured in insect or plant materials. However, so far there is no report on metabolic alterations of B. bassiana in the environments of insect or plant. The purpose of this paper is to address this problem. Herein, we first provide the metabolomic analysis of B. bassiana cultured in insect pupae extracts (derived from Euproctis pseudoconspersa and Bombyx mori, EPP and BMP), plant root exudates (derived from asparagus and carrot, ARE and CRE), distilled water and minimal media (MM), respectively. Principal components analysis (PCA) shows that mycelia cultured in pupae extracts and root exudates are evidently separated and individually separated from MM, which indicates that fungus accommodates to insect and plant environments by different metabolic regulation mechanisms. Subsequently, orthogonal projection on latent structure-discriminant analysis (OPLS-DA) identifies differential metabolites in fungus under three environments relative to MM. Hierarchical clustering analysis (HCA) is performed to cluster compounds based on biochemical relationships, showing that sphingolipids are increased in BMP but are decreased in EPP. This observation further implies that sphingolipid metabolism may be involved in the adaptation of fungus to different hosts. In the meantime, sphingolipids are significantly decreased in root exudates but they are not decreased in distilled water, suggesting that some components of the root exudates can suppress sphingolipid to down-regulate sphingolipid metabolism. Pathway analysis finds that fatty acid metabolism is maintained at high level but non-ribosomal peptides (NRP) synthesis is unaffected in mycelia cultured in pupae extracts. In contrast, fatty acid metabolism is not changed but NRP synthesis is high in mycelia cultured in root exudates

  20. Argentinean propolis from Zuccagnia punctata Cav. (Caesalpinieae) exudates: phytochemical characterization and antifungal activity.

    Agüero, María Belén; Gonzalez, Mariela; Lima, Beatriz; Svetaz, Laura; Sánchez, Marianela; Zacchino, Susana; Feresin, Gabriela Egly; Schmeda-Hirschmann, Guillermo; Palermo, Jorge; Wunderlin, Daniel; Tapia, Alejandro

    2010-01-13

    This paper reports the in vitro antifungal activity of propolis extracts from the province of Tucuman (Argentina) as well as the identification of their main antifungal compounds and botanical origin. The antifungal activity was determined by the microdilution technique, using reference microorganisms and clinical isolates. All dermatophytes and yeasts tested were strongly inhibited by different propolis extracts (MICs between 16 and 125 microg mL(-1)). The most susceptible species were Microsporum gypseum, Trichophyton mentagrophytes, and Trichophyton rubrum. The main bioactive compounds were 2',4'-dihydroxy-3'-methoxychalcone 2 and 2',4'-dihydroxychalcone 3. Both displayed strong activity against clinical isolates of T. rubrum and T. mentagrophytes (MICs and MFCs between 1.9 and 2.9 microg mL(-1)). Additionally, galangin 5, pinocembrin 6, and 7-hydroxy-8-methoxyflavanone 9 were isolated from propolis samples and Zuccagnia punctata exudates, showing moderate antifungal activity. This is the first study matching the chemical profile of Z. punctata Cav. exudates with their corresponding propolis, giving strong evidence on the botanical origin of the studied propolis. PMID:19916546

  1. Inf luence of Spirulina platensis exudates on the endocrine and nervous systems of a mammalian model

    Samah; Mamdouh; Mohamed; Fathy; Ashraf; Mohamed; Mohamed; Essa

    2015-01-01

    Objective: To investigate the ef ect of intra-peritoneal injection of purii ed exudates of axenic Spirulina platensis on the mammalian endocrine and nervous systems. Methods: The intra-peritoneal injection of the cyanobacterial exudates in mice was applied. Sex hormonal levels of testosterone and progesterone were measured using radioimmunoassay while the follicular stimulating hormone and luteinizing hormone were evaluated by direct chemiluminescence. In addition, superoxide dismutase, catalase and glutathione peroxidase were monitored in the hippocampus region using spectrophotometric method. The levels of the hippocampal monoamines, dopamine, noradrenaline and serotonin were analyzed by high performance liquid chromatography while the acetyl choline neurotransmitter was measured by colorimetric method using choline/acetylcholine assay kit. Results: A sharp disruption in the sex hormones levels of testosterone, progesterone, follicular stimulating hormone and luteinizing hormone was demonstrated in the serum of the treated mice. At the same time, a signii cant reduction in the endogenous antioxidant defense enzymes, superoxide dismutase, catalase and glutathione peroxidase was observed in the hippocampus region of the injected mice. Moreover, levels of dopamine, noradrenaline, serotonin and acetyl choline neurotransmitter in the same region were signii cantly af ected as a result of the treatment with Spirulina i ltrate. The gas chromatography-mass spectrometer and liquid chromatography mass spectrometry/mass spectrometry analysis showed the presence of some sterol-like compounds in the cyanobacterial i ltrate. Conclusions: This study demonstrated the capability of Spirulina to release detrimental bioactive metabolites into their surrounding that can disrupt the mammalian endocrine and nervous systems.

  2. Recent advances in Rosaceae gum exudates: From synthesis to food and non-food applications.

    Bouaziz, Fatma; Koubaa, Mohamed; Ellouz Ghorbel, Raoudha; Ellouz Chaabouni, Semia

    2016-05-01

    In recent years, great interest has been devoted to the development of new applications for natural gums. These molecules were used for a variety of purposes since they are chemically inert, non-toxic, less expensive, biodegradable and widely available. They represent one of the most abundant raw materials used not only in commercial food products, but also in cosmetic and pharmaceutical products. Plant gums take their advantages compared to other gums (e.g., from animal and microbial sources) mainly because of their acceptance by consumers. Despite of the well description given in literature for the features of plant gum exudates, there is a lack distinguishing the different families that are producing gums, and their potential applications. Among these gums, the ones produced by Rosaceae family (e.g., almond, apricot, cherry, peach, and plum plants) have been taking special attention. Thus, the aim of this review is to report the recent advances in Rosaceae gum exudates. An emphasis is given for the formation mechanisms of these gums, their chemical composition, functional properties and structures, beneficial properties, as well as their food/non-food applications. PMID:26836615

  3. Linkage and candidate gene analysis of X-linked familial exudative vitreoretinopathy

    Shastry, B.S.; Hartzer, M.K. [Oakland Univ., Rochester, MI (United States); Hejtmancik, J.F. [National Eye Institute, Bethesda, MD (United States)] [and others

    1995-05-20

    Familial exudative vitreoretinopathy (FEVR) is a hereditary eye disorder characterized by avascularity of the peripheral retina, retinal exudates, tractional detachment, and retinal folds. The disorder is most commonly transmitted as an autosomal dominant trait, but X-linked transmission also occurs. To initiate the process of identifying the gene responsible for the X-linked disorder, linkage analysis has been performed with three previously unreported three- or four-generation families. Two-point analysis showed linkage to MAOA (Z{sub max} = 2.1, {theta}{sub max} = 0) and DXS228 (Z{sub max} = 0.5, {theta}{sub max} = 0.11), and this was further confirmed by multipoint analysis with these same markers (Z{sub max} = 2.81 at MAOA), which both lie near the gene causing Norrie disease. Molecular genetic analysis further reveals a missense mutation (R121W) in the third exon of the Norrie`s disease gene that perfectly cosegregates with the disease through three generations in one family. This mutation was not detected in the unaffected family members and six normal unrelated controls, suggesting that it is likely to be the pathogenic mutation. Additionally, a polymorphic missense mutation (H127R) was detected in a severely affected patient. 21 refs., 3 figs., 1 tab.

  4. Distribution of root exudates and mucilage in the rhizosphere: combining 14C imaging with neutron radiography

    Holz, Maire; Carminati, Andrea; Kuzyakov, Yakov

    2015-04-01

    Water and nutrients will be the major factors limiting food production in future. Plant roots employ various mechanisms to increase the access to limited soil resources. Low molecular weight organic substances released by roots into the rhizosphere increase nutrient availability by interactions with microorganisms, while mucilage improves water availability under low moisture conditions. Though composition and quality of these substances have intensively been investigated, studies on the spatial distribution and quantification of exudates in soil are scarce. Our aim was to quantify and visualize root exudates and mucilage distribution around growing roots using neutron radiography and 14C imaging depending on drought stress. Plants were grown in rhizotrons well suited for neutron radiography and 14C imaging. Plants were exposed to various soil water contents experiencing different levels of drought stress. The water content in the rhizosphere was imaged during several drying/wetting cycles by neutron radiography. The radiographs taken a few hours after irrigation showed a wet region around the root tips showing the allocation and distribution of mucilage. The increased water content in the rhizosphere of the young root segments was related to mucilage concentrations by parameterization described in Kroener et al. (2014). In parallel 14C imaging of root after 14CO2 labeling of shoots (Pausch and Kuzyakov 2011) showed distribution of rhizodeposits including mucilage. Three days after setting the water content, plants were labeled in 14CO2 atmosphere. Two days later 14C distribution in soil was imaged by placing a phosphor-imaging plate on the rhizobox. To quantify rhizodeposition, 14C activity on the image was related to the absolute 14C activity in the soil and root after destructive sampling. By comparing the amounts of mucilage (neutron radiography) with the amount of total root derived C (14C imaging), we were able to differentiate between mucilage and root

  5. Flavonoids and Strigolactones in Root Exudates as Signals in Symbiotic and Pathogenic Plant-Fungus Interactions

    Horst Vierheilig

    2007-07-01

    Full Text Available Secondary plant compounds are important signals in several symbiotic and pathogenic plant-microbe interactions. The present review is limited to two groups of secondary plant compounds, flavonoids and strigolactones, which have been reported in root exudates. Data on flavonoids as signaling compounds are available from several symbiotic and pathogenic plant-microbe interactions, whereas only recently initial data on the role of strigolactones as plant signals in the arbuscular mycorrhizal symbiosis have been reported. Data from other plant-microbe interactions and strigolactones are not available yet. In the present article we are focusing on flavonoids in plant-fungalinteractions such as the arbuscular mycorrhizal (AM association and the signaling between different Fusarium species and plants. Moreover the role of strigolactones in the AM association is discussed and new data on the effect of strigolactones on fungi, apart from arbuscular mycorrhizal fungi (AMF, are provided.

  6. A review of the influence of root-associating fungi and root exudates on the success of invasive plants

    Cindy Bongard

    2012-08-01

    Full Text Available Plant-fungal interactions are essential for understanding the distribution and abundance of plants species. Recently, arbuscular mycorrhizal fungal (AMF partners of non-indigenous invasive plants have been hypothesized to be a critical factor influencing the invasion processes. AMF are known to improve nutrient and moisture uptake, as well as disrupt parasitic and pathogenic microbes in the host plant. Such benefits may enable invaders to establish significant and persistent populations in environments previously dominated by natives. Coupling these findings with studies on invader pathogen-disrupting root exudates is not well documented in the literature describing plant invasion strategies. The interaction effects of altered AMF associations and the impact of invader root exudates would be more relevant than understanding the AMF dynamics or the phytochemistry of successful invaders in isolation, particularly given that AMF and root exudates can have a similar role in pathogen control but function quite differently. One means to achieve this goal is to assess these strategies concurrently by characterizing both the general (mostly pathogens or commensals and AM-specific fungal colonization patterns found in field collected root samples of successful invaders, native plants growing within dense patches of invaders, and native plants growing separately from invaders. In this review I examine the emerging evidence of the ways in which AMF-plant interactions and the production of defensive root exudates provide pathways to invasive plant establishment and expansion, and conclude that interaction studies must be pursued to achieve a more comprehensive understanding of successful plant invasion.

  7. Root exudate-induced alterations in Bacillus cereus cell wall contribute to root colonization and plant growth promotion.

    Swarnalee Dutta

    Full Text Available The outcome of an interaction between plant growth promoting rhizobacteria and plants may depend on the chemical composition of root exudates (REs. We report the colonization of tobacco, and not groundnut, roots by a non-rhizospheric Bacillus cereus (MTCC 430. There was a differential alteration in the cell wall components of B. cereus in response to the REs from tobacco and groundnut. Attenuated total reflectance infrared spectroscopy revealed a split in amide I region of B. cereus cells exposed to tobacco-root exudates (TRE, compared to those exposed to groundnut-root exudates (GRE. In addition, changes in exopolysaccharides and lipid-packing were observed in B. cereus grown in TRE-amended minimal media that were not detectable in GRE-amended media. Cell-wall proteome analyses revealed upregulation of oxidative stress-related alkyl hydroperoxide reductase, and DNA-protecting protein chain (Dlp-2, in response to GRE and TRE, respectively. Metabolism-related enzymes like 2-amino-3-ketobutyrate coenzyme A ligase and 2-methylcitrate dehydratase and a 60 kDa chaperonin were up-regulated in response to TRE and GRE. In response to B. cereus, the plant roots altered their exudate-chemodiversity with respect to carbohydrates, organic acids, alkanes, and polyols. TRE-induced changes in surface components of B. cereus may contribute to successful root colonization and subsequent plant growth promotion.

  8. CONJUGAL GENE TRANSFER IN THE RHIZOSPHERE OF WATER GRASS (ECHINOCHLORA CRUSGALLI): INFLUENCE OF ROOT EXUDATE AND BACTERIAL ACTIVITY

    The premise that genetic exchange is primarily localized in niches characterized by dense bacterial populations and high availability of growth substrates was tested by relating conjugal gene transfer of an RP4 derivative to availability of root exudates and bacterial metabolic a...

  9. Root exudates and leaf leachates of 19 medicinal plants of pakistan exhibit allelopathic potential

    Laboratory experiments were conducted to evaluate the allelopathic potential of root exudates and leaf leachates of 19 medicinal plants commonly used in Pakistan by plant box and sandwich methods, respectively. In sandwich method, lettuce seedlings were grown with the dry leaf leachates of the selected plant species in a growing media at the rate of 5, 10 and 50 mg dish-1 in a completely randomized design with three replications. Their effects on hypocotyl and radicle growth of the lettuce were recorded as a percentage of untreated control. Data was subjected for analysis of variance and treatment means were compared by Tukey's HSD test at p<0.05. Results indicated that allelopathic effects of the leaf leachates of all selected plant species on the hypocotyl and radicle elongations of the lettuce varied significantly in all concentrations used in experiments. The hypocotyl growth of the lettuce seedlings was affected from promotion (6.71% inhibition) caused by Phlaris minor to inhibition (78.40%) by Withania somnifera. Both species suppressed the radicle length from 33.69-93.30%. Leachates of W. somnifera and Sarcococca saligna exhibited strong inhibitory results in a concentration dependant manner. After the growth period of 50 days, root exudates of S. saligna appeared most detrimental (78.00% inhibition) to radicle growth of the lettuce seedling followed by W. somnifera (75.00%) when tested by plant box method. The results presented can be utilized as benchmark information for further joint research on the elucidation of chemicals involved in the allelopathy in nature and in the development of new and potent bioherbicides to combat environmental risk. (author)

  10. Combined intravitreal bevacizumab with phacoemulsification in visually significant cataract and visually significant exudative maculopathy

    Ahmad Mansour

    2011-01-01

    Full Text Available Purpose : We investigated the visual outcome of combined phacoemulsification with intravitreal bevacizumab, in eyes with dense cataract and visually significant exudative maculopathy. Materials and Methods : Prospective longitudinal pilot study of consecutive patients treated by two surgeons in 2006, using intravitreal bevacizumab at the end of phacoemulsification. The historical control group consisted of consecutive subjects with exudative maculopathy and dense cataract treated by the same surgeons with the help of phacoemulsification without intravitreal bevacizumab prior to 2006. Results : Thirty-one treated patients had the mean (SD logMar best corrected visual acuity improving from - 1.48 (0.50 preoperatively to - 0.67 (0.38 in the first postoperative week ( p < 0.001, to - 0.64 (0.40 in the first postoperative month ( p < 0.001, and to - 0.62 (0.42 ( p < 0.001 on the last follow-up (mean 4.2 months, range 1 - 9 months. Fourteen control patients had the mean (SD logMar best corrected visual acuity improving from - 1.78 (0.79 preoperatively, to - 0.91 (0.53 in the first postoperative week ( p < 0.001, to - 0.86 (0.45 in the first postoperative month ( p < 0.001, and to - 0.90 (0.47 ( p < 0.001 on the last follow- up (mean 19.6 months, range 1 - 49 months. Initial visual acuities, final visual acuities, and percentage of visual improvement at one month were all not significantly better in the intervention compared to the control group at one month. In the study group, the fovea was flattened at the one-month follow-up, by 90-diopter slit lamp examination and / or Optical coherence tomography. Conclusion : The combination of intravitreal bevacizumab and phacoemulsification is beneficial for maximal visual rehabilitation in the first postoperative month.

  11. Assessing bio-availability of metals in biosolid-amended soils: Root exudates and their effects on solubility of metals

    The existence of root exudates has been known to research scientists for a long time. Their role and function in plant nutrition and soil chemistry have only recently begun to be understood. The primary constituents of root exudates are low molecular weight organic acids that play an essential role in making the sparingly soluble soil Fe, P, and Zn available to plants. While root exudates are reasonably well characterized, the influence of environmental factors on their chemical composition and volume require further investigation. This study was initiated to investigate the role of root exudates on the solubilization and bioavailability of soil-borne heavy metals in biosolid-treated soils. Corn, wheat, canola, Sudan grass, chickpea, and Swiss chard were grown on standard and biosolid-treated sand media to characterize root exudates and evaluate the plants' metal-uptake patterns. Recent results indicate that: (i) the same organic acids were present over a 16-week growing season. However, the primary constituents of exudates from corn grown on standard sand media and biosolid-treated media were different. (ii) Metal concentrations in plant roots were considerably higher than those present in respective plant shoots, and plants grown in the biosolid-treated rooting medium had significantly higher concentrations of metals than those of the standard sand media at all stages of the growth. (iii) Based on mass present in the growth media and absorbed by corn, the phyto-availability of biosolid-borne metals were in the order: Cd > Ni = Zn > Cu = Pb > Cr. The availability of Mo was comparable to that of Cr. (iv) In the biosolidtreated growth medium, the uptake rates of Cd, Pb, and Zn by corn shoots (measured as mg of metal absorbed per g of biomass increment per unit time) were relatively constant over the active growing phase of the plants and were proportional to respective mass input of the metals. Work is in progress to define the role of root exudates on solubility

  12. Net production and consumption of fluorescent colored dissolved organic matter by natural bacterial assemblages growing on marine phytoplankton exudates.

    Romera-Castillo, Cristina; Sarmento, Hugo; Alvarez-Salgado, Xosé Antón; Gasol, Josep M; Marrasé, Celia

    2011-11-01

    An understanding of the distribution of colored dissolved organic matter (CDOM) in the oceans and its role in the global carbon cycle requires a better knowledge of the colored materials produced and consumed by marine phytoplankton and bacteria. In this work, we examined the net uptake and release of CDOM by a natural bacterial community growing on DOM derived from four phytoplankton species cultured under axenic conditions. Fluorescent humic-like substances exuded by phytoplankton (excitation/emission [Ex/Em] wavelength, 310 nm/392 nm; Coble's peak M) were utilized by bacteria in different proportions depending on the phytoplankton species of origin. Furthermore, bacteria produced humic-like substances that fluoresce at an Ex/Em wavelength of 340 nm/440 nm (Coble's peak C). Differences were also observed in the Ex/Em wavelengths of the protein-like materials (Coble's peak T) produced by phytoplankton and bacteria. The induced fluorescent emission of CDOM produced by prokaryotes was an order of magnitude higher than that of CDOM produced by eukaryotes. We have also examined the final compositions of the bacterial communities growing on the exudates, which differed markedly depending on the phytoplankton species of origin. Alteromonas and Roseobacter were dominant during all the incubations on Chaetoceros sp. and Prorocentrum minimum exudates, respectively. Alteromonas was the dominant group growing on Skeletonema costatum exudates during the exponential growth phase, but it was replaced by Roseobacter afterwards. On Micromonas pusilla exudates, Roseobacter was replaced by Bacteroidetes after the exponential growth phase. Our work shows that fluorescence excitation-emission matrices of CDOM can be a helpful tool for the identification of microbial sources of DOM in the marine environment, but further studies are necessary to explore the association of particular bacterial groups with specific fluorophores. PMID:21742918

  13. Root exudation and root development of lettuce (Lactuca sativa L.cv. Tizian as affected by different soils

    GünterNeumann

    2014-01-01

    Full Text Available Development and activity of plant roots exhibits high adaptive variability. Although it is well-documented, that physicochemical soil properties can strongly influence root morphology and root exudation, particularly under field conditions, a comparative assessment is complicated by the impact of additional factors, such as climate and cropping history. To overcome these limitations, in this study, field soils originating from an unique experimental plot system with three different soil types, which were stored at the same field site for ten years and exposed to the same agricultural management practice, were used for an investigation on effects of soil type on root development and root exudation. Lettuce (Lactuca sativa L. cv. Tizian was used as a model plant, grown under controlled environmental conditions in a minirhizotrone system equipped with root observation windows (rhizoboxes. Root exudates were collected by placing sorption filters onto the root surface followed by subsequent extraction and GC-MS profiling of the trapped compounds. Surprisingly, even in absence of external stress factors with known impact on root exudation, such as pH extremes, water and nutrient limitations/toxicities or soil structure effects (use of sieved soils, root growth characteristics (root length, fine root development as well as profiles of root exudates were strongly influenced by the soil type used for plant cultivation. The results coincided well with differences in rhizosphere bacterial communities, detected in field-grown lettuce plants cultivated on the same soils (Schreiter et al., this issue. The findings suggest that the observed differences may be the result of plant interactions with the soil-specific microbiomes.

  14. Staphylococcus hyicus virulence in relation to exudative epidermitis in pigs

    Wegener, Henrik Caspar; Andresen, Lars Ole; Bille-Hansen, Vivi

    1993-01-01

    Staphylococcus hyicus strains with different phage types, plasmid profiles, and antibiotic resistance patterns were isolated from piglets with exudative epidermitis. The strains could be divided into virulent strains, producing exudative epidermitis, and avirulent strains, producing no dermal...

  15. Effects of Grafting on Root Exudates of Cucumber and Rhizosphere Environment under Copper Stress

    Hua LI; Hongjun HE; Tengfei LI; Xin LI; Zikun ZHANG

    2013-01-01

    [Objective] This study to aimed to investigate the effects of Cu stress on root exudates and microbial activities in rhizosphere of grafted and ungrafted cucum-ber seedlings, and therefore to elucidate the microbial mechanism of grafting for in-creasing cucumber plants tolerance to Cu stress [Method] Four treatments: (1) un-grafted seedlings + test soil (U0); (2) ungrafted seedlings + test soil + CuSO4·5H2O (U1); (3) grafted seedlings + test soil (G0); (4) grafted seedlings + test soil + Cu-SO4·5H2O (G1) were set in the pot culture experiment. The contents of free amino acids, organic acids, phenolic acid and sugars, microbial population and enzyme ac-tivity in the four treatment were measured, respectively. [Result] The secretion of amino acids and organic acids were increased under Cu stress. The amino acids secretions of grafted seedlings roots were obviously higher than ungrafted seedlings except for Phe and Val. At the same time, the secretion of oxalic acid, malic acid, acetic acid, citric acid, cinnamic acid, ρ-hydroxybenzoic acid and benzoic acid of grafted seedlings were significantly higher than ungrafted seedlings as wel . There-fore, more Cu2+ were restricted in soil by chelating, complexing and precipitation with root exudates, and its toxicity was decreased. The soil microbial biomass C and N in grafted cucumber rhizosphere were significantly higher than those in ungrafted cu-cumber rhizosphere, whereas basal respiration and metabolic quotient were signifi-cantly lower. Under Cu stress, the numbers of actinomyces and nitrogen fixing bac-teria decreased and the number of fungi increased significantly, whereas there was no significant difference in amounts of bacteria. The numbers of bacteria, actino-myces, and nitrogen fixing bacteria in grafted cucumber rhizosphere were significant-ly higher than those in ungrafted cucumber rhizosphere, but the number of fungi was opposite. The activities of soil urease, phosphatase, sucrase and catalase in grafted

  16. Visual outcome of intravitreal ranibizumab for exudative age-related macular degeneration: timing and prognosis

    Canan H

    2014-01-01

    Full Text Available Handan Canan,1 Selçuk Sizmaz,2 Rana Altan-Yaycioğlu,1 Çağla Saritürk,3 Gürsel Yilmaz41Department of Ophthalmology, Adana Teaching and Medical Research Center, Baskent University School of Medicine, 2Department of Ophthalmology, Çukurova University School of Medicine, 3Department of Biostatistics, Adana Teaching and Medical Research Center, Baskent University School of Medicine, 4Department of Ophthalmology, Baskent University School of Medicine, Ankara, TurkeyPurpose: To describe 1-year clinical results of intravitreal ranibizumab treatment in patients with choroidal neovascularization secondary to exudative age-related macular degeneration (AMD and to evaluate whether early treatment is a predictive value for prognosis of the disease.Materials and methods: Clinical records were retrospectively reviewed of 104 eyes that underwent intravitreal ranibizumab therapy for exudative AMD. Patients were divided into two groups according to their symptom duration: group 1, <1 month; and group 2, 1–3 months. After three monthly injections, patients were examined monthly, and subsequent injections were performed as needed.Results: There were 43 female (48.9% and 45 males (51.1%. The follow-up time was 13.7±1.9 (12–19 months. The mean logarithm of minimum angle of resolution best-corrected visual acuity (BCVA improved significantly, from 0.45±0.639 at baseline to 0.08±0.267 at 12 months in group 1, and from 1.06±0.687 at baseline to 0.75±0.563 at 12 months in group 2. The increase in BCVA was statistically significant in group 1 (P=0.009. The mean central retinal thickness (CRT decreased significantly, from 355.13±119.93 µm at baseline to 250.85±45.48 µm at 12 months in group 1, and from 371.88±91.047 µm at baseline to 268.61±53.51 µm at 12 months in group 2. The decrease in CRT was statistically significant in group 1 (P=0.001.Conclusion: Intravitreal ranibizumab therapy was effective in significantly increasing mean BVCA and

  17. AUTOMATED DETECTION OF HARD EXUDATES IN FUNDUS IMAGES USING IMPROVED OTSU THRESHOLDING AND SVM

    Weiwei Gao

    2016-02-01

    Full Text Available One common cause of visual impairment among people of working age in the industrialized countries is Diabetic Retinopathy (DR. Automatic recognition of hard exudates (EXs which is one of DR lesions in fundus images can contribute to the diagnosis and screening of DR.The aim of this paper was to automatically detect those lesions from fundus images. At first,green channel of each original fundus image was segmented by improved Otsu thresholding based on minimum inner-cluster variance, and candidate regions of EXs were obtained. Then, we extracted features of candidate regions and selected a subset which best discriminates EXs from the retinal background by means of logistic regression (LR. The selected features were subsequently used as inputs to a SVM to get a final segmentation result of EXs in the image. Our database was composed of 120 images with variable color, brightness, and quality. 70 of them were used to train the SVM and the remaining 50 to assess the performance of the method. Using a lesion based criterion, we achieved a mean sensitivity of 95.05% and a mean positive predictive value of 95.37%. With an image-based criterion, our approach reached a 100% mean sensitivity, 90.9% mean specificity and 96.0% mean accuracy. Furthermore, the average time cost in processing an image is 8.31 seconds. These results suggest that the proposed method could be a diagnostic aid for ophthalmologists in the screening for DR.

  18. The past, present, and future of exudative age-related macular degeneration treatment

    Yoreh Barak

    2012-01-01

    Full Text Available Treatment of exudative age-related macular degeneration has been revolutionized within the last 6 years with the introduction of vascular endothelial growth factor neutralizing agents. Previously popular "destructive treatments," such as laser photocoagulation and photodynamic treatment have either been abandoned or used as an adjunct to pharmacotherapy. Despite the increase in vision after antivascular endothelial growth factor (VEGF agents, they require repetitive and costly intravitreal injections that also carry the inherit risks of infection, retinal tears, and detachment. Several new and more potent VEGF inhibitors are at different stages of development. The goal of evolving pharmacotherapy is to preserve the therapeutic effect while reducing or eliminating the discomfort of intravitreal drug delivery, as well as identify new therapeutic targets. Complement inhibitors, immunomodulators, integrin inhibitors are a few of the new class of drugs that are expected to be in our armamentarium soon. Current medications act to decrease leakage through abnormal subretinal choroidal vasculature and promote involution. However, these medications are only effective in treating the active stage of the choroidal neovascular membrane. Restoration of vision of a large number of patients with involuted choroidal neovascular membranes is warranted. For this purpose, tissue engineering techniques have been employed to reconstruct the subretinal anatomy. Discovery of biomarkers, pharmacogenetics, and very specific targeting holds the promise of increased potency and safety in the future.

  19. Water dynamics in the rhizosphere - a new model of coupled water uptake and mucilage exudation

    Kroener, Eva; Holz, Maire; Ahmed, Mutez; Zarebanadkouki, Mohsen; Bittelli, Marco; Carminati, Andrea

    2016-04-01

    The flow of water from soil to plant roots is affected by the narrow region of soil close to the roots, the so-called rhizosphere. The rhizosphere is influenced by mucilage, a polymeric gel exuded by roots that alters the hydraulic properties of the rhizosphere. Here we present a model that accounts for: (a) an increase in equilibrium water retention curve caused by the water holding capacity of mucilage, (b) a reduction of hydraulic conductivity at a given water content due to the higher viscosity of mucilage and (c) the swelling and shrinking dynamics by decoupling water content and water potential and introducing a non-equilibrium water retention curve. The model has been tested for mixtures of soil and mucilage and we applied it to simulate observations of previous experiments with real plants growing in soil that show evidences of altered hydraulic dynamics in the rhizosphere. Furthermore we present results about how the parameters of the model depend on soil texture and root age. Finally we couple our hydraulic model to a diffusion model of mucilage into the soil. Opposed to classical solute transport models here the water flow in the rhizosphere is affected by the concentration distribution of mucilage.

  20. Identification of novel KIF11 mutations in patients with familial exudative vitreoretinopathy and a phenotypic analysis.

    Li, Jia-Kai; Fei, Ping; Li, Yian; Huang, Qiu-Jing; Zhang, Qi; Zhang, Xiang; Rao, Yu-Qing; Li, Jing; Zhao, Peiquan

    2016-01-01

    KIF11 gene mutations cause a rare autosomal dominant inheritable disease called microcephaly with or without chorioretinopathy, lymphedema, or mental retardation (MCLMR). Recently, such mutations were also found to be associated with familial exudative vitreoretinopathy (FEVR). Here, we report 7 novel KIF11 mutations identified by targeted gene capture in a cohort of 142 probands with FEVR who were diagnosed in our clinic between March 2015 and November 2015. These mutations were: p.L171V, c.790-2A>C, p.Q525*, p.Q842*, p.S936*, p.L983fs and p.R1025G. Phenotypic analysis revealed that all of the affected probands had advanced FEVR (stage 4 or above). Three had microcephaly, and one had chorioretinopathy, which indicated a phenotypic overlap with MCLMR. Two mutations were also found in the families of the affected probands. One parent with a p.R1025G mutation had an avascular peripheral retina and abnormal looping vessels. However, one parent with p.L983fs had normal retina, which indicated incomplete penetration of the genotype. Our results further confirmed that KIF11 is causative of FEVR in an autosomal dominant manner. We also suggest the examination of MCLMR-like features, such as microcephaly, chorioretinopathy, for patients with FEVR and wide-field fundus photography for patients with MCLMR in future practice. PMID:27212378

  1. Aluminum resistance in common bean (Phaseolus vulgaris) involves induction and maintenance of citrate exudation from root apices.

    Rangel, Andrés Felipe; Rao, Idupulapati Madhusudana; Braun, Hans-Peter; Horst, Walter Johannes

    2010-02-01

    Two common bean (Phaseolus vulgaris L.) genotypes differing in aluminum (Al) resistance, Quimbaya (Al-resistant) and VAX-1 (Al-sensitive) were grown in hydroponics for up to 25 h with or without Al, and several parameters related to the exudation of organic acids anions from the root apex were investigated. Al treatment enhanced the exudation of citrate from the root tips of both genotypes. However, its dynamic offers the most consistent relationship between Al-induced inhibition of root elongation and Al accumulation in and exclusion from the root apices. Initially, in both genotypes the short-term (4 h) Al-injury period was characterized by the absence of citrate efflux independent of the citrate content of the root apices, and reduction of cytosolic turnover of citrate conferred by a reduced Nicotinamide adenine dinucleotide phosphate-isocitrate dehydrogenase (EC 1.1.1.42) activity. Transient recovery from initial Al stress (4-12 h) was found to be dependent mainly on the capacity to utilize internal citrate pools (Al-resistant genotype Quimbaya) or enhanced citrate synthesis [increased activities of NAD-malate dehydrogenase (EC 1.1.1.37) and ATP-phosphofructokinase (EC 2.7.1.11) in Al-sensitive VAX-1]. Sustained recovery from Al stress through citrate exudation in genotype Quimbaya after 24 h Al treatment relied on restoring the internal citrate pool and the constitutive high activity of citrate synthase (CS) (EC 4.1.3.7) fuelled by high phosphoenolpyruvate carboxylase (EC 4.1.1.31) activity. In the Al-sensitive genotype VAX-1 the citrate exudation and thus Al exclusion and root elongation could not be maintained coinciding with an exhaustion of the internal citrate pool and decreased CS activity. PMID:20053183

  2. LMWOA (low molecular weight organic acid) exudation by salt marsh plants: Natural variation and response to Cu contamination

    Mucha, Ana P.; Almeida, C. Marisa R.; Bordalo, Adriano A.; Vasconcelos, M. Teresa S. D.

    2010-06-01

    This work aimed to evaluate, in vitro, the capability of roots of two salt marsh plants to release low molecular weight organic acids (LMWOAs) and to ascertain whether Cu contamination would stimulate or not organic acids exudation. The sea rush Juncus maritimus and the sea-club rush Scirpus maritimus, both from the lower Douro river estuary (NW Portugal), were used. Plants were collected seasonally, four times a year in 2004, during low tide. After sampling, plant roots were washed for removal of adherent particles and immersed for 2 h in a solution that matched salinity (3) and pH (7.5) of the pore water from the same location to obtain plant exudates. In one of the seasons, similar experiments were carried out but spiking the solution with different amounts of Cu in order to embrace the range between 0 and 1600 nM. In the final solutions as well as in sediment pore water LMWOAs were determined by high performance liquid chromatography. Plants were able to release, in a short period of time, relatively high amounts of LMWOAs (oxalate, citrate, malate, malonate, and succinate). In the sediment pore water oxalate, succinate and acetate were also detected. Therefore, plant roots probably contributed to the presence of some of these organic compounds in pore water. Exudation differed between the plant species and also showed some seasonally variation, particularly for S. maritimus. The release of oxalate by J. maritimus increased with Cu increase in the media. However, exudation of the other LMWOAs did not seem to be stimulated by Cu contamination in the media. This fact is compatible with the existence of alternative internal mechanisms for Cu detoxification, as denoted by the fact that in media contaminated with Cu both plant species accumulated relatively high amounts (29-83%) of the initially dissolved Cu. This study expands our knowledge on the contribution of globally dominant salt marsh plants to the release of LMWOAs into the environment.

  3. Intravitreal treatment in patients with exudative age-related macular degeneration and visual acuity ≤ 0.05

    Koch, Raphael; Schmidt, Matthias; Gebauer, Sabine; Busse, Holger; Uhlig, Constantin E.

    2015-01-01

    Background To investigate intravitreal treatment efficiencies in patients suffering from exudative ARMD with a BCVA ≤ 0.05. Methods Retrospective analysis: Analysis parameters were lesion type, BCVA at baseline and at follow-up, the intravitreal drug used, and its application frequency. Patients were divided into: 1) following injections of bevacizumab, triamcinolone, their combination, or ranibizumab regardless of their lesion subtype, 2) or by lesion subtype. Statistical tests were performe...

  4. VARIATION IN RHIZOBIUM GROWTH DUE TO SEED AND ROOT EXUDATES RELEASED FROM GAMMA IRRADIATED GLYCINE MAX SEEDS

    In this study, seeds of Glycine max Giza 122 were irradiated with gamma rays from 60Co source at various doses (10 to 200 Gy), sterilized and soaked into an aerated solution of CaSO4 (1 mmol and pH 6.5). The capacities of the released seed exudates (SEs) and root exudates (REs) to promote Rhizobium leguminosarum growth were investigated as well as biochemical analysis of the exudates was carried out. SE of both control and gamma irradiated seeds resulted in a higher Rhizobium population and polysaccharide production than RE. Relative to control, the highly effective doses in Rhizobium growth and polysaccharide production were 25 and 200 Gy; the former was a promoter while the later was an inhibitor. HPLC analysis of soluble carbohydrates revealed the presence of glucose (Glu), rhamnose (Rha) and fructose (Fru) in the SE and RE. Protein content in SE was lower than that in RE; the highest values were due to 10 Gy and 25 Gy in SE and RE, respectively. Free amino acids content in SE was increased up to 25 Gy then decreased while RE was increased by increasing gamma doses from 10 to 200 Gy

  5. Chemical composition and functional properties of gum exudates from the trunk of the almond tree (Prunus dulcis).

    Mahfoudhi, N; Chouaibi, M; Donsì, F; Ferrari, G; Hamdi, S

    2012-06-01

    The physicochemical components and functional properties of the gum exudates from the trunk of the almond tree (Prunus dulcis) have been investigated, along with the emulsification and foaming properties. The gum exudates are composed on dry weight basis by 2.45% of proteins, 0.85% of fats and 92.36% of carbohydrates. The latter consist of arabinose, xylitol, galactose and uronic acid (46.8 : 10.9 : 35.5 : 6.0 mass ratio) with traces of rhamnose, mannose and glucose. Moreover, gum exudates are rich in minerals, such as sodium, potassium, magnesium, calcium and iron. The emulsifying capacity was studied for a 20% w/w olive oil in water emulsion as a function of gum concentration (from 3% to 12% w/w in the aqueous phase) as well as pH levels (from 3.0 to 10.0). The most stable and homogeneous emulsion was prepared with an 8% w/w aqueous almond gum solution at a pH between 5.0 and 8.0. In particular, for the same formulation, the emulsion processed by high pressure homogenization (5 passes at 200 MPa) resulted to be extremely stable under accelerated ageing, exhibiting no significant change in droplet size distribution for 14 days at 55 °C. All the tested systems exhibited an extremely low foaming capacity. PMID:22701057

  6. Application of a modified EDTA-mediated exudation technique and guttation fluid analysis for Potato spindle tuber viroid RNA detection in tomato plants (Solanum lycopersicum).

    Kovalskaya, Natalia; Owens, Robert; Baker, C Jacyn; Deahl, Kenneth; Hammond, Rosemarie W

    2014-03-01

    Potato spindle tuber viroid (PSTVd) is a small plant pathogenic circular RNA that does not encode proteins, replicates autonomously, and traffics systemically in infected plants. Long-distance transport occurs by way of the phloem; however, one report in the literature describes the presence of viroid RNA in the xylem ring of potato tubers. In this study, a modified method based on an EDTA-mediated phloem exudation technique was applied for detection of PSTVd in the phloem of infected tomato plants. RT-PCR, nucleic acid sequencing, and Southern blot analyses of RT-PCR products verified the presence of viroid RNA in phloem exudates. In addition, the guttation fluid collected from the leaves of PSTVd-infected tomato plants was analyzed revealing the absence of viroid RNA in the xylem sap. To our knowledge, this is the first report of PSTVd RNA detection in phloem exudates obtained by the EDTA-mediated exudation technique. PMID:24388932

  7. Solid phase extraction and metabolic profiling of exudates from living copepods

    Selander, Erik; Heuschele, Jan; Nylund, Göran M.; Pohnert, Georg; Pavia, Henrik; Bjærke, Oda; Pender-Healy, Larisa A.; Tiselius, Peter; Kiørboe, Thomas

    2016-01-01

    Copepods are ubiquitous in aquatic habitats. They exude bioactive compounds that mediate mate finding or induce defensive traits in prey organisms. However, little is known about the chemical nature of the copepod exometabolome that contributes to the chemical landscape in pelagic habitats. Here ...

  8. Findings and use of CT for pleural empyemas

    Chest radiographs and CT images of 25 patients with pleural empyemas were compared retrospectively with those of 20 patients with pleural exudates and transdudates in order to determine criteria for differential diagnosis and to define the place of CT in the diagnosis of pleural empyemas. The sign which was most suggestive of an empyema on a chest radiograph was an encapsulated effusion in an atypical position (18/25); this was found in only 4 out of 20 exudates and in none of the transudates. On CT, changes in the pleura, the subcostal tissues and the configuration and position of the fluid were suggestive of an empyema. In nearly all patients with a pleural empyema there was thickening and increased contrast uptake of the parietal pleura (22/25) and thickening and increased density oft the subcostal tissues (23/25). Usually, empyemas were encapsulated and biconvex (20/25). None of the patients with pleural transudates showed any of these changes. In the presence of some pleural exudates, pleural (14/20) or thoracic (11/20) changes were noted. In part, these changes were due to previous treatment (sclerotherapy) or tumour infiltration (7/20). An attempt to correlate the CT findings with changes in the pleura and subcostal tissues with the clinical empyema stages I-III, according to Light, showed that CT was unable to distinguish between early and late empyemas. Consequently, diagnostic aspiration remains necessary for correct treatment. (orig.)

  9. Arsenic Induced Phytate Exudation, and Promoted FeAsO4 Dissolution and Plant Growth in As-Hyperaccumulator Pteris vittata.

    Liu, Xue; Fu, Jing-Wei; Guan, Dong-Xing; Cao, Yue; Luo, Jun; Rathinasabapathi, Bala; Chen, Yanshan; Ma, Lena Q

    2016-09-01

    Arsenic hyperaccumulator Pteris vittata (PV) is efficient in taking up As and nutrients from As-contaminated soils. We evaluated the mechanisms used by PV to mobilize As and Fe by examining the impacts of As and root exudates on FeAsO4 solubilization, and As and Fe uptake in four plants: As-hyperaccumulators PV and Pteris multifida (PM), nonhyperaccumulator Pteris ensiformis (PE), and angiosperm plant tomato (Solanum lycopersicum). Phytate and oxalate were dominant in fern plants (>93%), which were 50-83, 15-42, and 0-32 mg kg(-1) phytate and 10-15, 7-26, and 4-12 mg kg(-1) oxalate for PV, PM, and PE respectively, with higher As inducing greater phytate exudation and no phytate being detected in tomato exudates. PV treated with phytate+FeAsO4 had higher As and Fe contents and larger biomass than phytate or FeAsO4 treatment, which were 340 vs 20 and 130 mg kg(-1) As in the fronds and 7900 vs 1600 and 4100 mg kg(-1) Fe in the roots. We hypothesized that As-induced phytate exudation helped PV to take up Fe and As from insoluble FeAsO4 and promoted PV growth. Our study suggests that phytate exudation may be special to fern plants, which may play an important role in enhancing As and nutrient uptake by plants, thereby increasing their efficiency in phytoremediation of As-contaminated soils. PMID:27483027

  10. Leachability of volatile fuel compounds from contaminated soils and the effect of plant exudates: A comparison of column and batch leaching tests.

    Balseiro-Romero, María; Kidd, Petra S; Monterroso, Carmen

    2016-03-01

    Volatile fuel compounds such as fuel oxygenates (FO) (MTBE and ETBE) and BTEX (benzene, toluene, ethylbenzene and xylene) are some of the most soluble components of fuel. Characterizing the leaching potential of these compounds is essential for predicting their mobility through the soil profile and assessing the risk of groundwater contamination. Plant root exudates can play an important role in the modification of contaminant mobility in soil-plant systems, and such effects should also be considered in leaching studies. Artificially spiked samples of A and B horizons from an alumi-umbric Cambisol were leached in packed-columns and batch experiments using Milli-Q water and plant root exudates as leaching agents. The leaching potential and rate were strongly influenced by soil-contaminant interactions and by the presence of root exudates. Organic matter in A horizon preferably sorbed the most non-polar contaminants, lowering their leaching potential, and this effect was enhanced by the presence of root exudates. On the other hand, the inorganic components of the B horizon, showed a greater affinity for polar molecules, and the presence of root exudates enhanced the desorption of the contaminants. Column experiments resulted in a more realistic protocol than batch tests for predicting the leaching potential of volatile organic compounds in dissimilar soils. PMID:26619047

  11. Comparison of the effect between pegaptanib and ranibizumab on exudative age-related macular degeneration with small lesion size

    Fujihara M

    2012-03-01

    Full Text Available Yoshihiro Nishimura1,2, Maiko Taguchi1, Takafumi Nagai1, Masashi Fujihara1,2, Shigeru Honda2, Mamoru Uenishi11Department of Ophthalmology, Mitsubishi Kobe Hospital, Kobe, Japan; 2Department of Surgery, Division of Ophthalmology, Kobe University Graduate School of Medicine, Kobe, JapanPurpose: To compare the effect of pegaptanib versus ranibizumab on exudative age-related macular degeneration (AMD with small lesion size.Methods: This is a retrospective study of 81 eyes from 78 patients with exudative AMD treated and followed up over 12 months. Patients with baseline best corrected visual acuity (BCVA under 20/400 and with a greatest linear dimension of lesion over 4500 µm were excluded from the study. Twenty-six eyes from 25 patients were treated with three consecutive intravitreal injections of pegaptanib (IVP group and 55 eyes from 54 patients were treated with three consecutive ranibizumab injections (IVR group. Each therapy was repeated as needed. The alteration in BCVA was evaluated in the IVP and IVR groups.Results: No differences were detected in baseline parameters between the IVP and IVR groups. The mean BCVA (logMAR at month 1, 3, 6 and 12 after the initial treatment was improved from baseline in the IVP group (-0.095, -0.17, -0.18 and -0.18, respectively and in the IVR group (-0.077, -0.15, -0.17 and -0.11, respectively, which was statistically significant. There was no difference in the change in mean BCVA between IVP and IVR groups at the same time periods.Conclusions: The visual outcome of IVP was equivalent with IVR in exudative AMD with small lesion size.Keywords: pegaptanib, ranibizumab, age-related macular degeneration, small lesion size

  12. Two mire species respond differently to enhanced ultraviolet-B radiation: effects on biomass allocation and root exudation

    Rinnan, Riikka Tiivi Mariisa; Gehrke, Carola; Michelsen, Anders

    2006-01-01

    •  Increased ultraviolet-B (UV-B) radiation arising from stratospheric ozone depletion may influence soil microbial communities via effects on plant carbon allocation and root exudation. •  Eriophorum angustifolium and Narthecium ossifragum plants, grown in peatland mesocosms consisting of Sphagnum...... peat, peat pore water and natural microbial communities, were exposed outdoors to enhanced UV-B radiation simulating 15% ozone depletion in southern Scandinavia for 8 wk. •  Enhanced UV-B increased rhizome biomass and tended to decrease the biomass of the largest root fraction of N...

  13. Histamine-induced airway mucosal exudation of bulk plasma and plasma-derived mediators is not inhibited by intravenous bronchodilators.

    Svensson, C; Alkner, U; Pipkorn, U; Persson, C G

    1994-01-01

    Experimental data suggest the possibility that common bronchodilators, such as the xanthines and beta 2-adrenoceptor agonists, may produce microvascular anti-permeability effects in the subepithelial microcirculation of the airways. In this study, we have examined the effect of bronchodilators given intravenously on exudation of different-sized plasma proteins (albumin and fibrinogen) and the generation of plasma-derived peptides (bradykinins) in human nasal airways challenged with histamine. In a double-blind, crossover, placebo-controlled and randomised trial, 12 normal volunteers were given i.v.infusions of terbutaline sulphate, theophylline and enprofylline to produce therapeutic drug levels. The effect of topical nasal provocation with histamine was closely followed by frequently nasal lavage with saline. The lavage fluid levels of albumin, fibrinogen and bradykinins increased significantly after each histamine provocation. The ratio of albumin-to-fibrinogen in plasma and the lavage fluid was 24 and 56, respectively, indicating that topical histamine provocation induced a largely non-sieved flux of macromolecules across the endothelial-epithelial barriers. The systemically administered drugs did not affect the nasal symptoms (sneezing, secretion and blockage), nor did they significantly reduce the levels of plasma proteins and plasma-derived mediators in the nasal lavage fluids. The present data suggest that systemic xanthines and beta 2-adrenoceptor agonists, at clinically employed plasma levels, may not affect the microvascular (and epithelial) exudative permeability and the bradykinin forming capacity of human airways. PMID:8005188

  14. [Comparison of the effects of laser and light-emitting diodes on lipid peroxidation in rat wound exudate].

    Klebanov, G I; Shuraeva, N Iu; Chichuk, T V; Osipov, A N; Vladimirov, Iu A

    2006-01-01

    The effect of laser and light-emitting diode radiation on lipid peroxidation in rat wound exudate was studied with the aim to compare the efficiency of coherent laser and incoherent light-emitting diode radiations. A model of aseptic wound in rat suggested by L.I. Slutskii was used. A He-Ne laser (632 nm) and a U-332B light-emitting diode were used in this study. The intensity of lipid peroxidation was estimated by the TBA assay. The antioxidative capacity of rat wound fluid was evaluated by means of chemiluminescent assays in two model systems: a) aqueous system with ABAP and luminol and b) in phospholipid liposome suspension with Fe2+ and cumarin. It was shown that exposure of rat wounds to both laser and light-emitting diode radiation decreased the concentration of TBA products and increased the antioxidative capacity of wound exudates, compared with the control group (without irradiation). The results obtained show that exposure of wounds to both laser and light-emitting diode irradiation causes a decrease in the oxidative stress in the rat wound fluid. No significant quantitative difference between the effects of laser and light-emitting diode irradiation was found. PMID:16637342

  15. Modeling of Heat Transfer and Interdendritic Strain for Exuded Surface Segregation Layer in the Direct Chill Casting of Aluminum Alloys

    El-Bealy, Mostafa Omar

    2016-02-01

    This investigation on the formation of exuded surface segregation layer " ESSL" is intended to provide experimental and simulated comparison to verify the model developed previously by El-Bealy. Preliminary verification and calibration of the previous 2D mathematical model are demonstrated by quantitative errors between the previous measurements and predictions of temperature and macrosegregation. Also, the results from these comparisons reveal that the errors are in the reasonable and within allowable limits. These comparisons lead to the fact that the exuded surface segregation layer mostly forms on the middle slice of broad sheet ingot face and in the early stages of mold zone. The model predictions point out also that the different interdendritic strain hypotheses associated with fluctuations of mold cooling conditions. This affects the interdendritic liquid flow between the equiaxed crystals which influences the severity of ESSL formation and its macrosegregation level. The mechanism of ESSL with heat flow and interdendritic strain generation has been analyzed and discussed. The quantitative comparisons between the pervious experimental results and numerical simulation in this investigation reveal also several solutions to prevent this defect for future work.

  16. The role of organic acids exuded from roots in phosphorus nutrition and aluminium tolerance in acidic soils

    Soil acidity is a major problem of large areas of arable land on a global scale. Many acid soils are low in plant-available phosphorus (P) or are highly P-fixing, resulting in poor plant growth. In addition, aluminium (Al) is soluble in acid soils in the toxic Al3+ form, which also reduces plant growth. There is considerable evidence that both P deficiency and exposure to Al3+ stimulate the efflux of organic acids from roots of a range of species. Organic acids such as citrate, malate and oxalate are able to desorb or solubilise fixed soil P, making it available for plant uptake. Organic acids also chelate Al3+ to render it non-toxic, and are, therefore, involved in Al tolerance mechanisms. In this review, we discuss the literature on the role of organic acids exuded from roots in improving plant P uptake and Al-tolerance in acid soils. Research is now attempting to understand how P deficiency or exposure to Al3+ activates or induces organic acid efflux at the molecular level, with the aim of improving P acquisition and Al tolerance by conventional plant breeding and by genetic engineering. At the agronomic level, it is desirable that existing crop and pasture plants with enhanced soil-P uptake and tolerance to Al due to organic acid exudation are integrated into farming systems. (author)

  17. Rhizosphere priming effect on soil organic carbon decomposition under plant species differing in soil acidification and root exudation.

    Wang, Xiaojuan; Tang, Caixian; Severi, Julia; Butterly, Clayton R; Baldock, Jeff A

    2016-08-01

    Effects of rhizosphere properties on the rhizosphere priming effect (RPE) are unknown. This study aimed to link species variation in RPE with plant traits and rhizosphere properties. Four C3 species (chickpea, Cicer arietinum; field pea, Pisum sativum; wheat, Triticum aestivum; and white lupin, Lupinus albus) differing in soil acidification and root exudation, were grown in a C4 soil. The CO2 released from soil was trapped using a newly developed NaOH-trapping system. White lupin and wheat showed greater positive RPEs, in contrast to the negative RPE produced by chickpea. The greatest RPE of white lupin was in line with its capacity to release root exudates, whereas the negative RPE of chickpea was attributed to its great ability to acidify rhizosphere soil. The enhanced RPE of field pea at maturity might result from high nitrogen deposition and release of structural root carbon components following root senescence. Root biomass and length played a minor role in the species variation in RPE. Rhizosphere acidification was shown to be an important factor affecting the magnitude and direction of RPE. Future studies on RPE modelling and mechanistic understanding of the processes that regulate RPE should consider the effect of rhizosphere pH. PMID:27101777

  18. Benzo[a]pyrene co-metabolism in the presence of plant root extracts and exudates: Implications for phytoremediation

    Benzo[a]pyrene, a high molecular weight (HMW) polycyclic aromatic hydrocarbon (PAH) was removed from solution by Sphingomonas yanoikuyae JAR02 while growing on root products as a primary carbon and energy source. Plant root extracts of osage orange (Maclura pomifera), hybrid willow (Salix albaxmatsudana), or kou (Cordia subcordata), or plant root exudates of white mulberry (Morus alba) supported 15-20% benzo[a]pyrene removal over 24 h that was similar to a succinate grown culture and an unfed acetonitrile control. No differences were observed between the different root products tested. Mineralization of 14C-7-benzo[a]pyrene by S. yanoikuyae JAR02 yielded 0.2 to 0.3% 14CO2 when grown with plant root products. Collectively, these observations were consistent with field observations of enhanced phytoremediation of HMW PAH and corroborated the hypothesis that co-metabolism may be a plant/microbe interaction important to rhizoremediation. However, degradation and mineralization was much less for root product-exposed cultures than salicylate-induced cultures, and suggested the rhizosphere may not be an optimal environment for HMW PAH degradation by Sphingomonas yanoikuyae JAR02. - Bacterial benzo[a]pyrene cometabolism, a plant-microbe interaction affecting polycyclic aromatic hydrocarbon phytoremediation was demonstrated with Sphingomonas yanoikuyae JAR02 that utilized plant root extracts and exudates as primary substrates

  19. Effects of root exudates of bivalent transgenic cotton (Bt+CpTI) plants on antioxidant proteins and growth of conventional cotton (Xinluhan 33).

    Wu, Hong-Sheng; Shi, Xue; Li, Ji; Wu, Tian-Yu; Ren, Qian-Qi; Zhang, Zhen-Hua; Wang, Ming-Yan; Shang, Xiao-Xia; Liu, Yan; Xiao, Song-Hua

    2016-01-01

    A greenhouse experiment was conducted to assess the adverse impact of transgenic cotton on ecosystem and environment via effect of transgenic Bt+CpTI cotton root exudates on growth and antioxidant activity of conventional parental cotton. Results showed elevated reductive and oxidative species activities in the leaves of conventional parental cotton seedlings treated with varying concentrations of transgenic cotton root exudates. Compared to control, 14.9% to 39.9% increase in catalase, 8.8% to 114% increase in for peroxidase, 21.3% to 59.7% increase in phenylalanine ammonia-lyase and 5.8 to 19.5 fold in ascorbate specific peroxidase was observed. However, biomass and height of conventional cotton seedlings were not affected by any concentration of transgenic cotton root exudates. These results suggested that cultivation of transgenic Bt+CpTI cotton plants poses little risk to conventional parental cotton based on their root interactions. PMID:26930855

  20. A mathematical model of sap exudation in maple trees governed by ice melting, gas dissolution and osmosis

    Ceseri, Maurizio

    2013-01-01

    We develop a mathematical model for sap exudation in a maple tree that is based on a purely physical mechanism for internal pressure generation in trees in the leafless state. There has been a long-standing controversy in the tree physiology literature over precisely what mechanism drives sap exudation, and we aim to cast light on this issue. Our model is based on the work of Milburn and O'Malley [Can. J. Bot., 62(10):2101-2106, 1984] who hypothesized that elevated sap pressures derive from compressed gas that is trapped within certain wood cells and subsequently released when frozen sap thaws in the spring. We also incorporate the extension of Tyree [in Tree Sap, pp. 37-45, eds. M. Terazawa et al., Hokkaido Univ. Press, 1995] who argued that gas bubbles are prevented from dissolving because of osmotic pressure that derives from differences in sap sugar concentrations and the selective permeability of cell walls. We derive a system of differential-algebraic equations based on conservation principles that is u...

  1. Automatic Detection of Retinal Exudates using a Support Vector Machine

    Nualsawat HIRANSAKOLWONG; Ekkarat POTHIRUK; Kittipol WISAENG

    2013-01-01

    Retinal exudates are among the preliminary signs of diabetic retinopathy, a major cause of vision loss in diabetic patients. Correct and efficient screening of exudates is very expensive in professional time and may cause human error. Nowadays, the digital retinal image is frequently used to follow-up and diagnoses eye diseases. Therefore, the retinal image is crucial and essential for experts to detect exudates. Unfortunately, it is a normal situation that retinal images in Thailand are poor...

  2. Lauric acid in crown daisy root exudate potently regulates root-knot nematode chemotaxis and disrupts Mi-flp-18 expression to block infection.

    Dong, Linlin; Li, Xiaolin; Huang, Li; Gao, Ying; Zhong, Lina; Zheng, Yuanyuan; Zuo, Yuanmei

    2014-01-01

    Tomato (Solanum lycopersicum) crops can be severely damaged due to parasitism by the root-knot nematode (RKN) Meloidogyne incognita, but are protected when intercropped with crown daisy (Chrysanthemum coronarium L.). Root exudate may be the determining factor for this protection. An experiment using pots linked by a tube and Petri dish experiments were undertaken to confirm that tomato-crown daisy intercropping root exudate decreased the number of nematodes and alleviated nematode damage, and to determine crown daisy root exudate-regulated nematode chemotaxis. Following a gas chromatography-mass spectrometry assay, it was found that the intercropping protection was derived from the potent bioactivity of a specific root exudate component of crown daisy, namely lauric acid. The Mi-flp-18 gene, encoding an FMRFamide-like peptide neuromodulator, regulated nematode chemotaxis and infection by RNA interference. Moreover, it was shown that lauric acid acts as both a lethal trap and a repellent for M. incognita by specifically regulating Mi-flp-18 expression in a concentration-dependent manner. Low concentrations of lauric acid (0.5-2.0mM) attract M. incognita and consequently cause death, while high concentrations (4.0mM) repel M. incognita. This study elucidates how lauric acid in crown daisy root exudate regulates nematode chemotaxis and disrupts Mi-flp-18 expression to alleviate nematode damage, and presents a general methodology for studying signalling systems affected by plant root exudates in the rhizosphere. This could lead to the development of economical and feasible strategies for controlling plant-parasitic nematodes, and provide an alternative to the use of pesticides in farming systems. PMID:24170741

  3. Non-targeted profiling of semi-polar metabolites in Arabidopsis root exudates uncovers a role for coumarin secretion and lignification during the local response to phosphate limitation.

    Ziegler, Jörg; Schmidt, Stephan; Chutia, Ranju; Müller, Jens; Böttcher, Christoph; Strehmel, Nadine; Scheel, Dierk; Abel, Steffen

    2016-03-01

    Plants have evolved two major strategies to cope with phosphate (Pi) limitation. The systemic response, mainly comprising increased Pi uptake and metabolic adjustments for more efficient Pi use, and the local response, enabling plants to explore Pi-rich soil patches by reorganization of the root system architecture. Unlike previous reports, this study focused on root exudation controlled by the local response to Pi deficiency. To approach this, a hydroponic system separating the local and systemic responses was developed. Arabidopsis thaliana genotypes exhibiting distinct sensitivities to Pi deficiency could be clearly distinguished by their root exudate composition as determined by non-targeted reversed-phase ultraperformance liquid chromatography electrospray ionization quadrupole-time-of-flight mass spectrometry metabolite profiling. Compared with wild-type plants or insensitive low phosphate root 1 and 2 (lpr1 lpr2) double mutant plants, the hypersensitive phosphate deficiency response 2 (pdr2) mutant exhibited a reduced number of differential features in root exudates after Pi starvation, suggesting the involvement of PDR2-encoded P5-type ATPase in root exudation. Identification and analysis of coumarins revealed common and antagonistic regulatory pathways between Pi and Fe deficiency-induced coumarin secretion. The accumulation of oligolignols in root exudates after Pi deficiency was inversely correlated with Pi starvation-induced lignification at the root tips. The strongest oligolignol accumulation in root exudates was observed for the insensitive lpr1 lpr2 double mutant, which was accompanied by the absence of Pi deficiency-induced lignin deposition, suggesting a role of LPR ferroxidases in lignin polymerization during Pi starvation. PMID:26685189

  4. Automated detection of exudates for diabetic retinopathy screening

    Automated image analysis is being widely sought to reduce the workload required for grading images resulting from diabetic retinopathy screening programmes. The recognition of exudates in retinal images is an important goal for automated analysis since these are one of the indicators that the disease has progressed to a stage requiring referral to an ophthalmologist. Candidate exudates were detected using a multi-scale morphological process. Based on local properties, the likelihoods of a candidate being a member of classes exudate, drusen or background were determined. This leads to a likelihood of the image containing exudates which can be thresholded to create a binary decision. Compared to a clinical reference standard, images containing exudates were detected with sensitivity 95.0% and specificity 84.6% in a test set of 13 219 images of which 300 contained exudates. Depending on requirements, this method could form part of an automated system to detect images showing either any diabetic retinopathy or referable diabetic retinopathy

  5. Automated detection of exudates for diabetic retinopathy screening

    Fleming, Alan D [Biomedical Physics, University of Aberdeen, Aberdeen, AB25 2ZD (United Kingdom); Philip, Sam [Diabetes Retinal Screening Service, David Anderson Building, Foresterhill Road, Aberdeen, AB25 2ZP (United Kingdom); Goatman, Keith A [Biomedical Physics, University of Aberdeen, Aberdeen, AB25 2ZD (United Kingdom); Williams, Graeme J [Diabetes Retinal Screening Service, David Anderson Building, Foresterhill Road, Aberdeen, AB25 2ZP (United Kingdom); Olson, John A [Diabetes Retinal Screening Service, David Anderson Building, Foresterhill Road, Aberdeen, AB25 2ZP (United Kingdom); Sharp, Peter F [Biomedical Physics, University of Aberdeen, Aberdeen, AB25 2ZD (United Kingdom)

    2007-12-21

    Automated image analysis is being widely sought to reduce the workload required for grading images resulting from diabetic retinopathy screening programmes. The recognition of exudates in retinal images is an important goal for automated analysis since these are one of the indicators that the disease has progressed to a stage requiring referral to an ophthalmologist. Candidate exudates were detected using a multi-scale morphological process. Based on local properties, the likelihoods of a candidate being a member of classes exudate, drusen or background were determined. This leads to a likelihood of the image containing exudates which can be thresholded to create a binary decision. Compared to a clinical reference standard, images containing exudates were detected with sensitivity 95.0% and specificity 84.6% in a test set of 13 219 images of which 300 contained exudates. Depending on requirements, this method could form part of an automated system to detect images showing either any diabetic retinopathy or referable diabetic retinopathy.

  6. THE CLINICAL APPLICATIONS FOR AUTOMATIC DETECTION OF EXUDATES

    K. Wisaeng; N. Hiransakolwong; E. Pothiruk

    2014-01-01

    Nowadays, the retinal imaging technology has been widely used for segmenting and detecting the exudates in diabetic retinopathy patients. Unfortunately, the retinal images in Thailand are poor-quality images. Therefore, detecting of exudates in a large number by screening programs, are very expensive in professional time and may cause human error. In this study, the clinical applications for detection of exudates from the poor quality retinal image are presented. An application incorporating ...

  7. Guaianolides and a seco-Eudesmane from the Resinous Exudates of Cushion Bush (Leucophyta brownii) and Evaluation of Their Cytostatic and Anti-inflammatory Activity

    Hyldgaard, Mette G; Purup, Stig; Bond, Andrew D;

    2015-01-01

    A detailed phytochemical investigation of a dichloromethane extract of the resinous exudates of the cushion bush plant (Leucophyta brownii) resulted in the isolation of the new 8,12-guaianolides leucophytalins A (5) and B (6), the new 1,10-seco-eudesmane leucophytalin C (10), six rare 8,12-guaian...... (+)-germacrene A, and a biosynthetic pathway is proposed for these sesquiterpenoids....

  8. Medium-term response of microbial community to rhizodeposits of white clover and ryegrass and tracing of active processes induced by 13C and 15N labelled exudates

    Kusliene, Gedrime; Rasmussen, Jim; Kuzyakov, Yakov; Eriksen, Jørgen

    2014-01-01

    actinomycetes was unaffected by plant species, but pool of Gram-negative and Gram-positive bacteria was greater under white clover at the 10 percent significance level. In the short term, microorganisms more actively utilised fresh exudates (13C-labelled) of ryegrass than of white clover. We expected ryegrass...

  9. Response of Nodularia spumigena to pCO2 – Part 2: Exudation and extracellular enzyme activities

    M. Nausch

    2012-04-01

    Full Text Available The filamentous and diazotrophic cyanobacterium Nodularia spumigena plays a major role in the productivity of the Baltic Sea as it forms extensive blooms regularly. Under phosphorus limiting conditions Nodularia spumigena has a high enzyme affinity for dissolved organic phosphorus (DOP by production and release of alkaline phosphatase. Additionally, it is able to degrade proteinaceous compounds by expressing the extracellular enzyme leucine aminopeptidase. As atmospheric CO2 concentrations are increasing, we expect marine phytoplankton to experience changes in several environmental parameters including pH, temperature, and nutrient availability. The aim of this study was to investigate the combined effect of CO2-induced changes in seawater carbonate chemistry and of phosphate deficiency on the exudation of organic matter, and its subsequent recycling by extracellular enzymes in a Nodularia spumigena culture. Batch cultures of Nodularia spumigena were grown for 15 days aerated with three different pCO2 levels corresponding to values from glacial periods to future values projected for the year 2100. Extracellular enzyme activities as well as changes in organic and inorganic compound concentrations were monitored. CO2 treatment–related effects were identified for cyanobacterial growth, which in turn was influencing exudation and recycling of organic matter by extracellular enzymes. Biomass production was increased by 56.5% and 90.7% in the medium and high pCO2 treatment, respectively, compared to the low pCO2 treatment and simultaneously increasing exudation. During the growth phase significantly more mucinous substances accumulated in the high pCO2 treatment reaching 363 μg Gum Xanthan eq l−1 compared to 269 μg Gum Xanthan eq l−1 in the low pCO2 treatment. However, cell-specific rates did not change. After phosphate depletion, the acquisition of P from DOP by alkaline phosphatase was significantly enhanced. Alkaline phosphatase activities

  10. Artificial Root Exudate System (ARES): a field approach to simulate tree root exudation in soils

    Lopez-Sangil, Luis; Estradera-Gumbau, Eduard; George, Charles; Sayer, Emma

    2016-04-01

    The exudation of labile solutes by fine roots represents an important strategy for plants to promote soil nutrient availability in terrestrial ecosystems. Compounds exuded by roots (mainly sugars, carboxylic and amino acids) provide energy to soil microbes, thus priming the mineralization of soil organic matter (SOM) and the consequent release of inorganic nutrients into the rhizosphere. Studies in several forest ecosystems suggest that tree root exudates represent 1 to 10% of the total photoassimilated C, with exudation rates increasing markedly under elevated CO2 scenarios. Despite their importance in ecosystem functioning, we know little about how tree root exudation affect soil carbon dynamics in situ. This is mainly because there has been no viable method to experimentally control inputs of root exudates at field scale. Here, I present a method to apply artificial root exudates below the soil surface in small field plots. The artificial root exudate system (ARES) consists of a water container with a mixture of labile carbon solutes (mimicking tree root exudate rates and composition), which feeds a system of drip-tips covering an area of 1 m2. The tips are evenly distributed every 20 cm and inserted 4-cm into the soil with minimal disturbance. The system is regulated by a mechanical timer, such that artificial root exudate solution can be applied at frequent, regular daily intervals. We tested ARES from April to September 2015 (growing season) within a leaf-litter manipulation experiment ongoing in temperate deciduous woodland in the UK. Soil respiration was measured monthly, and soil samples were taken at the end of the growing season for PLFA, enzymatic activity and nutrient analyses. First results show a very rapid mineralization of the root exudate compounds and, interestingly, long-term increases in SOM respiration, with negligible effects on soil moisture levels. Large positive priming effects (2.5-fold increase in soil respiration during the growing

  11. Phloem exudation studies in selected woody trees

    Costello, L.R.

    1980-10-01

    Chelating agents, particularly EDTA, were tested for their effectiveness in enhancing the exudation of phloem sugars from selected woody tree species. Of the species selected, Fraxinus uhdei (Evergreen Ash) proved most useful for exudation studies. Experiments using /sup 14/C labelled, excised leaflets of F. uhdei demonstrated that exudation was enhanced approximately 9-fold by a 2.0 mM EDTA treatment. An analysis of labelled products in the treatment solution showed that over 90% of label appeared in oligosaccharides and sucrose. These findings suggested that the sugars released into EDTA treatment solutions were principally derived from phloem sieve elements. Electron microscope studies of the fine structure of sieve plate pores after treatment with EDTA or H/sub 2/O showed substantially less callose appearing in sieve plates of leaflets treated with EDTA. It was proposed that EDTA enhances exudation by inhibiting or reducing callose formation in sieve plate pores. Subsequent experiments demonstrated that EDTA was effective in promoting exudation from whole plant specimens of F. uhdei as well as from excised leaflets. (MHR)

  12. Comparative Study of Elaeis Guiniensis Exudates (Palm Wine as a Corrosion Inhibitor for Mild Steel in Acidic and Basic Solutions

    S.C. Nwigbo

    2012-01-01

    Full Text Available This study has explored the possibility of using a typical plant extract other than the use of conventional materials as corrosion inhibitor. Elaeis guinensis exudates (Palm wine, which contains carbonyl groups, double bonds and triple bonds as shown by the FTIR, Gas chromatography-mass spectrometry and phytochemical tests is a one of good natural materials as corrosion inhibitor. This paper was focused on the behaviour of palm wine as corrosion inhibitor for mild steel in (0.1 and 0.5 M H2SO4 and NaOH solutions at 303 and 333 K temperatures and inhibitor concentrations using weight loss measurement. Results showed that weight loss decreases as concentration of both solutions studied increase. The inhibitor performs better under the basic solution compared to the acidic solution. The kinetics results showed that activation energy increases as temperature and inhibitors concentration increase. Palm wine inhibitor adsorbed on the surface of mild steel through physical adsorption.

  13. Differentiation and distribution of three types of exfoliative toxin produced by Staphylococcus hyicus from pigs with exudative epidermitis

    Andresen, Lars Ole

    1998-01-01

    were antigenically distinct. The three toxins were designated ExhA, ExhB and ExhC. From 60 diseased pigs, each representing an outbreak of exudative epidermitis, a total of 584 isolates of S. hl icus were phage typed and tested for production of exfoliative toxin. ExhA-, ExhB- and ExhC-producing S......Exfoliative toxins of approximately 30 kDa produced by Staphylococcus hyicus strains NCTC 10350, 1289D-88 and 842A-88 were purified and specific polyclonal antisera were raised against each of the toxins. It was shown by immunoblot analysis and ELISA that three exfoliative toxins from S. hyicus....... hyicus isolates were found in 12 (20%), 20 (33%) and 11 (18%); respectively, of the 60 pig herds investigated. Production of the different types of exfoliative toxin was predominantly associated with certain phage groups. However. toxin production was found in all of the six phage groups defined by the...

  14. Differentiation and distribution of three types of exfoliative toxin produced by Staphylococcus hyicus from pigs with exudative epidermitis

    Andresen, Lars Ole

    1998-01-01

    were antigenically distinct. The three toxins were designated ExhA, ExhB and ExhC. From 60 diseased pigs, each representing an outbreak of exudative epidermitis, a total of 584 isolates of S. hl icus were phage typed and tested for production of exfoliative toxin. ExhA-, ExhB- and ExhC-producing S....... hyicus isolates were found in 12 (20%), 20 (33%) and 11 (18%); respectively, of the 60 pig herds investigated. Production of the different types of exfoliative toxin was predominantly associated with certain phage groups. However. toxin production was found in all of the six phage groups defined by the...... phage typing system. Some changes in the distribution of isolates between phage groups were observed when the results of this study were compared to previous investigations. In this study two new antigenically distinct exfoliative toxins were isolated and tools for in vitro detection of toxin producing...

  15. Influence of dichloromethylene bisphosphonate on the in vitro phagocytosis of hydroxyapatite particles by rat peritoneal exudate cells: an electron microscopic and chemiluminescence study.

    Hyvönen, P M; Kowolik, M J

    1992-01-01

    Transmission electron microscopy and standard chemiluminescence assays were used to investigate the in vivo effect of dichloromethylene bisphosphonate (clodronate) on the phagocytosis of pure hydroxyapatite particles by rat peritoneal macrophages and the production of chemiluminescence by the peritoneal exudate cells. Hydroxyapatite (control) and a hydroxyapatite/clodronate suspension (28 mumol clodronate per gram of hydroxyapatite, experimental) were injected into the peritoneum of rats, the...

  16. Early and exudative age-related macular degeneration is associated with increased plasma levels of soluble TNF receptor II

    Faber, Carsten; Jehs, Tina; Juel, Helene Baek; Singh, Amardeep; Falk, Mads Krüger; Sørensen, Torben Lykke; Nissen, Mogens Holst

    2015-01-01

    PURPOSE: We have recently identified homeostatic alterations in the circulating T cells of patients with age-related macular degeneration (AMD). In cultures of retinal pigment epithelial cells, we have demonstrated that T-cell-derived cytokines induced the upregulation of complement, chemokines and...... other proteins implicated in AMD pathogenesis. The purpose of this study was to test whether increased plasma levels of cytokines were present in patients with AMD. METHODS: We conducted a case-control study. Age-related macular degeneration status was assessed using standardized multimodal imaging...... forms of AMD and 74 controls. Significantly increased levels of sTNFRII were observed in patients with early or exudative AMD (p < 0.01). After adjusting for CFH Y402H genotype, age, sex and smoking history, the level of sTNFRII remained a significant predictor for prevalence of AMD with odds ratios at...

  17. INFLUENCE OF ROOT EXUDATES AND BACTERIAL METABOLIC ACTIVITY ON APPARENT CONJUGAL GENE TRANSFER FREQUENCIES IN THE RHIZOSPHERE OF WATER GRASS (ECHINOCLORA CRUSGALLI)

    The premise that genetic exchange is primarily localized in niches characterized by dense bacterial populations and high availability of growth substrates was tested by relating conjugal gene transfer of an RP4 derivative to availability of root exudates and bacterial metabolic a...

  18. Clinical value of detection of malignant ascites and thoracic exudate by means of six tumor-markers

    Objective: To study the clinical value of six potential tumor markers including serums CA125, CYFRA21-1, CA-50, CA15-3, HCG, β-HCG. These were determined in effusions of malignant ascites and hydrothorax of 170 patients, with cellular examination as control. Methods: Using IRMA. Results: The data of our experiments revealed that of all six tumor-markers, CA125 was the highest in positive rate as well as concordance rate with cytology examination. In or- der CA125, CA-50, CA15-3, CYFRA21-1, β-HCG. It was valuable to point out that the specificity of HCG and β-HCG was very strong and there was no false positivity had yet been found with them. Though their positivity was not so high as that of CA125. Have to higher specificity of detection of malignant ascites by CYFRA21-1. Conclusions: It suggested that + CYFRA21-1 should be the preferred choice in diagnosing malignant hydrothorax next + CA-50,CYFRA21-1 +CA-50; for malignant ascites as well, CA125 + β-HCG determination is just as good, next CA125 + CYFRA21-1. We believe that when a clear diagnosis of a primary focus of cancer is made clinically, or a malignant ascites or thoracic exudate come highly under suspicion, the diagnosis of malignancy of the ascites or thoracic exudate can be established even though the exfoliative cells, provided the detection by tumor-markers, it has got one of the following results: the roles of tumor-markers determination in malignant serous effusions, two of CA125, CYFRA21-1. CA15-3 and CA-50 markers are positive; anyone of the above markers plus HCG or β-HCG positivity; both HCG and β-HCG or CA15-3 are positive. (author)

  19. Determination of Organi Acids in Root Exudates by High Performance Liquid Chromatorgraphy:Ⅰ.Develop—ment and Assessment of Chromatographic Conditions

    SHENJIANBO; ZHANGFUSUO; 等

    1998-01-01

    Methods for determining niene low molecular-weight oragnic acids in root exudates were developed by using reversed-phase high performance liquied chromatography with UV (ultraviolet) detection at 214 nm. The mobile phase was 18 mmol L-1 kH2PO4 adjusted to pH 2.25 with phosporic acid nd the flow rate was 0.3 mL min-1,The analytical column was a reversed-phase silica based C-18 column( shim-pack CLC-ODS).The root exudates were collected through submerging the whole root system into aerated deionized water for 2 hours ,The filtered exudate solutions were concentrated to dryness by rotary evaporation at 40℃,dissolved in 10 mL mobile phase.The chromatoraphic conditions of organic acid determination were analyzed.The results showed that there was a high selectivity and sensitivity in the organic acid determination by reversed-phase high performance liquid chromatography.Coefficients of variation for organic acied determination were lower than 10% except lactic acid .The recoveries were consistently between 80.1% to 108.3% .Detection limits were approximately 0.05 to 4.5 mg L-1 for organic acids except succinic acid with the detection limit of 7.0 mg L-1 .Phosphorus deficiency may contribute to the release of organic acids in soybean root exudates especially malic,lactic and citric acids.

  20. EFFICACY OF PLEURAL FLUID ADENOSINE DEAMINASE AND C -REACTIVE PROTEIN LEVELS IN EARLY DIFFERENTIAL DIAGNOSIS OF P LEURAL EFFUSION.

    Aliya

    2013-05-01

    Full Text Available ABSTRACT: - CONTEXT: Pleural effusion occurs secondary to various disea ses. Common causes of exudative effusion are tuberculosis, bacterial pneu monia, and malignancy. Transudative effusion is due to systemic diseases like cardiac failure, cirr hosis of liver. Conventional methods of diagnosis may not be able to establish the cause of pleural e ffusion. Early diagnosis and management reduces the morbidity and mortality. AIM: The objective of the study is to estimate pleural fluid Adenosine Deaminase (ADA and C - reactive protein (CRP leve ls and to evaluate their efficacy in differential diagnosis of transudative and exudative, tuberculou s and non tuberculous and inflammatory and non inflammatory effusions. MATERIAL AND METHODS: Fifty two patients of pleural effusion were investigated and divided into four groups base d on diagnosis. Group I, II, III and IV had 24 cases of tuberculous effusion, 13 cases of transuda tive effusion, 08 cases of malignant effusion and 07 cases of parapneumonic effusion respectively. Pl eural fluid was analyzed for ADA (Guisti and Galanti’s method and CRP (turbidometric immunoassa y. STATISTICAL ANALYSIS: The statistical analysis was done using unpaired student‘t’ test an d p value < 0.05 was considered statistically significant. RESULTS: In the present study pleural fluid ADA revealed hig hly significant increase in tuberculous effusion than non tuberculous effusions (p <0.001 and also when compared with non tuberculous subgroups, transudative effusion (p < 0 .001, malignant effusion (p<0.001, and PPE (p<0.01. ADA levels at a cutoff value of 40U/L, sh owed sensitivity, specificity, positive predictive value and negative predictive value of 91.67%, 89.3 %, 88% & 92.6% respectively in tuberculous effusion. Pleural fluid CRP levels in parapneumonic effusion were significantly higher compared to other types of effusions (p<0.001. Significantly h igher levels of CRP were seen in exudative effusion compared to

  1. Contrasting responses of root morphology and root-exuded organic acids to low phosphorus availability in three important food crops with divergent root traits

    Wang, Yan-Liang; Almvik, Marit; Clarke, Nicholas; Eich-Greatorex, Susanne; Øgaard, Anne Falk; Krogstad, Tore; Lambers, Hans; Clarke, Jihong Liu

    2015-01-01

    Phosphorus (P) is an important element for crop productivity and is widely applied in fertilizers. Most P fertilizers applied to land are sorbed onto soil particles, so research on improving plant uptake of less easily available P is important. In the current study, we investigated the responses in root morphology and root-exuded organic acids (OAs) to low available P (1 μM P) and sufficient P (50 μM P) in barley, canola and micropropagated seedlings of potato—three important food crops with divergent root traits, using a hydroponic plant growth system. We hypothesized that the dicots canola and tuber-producing potato and the monocot barley would respond differently under various P availabilities. WinRHIZO and liquid chromatography triple quadrupole mass spectrometry results suggested that under low P availability, canola developed longer roots and exhibited the fastest root exudation rate for citric acid. Barley showed a reduction in root length and root surface area and an increase in root-exuded malic acid under low-P conditions. Potato exuded relatively small amounts of OAs under low P, while there was a marked increase in root tips. Based on the results, we conclude that different crops show divergent morphological and physiological responses to low P availability, having evolved specific traits of root morphology and root exudation that enhance their P-uptake capacity under low-P conditions. These results could underpin future efforts to improve P uptake of the three crops that are of importance for future sustainable crop production. PMID:26286222

  2. Contrasting responses of root morphology and root-exuded organic acids to low phosphorus availability in three important food crops with divergent root traits.

    Wang, Yan-Liang; Almvik, Marit; Clarke, Nicholas; Eich-Greatorex, Susanne; Øgaard, Anne Falk; Krogstad, Tore; Lambers, Hans; Clarke, Jihong Liu

    2015-01-01

    Phosphorus (P) is an important element for crop productivity and is widely applied in fertilizers. Most P fertilizers applied to land are sorbed onto soil particles, so research on improving plant uptake of less easily available P is important. In the current study, we investigated the responses in root morphology and root-exuded organic acids (OAs) to low available P (1 μM P) and sufficient P (50 μM P) in barley, canola and micropropagated seedlings of potato-three important food crops with divergent root traits, using a hydroponic plant growth system. We hypothesized that the dicots canola and tuber-producing potato and the monocot barley would respond differently under various P availabilities. WinRHIZO and liquid chromatography triple quadrupole mass spectrometry results suggested that under low P availability, canola developed longer roots and exhibited the fastest root exudation rate for citric acid. Barley showed a reduction in root length and root surface area and an increase in root-exuded malic acid under low-P conditions. Potato exuded relatively small amounts of OAs under low P, while there was a marked increase in root tips. Based on the results, we conclude that different crops show divergent morphological and physiological responses to low P availability, having evolved specific traits of root morphology and root exudation that enhance their P-uptake capacity under low-P conditions. These results could underpin future efforts to improve P uptake of the three crops that are of importance for future sustainable crop production. PMID:26286222

  3. A stable-isotope mass spectrometry-based metabolic footprinting approach to analyze exudates from phytoplankton

    Weber, Ralf J. M.; Selander, Erik; Sommer, Ulf;

    2013-01-01

    Phytoplankton exudates play an important role in pelagic ecology and biogeochemical cycles of elements. Exuded compounds fuel the microbial food web and often encompass bioactive secondary metabolites like sex pheromones, allelochemicals, antibiotics, or feeding attractants that mediate biologica...

  4. Disappearance of diabetic macular hard exudates after hemodialysis introduction.

    Matsuo,Toshihiko

    2006-06-01

    Full Text Available

    We report herein the disappearance of macular hard exudates after the introduction of hemodialysis in diabetic patients. A 62-year-old woman and a 52-year-old man with diabetes mellitus showed hard exudates in the macula of the left eyes. Both patients had previously undergone panretinal photocoagulation in both eyes. During the follow-up, hemodialysis was introduced for deteriorating chronic renal failure caused by diabetic nephropathy. Half a year later, macular hard exudates in the left eyes disappeared dramatically in both patients, but the visual acuity remained the same. No additional laser treatment was done during the observation period. Hemodialysis is considered to have accelerated the resolution of macular hard exudates in both patients. The deposition of macular hard exudates in diabetic patients is due in part to concurrent poor renal function.

  5. Root-exuded acid phosphatase and 32Pi-uptake kinetics of wheat, rye and triticale under phosphorus starvation

    A nutrient culture experiment was conducted with cereal species viz., wheat (Triticum aestivum L.) cv. PBW-343), rye (Secale cereale L cv. R-308) and triticale (Triticale octoploide L. cv. DT-46), a hybrid of wheat and rye, to examine the genetic variation in root-exuded acid phosphatase (ACPase) activity and kinetics of 32Pi-uptake under P deficient condition. The ACPase activity was assayed in the extract (intra-) and on surface (extra-cellular) or root, using p-nitrophenyl phosphate as substrate. Significantly higher ACPase activity was observed in wheat followed by rye and triticale both on the root surface and in root extract. In general, root surface ACPase activity was 2.2-fold higher than that in root extract. A strong correlation (r2 = 0.87**) between extra and intra-cellular ACPase activity was observed. In terms of kinetic parameters, it was observed that 32Pi uptake and Imax values were significantly higher in rye while Cmin and Km were lowest compared to wheat and triticale. The dry weights of shoot, root and total plant were significantly higher in rye compared to wheat and triticale. Rye also had higher amount of total plant P content The superiority of rye over wheat and triticale in P uptake was observed mainly due to efficient Pi-uptake system, which needs further studies to ascertain the enhancement of Pi-induced high-affinity P transporter in these cereals. (author)

  6. The Content of Phenolic Compounds in the Pea Seedling Root Exudates Depends on the Size of Their Roots and Inoculation of Bacteria Mutualistic and Antagonistic Type of Interactions

    L.E. Makarova; L.V. Dudareva; I.G. Petrova

    2015-01-01

    The effect of the bacteria Rhizobium and Pseudomonas on total content of phenolic compounds (PC) and their individual components (apigenin, naringenin, dibutyl-ortho-phthalate, pisatin, N-phenyl-2-naphthylamine) in the root exudates of the pea seedlings (Pisum sativum L. ) at two different growth stages was studied . Bacteria have similar affect on the total number of PC and the number of constituent apigenine, phthalate and pisatine. Difference at the impact of these bacteria on the content ...

  7. Allelopathic effect of black mustard tissues and root exudates on some crops and weeds Efeito alelopático de tecidos de mostarda-preta e exsudatos da raiz de algumas culturas e plantas daninhas

    E Al-Sherif; A.K. Hegazy; N.H. Gomaa; Hassan, M O

    2013-01-01

    Laboratory and greenhouse experiments were conducted to evaluate the phytotoxic effect of black mustard extracts and root exudates on two crops: Trifolium alexandrinum and Triticum aestivum, and two weeds: Phalaris paradoxa and Sisymbrium irio. The seeds were treated with aqueous and ethanolic extracts and chloroform for eight days, or subjected to root exudates of just harvested mustard in a greenhouse for five weeks. High-performance liquid chromatography (HPLC) was used to quantify phytoto...

  8. Aluminum tolerance of two wheat cultivars (Brevor and Atlas66) in relation to their rhizosphere pH and organic acids exuded from roots.

    Wang, Ping; Bi, Shuping; Ma, Liping; Han, Weiying

    2006-12-27

    Phytotoxicity of aluminum (Al) has become a serious problem in inhibiting plant growth on acid soils. Under Al stress, the changes of rhizosphere pH, root elongation, absorption of Al by wheat roots, organic acids exuded from roots, and some main factors related to Al-tolerant mechanisms have been studied using hydroponics, fluorescence spectrophotometry, and high performance liquid chromatography (HPLC). Two wheat cultivars, Brevor and Atlas66, differing in Al tolerance are chosen in the study. Accordingly, the rhizosphere pH has a positive effect on Al tolerance. Atlas66 (Al-tolerant) has higher capability to maintain high rhizosphere pH than Brevor (Al-sensitive) does. High pH can reduce Al3+ activity and toxicity, and increase the efficiency of exuding organic acids from the roots. More inhibition of root elongation has been found in Brevor because of the exposure of roots to Al3+ solution at low pH. Brevor accumulate more Al in roots than Atlas66 even at higher pH. Al-induced exudation of malic and citric acids has been found in Atlas66 roots, while no Al-induced organic acids have been found in Brevor. These results indicate that the Al-induced secretion of organic acids from Atlas66 roots has a positive correlation with Al tolerance. Comprehensive treatment of Al3+ and H+ indicates that wheat is adversely influenced by excess Al3+, rather than low pH. PMID:17177538

  9. Salivary gland structure of Ctenarytaina eucalypti (MASKELL, 1890 (Hemiptera and phloem exudate in Eucalyptus globulus LABILLARDIÈRE, 1799 (Myrtaceae

    Sharma Anamika

    2015-03-01

    Full Text Available The structure of the salivary glands of the free-living aphalarid Ctenarytaina eucalypti, which infests multiple species of Eucalyptus in Australasia and has been introduced into many other regions of the world, is described and illustrated. The principal salivary gland is multilobed whereas the accessory gland is tubular. 1-D electrophoresis revealed proteins of approximately 58 and 64 kDa in the salivary gland extracts and proteins of similar molecular weights in the extracted plant exudates, including phloem, from infested leaves and tender shoots of E. globulus. Proteins that could fall within this range include, but are not limited to, glucosemethanol- choline-oxidoreductase (53-66 kDa, Zn-binding dehydrogenase (67 kDa and esterase (65-96 kDa, in addition to cytochrome P-450 (50-55 kDa, trehalase (56 kDa, amylase (50-75 kDa and lipase (48-52 kDa. Previous studies indicate that glucose-methanol-cholineoxidoreductase, Zn-binding dehydrogenase, cytochrome P-450 and trehalase suppress plantdefence mechanisms, whereas the cell-degrading enzymes such as amylase, lipase and esterase have a possible role in enabling C. eucalypti to insert its stylet into leaf and shoot tissues of E. globulus.

  10. Bioavailable concentrations of germanium and rare earth elements in soil as affected by low molecular weight organic acids and root exudates

    Wiche, Oliver; Székely, Balázs; Kummer, Nicolai-Alexeji; Heinemann, Ute; Tesch, Silke; Heilmeier, Hermann

    2014-05-01

    Availability of elements in soil to plant is generally dependent on the solubility and mobility of elements in soil solution which is controlled by soil, elemental properties and plant-soil interactions. Low molecular organic acids or other root exudates may increase mobility and availability of certain elements for plants as an effect of lowering pH in the rhizosphere and complexation. However, these processes take place in a larger volume in soil, therefore to understand their nature, it is also important to know in which layers of the soil what factors modify these processes. In this work the influence of citric acid and root exudates of white lupin (Lupinus albus L.) on bioavailable concentrations of germanium, lanthan, neodymium, gadolinium and erbium in soil solution and uptake in root and shoot of rape (Brassica napus L.), comfrey (Symphytum officinale L.), common millet (Panicum milliaceum L.) and oat (Avena sativa L.) was investigated. Two different pot experiments were conducted: (1) the mentioned plant species were treated with nutrient solutions containing various amount of citric acid; (2) white lupin was cultivated in mixed culture (0 % lupin, 33 % lupin) with oat (Avena sativa L.) and soil solution was obtained by plastic suction cups placed at various depths. As a result, addition of citric acid significantly increased germanium concentrations in plant tissue of comfrey and rape and increased translocation of germanium, lanthan, neodymium, gadolinium and erbium from root to shoot. The cultivation of white lupin in mixed culture with oat led to significantly higher concentrations of germanium and increasing concentrations of lanthan, neodymium, gadolinium and erbium in soil solution and aboveground plant tissue. In these pots concentrations of citric acid in soil solution were significantly higher than in the control. The results show, that low molecular organic acids exuded by plant roots are of great importance for the mobilization of germanium

  11. Intravitreal Aflibercept Outcomes in Patients with Persistent Macular Exudate Previously Treated with Bevacizumab and/or Ranibizumab for Neovascular Age-Related Macular Degeneration

    David R. Griffin; Richmond, Preston P; John C. Olson

    2014-01-01

    Purpose. To assess whether intravitreal aflibercept (2.0 mg) can effectively reduce persistent macular exudate and enhance visual acuity in ranibizumab (0.5 mg) and/or bevacizumab (1.25 mg) treatment resistant patients with neovascular age-related macular degeneration. Methods. This retrospective study included 47 treatment resistant eyes from 47 patients switched to intravitreal aflibercept injections after receiving a minimum of 3 injections with either ranibizumab or bevacizumab. Snellen v...

  12. Carbon content and C:N ratio of transparent exopolymeric particles (TEP) produced by bubbling exudates of diatoms

    Mari, Xavier

    1999-01-01

    The carbon content of transparent exopolymeric particles (TEP) was measured in the laboratory in particles produced by bubbling exudates of the diatom Thalassiosira weissflogii, grown under nitrogen non-limited conditions (N:P = 7). The carbon content of these particles (TEP-C) appears to vary as a...... function of their size according to TEP-C = 0.25 x 10-6 r2.55 (µg C TEP-1), where r is the equivalent spherical radius of the TEP particle (µm). This relationship implies that TEP are fractal aggregates having a fractal dimension D = 2.55. When this value was applied to historical TEP size spectra from a...... coastal area (Kattegat, Denmark), TEP carbon concentration in the surface mixed layer was on the order of 230 ± 150 µg C l-1. This is high relative to other sources of particulate organic carbon (e.g. phytoplankton) and depending on TEP turnover rates, suggests that TEP is an important pathway for...

  13. Staphylococcus hyicus virulence in relation to exudative epidermitis in pigs

    Wegener, Henrik Caspar; Andresen, Lars Ole; Bille-Hansen, Vivi

    1993-01-01

    Staphylococcus hyicus strains with different phage types, plasmid profiles, and antibiotic resistance patterns were isolated from piglets with exudative epidermitis. The strains could be divided into virulent strains, producing exudative epidermitis, and avirulent strains, producing no dermal...... concluded that crusting reaction of piglet skin is a suitable indicator of virulence in S. hyicus in relation to exudative epidermitis, and that virulent strains produce a 30 kDa protein, absent in concentrated culture supernatants from avirulent strains. This 30 kDa protein might be an exfoliative toxin....

  14. 广藿香根系分泌物的化感自毒作用研究%Study on the Allelopathy and the Autotoxicity of Patchouli Root Exudates

    李玲梅; 李明

    2011-01-01

    以组培苗为材料,应用组织培养技术分析广藿香根系分泌物对萝卜、广金钱草和广藿香组培苗生长的影响.结果表明,广藿香根系分泌物抑制广藿香组培苗和广金钱草的生长;低浓度能促进萝卜生长,高浓度抑制其生长.根系分泌物对广藿香的不利影响随浓度的增加而增大,表明根系分泌物可能是导致广藿香连作障碍的主要原因之一.%The effect of root exudates on the growth of radish, Desmodium styracifoliurn and patchouli tissue culture were analyzed using tissue culture method. Results showed that root exudates of patchouli inhibited the growth of the patchouli tissue culture and Desmodium styracifoliurn;The low concentration of root exudates promoted the growth of the radish, the high concentration of root exudates inhibited the growth of the radish. The greater concentration of root exudates in the medium,the more adverse effect it had on the plants.It is concluded that root exudates of patchouli was one of the important factors inducing continuous cropping obstacle in patchouli.

  15. Novel mutations in FZD4 and phenotype–genotype correlation in Chinese patients with familial exudative vitreoretinopathy

    Tang, Miao; Ding, Xiaoyan; Li, Jiaqing; Hu, Andina; Yuan, Miner; Yang, Yu; Zhan, Zongyi; Li, Zijing

    2016-01-01

    Purpose To identify novel mutations in the frizzled 4 (FZD4) gene in patients with familial exudative vitreoretinopathy (FEVR) in southern China and to delineate the mutation-associated clinical manifestations. Methods Clinical data and genomic DNA were collected from 100 probands and their family members. The coding regions of FZD4 were screened for mutations with PCR and Sanger sequencing. Cosegregation analysis was used to verify suspected variants, and clinical symptoms in the probands were analyzed. Results Fourteen causative heterozygous mutations in FZD4 in 21 unrelated probands were noted, in 21.0% of the index patients (21/100). Four novel missense mutations (C45R, C45S, C53S, and C90R) and three novel deletion mutations (T326fsX356, G492fsX512, and S345_A351del) with a high possibility of pathogenicity were detected. None of these mutations were found in current online databases and 150 ethnically matched control subjects without retinopathy. The majority of the mutations in FZD4 were identified in probands with retinal folds (15/21) and ectopic macula (5/21). No mutations in FZD4 were found in probands with complete tractional retinal detachment in infancy or with mild asymptomatic FEVR in adulthood. Conclusions Seven novel mutations found in this study have broadened the spectrum of mutations in FZD4 known to cause FEVR, providing a deeper understanding of this disease. The results show that mutations in FZD4 are associated with the phenotypes of retinal folds or ectopic macula in FEVR but might not be associated with extreme severe bilateral FEVR during infancy, at least in southern Chinese patients. PMID:27555740

  16. Automatic Detection of Retinal Exudates using a Support Vector Machine

    Nualsawat HIRANSAKOLWONG

    2013-02-01

    Full Text Available Retinal exudates are among the preliminary signs of diabetic retinopathy, a major cause of vision loss in diabetic patients. Correct and efficient screening of exudates is very expensive in professional time and may cause human error. Nowadays, the digital retinal image is frequently used to follow-up and diagnoses eye diseases. Therefore, the retinal image is crucial and essential for experts to detect exudates. Unfortunately, it is a normal situation that retinal images in Thailand are poor quality images. In this paper, we present a series of experiments on feature selection and exudates classification using the support vector machine classifiers. The retinal images are segmented following key preprocessing steps, i.e., color normalization, contrast enhancement, noise removal and color space selection. On data sets of poor quality images, sensitivity, specificity and accuracy is 94.46%, 89.52% and 92.14%, respectively.

  17. Structure and dynamics of microbe-exuded polymers and their interactions with calcite surfaces.

    Cygan, Randall Timothy; Mitchell, Ralph (Harvard University, Cambridge, MA); Perry, Thomas D. (Harvard University, Cambridge, MA)

    2005-12-01

    Cation binding by polysaccharides is observed in many environments and is important for predictive environmental modeling, and numerous industrial and food technology applications. The complexities of these organo-cation interactions are well suited to predictive molecular modeling studies for investigating the roles of conformation and configuration of polysaccharides on cation binding. In this study, alginic acid was chosen as a model polymer and representative disaccharide and polysaccharide subunits were modeled. The ability of disaccharide subunits to bind calcium and to associate with the surface of calcite was investigated. The findings were extended to modeling polymer interactions with calcium ions.

  18. Comparative nasal effects of bradykinin and histamine: influence on nasal airways resistance and plasma protein exudation.

    Rajakulasingam, K.; Polosa, R; Lau, L.C.; Church, M. K.; Holgate, S T; Howarth, P. H.

    1993-01-01

    BACKGROUND--Bradykinin may contribute to the pathogenesis of allergic rhinitis. Like histamine, nasal challenge with bradykinin induces rhinorrhoea, nasal blockage, and plasma protein leakage. Their comparative nasal potencies have not, however, been fully elucidated. METHODS--Three double blind, randomised, placebo controlled and cross-over studies were undertaken to compare objectively the nasal effects of bradykinin, histamine, and vehicle. RESULTS--Both bradykinin and histamine produced d...

  19. Clinical case of exudative pleuritis in stallion

    A casual exudative pleuritis in 2 years old stallion, Holsteiner breed, has been outlined. The disease is extremely rare in this country. Comprehensive examinations have been made during the period of hospitalization: daily clinical examinations, double renthgenography; regular haematological and biochemical tests; microbiological culture tests with an antibioticogram; laboratory tests of punctate and periodical ultrasound tests. The examinations and tests have been carried out at the Internal Noncontagious Disease Clinic at the Veterinary Faculty of the Thracian University in Stara Zagora

  20. The Content of Phenolic Compounds in the Pea Seedling Root Exudates Depends on the Size of Their Roots and Inoculation of Bacteria Mutualistic and Antagonistic Type of Interactions

    L.E. Makarova

    2015-09-01

    Full Text Available The effect of the bacteria Rhizobium and Pseudomonas on total content of phenolic compounds (PC and their individual components (apigenin, naringenin, dibutyl-ortho-phthalate, pisatin, N-phenyl-2-naphthylamine in the root exudates of the pea seedlings (Pisum sativum L. at two different growth stages was studied . Bacteria have similar affect on the total number of PC and the number of constituent apigenine, phthalate and pisatine. Difference at the impact of these bacteria on the content of naringenin and N-phenyl-2-naphthylamine was detected, which can be attributed to the peculiarities of the interactions of plants of peas with bacteria-antagonists and mutualists.

  1. Elimination of browning exudate and in vitro development of shoots in Pistacia vera L. cv. mateur and Pistacia atlantica Desf. Culture

    M. I. Trujillo; S. Mederos-Molina

    2014-01-01

    We report diminution and/or elimination of browning exudate followed by in vitro establishment of in Pistacia vera cv. mateur and Pistacia atlantica explants. Soaking P. vera cv. mateur explants prior to culture in L-cysteine HCl for 15 min (100 µM) inhibits blackening of the modified Murashige and Skoog medium - MS + 400 mg/l NH4NO3 - and of the explants; while shoot formation was increased. The browning in P. vera cv. mateur and P. atlantica explants dissolved when modified MS and Quoirin a...

  2. Effects of Tomato Root Exudates on Meloidogyne incognita.

    Yang, Guodong; Zhou, Baoli; Zhang, Xinyu; Zhang, Zijun; Wu, Yuanyuan; Zhang, Yiming; Lü, Shuwen; Zou, Qingdao; Gao, Yuan; Teng, Long

    2016-01-01

    Plant root exudates affect root-knot nematodes egg hatch. Chemicals in root exudates can attract nematodes to the roots or result in repellence, motility inhibition or even death. However, until recently little was known about the relationship between tomato root exudates chemicals and root-knot nematodes. In this study, root exudates were extracted from three tomato rootstocks with varying levels of nematode resistance: Baliya (highly resistant, HR), RS2 (moderately resistant, MR) and L-402 (highly susceptible, T). The effects of the root exudates on Meloidogyne incognita (M. incognita) egg hatch, survival and chemotaxis of second-stage juveniles (J2) were explored. The composition of the root exudates was analysed by gas chromatography/mass spectrometry (GC/MS) prior to and following M. incognita inoculation. Four compounds in root exudates were selected for further analysis and their allopathic effect on M. incognita were investigated. Root exudates from each tomato rootstocks (HR, MR and T strains) suppressed M. incognita egg hatch and increased J2 mortality, with the highest rate being observed in the exudates from the HR plants. Exudate from HR variety also repelled M. incognita J2 while that of the susceptible plant, T, was demonstrated to be attractive. The relative amount of esters and phenol compounds in root exudates from HR and MR tomato rootstocks increased notably after inoculation. Four compounds, 2,6-Di-tert-butyl-p-cresol, L-ascorbyl 2,6-dipalmitate, dibutyl phthalate and dimethyl phthalate increased significantly after inoculation. The egg hatch of M. incognita was suppressed by each of the compound. L-ascorbyl 2,6-dipalmitate showed the most notable effect in a concentration-dependent manner. All four compounds were associated with increased J2 mortality. The greatest effect was observed with dimethyl phthalate at 2 mmol·L-1. Dibutyl phthalate was the only compound observed to repel M. incognita J2 with no effect being detected in the other

  3. Effects of Tomato Root Exudates on Meloidogyne incognita.

    Guodong Yang

    Full Text Available Plant root exudates affect root-knot nematodes egg hatch. Chemicals in root exudates can attract nematodes to the roots or result in repellence, motility inhibition or even death. However, until recently little was known about the relationship between tomato root exudates chemicals and root-knot nematodes. In this study, root exudates were extracted from three tomato rootstocks with varying levels of nematode resistance: Baliya (highly resistant, HR, RS2 (moderately resistant, MR and L-402 (highly susceptible, T. The effects of the root exudates on Meloidogyne incognita (M. incognita egg hatch, survival and chemotaxis of second-stage juveniles (J2 were explored. The composition of the root exudates was analysed by gas chromatography/mass spectrometry (GC/MS prior to and following M. incognita inoculation. Four compounds in root exudates were selected for further analysis and their allopathic effect on M. incognita were investigated. Root exudates from each tomato rootstocks (HR, MR and T strains suppressed M. incognita egg hatch and increased J2 mortality, with the highest rate being observed in the exudates from the HR plants. Exudate from HR variety also repelled M. incognita J2 while that of the susceptible plant, T, was demonstrated to be attractive. The relative amount of esters and phenol compounds in root exudates from HR and MR tomato rootstocks increased notably after inoculation. Four compounds, 2,6-Di-tert-butyl-p-cresol, L-ascorbyl 2,6-dipalmitate, dibutyl phthalate and dimethyl phthalate increased significantly after inoculation. The egg hatch of M. incognita was suppressed by each of the compound. L-ascorbyl 2,6-dipalmitate showed the most notable effect in a concentration-dependent manner. All four compounds were associated with increased J2 mortality. The greatest effect was observed with dimethyl phthalate at 2 mmol·L-1. Dibutyl phthalate was the only compound observed to repel M. incognita J2 with no effect being detected in

  4. Study of the Chemical Composition of the Resinous Exudate Isolated from Heliotropium Sclerocarpum and Evaluation of the Antioxidant Properties of the Phenolic Compounds and the Resin

    René Torres

    2009-11-01

    Full Text Available Heliotropium sclerocarpum Phil. (Heliotropiaceae is a resinous bush that grows in the Atacama of northern Chile. The chemical composition of its resinous exudate was analyzed for the first time. One aromatic geranyl derivative: filifolinol (1, one flavanone: naringenin (2 and a new type of 3-oxo-2-arylbenzofuran derivative 3 were isolated and their structures were determined. The antioxidant activity of the phenolic compounds and resin was evaluated using the bleaching of DPPH radical method and expressed as fast reacting equivalents (FRE and total reacting equivalents (TRE.

  5. Ability of Agrogyron elongatum to accumulate the single metal of cadmium, copper, nickel and lead and root exudation of organic acids

    2001-01-01

    Agrogyron elongatum were grown in nutrient solution containing moderate to high amounts of separate heavy metal of Cd, Cu, Ni and Pb in a greenhouse for a 9-day. Cd, Cu, Ni and Pb generally led to decrease in the elongation of roots although the length of seedlings exposed to Cd and Pb at 0,05 and 0.5 mg/L showed to be slightly greater than that of controls. Of the four metals in the experiment, Pb was absorbed and accumulated to the highest level, with the concentrations of 92754 mg/kg dry weight (DW) in roots and 11683 mg/kg DW in shoots. Cd was moderately accumulated in Agrogyron elongatum, but the maximum bioaccumulation coefficients (BCs) for rpots and shoots were observed. The patterns for Cu and Ni uptake and distribution in plants differed from those of Pb and Cd, as it was showed that the shoot accumulation of Cu and Ni was significantly higher than in roots. A. elongatum had the highest Ni concentration in shoots (30261 mg/kg DW)at the external concentration of 250 mg/L. Cu ranked second, with a shoot concentration of 12230 mg/kg DW when 50 mg/L Cu in solution was applied. For the four trace elements tested, the highest concentrations in shoots decreased by the order of Ni > Cu > Pb > Cd (mg/kg DW),and those in roots were Pb > Cd > Ni > Cu (mg/kg DW). Malic, oxalic and citric acids exuded by roots exposed to 1 and 50 mg/L of the metals were detected. Release of organic acids from plants significantly differed among the metal treatments. Cu was most effectively in inducing rpot exudation of the three types of organic acids. Cd, and Ni were also the inducers of secretion of malic and oxalic acids. With reference of Pb,a small amounts of malic and oxalic acids were detected in the root exudates, but few quantities of citric acid were found. However, no orrelation between alternations in root exudation of organic acids and metal accumulation could be established.

  6. Mineral protection of soil carbon counteracted by root exudates

    Keiluweit, Marco; Bougoure, Jeremy J.; Nico, Peter S.; Pett-Ridge, Jennifer; Weber, Peter K.; Kleber, Markus

    2015-06-01

    Multiple lines of existing evidence suggest that climate change enhances root exudation of organic compounds into soils. Recent experimental studies show that increased exudate inputs may cause a net loss of soil carbon. This stimulation of microbial carbon mineralization (`priming’) is commonly rationalized by the assumption that exudates provide a readily bioavailable supply of energy for the decomposition of native soil carbon (co-metabolism). Here we show that an alternate mechanism can cause carbon loss of equal or greater magnitude. We find that a common root exudate, oxalic acid, promotes carbon loss by liberating organic compounds from protective associations with minerals. By enhancing microbial access to previously mineral-protected compounds, this indirect mechanism accelerated carbon loss more than simply increasing the supply of energetically more favourable substrates. Our results provide insights into the coupled biotic-abiotic mechanisms underlying the `priming’ phenomenon and challenge the assumption that mineral-associated carbon is protected from microbial cycling over millennial timescales.

  7. Root exudation of phytosiderophores from soil-grown wheat

    Oburger, Eva; Gruber, Barbara; Schindlegger, Yvonne; Schenkeveld, Walter D C; Hann, Stephan; Kraemer, Stephan M; Wenzel, Walter W.; Puschenreiter, Markus

    2014-01-01

    For the first time, phytosiderophore (PS) release of wheat (Triticum aestivum cv Tamaro) grown on a calcareous soil was repeatedly and nondestructively sampled using rhizoboxes combined with a recently developed root exudate collecting tool. As in nutrient solution culture, we observed a distinct diurnal release rhythm; however, the measured PS efflux was c. 50 times lower than PS exudation from the same cultivar grown in zero iron (Fe)-hydroponic culture. Phytosiderophore rhizosphere soil so...

  8. Unilateral, recurrent exudative retinal detachment in association with pansinusitis [

    Osman Saatci, Ali

    2012-11-01

    Full Text Available [english] Aim: To report a patient with unilateral exudative retinal detachment due to pansinusitis.Methods: Case report.Results: A 65-year-old woman with a two-month history of blurred vision, red eye and lid swelling in her left eye was referred to us. Her best-corrected visual acuity was 20/20 in the right eye and 20/200 in the left. Conjunctival vessels were engorged in the OS. Funduscopy revealed a 360° exudative detachment in OS and computerized tomography (CT imaging revealed pansinusitis. Systemic antibiotic treatment was employed and exudative detachment regressed. However, exudative detachment remitted as soon as antibiotic treatment ceased. Finally she underwent sinus surgery and decompression of the orbita. Her visual acuity improved to 20/100 just two days after the surgery, stabilized at 20/30 and no further recurrences occured during the follow-up of 10 months.Conclusion: Since exudative retinal detachment usually accompanies systemic inflammatory or neoplastic diseases, systemic screening and collaboration with other disciplines are mandatory. To the best of our knowledge, this is the first report of a case that developed exudative retinal detachment due to pansinusitis and only recovered after decompression surgery.

  9. Genetic variants in three genes and smoking show strong associations with susceptibility to exudative age-related macular degeneration in a Chinese population

    2008-01-01

    Background The present study was undertaken to replicate the associations of representative polymorphisms in three genes (complement factor H (CFH), complement factor B (BF) and HtrA serine peptidase 1 (HTRA1)) with exudative age-related macular degeneration (AMD) in a Hart Chinese population, and to test if the modifiable environmental factors affect AMD susceptibility associated with different type of genotype in these genes. Methods An age, gender and ethnicity matched case-control study was conducted to genotype the representative single neucleotide polymorphisms (SNPs) loci including rs1061170 and rs1410996 in CFH, rs641153 and rs4151667 in BF and rs11200638 in HTRA1 gene in 144 exudative AMD patients and 126 normal controls using PCR-RFLP and directresequencing. The demographic characteristics and behavioral risk factors were also recorded. Allelic and genotypic associations for individual SNP and joint associations with two loci were performed. The gene-gene and gene-environment interactions were analyzed using multivariate non-conditional Logistic regression analysis. Results The C risk allele frequencies for CFH Y402H (rs1061170) in cases and controls were 12.5% and 5.4% respectively, which were much lower than those in Caucasians (P<0.001). Compared with TT homozygous genotype, the CT heterozygous genotype was positively associated with AMD with odds ratio (OR) of 3.23 (1.36-5.07). However, the population attributable risk (PAR) of C allele was only 3.3% (1.4%-4.3%). rs1410996 was also associated with AMD independent of Y402H. The ORs of exudative AMD for individuals carrying one copy risk allele and two copy risk alleles were 2.57 (1.21-5.45) and 4.76 (2.15-10.55) respectively, with correspondent PARs of 28.3% (2.0%-40.5%) and 38.2% (21.8%-45.4%). rs11200638 in HTRA1 was another susceptible locus for AMD and the risk homozygotes were significantly susceptible for exudutive AMD (OR=3.98, 1.88-8.43) with PAR of 38.9% (24.3%-45.8%). Education status and

  10. PHYTOREMEDIATION: PLANT UPTAKE OF ATRAZINE AND THE ROLE OF ROOT EXUDATES. (R825549C060)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  11. 14CO2 labeling. A reliable technique for rapid measurement of total root exudation capacity and vascular sap flow in crop plants

    Root release of organic compounds and rate of the vascular sap flow are important for understanding the nutrient and the source-sink dynamics in plants, however, their determination is procedurally cumbersome and time consuming. We report here a simple method involving 14C labeling for rapid and reliable measurement of root exudates and vascular sap flow rate in a variable groundnut population developed through seed gamma irradiation using a cobalt source (60Co). An experimental hypothesis that a higher 14C level in the vascular sap would indicate a higher root release of carbon by the roots into the rhizosphere was verified. (author)

  12. Prostaglandin E1 and prostaglandin F2 alpha in exudate in nickel allergy

    Lerche, A; Bisgaard, H; Kassis, V; Christensen, J D; Søndergaard, J

    1989-01-01

    Ten nickel-allergic patients and 5 healthy control subjects participated in a study of the kinetics of the flux and concentration of migrated leukocytes and extracellular PGE1 and PGF2 alpha during a 48 h period, using a skin chamber technique. The patients were provided with two skin chambers, o...

  13. Modeling of Nonlinear Dynamics and Synchronized Oscillations of Microbial Populations, Carbon and Oxygen Concentrations, Induced by Root Exudation in the Rhizosphere

    Molz, F. J.; Faybishenko, B.; Jenkins, E. W.

    2012-12-01

    Mass and energy fluxes within the soil-plant-atmosphere continuum are highly coupled and inherently nonlinear. The main focus of this presentation is to demonstrate the results of numerical modeling of a system of 4 coupled, nonlinear ordinary differential equations (ODEs), which are used to describe the long-term, rhizosphere processes of soil microbial dynamics, including the competition between nitrogen-fixing bacteria and those unable to fix nitrogen, along with substrate concentration (nutrient supply) and oxygen concentration. Modeling results demonstrate the synchronized patterns of temporal oscillations of competing microbial populations, which are affected by carbon and oxygen concentrations. The temporal dynamics and amplitude of the root exudation process serve as a driving force for microbial and geochemical phenomena, and lead to the development of the Gompetzian dynamics, synchronized oscillations, and phase-space attractors of microbial populations and carbon and oxygen concentrations. The nonlinear dynamic analysis of time series concentrations from the solution of the ODEs was used to identify several types of phase-space attractors, which appear to be dependent on the parameters of the exudation function and Monod kinetic parameters. This phase space analysis was conducted by means of assessing the global and local embedding dimensions, correlation time, capacity and correlation dimensions, and Lyapunov exponents of the calculated model variables defining the phase space. Such results can be used for planning experimental and theoretical studies of biogeochemical processes in the fields of plant nutrition, phyto- and bio-remediation, and other ecological areas.

  14. Plant root-driven hydraulic redistribution, root nutrient uptake and carbon exudation interact with soil properties to generate rhizosphere resource hotspots that vary in space and time

    Espeleta, J. F.; Neumann, R. B.; Cardon, Z. G.; Mayer, K. U.; Rastetter, E. B.

    2014-12-01

    Hydraulic redistribution (HR) of soil water by plants occurs in seasonally dry ecosystems worldwide. During drought, water flows from deep moist soil, through plant roots, into dry (often litter-rich) upper soil layers. Using modeling, we explored how physical transport processes driven by transpiration and hydraulic redistribution interact with root physiology (nutrient uptake and carbon exudation) and soil properties (soil texture and cation exchange) to influence nitrogen and carbon concentrations in the rhizosphere. At the single root scale, we modeled a 10-cm radial soil domain, and simulated solute transport, soil cation exchange, and root exudation and nutrient uptake under two water flow patterns: daytime transpiration without nighttime HR, and daytime transpiration with nighttime HR. During HR, water efflux flushed solutes away from the root, diluting the concentrations of key nutrients like nitrate. The transport of cations by transpiration in the day and their accumulation near the root led to competitive desorption of ammonium from soil further from the root and generation of hotspots of ammonium availability at night. HR influenced the spatial and temporal patterns of these hotspots and their intensity. They were also influenced by soil properties of texture and cation exchange capacity. This dynamic resource landscape caused by diel cycling between transpiration and hydraulic redistribution presents a stage for greater complexity of microbial interactions. We are currently embedding a microbial community and small food web into this rhizosphere model in order to explore how organisms responsible for nutrient and soil carbon cycling respond to these fluctuating resource regimes.

  15. Flaminal enzyme alginogel: a novel approach to the control of wound exudate, bioburden and debridement.

    White, Richard J

    2014-05-01

    A multidisciplinary panel of Woundcare experts of international repute was assembled to review the clinical evidence and advise on the classification of the Flaminal products. This is based on their exact role in wound management and is to be defined on the basis of clinical efficacy, evidence and utility. Experts of international repute from Australia, Belgium, Czech Republic, France, Germany, Italy, Netherlands, and UK participated in this exercise. PMID:24814362

  16. Contrasting responses of root morphology and root-exuded organic acids to low phosphorus availability in three important food crops with divergent root traits

    Wang, Yan-Liang; Almvik, Marit; Clarke, Nicholas; Eich-Greatorex, Susanne; Øgaard, Anne Falk; Krogstad, Tore; Lambers, Hans; Clarke, Jihong Liu

    2015-01-01

    Phosphorus (P) is an important element for crop productivity and is widely applied in fertilizers. Most P fertilizers applied to land are sorbed onto soil particles, so research on improving plant uptake of less easily available P is important. In the current study, we investigated the responses in root morphology and root-exuded organic acids (OAs) to low available P (1 μM P) and sufficient P (50 μM P) in barley, canola and micropropagated seedlings of potato—three important food crops with ...

  17. Intravitreal Combination of Dexamethasone Sodium Phosphate and Bevacizumab in The Treatment of Exudative AMD

    Vakalis, N.; Echiadis, G.; Pervena, A.; Deligiannis, I.; Kavalarakis, E.; S. Giannikakis; I. Papaefthymiou

    2015-01-01

    The purpose of this study is to investigate the efficacy and safety of intravitreal dexamethasone sodium phosphate (DSP) combined with bevacizumab for the treatment of neovascular age-related macular degeneration (AMD). In this non comparative case study, 30 eyes of 27 patients with CNV due to AMD received intravitreal DSP (0.2 mg) and bevacizumab (1.25 mg) during a 6-month PRN (pro re nata) dosing regimen. Visual acuity, macular thickness and intraocular pressure (IOP) were monitored and rec...

  18. MicroRNA profiling in human neutrophils during bone marrow granulopoiesis and in vivo exudation

    Larsen, Maria T; Hother, Christoffer; Häger, Mattias;

    2013-01-01

    The purpose of this study was to describe the microRNA (miRNA) expression profiles of neutrophils and their precursors from the initiation of granulopoiesis in the bone marrow to extravasation and accumulation in skin windows. We analyzed three different cell populations from human bone marrow......, polymorphonuclear neutrophil (PMNs) from peripheral blood, and extravasated PMNs from skin windows using the Affymetrix 2.0 platform. Our data reveal 135 miRNAs differentially regulated during bone marrow granulopoiesis. The majority is differentially regulated between the myeloblast/promyelocyte (MB/PM) and...

  19. Antitumor activity of fermented noni exudates (fNE) and its fractions

    Noni (Morinda citrifolia) has been extensively used in folk medicine by Polynesians for over 2000 years and recent studies have shown that noni has a wide spectrum of therapeutic activities including inhibition of angiogenesis, anti-inflammatory effects, and anti-cancer activities. We recently repor...

  20. Diagnostic accuracy and safety of semirigid thoracoscopy in exudative pleural effusions in Denmark

    Willendrup, Fatin; Bødtger, Uffe; Colella, Sara;

    2014-01-01

    March 1, 2009 to September 1, 2013 in Denmark. RESULTS: Sixty-nine patients were retrospectively studied. In 13 patients it was not possible to perform the scheduled MT, in 9 cases due to an insufficient pneumothorax, in 3 due to an insufficient pleural effusion, and in 1 due to a purulent pleuritis. In...

  1. Pharmacological study of radioactive-gold colloid transport by blood and by serous exudate

    After giving the essential physico-chemical properties of the colloids, the author considers the biological role of these substances and, in connection with their transport by the blood, their capture by elements of the reticula-endothelial system. A summary is given of present knowledge concerning the role of serous proteins in the transport of substances, particularly that of radio-active colloidal gold. The blood fractions which can take part in colloidal gold transport are the red blood corpuscles, the leukocytes and histiocytic elements as well as the plasma. The radioactive distribution in these various fractions is obtained by autoradiography of blood sediments. After showing the importance of the role of the plasma in radioactive particle transport, the author, describes the attempts made to detect a possible of colloidal gold 198 on the various serous proteins using various methods of separation. The ''in vitro'' and ''in vivo'' bonds between colloidal gold-198 particles and either the serous proteins or healthy specimens or the effusion liquids of pathological origin in man, or due to an experimental inflammation with carregenin in the rat, have been studied. The bonding appears to be effective because of the protective macromolecular layer formed by the gelatine. The different positions of the colloidal grains on the electrophoregram can only be explained by their different physico-chemical characteristics. Gold in the ionic form, on the other hand, is combined only with the albumen is the amount metal present does not exceed a certain value. (author)

  2. Effect of Alternaria solani exudates on resistant and susceptible potato cultivars from two different pathogen isolates

    The resistance phenotypes of two potato cultivars to two isolates of Alternaria solani, causal agent of early blight, were studied under greenhouse conditions. The two isolates contain varying degrees of aggressiveness on both susceptible and resistant phenotypes of potatoes. A bioassay was used to ...

  3. Carbon content and C:N ratio of transparent exopolymeric particles (TEP) produced by bubbling exudates of diatoms

    Mari, Xavier

    1999-01-01

    The carbon content of transparent exopolymeric particles (TEP) was measured in the laboratory in particles produced by bubbling exudates of the diatom Thalassiosira weissflogii, grown under nitrogen non-limited conditions (N:P = 7). The carbon content of these particles (TEP-C) appears to vary as a function of their size according to TEP-C = 0.25 x 10-6 r2.55 (µg C TEP-1), where r is the equivalent spherical radius of the TEP particle (µm). This relationship implies that TEP are fractal aggre...

  4. Effect of Soil Moisture on Release of Low-MolecularWeight Organic Acids in Root Exudates and the Accumulation of Iron in Root Apoplasm of Peanut

    2000-01-01

    A three-compartments rhizobox was designed and used to study the low-molecular-weight organic acids in root exudates and the root apoplastic iron of "lime-induced chlorosis" peanut grown on a calcareous soil in relation to different soil moisture conditions. Results showed that chlorosis of peanuts developed under condition of high soil moisture level (250 g kg-1), while peanuts grew well and chlorosis did not develop when soil moisture was managed to a normal level (150 g kg-1). The malic acid, maleic acid and succinic acid contents of chlorotic peanut increased by 108.723, 0.029 and 22.446μg cm-2, respectively,compared with healthy peanuts. The content of citric acid and fumaric acid also increased in root exudates of chlorotic peanuts. On Days 28 and 42 of peanut growth, the accumulation of root apoplastic iron in chlorotic peanuts was higher than that of healthy peanuts. From Day 28 to Day 42, the mobilization percentages of chlorotic peanuts and healthy peanuts to root apoplastic iron were almost the same, being 52.4% and 52.8%,respectively, indicating that the chlorosis might be caused by the inactivation of iron within peanut plant grown on a calcareous soil under high soil moisture conditions.

  5. Auxin effects on Pb phytoextraction from polluted soils by Tegetes minuta L. and Bidens pilosa L.: Extractive power of their root exudates.

    Salazar, María Julieta; Rodriguez, Judith Hebelen; Cid, Carolina Vergara; Pignata, María Luisa

    2016-07-01

    The principal impediment for Pb uptake by plants is the Casparian strip in roots. It prevents metals reaching the xylem, thereby hampering translocation to the aerial organs. In the root apices, young root cells have thin cell walls and the Casparian strip is not completely developed, which could facilitate Pb uptake by roots at these vulnerable points. However, as the phytotoxic effects of Pb reduce root growth and enhance suberization, entry of Pb into the plant is avoided. We propose that the application of root growth promotors could be an important complement in the phytoextraction of Pb from polluted soils, due to their effects on produced biomass, Pb toxicity, and root exudate production. A greenhouse experiment was carried on to evaluate the auxin application effect on the Pb uptake of Bidens pilosa and Tagetes minuta. These species were sensitive to auxins, but the phytotoxic effect of Pb was not reversed by this treatment. Root exudates capable of extracting Pb were produced only when the species were grown in highly polluted soils, indicating a behavioral response to Pb exposure which is desirable for phytoremediation. PMID:26954477

  6. Plant exudates promote PCB degradation by a rhodococcal rhizobacteria

    Toussaint, Jean-Patrick; Pham, Thi Thanh My; Barriault, Diane; Sylvestre, Michel [Instiut National de la Recherche Scientifique INRS, Laval, QC (Canada). Inst. Armand-Frappier

    2012-09-15

    Rhodococcus erythropolis U23A is a polychlorinated biphenyl (PCB)-degrading bacterium isolated from the rhizosphere of plants grown on a PCB-contaminated soil. Strain U23A bphA exhibited 99% identity with bphA1 of Rhodococcus globerulus P6. We grew Arabidopsis thaliana in a hydroponic axenic system, collected, and concentrated the plant secondary metabolite-containing root exudates. Strain U23A exhibited a chemotactic response toward these root exudates. In a root colonizing assay, the number of cells of strain U23A associated to the plant roots (5.7 x 105 CFU g{sup -1}) was greater than the number remaining in the surrounding sand (4.5 x 104 CFU g{sup -1}). Furthermore, the exudates could support the growth of strain U23A. In a resting cell suspension assay, cells grown in a minimal medium containing Arabidopsis root exudates as sole growth substrate were able to metabolize 2,3,4'- and 2,3',4-trichlorobiphenyl. However, no significant degradation of any of congeners was observed for control cells grown on Luria-Bertani medium. Although strain U23A was unable to grow on any of the flavonoids identified in root exudates, biphenyl-induced cells metabolized flavanone, one of the major root exudate components. In addition, when used as co-substrate with sodium acetate, flavanone was as efficient as biphenyl to induce the biphenyl catabolic pathway of strain U23A. Together, these data provide supporting evidence that some rhodococci can live in soil in close association with plant roots and that root exudates can support their growth and trigger their PCB-degrading ability. This suggests that, like the flagellated Gram-negative bacteria, non-flagellated rhodococci may also play a key role in the degradation of persistent pollutants. (orig.)

  7. Exudative Retinal Detachment Treatment in a Patient with Thrombotic Thrombocytopenic Purpura

    Magali Sampo

    2016-02-01

    Full Text Available Purpose: We report a case of unilateral exudative retinal detachment in a patient with thrombotic thrombocytopenic purpura (TTP, without associated hypertension, successfully treated with plasmapheresis. Case Report: A 46-year-old woman with a medical history of TTP presented with unilateral exudative retinal detachment. Biological and radiological assessment eliminated other causes of exudative retinal detachment, including hypertension. Plasma exchange was performed, followed by a rapid improvement in visual acuity and total disappearance of serous detachment. Conclusion: Exudative unilateral retinal detachment is a rare complication of TTP and can be successfully treated by plasma exchange.

  8. THE CLINICAL APPLICATIONS FOR AUTOMATIC DETECTION OF EXUDATES

    K. Wisaeng

    2014-01-01

    Full Text Available Nowadays, the retinal imaging technology has been widely used for segmenting and detecting the exudates in diabetic retinopathy patients. Unfortunately, the retinal images in Thailand are poor-quality images. Therefore, detecting of exudates in a large number by screening programs, are very expensive in professional time and may cause human error. In this study, the clinical applications for detection of exudates from the poor quality retinal image are presented. An application incorporating function, including retinal color normalization, contrast enhancement, noise removal, color space selection and removal of the optic disc, was also designed to standardize the workflow of retinal analysis. Afterward, detection of exudate based on optimal global thresholding and improved adaptive Otsu’s algorithm was applied. Two experiments were conducted to validate the detection performance with local databases and a publicly available DIARETDB1 database. The first experiment showed the average sensitivity, specificity and accuracy of 93.8, 95.3 and 94.9%, respectively. The cross validation results of the second experiment, 60% (53 of the retinal images were used for training and 40% (36 for testing, the sensitivity, specificity and accuracy are 84.2, 85.9 and 85.2%, respectively. This result indicates the proposed clinical application provides an effective tool in the screening of exudates.

  9. Profiling of secondary metabolites in root exudates of Arabidopsis thaliana.

    Strehmel, Nadine; Böttcher, Christoph; Schmidt, Stephan; Scheel, Dierk

    2014-12-01

    To explore the chemical composition of root exudates of the model plant Arabidopsis thaliana a workflow for nontargeted metabolite profiling of the semipolar fraction of root exudates was developed. It comprises hydroponic plant cultivation and sampling of root exudates under sterile conditions, sample preparation by solid-phase extraction and analysis by reversed-phase UPLC/ESI-QTOFMS. Following the established workflow, root exudates of six-week-old plants were profiled and a set of reproducibly occurring molecular features was compiled. To structurally elucidate the corresponding metabolites, accurate mass tandem mass spectrometry and on-line hydrogen/deuterium exchange were applied. Currently, a total of 103 compounds were detected and annotated by elemental composition of which more than 90 were structurally characterized or classified. Among them, 42 compounds were rigorously identified using an authenticated standard. The compounds identified so far include nucleosides, deoxynucleosides, aromatic amino acids, anabolites and catabolites of glucosinolates, dipeptides, indolics, salicylic and jasmonic acid catabolites, coumarins, mono-, di- and trilignols, hydroxycinnamic acid derivatives and oxylipins and exemplify the high chemical diversity of plant root exudates. PMID:25457500

  10. Vegetable exudates as food for Callithrix spp. (Callitrichidae: exploratory patterns.

    Talitha Mayumi Francisco

    Full Text Available Marmosets of the genus Callithrix are specialized in the consumption of tree exudates to obtain essential nutritional resource by boring holes into bark with teeth. However, marmoset preferences for particular tree species, location, type, and other suitable factors that aid in exudate acquisition need further research. In the current study, the intensity of exudate use from Anadenanthera peregrina var. peregrina trees by hybrid marmosets Callithrix spp. groups was studied in five forest fragments in Viçosa, in the state of Minas, Brazil. Thirty-nine A. peregrina var. peregrina trees were examined and 8,765 active and non-active holes were analyzed. The trunk of A. peregrina var. peregrina had a lower number of holes than the canopy: 11% were found on the trunk and 89% were found on the canopy. The upper canopy was the preferred area by Callithrix spp. for obtaining exudates. The intensity of tree exploitation by marmosets showed a moderate-to-weak correlation with diameter at breast height (DBH and total tree height. The overall results indicate that Anadenanthera peregrina var. peregrina provides food resources for hybrid marmosets (Callithrix spp. and these animals prefer to explore this resource on the apical parts of the plant, where the thickness, location, and age of the branches are the main features involved in the acquisition of exudates.

  11. The role of prophylactic ibuprofen and N-acetylcysteine on the level of cytokines in periapical exudates and the post-treatment pain

    Ehsani Maryam

    2012-09-01

    Full Text Available Abstract Background Periapical lesions are inflammatory diseases that result in periapical bone destruction because of host defensive–microbial disturbances. Objective To evaluate the role of prophylactic ibuprofen and N-acetylcysteine (NAC on the levels of tumor necrosis factor alpha (TNF- α, interleukin- 6(IL-6 and IL-17 and post-treatment pain level in chronic periapical lesions. Materials and methods Eighty patients with chronic apical lesions less than 1 cm were randomly assigned to receive NAC tablets (400 mg, ibuprofen tablets (400 mg, NAC (400 mg/ibuprofen (200 mg combination and placebo 90 minutes prior to sampling. Periapical exudates were collected from root canals. TNF- α, IL-6 and IL-17 levels were determined by ELISA and post-treatment pain was assessed using a visual analog scale (VAS. Results There was a significant difference in IL-6 level between ibuprofen group and placebo (p = 0.019. Significant difference in IL-17 level was observed between NAC/ibuprofen combination group and placebo (p = 0.043. Four hours after treatment, a significant difference was observed in VAS pain score between ibuprofen group and placebo (p = 0.017. Eight hours post-treatment, VAS pain score for NAC group was statistically lower than placebo group (p = 0.033. After 12 hours VAS pain score showed a significant decrease in NAC group compared to placebo (p = 0.049. Conclusion The prophylactic ibuprofen and NAC failed to clearly reflect their effect on cytokines levels in exudates of chronic periapical lesions. On the other hand it seems that NAC can be a substitute for ibuprofen in the management of post endodontic pain.

  12. The Role of Prophylactic Ibuprofen and N-Acetylcysteine on the Level of Cytokines in Periapical Exudates and the Post-Treatment Pain

    Seyyed Mohsen Aghajanpour Mir

    2012-09-01

    Full Text Available Background Periapical lesions are inflammatory diseases that result in periapical bone destruction because of host defensive-microbial disturbances. Objective:To evaluate the role of prophylactic ibuprofen and N-acetylcysteine (NAC on the levels of tumor necrosis factor alpha (TNF- alpha, interleukin- 6(IL-6 and IL-17 and post-treatment pain level in chronic periapical lesions. Materials and methods Eighty patients with chronic apical lesions less than 1 cm were randomly assigned to receive NAC tablets (400 mg, ibuprofen tablets (400 mg, NAC (400 mg/ibuprofen (200 mg combination and placebo 90 minutes prior to sampling. Periapical exudates were collected from root canals. TNF- alpha, IL-6 and IL-17 levels were determined by ELISA and posttreatment pain was assessed using a visual analog scale (VAS. Results:There was a significant difference in IL-6 level between ibuprofen group and placebo (p = 0.019. Significant difference in IL-17 level was observed between NAC/ibuprofen combination group and placebo (p = 0.043. Four hours after treatment, a significant difference was observed in VAS pain score between ibuprofen group and placebo (p = 0.017. Eight hours post-treatment, VAS pain score for NAC group was statistically lower than placebo group (p = 0.033. After 12 hours VAS pain score showed a significant decrease in NAC group compared to placebo (p = 0.049. Conclusion:The prophylactic ibuprofen and NAC failed to clearly reflect their effect on cytokines levels in exudates of chronic periapical lesions. On the other hand it seems that NAC can be a substitute for ibuprofen in the management of post endodontic pain

  13. AUTOMATIC RETINA EXUDATES SEGMENTATION WITHOUT A MANUALLY LABELLED TRAINING SET

    Giancardo, Luca [ORNL; Meriaudeau, Fabrice [ORNL; Karnowski, Thomas Paul [ORNL; Li, Yaquin [University of Tennessee, Knoxville (UTK); Tobin Jr, Kenneth William [ORNL; Chaum, Edward [University of Tennessee, Knoxville (UTK)

    2011-01-01

    Diabetic macular edema (DME) is a common vision threatening complication of diabetic retinopathy which can be assessed by detecting exudates (a type of bright lesion) in fundus images. In this work, two new methods for the detection of exudates are presented which do not use a supervised learning step and therefore do not require ground-truthed lesion training sets which are time consuming to create, difficult to obtain, and prone to human error. We introduce a new dataset of fundus images from various ethnic groups and levels of DME which we have made publicly available. We evaluate our algorithm with this dataset and compare our results with two recent exudate segmentation algorithms. In all of our tests, our algorithms perform better or comparable with an order of magnitude reduction in computational time.

  14. IDENTIFITION AND STUDY ON ALLELOPATHY OF SOYBEAN ROOT EXUDATES%大豆根分泌物的鉴定及其化感作用的初步研究

    韩丽梅; 李国权

    2000-01-01

    采用GC-MS分析法,鉴定了由水培试验方法获得的2周、8周大豆根分泌物的二氯甲烷提取物,并对其化感作用进行了初步研究。结果表明:能被二氯甲烷提取出来的根分泌物有有机酸类、醇类、酯类、酮类、醛类、酚类、苯类、烃类等有机化合物,其中包含一些资料报道过的化感物质。与对照比较,2周、8周大豆根分泌物对大豆种子萌发、8周根分泌物对胚根生长未表现出显著抑制作用,但2周根分泌物对胚根生长却表现出极显著的化感抑制作用。上述结果表明,大豆根分泌物中存在化感物质,2周与8周大豆根分泌物的种类和数量有所不同。本文还探讨了大豆根分泌物的化感作用及大豆根分泌物与大豆连作障碍的关系等问题。%Compounds extracted with dichloromethane from soybean rootexudates for two weeks, eight weeks in water-culture were identified and allelopathy were studied by GC-MS analysis. The results showed that: The soybean root exudates extracted with dichloromethane included organic acide, alcohol, ester, acetone, aldehyde, phenol, pheyl, hydrocarbon and so on. Many of which were reported as allelochemicale. Contrast with control, the influence of the soybean root exudates for two weeks, eight weeks on the germination of soybean seeds, for eight weeks on radicle growth did not show significant allelopathy inhibition. But the allelopathy of the soybean root exudates for two weeks on soybean radicle growth showed significant inhibition. The results showed that the allelochemicals exist in the soybean root exudates. The varieties and quantities of soypean root exudates for two weeks are different with those for eight weeks. In addition, the alleleopathy of soybean root exudates and the relationship between soybean root exudates and barrier on soybean continuous and alternate cropping were discussed.

  15. 嫁接西瓜根系分泌物的化感效应及其化感物质的鉴定%Allelopathic effects and identification of allelochemicals in root exudates of grafted watermelons

    郑阳霞; 唐海东; 李焕秀; 严泽生; 郭学君

    2011-01-01

    In order to study the allelopathic effects of root exudates from the watermelons grafted with pumpkin and calabash as rootstocks,effects of root exudates from the watermelons grafted on the seed germination and seedling growth of watermelons were researched.The Allelochemicals of root exudates were detected by GC-MS.The results showed that the seed germination and seedling growth of watermelons were increased when the root exudates were in low concentration,but decreased in high concentration.The root exudates promoted the seed germination and seedling growth of watermelons at 2.5 μL·L-1.The root exudates began to restrain the seed germination and seedling growth of watermelons at 10 μL·L-1.When the concentrations were lower,the root exudates from grafted watermelons had more effects on the seed germination and seedling vegetal promotion than own-rooted watermelons.The inhibiting effect of grafted watermelons was less than that of own-rooted watermelon at high concentration of root exudates.And the identification of the allelochemicals in root exudates of grafted watermelons indicated that the categories and the relative contents were different from the own-root plants.The results showed that grafting changed the categories and the relative contents of root exudate components and changed allelopathic effects.Furthermore,there was obvious grafting superiority.So grafting was one of the effective methods for relieving the continuous cropping obstacles caused by autotoxicity.%为了研究嫁接西瓜根系分泌物的化感效应,采用南瓜、葫芦作砧木嫁接西瓜,研究了嫁接西瓜根系分泌物对西瓜种子萌发和幼苗生长的影响,并对嫁接西瓜根系分泌物中的化感物质进行了GC-MS检测。结果表明,各处理对西瓜种子发芽和幼苗生长均呈现出低促高抑的规律。在根系分泌物浓缩液浓度为2.5μL.L-1时,促进西瓜种子的发芽和幼苗的生长。在浓度为10μL.L-1、20μL.L-1

  16. Transcriptomic profiling of Bacillus amyloliquefaciens FZB42 in response to maize root exudates

    Fan, Ben

    2012-06-21

    AbstractBackgroundPlant root exudates have been shown to play an important role in mediating interactions between plant growth-promoting rhizobacteria (PGPR) and their host plants. Most investigations were performed on Gram-negative rhizobacteria, while much less is known about Gram-positive rhizobacteria. To elucidate early responses of PGPR to root exudates, we investigated changes in the transcriptome of a Gram-positive PGPR to plant root exudates.ResultsBacillus amyloliquefaciens FZB42 is a well-studied Gram-positive PGPR. To obtain a comprehensive overview of FZB42 gene expression in response to maize root exudates, microarray experiments were performed. A total of 302 genes representing 8.2% of the FZB42 transcriptome showed significantly altered expression levels in the presence of root exudates. The majority of the genes (261) was up-regulated after incubation of FZB42 with root exudates, whereas only 41 genes were down-regulated. Several groups of the genes which were strongly induced by the root exudates are involved in metabolic pathways relating to nutrient utilization, bacterial chemotaxis and motility, and non-ribosomal synthesis of antimicrobial peptides and polyketides.ConclusionsHere we present a transcriptome analysis of the root-colonizing bacterium Bacillus amyloliquefaciens FZB42 in response to maize root exudates. The 302 genes identified as being differentially transcribed are proposed to be involved in interactions of Gram-positive bacteria with plants.

  17. Transcriptomic profiling of Bacillus amyloliquefaciens FZB42 in response to maize root exudates

    Fan Ben

    2012-06-01

    Full Text Available Abstract Background Plant root exudates have been shown to play an important role in mediating interactions between plant growth-promoting rhizobacteria (PGPR and their host plants. Most investigations were performed on Gram-negative rhizobacteria, while much less is known about Gram-positive rhizobacteria. To elucidate early responses of PGPR to root exudates, we investigated changes in the transcriptome of a Gram-positive PGPR to plant root exudates. Results Bacillus amyloliquefaciens FZB42 is a well-studied Gram-positive PGPR. To obtain a comprehensive overview of FZB42 gene expression in response to maize root exudates, microarray experiments were performed. A total of 302 genes representing 8.2% of the FZB42 transcriptome showed significantly altered expression levels in the presence of root exudates. The majority of the genes (261 was up-regulated after incubation of FZB42 with root exudates, whereas only 41 genes were down-regulated. Several groups of the genes which were strongly induced by the root exudates are involved in metabolic pathways relating to nutrient utilization, bacterial chemotaxis and motility, and non-ribosomal synthesis of antimicrobial peptides and polyketides. Conclusions Here we present a transcriptome analysis of the root-colonizing bacterium Bacillus amyloliquefaciens FZB42 in response to maize root exudates. The 302 genes identified as being differentially transcribed are proposed to be involved in interactions of Gram-positive bacteria with plants.

  18. Enhancement of Phloem Exudation from Fraxinus uhdei Wenz. (Evergreen Ash) using Ethylenediaminetetraacetic Acid.

    Costello, L R; Bassham, J A; Calvin, M

    1982-01-01

    Ethylenediaminetetraacetic acid (EDTA) enhanced the exudation of (14)C-labeled assimilates from excised leaflets and whole plant specimens of Fraxinus uhdei Wenz. A 2 millimolar EDTA concentration was found to be most effective in promoting exudation from excised leaflets, while 10 millimolar EDTA was most effective in whole plants experiments. Exudation rate reached a maximum after 24 hours in both experiments. The continuous presence of EDTA throughout the treatment period was required for maximum exudation from excised leaflets. Stachyose, raffinose, verbascose, and sucrose were the principal compounds found to occur in exudate samples. These compounds are typically transported in sieve elements of various Fraxinus species suggesting the exudate was of phloem origin. Electron microscope studies of petiolule sieve plate pores from excised leaflets showed substantially less callose appearing after treatment with EDTA than after H(2)O treatment. It is suggested that EDTA enhances phloem exudation by inhibiting or reducing callose formation in sieve plate pores. The exudation enhancement technique described for whole plant specimens is suggested as a useful means of collecting phloem sap and studying translocation in woody plants. PMID:16662189

  19. Enhancement of phloem exudation from Fraxinus uhdei Wenz. (evergreen ash) using ethylenediaminetetraacetic acid

    Ethylenediaminetetraacetic acid (EDTA) enhanced the exudation of 14C-labeled assimilates from excised leaflets and whole plant specimens of Fraxinus uhdei Wenz. A 2 millimolar EDTA concentration was found to be most effective in promoting exudation from excised leaflets, while 10 millimolar EDTA was most effective in whole plants experiments. Exudation rate reached a maximum after 24 hours in both experiments. The continuous presence of EDTA throughout the treatment period was required for maximum exudation from excised leaflets. Stachyose, raffinose, verbascose, and sucrose were the principal compounds found to occur in exudate samples. These compounds are typically transported in sieve elements of various Fraxinus species suggesting the exudate was of phloem orgin. Electron microscope studies of petiolule sieve plate pores from excisd leaflets showed substantially less callose appearing after treatment with EDTA than after H2O treatment. It is suggested that EDTA enhances phloem exudation by inhibiting or reducing callose formation in sieve plate pores. The exudation enhancement technique described for whole plant specimens is suggested as a useful means of collecting phloem sap and studying translocation in woody plants

  20. Enhancement of phloem exudation from Fraxinus uhdei Wenz. (evergreen ash) using ethylenediaminetetraacetic acid

    Costello, L.R.; Bassham, J.A., Calvin, M.

    1982-01-01

    Ethylenediaminetetraacetic acid (EDTA) enhanced the exudation of /sup 14/C-labeled assimilates from excised leaflets and whole plant specimens of Fraxinus uhdei Wenz. A 2 millimolar EDTA concentration was found to be most effective in promoting exudation from excised leaflets, while 10 millimolar EDTA was most effective in whole plants experiments. Exudation rate reached a maximum after 24 hours in both experiments. The continuous presence of EDTA throughout the treatment period was required for maximum exudation from excised leaflets. Stachyose, raffinose, verbascose, and sucrose were the principal compounds found to occur in exudate samples. These compounds are typically transported in sieve elements of various Fraxinus species suggesting the exudate was of phloem orgin. Electron microscope studies of petiolule sieve plate pores from excisd leaflets showed substantially less callose appearing after treatment with EDTA than after H/sub 2/O treatment. It is suggested that EDTA enhances phloem exudation by inhibiting or reducing callose formation in sieve plate pores. The exudation enhancement technique described for whole plant specimens is suggested as a useful means of collecting phloem sap and studying translocation in woody plants.

  1. Enhancement of Phloem Exudation from Fraxinus uhdei Wenz. (Evergreen Ash) using Ethylenediaminetetraacetic Acid 1

    Costello, L. R.; Bassham, James A.; Calvin, Melvin

    1982-01-01

    Ethylenediaminetetraacetic acid (EDTA) enhanced the exudation of 14C-labeled assimilates from excised leaflets and whole plant specimens of Fraxinus uhdei Wenz. A 2 millimolar EDTA concentration was found to be most effective in promoting exudation from excised leaflets, while 10 millimolar EDTA was most effective in whole plants experiments. Exudation rate reached a maximum after 24 hours in both experiments. The continuous presence of EDTA throughout the treatment period was required for maximum exudation from excised leaflets. Stachyose, raffinose, verbascose, and sucrose were the principal compounds found to occur in exudate samples. These compounds are typically transported in sieve elements of various Fraxinus species suggesting the exudate was of phloem origin. Electron microscope studies of petiolule sieve plate pores from excised leaflets showed substantially less callose appearing after treatment with EDTA than after H2O treatment. It is suggested that EDTA enhances phloem exudation by inhibiting or reducing callose formation in sieve plate pores. The exudation enhancement technique described for whole plant specimens is suggested as a useful means of collecting phloem sap and studying translocation in woody plants. Images PMID:16662189

  2. Exudative epidermitis in pigs caused by toxigenic Staphylococcus chromogenes

    Andresen, Lars Ole; Ahrens, Peter; Daugaard, Lise;

    2005-01-01

    Staphylococcus chromogenes is closely related to Staphylococcus hyicus, which is recognised as the causative agent of exudative epidermitis (EE) in pigs. S. chromogenes is part of the normal skin flora of pigs, cattle and poultry and has so far been considered non-pathogenic to pigs. A strain of S...

  3. Stellate nonhereditary idiopathic foveomacular retinoschisis concomitant to exudative maculopathies.

    Casalino, G; Upendran, M; Bandello, F; Chakravarthy, U

    2016-05-01

    PurposeTo report the clinical course of patients presenting with stellate nonhereditary idiopathic foveomacular retinoschisis (SNIFR) concomitant with exudative maculopathies.MethodsRetrospective case series. Multimodal imaging findings, including spectral-domain optical coherence tomography (SD-OCT) were reviewed. Genetic testing for the RS1 gene was performed in one patient.ResultsWe identified two female patients who fit the definition of SNIFR and presented with concomitant neovascular age-related macular degeneration (n-AMD). In both the patients, SD-OCT showed exudative macular features and splitting (bilateral in patient 1, unilateral in patient 2) of the outer plexiform layer (OPL) in the macula with no other evidence of hereditary or an acquired predisposing condition. Genetic testing excluded mutation of RS1 gene in patient 1. The fundi of both the patients showed characteristic signs of active choroidal neovascularization (CNV) and following anti-VEGF treatment, visual acuity improved and CNV-related exudative changes resolved. However, the split along the OPL remained unaltered.ConclusionsSNIFR may be associated with n-AMD. It is important to recognise the presence of retinoschisis when there is other exudative pathology as the former may be misinterpreted as intraretinal fluid, prompting unnecessary treatment. PMID:26915743

  4. Elimination of browning exudate and in vitro development of shoots in Pistacia vera L. cv. mateur and Pistacia atlantica Desf. Culture

    M. I. Trujillo

    2014-02-01

    Full Text Available We report diminution and/or elimination of browning exudate followed by in vitro establishment of in Pistacia vera cv. mateur and Pistacia atlantica explants. Soaking P. vera cv. mateur explants prior to culture in L-cysteine HCl for 15 min (100 µM inhibits blackening of the modified Murashige and Skoog medium - MS + 400 mg/l NH4NO3 - and of the explants; while shoot formation was increased. The browning in P. vera cv. mateur and P. atlantica explants dissolved when modified MS and Quoirin and Lepoivre - QL.4 - media were supplemented with activated charcoal (from 1 to 3 g l-1 and with 4 and 8 days of darkness. These treatments were enough to eliminate browning from the explants and to improve the shoots elongation, but symptoms of chlorosis were detected. On the other hand, AgNO3 (from 15 to 40 µ1V1 showed a very strong antibrowning effect on the medium and explants of P. atlantica. Thus shoot organogenesis was best achieved and the developing sturdy shoots had large and green leaves.

  5. Association between variants A69S in ARMS2 gene and response to treatment of exudative AMD: a meta-analysis.

    Hu, Zizhong; Xie, Ping; Ding, Yuzhi; Yuan, Dongqing; Liu, Qinghuai

    2015-05-01

    A study was undertaken to investigate the association between A69S in age-related maculopathy susceptibility 2 (ARMS2) and the response to anti-angiogenesis treatment in exudative age-related macular degeneration (AMD). A literature-based meta-analysis was performed of studies relevant to A69S and the response to anti-angiogenesis treatment. PubMed, Web of Science, China National Knowledge Infrastructure (CNKI) and Sinomed databases were used to retrieve articles up to July 2014. Pooled ORs and 95% CIs were estimated using fixed and random effects models in Stata V.9.0. Q-statistic testing was used to assess heterogeneity. Twelve articles comprising 2389 cases were included in the final meta-analysis. The analysis of the overall population indicated a statistically significant association between A69S and the response to anti-angiogenesis treatment in exudative AMD (GG vs TT: OR 1.34 (95% CI 1.01 to 1.77), p=0.039; GT vs TT: OR 1.58 (95% CI 1.08 to 2.31), p=0.018; GG+GT vs TT: OR 1.74 (95% CI 1.19 to 2.52), p=0.004). In subgroup analysis, A69S appeared more likely to be a predictor for anti-angiogenic response in the East Asian population (GG vs TT: OR 1.65 (95% CI 1.02 to 2.68), p=0.042; GT vs TT: OR 1.66 (95% CI 1.17 to 2.37), p=0.005; GG+GT vs TT: OR 1.82 (95% CI 1.07 to 3.10), p=0.027; G vs T: OR 1.56 (95% CI 1.01 to 2.41)). However, no statistical significance was found in the Caucasian subgroup analysis. This study shows an association between A69S polymorphism in the ARMS2 gene and the anti-angiogenesis treatment response. A69S could be considered predictive of the anti-angiogenic effects, especially in Asian populations. PMID:25185256

  6. Metabolite Profiling of Root Exudates of Common Bean under Phosphorus Deficiency

    Keitaro Tawaraya

    2014-07-01

    Full Text Available Root exudates improve the nutrient acquisition of plants and affect rhizosphere microbial communities. The plant nutrient status affects the composition of root exudates. The purpose of this study was to examine common bean (Phaseolus vulgaris L. root exudates under phosphorus (P deficiency using a metabolite profiling technique. Common bean plants were grown in a culture solution at P concentrations of 0 (P0, 1 (P1 and 8 (P8 mg P L−1 for 1, 10 and 20 days after transplanting (DAT. Root exudates were collected, and their metabolites were determined by capillary electrophoresis time-of-flight mass spectrometry (CE-TOF MS. The shoot P concentration and dry weight of common bean plants grown at P0 were lower than those grown at P8. One hundred and fifty-nine, 203 and 212 metabolites were identified in the root exudates, and 16% (26/159, 13% (26/203 and 9% (20/212 of metabolites showed a P0/P8 ratio higher than 2.0 at 1, 10 and 20 DAT, respectively. The relative peak areas of several metabolites, including organic acids and amino acids, in root exudates were higher at P0 than at P8. These results suggest that more than 10% of primary and secondary metabolites are induced to exude from roots of common bean by P deficiency.

  7. Dosagem de proteínas totais e desidrogenase lática para o diagnóstico de transudatos e exsudatos pleurais: redefinindo o critério clássico com uma nova abordagem estatística Determination of total proteins and lactate dehydrogenase for the diagnosis of pleural transudates and exudates: redefining the classical criterion with a new statistical approach

    Bernardo Henrique Ferraz Maranhão; Cyro Teixeira da Silva Junior; Antonio Monteiro da Silva Chibante; Gilberto Perez Cardoso

    2010-01-01

    OBJETIVO: Propor um novo critério de classificação para a diferenciação entre exsudatos e transudatos pleurais através da dosagem de proteínas totais no líquido pleural (PT-LP) e de desidrogenase lática no líquido pleural (DHL-LP) exclusivamente, assim como comparar o rendimento diagnóstico entre esse novo critério com o critério clássico. MÉTODOS: Estudo observacional, transversal de tipo individualizado, no qual foram selecionados 181 pacientes com derrame pleural tratados em dois hospitais...

  8. Trichoderma spp. Improve growth of Arabidopsis seedlings under salt stress through enhanced root development, osmolite production, and Na⁺ elimination through root exudates.

    Contreras-Cornejo, Hexon Angel; Macías-Rodríguez, Lourdes; Alfaro-Cuevas, Ruth; López-Bucio, José

    2014-06-01

    Salt stress is an important constraint to world agriculture. Here, we report on the potential of Trichoderma virens and T. atroviride to induce tolerance to salt in Arabidopsis seedlings. We first characterized the effect of several salt concentrations on shoot biomass production and root architecture of Arabidopsis seedlings. We found that salt repressed plant growth and root development in a dose-dependent manner by blocking auxin signaling. Analysis of the wild type and eir1, aux1-7, arf7arf19, and tir1abf2abf19 auxin-related mutants revealed a key role for indole-3-acetic acid (IAA) signaling in mediating salt tolerance. We also found that T. virens (Tv29.8) and T. atroviride (IMI 206040) promoted plant growth in both normal and saline conditions, which was related to the induction of lateral roots and root hairs through auxin signaling. Arabidopsis seedlings grown under saline conditions inoculated with Trichoderma spp. showed increased levels of abscissic acid, L-proline, and ascorbic acid, and enhanced elimination of Na⁺ through root exudates. Our data show the critical role of auxin signaling and root architecture to salt tolerance in Arabidopsis and suggest that these fungi may enhance the plant IAA level as well as the antioxidant and osmoprotective status of plants under salt stress. PMID:24502519

  9. Subretinal lipid exudation associated with untreated choroidal melanoma

    C K Minija

    2011-01-01

    Full Text Available Subretinal lipid exudation in an untreated choroidal melanoma is very rare. It is seen following plaque radiotherapy in choroidal melanoma. There is only one case report of untreated choroidal melanoma with massive lipid exudation in a patient with metastatic hypernephroma. We report here a rare case of untreated choroidal melanoma with lipid exudation. Subretinal exudation that is rarely seen following plaque brachytherapy was noted at the borders of this untreated tumor. Lipid exudation partially resolved following brachytherapy.

  10. Biological oxygen demand optode analysis of coral reef-associated microbial communities exposed to algal exudates

    AK Gregg

    2013-07-01

    Full Text Available Algae-derived dissolved organic matter has been hypothesized to induce mortality of reef building corals. One proposed killing mechanism is a zone of hypoxia created by rapidly growing microbes. To investigate this hypothesis, biological oxygen demand (BOD optodes were used to quantify the change in oxygen concentrations of microbial communities following exposure to exudates generated by turf algae and crustose coralline algae (CCA. BOD optodes were embedded with microbial communities cultured from Montastraea annularis and Mussismilia hispida, and respiration was measured during exposure to turf and CCA exudates. The oxygen concentrations along the optodes were visualized with a low-cost Submersible Oxygen Optode Recorder (SOOpR system. With this system we observed that exposure to exudates derived from turf algae stimulated higher oxygen drawdown by the coral-associated bacteria than CCA exudates or seawater controls. Furthermore, in both turf and CCA exudate treatments, all microbial communities (coral-, algae-associated and pelagic contributed significantly to the observed oxygen drawdown. This suggests that the driving factor for elevated oxygen consumption rates is the source of exudates rather than the initially introduced microbial community. Our results demonstrate that exudates from turf algae may contribute to hypoxia-induced coral stress in two different coral genera as a result of increased biological oxygen demand of the local microbial community. Additionally, the SOOpR system developed here can be applied to measure the BOD of any culturable microbe or microbial community.

  11. Combining the genetic algorithm and successive projection algorithm for the selection of feature wavelengths to evaluate exudative characteristics in frozen-thawed fish muscle.

    Cheng, Jun-Hu; Sun, Da-Wen; Pu, Hongbin

    2016-04-15

    The potential use of feature wavelengths for predicting drip loss in grass carp fish, as affected by being frozen at -20°C for 24 h and thawed at 4°C for 1, 2, 4, and 6 days, was investigated. Hyperspectral images of frozen-thawed fish were obtained and their corresponding spectra were extracted. Least-squares support vector machine and multiple linear regression (MLR) models were established using five key wavelengths, selected by combining a genetic algorithm and successive projections algorithm, and this showed satisfactory performance in drip loss prediction. The MLR model with a determination coefficient of prediction (R(2)P) of 0.9258, and lower root mean square error estimated by a prediction (RMSEP) of 1.12%, was applied to transfer each pixel of the image and generate the distribution maps of exudation changes. The results confirmed that it is feasible to identify the feature wavelengths using variable selection methods and chemometric analysis for developing on-line multispectral imaging. PMID:26617027

  12. A Stable-Isotope Mass Spectrometry-Based Metabolic Footprinting Approach to Analyze Exudates from Phytoplankton

    Mark R. Viant

    2013-10-01

    Full Text Available Phytoplankton exudates play an important role in pelagic ecology and biogeochemical cycles of elements. Exuded compounds fuel the microbial food web and often encompass bioactive secondary metabolites like sex pheromones, allelochemicals, antibiotics, or feeding attractants that mediate biological interactions. Despite this importance, little is known about the bioactive compounds present in phytoplankton exudates. We report a stable-isotope metabolic footprinting method to characterise exudates from aquatic autotrophs. Exudates from 13C-enriched alga were concentrated by solid phase extraction and analysed by high-resolution Fourier transform ion cyclotron resonance mass spectrometry. We used the harmful algal bloom forming dinoflagellate Alexandrium tamarense to prove the method. An algorithm was developed to automatically pinpoint just those metabolites with highly 13C-enriched isotope signatures, allowing us to discover algal exudates from the complex seawater background. The stable-isotope pattern (SIP of the detected metabolites then allowed for more accurate assignment to an empirical formula, a critical first step in their identification. This automated workflow provides an effective way to explore the chemical nature of the solutes exuded from phytoplankton cells and will facilitate the discovery of novel dissolved bioactive compounds.

  13. Diets high in fruits and low in gum exudates promote the occurrence and development of dental disease in pygmy slow loris (Nycticebus pygmaeus).

    Cabana, Francis; Nekaris, K A I

    2015-11-01

    Asian slow lorises are found in zoos and rescue centres worldwide with Nycticebus pygmaeus, the pygmy slow loris, boasting the largest population in captivity. Diet are reportedly high in fruit and concentrates and low in insects and exudates. Wild feeding studies place insects, nectar, and gums as the most important diet components. Captive populations also show high incidences of health afflictions, many of which may be caused by nutrition. Our study, aims at identifying a causative agent within the diets of N. pygmaeus in regards to diseases prominent within captive populations. We sent out 55 diet and health questionnaires to institutions worldwide. Returned diets were nutritionally analyzed. Nutrient values and proportions of each ingredient were used in a principle components analysis. Resulting factors were used as variables in a binary logistic regression (BLR), with dental disease as the dependent variable. 39 questionnaires were returned with a total of 47 diets. 20 (51.7%) institutions reported the presence of diseases with dental issues being prominent. Factors that were significant in the principle components analysis included gum, nectar, protein, acid detergent fibre, calcium, ash, phosphorus, potassium, Ca:P, magnesium, vitamin D, and energy. Gum was the only significant predictor in the BLR. Lastly, a chi square test for association was performed with the presence of dental disease as the dependent variable and the amount of fruit in the diet. The combination of high fruits and little to no gum promotes the occurrence of dental diseases. Current captive diets do not reflect the evolutionary adaptations of Nycticebus primates. PMID:26339992

  14. Detection of human immunodeficiency virus using oral mucosal transudate by rapid test

    Bhuvan Jyoti

    2013-01-01

    Settings and Design: OraQuick Rapid HIV-1/2 Diagnostic test was evaluated in sera and oral fluids from 83 subjects. Materials and Methods: The study group comprised of 50 HIV seropositive subjects and the control group comprised of 33 seronegative subjects. Serum samples were collected using the standard phlebotomy technique and oral samples were collected using OraQuick Rapid HIV 1/2 Antibody test OMT collecting device. Statistical Analysis Used: The statistical analysis was done using statistical package for social sciences version 16.0, SPSS Inc., 233 South Wacker Drive, 11 th Floor, Chicago, IL 60606-6412. The Sensitivity, specificity, positive predictive value, negative predictive value were used. Results: All the subjects who tested either positive/reactive or negative/non-reactive with Western blot/enzyme-linked immunosorbent assay (ELISA produced similar results with Rapid test using OMT in study, our study also revealed that the subjects whether on anti-retroviral therapy or not had 100% sensitivity and specificity with the Rapid test using OMT. Conclusions: The Rapid test using OMT is highly accurate as the diagnostic efficacy in our study was 100% for HIV antibody detection and produced similar results to that of conventional Western blot/ELISA tests.

  15. Root Exudation: The Ecological Driver of Hydrocarbon Rhizoremediation

    Fanny Rohrbacher

    2016-03-01

    Full Text Available Rhizoremediation is a bioremediation technique whereby microbial degradation of organic contaminants occurs in the rhizosphere. It is considered to be an effective and affordable “green technology” for remediating soils contaminated with petroleum hydrocarbons. Root exudation of a wide variety of compounds (organic, amino and fatty acids, carbohydrates, vitamins, nucleotides, phenolic compounds, polysaccharides and proteins provide better nutrient uptake for the rhizosphere microbiome. It is thought to be one of the predominant drivers of microbial communities in the rhizosphere and is therefore a potential key factor behind enhanced hydrocarbon biodegradation. Many of the genes responsible for bacterial adaptation in contaminated soil and the plant rhizosphere are carried by conjugative plasmids and transferred among bacteria. Because root exudates can stimulate gene transfer, conjugation in the rhizosphere is higher than in bulk soil. A better understanding of these phenomena could thus inform the development of techniques to manipulate the rhizosphere microbiome in ways that improve hydrocarbon bioremediation.

  16. Identifying root exudates in field contaminated soil systems

    Rosenfeld, C.; Martinez, C. E.

    2012-12-01

    Carbon (C) compounds exuded from plant roots comprise a significant and reactive fraction of belowground C pools. These exudates substantially alter the soil directly surrounding plant roots and play a vital role in the global C cycle, soil ecology, and ecosystem mobility of both nutrients and contaminants. In soils, the solubility and bioavailability of metals such as iron, zinc, and cadmium are intricately linked to the quantity and chemical characteristics of the C compounds allocated to the soil by plants. Cadmium (Cd), a toxic heavy metal, forms stronger bonds with reduced S- and N-containing compounds than with carboxylic acids, which may influence exudate composition in hyperaccumulator and tolerant plants grown in Cd contaminated soils. We hypothesize that hyperaccumulator plants will exude a larger quantity of aromatic N and chelating di- and tri-carboxylic acid molecules, while plants that exclude heavy metals from uptake will exude a larger proportion of reduced S containing molecules. This study examines how a variety of techniques can measure the low concentrations of complex organic mixtures exuded by hyperaccumulator and non-hyperaccumulator plants grown in Cd-contaminated soils. Two congeneric plants, Thlaspi caerulescens (Ganges ecotype), and T. caerulescens (Prayon ecotype) were grown in 0.5 kg pots filled with Cd-contaminated field soils from Chicago, IL. Field soils were contaminated as a result of the application of contaminated biosolids in the 1960's and 1970's. Pots were fitted for rhizon soil moisture samplers, micro-lysimeters developed for in situ collection of small volumes in unsaturated soils, prior to planting. Plants were grown for 8 weeks before exudate collection. After the 8 weeks of growth, a pulse-chase isotope tracer method using the C stable isotope, 13C, was employed to differentiate plant-derived compounds from background soil and microbial-derived compounds. Plants were placed in a CO2 impermeable chamber, and the soil

  17. Automatic Detection of Exudates in Retinal Fundus Images using Differential Morphological Profile

    Shraddha Tripathi

    2013-06-01

    Full Text Available This paper presents an automatic method for exudate detection from colour fundus imagesbased on Differential Morphological Profile (DMP.The detection of exudates is important for the identification of eye diseases such as diabetic retinopathy. The method involves of three main phases. Inthe first phase, pre processing tasks like Gaussian smoothing and contrast enhancement is done. In the second phase, DMP is applied on the pre-processed image. The image obtained from DMP containshighlighted bright regions consisting of exudates and optic disc. In the next phase, feature extraction based on location of optic disc, shape index and area is done to obtain actual exudates. The performance of the proposed method is evaluated by applying it on the DIARETDB1 database. The specificity,sensitivity and PPV of the proposed method were compared with two other methods. The results showthat the proposed method gives better results than the other conventional methods.

  18. Effect of intravitreal bevacizumab on diabetic macular edema with hard exudates

    Lee, Won Ki

    2014-01-01

    Sohee Jeon, Won Ki LeeDepartment of Ophthalmology, Seoul St Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, KoreaBackground: We evaluated the efficacy of intravitreal bevacizumab on diabetic macular edema with subfoveal and perifoveal hard exudates.Materials and methods: Eleven eyes (11 patients) exhibiting diabetic macular edema with subfoveal and perifoveal hard exudates were included in this prospective, nonrandomized interventional pilot study. All...

  19. Effect of intravitreal bevacizumab on diabetic macular edema with hard exudates

    Jeon S.; Lee WK

    2014-01-01

    Sohee Jeon, Won Ki LeeDepartment of Ophthalmology, Seoul St Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, KoreaBackground: We evaluated the efficacy of intravitreal bevacizumab on diabetic macular edema with subfoveal and perifoveal hard exudates.Materials and methods: Eleven eyes (11 patients) exhibiting diabetic macular edema with subfoveal and perifoveal hard exudates were included in this prospective, nonrandomized interventional pilot study. All pat...

  20. Exudative Inflammatory Eye Response in Cataract Surgery: Current View on the Problem

    Belousova N.Y.

    2011-01-01

    There has been analyzed one of the most frequent and serious complications of cataract surgery — exudative inflammatory response (EIR) of eye. There has been presented current view on etiopathogenesis of the condition, classifications and the description of clinical presentation of various EIR types have been given. Known techniques of prognosis and prevention of postoperative exudative uveites have been presented. There have been given present methods of complex treatment of eye EIR: drug tr...

  1. Microbial Products Trigger Amino Acid Exudation from Plant Roots1

    Phillips, Donald A.; Fox, Tama C.; King, Maria D.; Bhuvaneswari, T.V.; Teuber, Larry R.

    2004-01-01

    Plants naturally cycle amino acids across root cell plasma membranes, and any net efflux is termed exudation. The dominant ecological view is that microorganisms and roots passively compete for amino acids in the soil solution, yet the innate capacity of roots to recover amino acids present in ecologically relevant concentrations is unknown. We find that, in the absence of culturable microorganisms, the influx rates of 16 amino acids (each supplied at 2.5 μm) exceed efflux rates by 5% to 545% in roots of alfalfa (Medicago sativa), Medicago truncatula, maize (Zea mays), and wheat (Triticum aestivum). Several microbial products, which are produced by common soil microorganisms such as Pseudomonas bacteria and Fusarium fungi, significantly enhanced the net efflux (i.e. exudation) of amino acids from roots of these four plant species. In alfalfa, treating roots with 200 μm phenazine, 2,4-diacetylphloroglucinol, or zearalenone increased total net efflux of 16 amino acids 200% to 2,600% in 3 h. Data from 15N tests suggest that 2,4-diacetylphloroglucinol blocks amino acid uptake, whereas zearalenone enhances efflux. Thus, amino acid exudation under normal conditions is a phenomenon that probably reflects both active manipulation and passive uptake by microorganisms, as well as diffusion and adsorption to soil, all of which help overcome the innate capacity of plant roots to reabsorb amino acids. The importance of identifying potential enhancers of root exudation lies in understanding that such compounds may represent regulatory linkages between the larger soil food web and the internal carbon metabolism of the plant. PMID:15347793

  2. Root exudation of phytosiderophores from soil-grown wheat.

    Oburger, Eva; Gruber, Barbara; Schindlegger, Yvonne; Schenkeveld, Walter D C; Hann, Stephan; Kraemer, Stephan M; Wenzel, Walter W; Puschenreiter, Markus

    2014-09-01

    For the first time, phytosiderophore (PS) release of wheat (Triticum aestivum cv Tamaro) grown on a calcareous soil was repeatedly and nondestructively sampled using rhizoboxes combined with a recently developed root exudate collecting tool. As in nutrient solution culture, we observed a distinct diurnal release rhythm; however, the measured PS efflux was c. 50 times lower than PS exudation from the same cultivar grown in zero iron (Fe)-hydroponic culture. Phytosiderophore rhizosphere soil solution concentrations and PS release of the Tamaro cultivar were soil-dependent, suggesting complex interactions of soil characteristics (salinity, trace metal availability) and the physiological status of the plant and the related regulation (amount and timing) of PS release. Our results demonstrate that carbon and energy investment into Fe acquisition under natural growth conditions is significantly smaller than previously derived from zero Fe-hydroponic studies. Based on experimental data, we calculated that during the investigated period (21-47 d after germination), PS release initially exceeded Fe plant uptake 10-fold, but significantly declined after c. 5 wk after germination. Phytosiderophore exudation observed under natural growth conditions is a prerequisite for a more accurate and realistic assessment of Fe mobilization processes in the rhizosphere using both experimental and modeling approaches. PMID:24890330

  3. Miscibility Studies of Cashew Gum and Khaya Gum Exudates in Dilute Solution by Viscometry and FTIR Analysis.

    David E. Arthur; C.E. Gimba; Eddy O. Nnabuk

    2014-01-01

    The FTIR and coefficient of viscosity for Cashew/Khaya blends in deionized water were measured, the changes in specific viscosity of the blends with corresponding effect of temperature and ionic salts, i.e. KCl, KBr and AlCl3 were modeled. The measured parameters were used to estimate other related physical quantities using Huggins, Tanglertpaibul and Rao, Frankel-eyring and Arrhenuis-frankel models etc. these quantities includes the intrinsic viscosity (η), conformation parameter (blaw), sta...

  4. Miscibility Studies of Cashew Gum and Khaya Gum Exudates in Dilute Solution by Viscometry and FTIR Analysis.

    David E. Arthur

    2014-08-01

    Full Text Available The FTIR and coefficient of viscosity for Cashew/Khaya blends in deionized water were measured, the changes in specific viscosity of the blends with corresponding effect of temperature and ionic salts, i.e. KCl, KBr and AlCl3 were modeled. The measured parameters were used to estimate other related physical quantities using Huggins, Tanglertpaibul and Rao, Frankel-eyring and Arrhenuis-frankel models etc. these quantities includes the intrinsic viscosity (η, conformation parameter (blaw, standard Enthalpy and Energy change of blend flow (∆H and ∆E, Huggins parameter (K, Interaction parameter (bm1 were proposed by Higiro et al., to identify the molecular conformation and the interaction arising in solution of gum blends. The peculiar deviation confirmed the structural changes in the solution of the blends, while the FTIR confirmed the formation of physical blends

  5. TableCross: Exuding a Shared Space into Personal Spaces to Encourage Its Voluntary Maintenance

    Nishimoto, Kazushi; Ikenoue, Akari; Shimizu, Koji; Tajima, Tomonori; Tanaka, Yuta; Baba, Yutaka; Wang, Xihong

    2011-01-01

    A shared space should be cooperatively maintained by all users. However, due to social loafing, often nobody maintains it and its condition worsens. We propose exudation of a shared space. Part of a shared space is exuded into personal workspaces so that office workers are forced to subjectively experience the atmosphere of the shared space, even while they remain at their personal workspaces. This paper illustrates the first prototype named “TableCross,” which reflects the degree of disorder...

  6. Early Signs of Exudative Age-Related Macular Degeneration in Asians

    Sasaki, Mariko; Kawasaki, Ryo; Uchida, Atsuro; Koto, Takashi; Shinoda, Hajime; Tsubota, Kazuo; Wong, Tien Yin; Ozawa, Yoko

    2014-01-01

    ABSTRACT Purpose To investigate the relationship between the early signs of age-related macular degeneration (AMD) and the risk of developing exudative AMD (typical AMD or polypoidal choroidal vasculopathy [PCV]) in the fellow eye of Japanese patients with unilateral exudative AMD, focusing particularly on eyes with only pigmentary abnormality. Methods This study is a retrospective observational consecutive case series. We retrospectively reviewed the medical charts of patients who revisited ...

  7. Genetics Home Reference: familial exudative vitreoretinopathy

    ... 2):104-12. Citation on PubMed Robitaille J, MacDonald ML, Kaykas A, Sheldahl LC, Zeisler J, Dubé ... Shukla D, Singh J, Sudheer G, Soman M, John RK, Ramasamy K, Perumalsamy N. Familial exudative vitreoretinopathy ( ...

  8. Genotypic variation in the ability of landraces and commercial cereal varieties to avoid manganese deficiency in soils with limited manganese availability: is there a role for root-exuded phytases?

    George, Timothy S; French, Andrew S; Brown, Lawrie K; Karley, Alison J; White, Philip J; Ramsay, Luke; Daniell, Tim J

    2014-07-01

    The marginal agricultural-systems of the Machair in the Western Isles of Scotland often have limited micronutrient availability because of alkaline soils. Traditional landraces of oats, barley and rye are thought to be better adapted to cope with the limited manganese (Mn) availability of these soils. When commercial cultivars are grown on the Machair, limited Mn-availability reduces crop yield and quality. We hypothesised that traditional cereal landraces selected on the Machair acquire Mn more effectively and that this could be linked to exudation of phytase from roots which would release Mn complexed with inositol phosphates. Growth and Mn-acquisition of five landraces and three commercial cultivars of barley and oats were determined in Machair soil. In addition, root phytase activities were assayed under Mn-starvation and sufficiency in hydroponics. In Machair soil, landraces had greater capacity for acquiring Mn and a greater ability to achieve maximum yield compared to the commercial cultivars. Under Mn-starvation, root phytase exudation was upregulated in all plants, suggesting that this trait might allow cereals to acquire more Mn when Mn-availability is limited. In the landraces, exuded phytase activity related positively to relative Mn-accumulation, whereas in the commercial cultivars this relationship was negative, suggesting that this trait may be secondary to an efficiency trait that has been lost from commercial germplasm by breeding. This research shows that cereal landraces possess traits that could be useful for improving the Mn-acquisition of commercial varieties. Exploiting the genetic diversity of landraces could improve the sustainability of agriculture on marginal calcareous lands globally. PMID:24438182

  9. A review of the influence of root-associating fungi and root exudates on the success of invasive plants

    Cindy Bongard

    2012-01-01

    Plant-fungal interactions are essential for understanding the distribution and abundance of plants species. Recently, arbuscular mycorrhizal fungal (AMF) partners of non-indigenous invasive plants have been hypothesized to be a critical factor influencing the invasion processes. AMF are known to improve nutrient and moisture uptake, as well as disrupt parasitic and pathogenic microbes in the host plant. Such benefits may enable invaders to establish significant and persistent populations in e...

  10. Inhibitory potential of naphthoquinones leached from leaves and exuded from roots of the invasive plant Impatiens glandulifera.

    Ruckli, Regina; Hesse, Katharina; Glauser, Gaetan; Rusterholz, Hans-Peter; Baur, Bruno

    2014-04-01

    Exploring the effects of allelopathic plant chemicals on the growth of native vegetation is essential to understand their ecological roles and importance in exotic plant invasion. Naphthoquinones have been identified as potential growth inhibitors produced by Impatiens glandulifera, an exotic annual plant that recently invaded temperate forests in Europe. However, naphthoquinone release and inhibitory potential have not been examined. We quantified the naphthoquinone content in cotyledons, leaves, stems, and roots from plants of different ages of both the invasive I. glandulifera and native Impatiens noli-tangere as well as in soil extracts and rainwater rinsed from leaves of either plant species by using ultra-high pressure liquid chromatography-mass spectrometry (UHPLC-MS). We identified the compound 2-methoxy-1,4-naphthoquinone (2-MNQ) exclusively in plant organs of I. glandulifera, in resin bags buried into the soil of patches invaded by I. glandulifera, and in rainwater rinsed from its leaves. This indicates that 2-MNQ is released from the roots of I. glandulifera and leached from its leaves by rain. Specific bioassays using aqueous shoot and root extracts revealed a strong inhibitory effect on the germination of two native forest herbs and on the mycelium growth of three ectomycorrhiza fungi. These findings suggest that the release of 2-MNQ may contribute to the invasion success of I. glandulifera and support the novel weapons hypothesis. PMID:24722883