Publications by authors named "Atanasov K"

Polyamines are small aliphatic polycations present in all living organisms. In plants, the most abundant polyamines are putrescine (Put), spermidine (Spd) and spermine (Spm). Polyamine levels change in response to different pathogens, including Pseudomonas syringae pv.

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Polyamines are small polycationic amines whose levels increase during defense. Previous studies support the contribution of the polyamine spermine to defense responses. However, the potential contribution of spermine to pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) has not been completely established.

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In the framework of the research project called fitomatics, we have isolated and characterized a bacterial plant-endophyte from the rhizomes of , hereafter referred to as strain FIT81. The bacterium is Gram negative, rod-shaped with lophotrichous flagella, and catalase- and oxidase-positive. The optimal growth temperature of strain FIT81 is 28 °C, although it can grow within a temperature range of 4-32 °C.

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High ammonium suppresses hybrid incompatibility between Ler and Kas-2 accessions through lowering nitric oxide levels and nitrate reductase activity required for autoimmunity. The immune-related hybrid incompatibility (HI) between Landsberg erecta (Ler) and Kashmir-2 (Kas-2) accessions is due to a deleterious genetic interaction between the RPP1 (RECOGNITION OF PERONOSPORA PARASITICA1)-like Ler locus and Kas-2 alleles of the receptor-like kinase SRF3 (STRUBBELIG RECEPTOR FAMILY 3). The genetic incompatibility is temperature-dependent and leads to constitutive activation of the salicylic acid (SA) pathway, dwarfism and cell death at 14-16 °C.

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SARS-CoV-2 infection may precede and cause various autoimmune and inflammatory diseases, including multisystem inflammatory syndrome in children (MIS-C). Therefore, we aimed to observe the clinical presentation and laboratory, instrumental and other constellations in children with MIS-C, including liver involvement. We present the outcomes from a single-center prospective observational study in which 89 children was included (60 with proven COVID-19, 10 symptomatic with confirmed COVID-19 contact and 19 diagnosed with MIS-C).

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Polyamines are small amines that accumulate during stress and contribute to disease resistance through as yet unknown signaling pathways. Using a comprehensive RNA-sequencing analysis, we show that early transcriptional responses triggered by each of the most abundant polyamines (putrescine, spermidine, spermine, thermospermine and cadaverine) exhibit specific quantitative differences, suggesting that polyamines (rather than downstream metabolites) elicit defense responses. Signaling by putrescine, which accumulates in response to bacteria that trigger effector triggered immunity (ETI) and systemic acquired resistance (SAR), is largely dependent on the accumulation of hydrogen peroxide, and is partly dependent on salicylic acid (SA), the expression of ENHANCED DISEASE SUSCEPTIBILITY (EDS1) and NONEXPRESSOR of PR GENES1 (NPR1).

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Polyamines are involved in defense against pathogenic microorganisms in plants. However, the role of the polyamine putrescine (Put) during plant defense has remained elusive. In this work, we studied the implication of polyamines during pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) in the model species .

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Genetic divergence between populations can lead to reproductive isolation. Hybrid incompatibilities (HI) represent intermediate points along a continuum toward speciation. In plants, genetic variation in disease resistance () genes underlies several cases of HI.

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In the recent years, genetic engineering of polyamine biosynthetic genes has provided evidence for their involvement in plant stress responses and different aspects of plant development. Such approaches are being complemented with the use of reverse genetics, in which mutants affected on a particular trait, tightly associated with polyamines, are isolated and the causal genes mapped. Reverse genetics enables the identification of novel genes in the polyamine pathway, which may be involved in downstream signaling, transport, homeostasis, or perception.

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Guazatine is a potent inhibitor of polyamine oxidase (PAO) activity. In agriculture, guazatine is used as non-systemic contact fungicide efficient in the protection of cereals and citrus fruits against disease. The composition of guazatine is complex, mainly constituted by a mixture of synthetic guanidated polyamines (polyaminoguanidines).

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Early and more recent studies have suggested that some polyamines (PAs), and particularly spermine (Spm), exhibit anti-senescence properties in plants. In this work, we have investigated the role of Arabidopsis Polyamine Oxidase 4 (PAO4), encoding a PA back-conversion oxidase, during dark-induced senescence. Two independent PAO4 (pao4-1 and pao4-2) loss-of-function mutants have been found that accumulate 10-fold higher Spm, and this associated with delayed entry into senescence under dark conditions.

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The family of polyamine oxidases (PAO) in Arabidopsis (AtPAO1-5) mediates polyamine (PA) back-conversion, which reverses the PA biosynthetic pathway from spermine and its structural isomer thermospermine (tSpm) into spermidine and then putrescine. Here, we have studied the involvement of PA back-conversion in Arabidopsis salinity tolerance. AtPAO5 is the Arabidopsis PAO gene member most transcriptionally induced by salt stress.

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Signal transducer and activator of transcription 3 (STAT3) is altered in several epithelial cancers and represents a potential therapeutic target. Here, STAT3 expression, activity and cellular functions were examined in two main histotypes of esophageal carcinomas. In situ, immunohistochemistry for STAT3 and STAT3-Tyr705 phosphorylation (P-STAT3) in esophageal squamous cell carcinomas (ESCC, n=49) and Barrett's adenocarcinomas (BAC, n=61) revealed similar STAT3 expression in ESCCs and BACs (P=0.

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A model is proposed for the organization of mass orthodontic prophylaxis in the integrated pediatric institutions (IPI), covering the following more important activities: I. Follow-up care of the organized pediatric groups in the crêches and nurseries with a view to orthodontic prophylaxis. II.

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67 patients with multiple myeloma with different duration and stage were studied. In 12 patients (17.91%) the onset of the disease was manifested by renal symptoms which were mistaken for primary renal disease.

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The intravenous pulsed treatment with prednisone hemisuccinate of severe forms of systemic lupus erythematosus influences favorably the basic clinical manifestations of the disease--polyarthritis, fever, vasculitis, myocarditis, sialoadenitis. Prednisolone is as efficient as methylprednisolone in the pulsed treatment of patients with systemic lupus erythematosus.

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Streptokinase treatment was carried out in the intensive care unit of III Internal Clinic, the Higher Medical Institute--Plovdiv, on 54 patients, 51 of them with acute myocardial infarction (AMI) and 3 with intermediary coronary syndrome, making use of the preparations streptase (GFR) and avelysin (GDR). A control group of 35 patients with AMI was used. The treatment was initiated with stream administration of heparin 10,000 U and urbazon 20 mg, whereafter streptokinase 1,250,000 U per 1 h was included on that background.

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A survey was performed of that rare hematological disease with a diagnostic therapeutic purpose. A case is reported with hairy-cell leukemia diagnosed while living, with the description of the clinical signs, morphological, cytochemical and immunohematological characteristics of hairy-cell leukemia. The diagnosis was confirmed by trephine biopsy, electron microscopy and pathomorphological study on the spleen.

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The data from the case histories of 106 patients with myocardial infarction (MI) and diabetes mellitus (DM) from the intensive care unit of III Internal Clinic of the Medical Faculty of the Higher Medical Institute "I. P. Pavlov"-- Plovdiv are interpreted as well as of the same number of patients with myocardial infarction without diabetes mellitus.

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A check up of literature has been made concerning the congenital microspherocytic hemolytic anemia, reporting of some new data about the pathogenesis of the disease. One family is described with CMHA--one father and his two daughters, the two children of his first daughter and the only child of the second daughter, hence confirming the familial character of the disease. All patients have been splenectomized.

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