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Ferenc Nagy

Publications and source records attributed to Ferenc Nagy.

At least 55 records · Page 3Linked to original sources
PubMed2004

[Surgical management of inflammatory bowel diseases].

The development of the medical management of the inflammatory bowel disease (IBD-ulcerative colitis, Crohn's disease) has reduced the number of the acute surgical interventions. Beyond the medical treatment the surgical management, the operative modalities, the pre and postoperative care has gone through a lot of changes. They review the different types of surgical alternatives and debating on the advantages and disadvantages, they put emphasis on the different surgical solutions of the Crohn's disease and that of the ulcerative colitis. Among the applied surgical alternatives to the ulcerative colitis they discuss the traditional proctocolectomy with end-ileostomy, the Kock-reservoir (as continent stoma), as well as the restorative proctocolectomy which is sufficient to preserve the anal continence. Principles of the surgery of the Crohn's disease are discussed according to the localisation of the inflammatory process (small bowel, colonic, rectal, anal channel). Because of the predisposition of relapses and the necessity of the successive surgical therapy, the extensive resections should be avoided.

Acute Disease↗
PubMed2004

Investigation of the prognostic value of TNF-alpha gene polymorphism among patients treated with infliximab, and the effects of infliximab therapy on TNF-alpha production and apoptosis.

OBJECTIVES: Infliximab, a chimeric anti-tumor necrosis factor (TNF) antibody, is highly effective for the treatment of Crohn's disease (CD) and rheumatoid arthritis (RA). Our experiments focused on RA and CD patients receiving infliximab. Since cytokine production is largely determined by genetic factors, the promoter polymorphisms of TNF-alpha were examined among these patients. Additionally, the changes caused by infliximab in the TNF-alpha-producing ability and apoptosis of peripheral blood mononuclear cells (PBMCs) were investigated. METHODS: The TNF-alpha genotypes were analyzed by PCR-RFLP. The in vitro TNF-alpha production of the PBMCs was detected by flow cytometric analysis. The TNF-alpha concentration in the supernatant was measured by bioassay. Apoptosis was detected by annexin V-fluorescein isothiocyanate labeling. RESULTS AND CONCLUSIONS: 8 of the 12 nonresponder patients carried the TNF A allele associated with high TNF-alpha production. We suggest that the determination of TNF polymorphism may help identify more suitable candidates for infliximab treatment. Although in vitro infliximab treatment for 48 h resulted in significant (44.2 +/- 1.17%) apoptosis in PBMCs, in ex vivo samples from RA patients who received infliximab, apoptosis was only 13.3 +/- 1.6%. Furthermore, infliximab did not result in irreversible inhibition of the TNF-alpha-producing ability or in the significant apoptosis of PBMCs.

Alleles↗
PubMed2003

[Effects of cardiovascular risk factors on hemorheologic parameters in cerebrovascular patients].

INTRODUCTION: Hemorheological factors are of significance in the determination of flow characteristics of blood and play an important role in the pathogenesis of cerebrovascular diseases. AIMS AND METHODS: In this study the changes of rheological factors--hematocrit (Hct), plasma fibrinogen concentration (PFC), whole blood (WBV) and plasma viscosity (PV), red blood cell aggregation (AI) and deformability and the association between these parameters and cardiovascular risk factors were investigated in 297 patients (173 males, 124 females, mean age: 60 11 years) with chronic phase (3 months after onset) ischemic cerebrovascular diseases, and in 68 healthy volunteers (30 males, 38 females, mean age: 36 6 years). RESULTS: All investigated hemorheological factors were significantly (p < 0.05-0.0001) elevated in cerebrovascular patients compared to normal controls, the rise in Hct, WBV and PV are some of the most prominent findings. In the group of hypertensive, hyperlipidemic patients, smokers and alcoholics Hct, PFC, WBV, PV and AI were significantly (p < 0.05-0.0001) higher compared to healthy controls, the same factors except plasma fibrinogen concentration showed association with diabetic history. Comparing cerebrovascular patients with or without risk factors, the most severe hemorheological deficit was observed in patients with hyperlipidemia and smoking habits. CONCLUSIONS: In this study the authors proved in chronic ischemic cerebrovascular patients that hemorheological abnormalities persist in most cases for a long time after an acute stroke, significant correlation could be seen between blood rheology and cardiovascular risk factors. Examination of rheological parameters can support to choose the optimal medical treatment in the secondary prevention of stroke, correction of hemorheological disturbances can reduce the risk of recurrent stroke.

Adult↗
PubMed2003

[Effect of vinpocetin on the hemorheologic parameters in patients with chronic cerebrovascular disease].

INTRODUCTION: Data collected from large number of multicenter, randomized trials in acute and chronic stroke patients provide evidence, that incidence and high mortality of cerebrovascular disorders can be decreased mainly by prevention and that the effectiveness of acute stroke treatment is limited. The terminology of "chronic cerebrovascular diseases" involves many pathologic entities and often atypical clinical symptoms refer to the focal or global hypoperfusion of the brain. However, hemorheological disturbances seem to be important factors of the complex pathomechanism. Vinpocetine has successfully been used in the treatment of cerebrovascular diseases, the part of the mechanism of action are the favourable rheological effects demonstrated after oral administration in more previous studies. AIMS AND METHODS: In this study the hemorheological changes after administration of small (30 mg/day) and high dose (increased to 70 mg/day) intravenous vinpocetine for 7 days in 30 patients in chronic phase of ischemic cerebrovascular disease were investigated. RESULTS: High dose parenteral vinpocetine treatment significantly (p < 0.05-0.005) decreased the hematocrit, the whole blood and plasma viscosity and red blood cell aggregation compared to the values before the treatment. Only red blood cell aggregation was improved significantly (p < 0.05) by small dose treatment. CONCLUSION: This study and other hemorheological studies in cerebrovascular patients demonstrated persistent rheological abnormalities despite the preventive therapy. The beneficial rheological effect of high dose parenteral vinpocetine indicates the use of this drug in the treatment of chronic cerebrovascular diseases.

Aged↗
PubMed2003

Light perception and signalling in higher plants.

Plants monitor changes in the ambient light environment using sensory photoreceptor families: the phototropins and cryptochromes, which absorb UV-A or blue light; the phytochromes, which sense red/far-red light; and the UV-B photoreceptors, which have not yet been identified. Recent advances suggest that photoreceptor-induced signalling cascades regulate light-modulated gene expression. These regulatory networks interact at the levels of transcription, posttranslational modification and nucleo-cytoplasmic compartmentalisation.

Cryptochromes↗
PubMed2003

Characterization of two Myb-like transcription factors binding to CAB promoters in wheat and barley.

The expression pattern and level of light-regulated genes are controlled by complex regulatory networks. Expression of genes encoding chlorophyll a/b-binding proteins of photosystem II is controlled by different photoreceptors and regulated primarily at the level of transcription. Light-dependent transcription of these genes is further modulated by the circadian system, affected by a developmental program and by a variety of environmental factors such as stress. Here we report the isolation of two Myb-like transcription factors from barley, HvMCB1 and HvMCB2, that bind specifically to defined regions of CAB promoters derived from wheat and barley. Deletion and mutation analysis of the wheat CAB1 promoter suggest that HvMCB1 and HvMCB2 are required for high-level but not for light- and circadian clock-regulated expression. Moreover, we demonstrate that the induction of HvMCB1 and HvMCB2 transcription is regulated differentially by environmental factors and plastid development. These observations indicate that HvMCB1 and HvMCB2, together with other, yet unknown regulatory factors, may mediate responsiveness of CAB gene transcription to a variety of environmental and developmental signals.

Amino Acid Sequence↗
PubMed2003

Phytochrome controlled signalling cascades in higher plants.

Plants can sense the changes in the environmental light conditions with highly specialized photoreceptors. Phytochromes are sensitive to red and far-red light and have a dual role in the life of plants. These photoreceptors play an important role in plant growth and development from germination to seed maturation and they are also involved in synchronizing the circadian clock with light/dark cycles. Biochemical, cell biological and genetic studies have been carried out to elucidate the molecular mechanism by which phytochromes transduce light signals. A major step in this process seems to be the light-dependent nuclear import of phytochromes. In the nuclei phytochromes interact with transcription factors and regulate the expression of numerous genes, resulting in complex physiological and developmental responses to light. This review focuses on the recently obtained results leading to the identification of some factors and processes involved in phytochrome signalling.

Journal Article↗
PubMed2002

[Conservative therapy of inflammatory bowel diseases].

In the past years there have been many exciting developments in IBD management. New therapies and concepts of remission induction and of maintenance have been developed. This paper is intending to bring together the basic topics in patient-management in the various medical fields that represent the most accepted ways of therapies. The introduction deals with the most common aspects of Crohn's disease and that of the ulcerative colitis. It describes the treatment of ulcerative colitis according to the different groups of patients and the degree of activity. First it analyses the possible ways leading to the remission, then the prevention of relapse, lastly the other therapeutic options which have not been given any evidence of so far. The main standards of Crohn's disease therapy are presented on the bases of the small bowel Crohn's disease. After discussing the essential principles in treating the complications it carries on the treating of the large bowel Crohn's disease and then it is completed with the consideration of prevention of the relapse and the supportive therapeutic possibilities.

Acute Disease↗
PubMed2002

[Psychiatric sequelae of interferon-alpha therapy].

INTRODUCTION: Psychopathologic conditions commonly complicate the treatment with the interferon-alpha. The most important among them is depression, which can induce suicidal attempt. The outcome of mental side effects of interferon-alpha necessitate the discontinuation of therapy and, in more severe cases, psychiatric treatment. AIM AND METHOD: A brief literature review presents the biology of interferon-alpha with emphasis on the central nervous system effects which are probably closely related to mental side effects. Three case reports demonstrate the interdisciplinary nature of interferon induced psychiatric conditions. RESULTS: The appearance of neuropsychiatric side effects of interferon-alpha are frequent, the consequences of which can prove dramatic: involvement of the vital prognosis, psychiatric morbidity, especially depressions, and suicidal risk. CONCLUSION: The close collaboration of clinical practitioners and psychiatrists, from the pre-therapeutical evaluation to the follow up care is required.

Anxiety↗
PubMed2002

[Volumetric measurements of the hippocampus and amygdala with MRI in healthy adults].

INTRODUCTION: Volumetric analysis of brain magnetic resonance images (MRI) measures structural changes associated with neurological and neuropsychiatric disorders. In recent years several studies have shown the utility of the volumetric measurement of the medial temporal lobe structures, especially the amygdala and the hippocampus in temporal lobe epilepsy, memory disorders, Alzheimer disease and schizophrenia. AIM: The purpose of this study was to measure and establish our normal values of the hippocampus and amygdala volumes. METHODS: All studies were performed using a 1.0 T Siemens unit with FISP 3D sequence. One millimeter, contiguous coronal scans of 40 healthy volunteers aged 19-26 years were obtained. The regions of interest were outlined using a mouse driven cursor. To determine the anatomic boundaries of the hippocampus and the amygdala the authors followed a generally accepted protocol previously described by C. Watson. RESULTS: The mean right and left hippocampal volumes were 2.12 cm3 (SD = 0.31) and 2.07 cm3 (SD = 0.3) and the mean right and left amygdaloid volume were 1.19 cm3 (SD = 0.19) and 1.2 cm3 (SD = 0.2) respectively. The mean asymmetry between the right and left hippocampus and amygdala was 3.17% and 3.48%, respectively. The inter-observer reliability range (alpha) was between 0.97 and 0.77. Subregional analysis of hippocampus was calculated as well. CONCLUSIONS: Normal volumetric data measured in our study fell in the midrange of the values in the literature. The volumetric analysis of the hippocampal subregions may allow assessment of providing more sensitive determination of the atrophic area, which may be important in epileptic disorders.

Adult↗
PubMed2002

The ELF4 gene controls circadian rhythms and flowering time in Arabidopsis thaliana.

Many plants use day length as an environmental cue to ensure proper timing of the switch from vegetative to reproductive growth. Day-length sensing involves an interaction between the relative length of day and night, and endogenous rhythms that are controlled by the plant circadian clock. Thus, plants with defects in circadian regulation cannot properly regulate the timing of the floral transition. Here we describe the gene EARLY FLOWERING 4 (ELF4), which is involved in photoperiod perception and circadian regulation. ELF4 promotes clock accuracy and is required for sustained rhythms in the absence of daily light/dark cycles. elf4 mutants show attenuated expression of CIRCADIAN CLOCK ASSOCIATED 1 (CCA1), a gene that is thought to function as a central oscillator component. In addition, elf4 plants transiently show output rhythms with highly variable period lengths before becoming arrhythmic. Mutations in elf4 result in early flowering in non-inductive photoperiods, which is probably caused by elevated amounts of CONSTANS (CO), a gene that promotes floral induction.

Arabidopsis↗
PubMed2002

[Subtotal colectomy for the treatment of obstructive left colon cancer. Follow-up results].

AIM: Subtotal colectomy (STC) involves an extended resection of the large bowel over the splenic flexure. In a period of 8 years, a total of 72 subtotal colectomies (STC) were performed for the treatment of large bowel obstructions or symptomatic stenosis caused by cancer of the left colon. A primary ileocolic latero-terminal anastomosis was made in each case. The aim of study was to evaluate the late results of procedure. PATIENTS AND METHODS: In a non-prospective, non-randomized study of 23 of the total of 72 STC cases, authors investigated the postoperative quality of life, the changes in the intestinal bacterial flora, and signs of a nutritional deficiency or of an accelerated bowel transit. METHODS: 1) H2 excretion test, 2) UDCA-PABA and 3) Schilling test for contaminated small bowel syndrome and bowel transit time, studied by means of a 4) barium meal and 5) radiopaque marker passage, and 6) registration of the number of defecations/day. RESULTS: The laboratory findings were in the normal range in each case. The daily number of defecations gradually decreased during the 3 months after the operation (mean 1.9/day). The lack of an ileocoecal valve did not result in bacterial overgrowth in the small bowel and the investigations did not reveal contaminated bowel syndrome. The oro-anal transit time was reduced in only four cases. Three months postoperatively, no patient had a deteriorated quality of life. CONCLUSIONS: STC offers 1) one-stage treatment for colonic obstruction in emergency surgery, 2) tumour removal with sufficient oncological radicality, and 3) primary reconstruction of the digestive tract, with a safe ileocolic anastomosis even in emergency cases. The follow-up study of 23 of the patients proved that loss of 60-80% of the colon did not cause any symptomatic disturbance of the digestive functions. The quality of life after surgery was normal, the slightly increased number (mean 1.9) of daily defecations was acceptable, and bacterial colonization of the small bowel did not occur.

Aged↗
PubMed2002

Characterisation of BRH1, a brassinosteroid-responsive RING-H2 gene from Arabidopsis thaliana.

Although many important aspects of plant development are controlled by brassinosteroids (BRs), the early molecular events of their hormonal action are largely unknown. Using a differential-display RT-PCR screen designed to detect early response transcripts, those regulated by BR treatment in the absence of de novo protein synthesis, we identified an Arabidopsis thaliana (L.) Heynh. gene (designated BRH1) that encodes a novel RING finger protein. As deduced from a complete cDNA clone, the 170-amino-acid sequence of BRH1 forms an N-terminal hydrophobic domain and a C-terminal RING-H2 signature. In wild-type Arabidopsis, the level of the BRH1 transcript was rapidly down-regulated by brassinolide, but this effect was abolished in a BR-insensitive mutant deficient in the BRI1 receptor. BRH1 mRNA abundance was not influenced by other phytohormones, but the pathogen elicitor chitin induced a rapid and transient accumulation of the transcript. Antisense expression of BRH1 resulted in transgenic Arabidopsis plants with thicker inflorescence stems and altered leaf morphology, whereas in sense overexpression lines no phenotypic effect could be observed. Considering the potential of the RING proteins to participate in regulatory protein complexes, BR-dependent expression of BRH1 may suggest its involvement in later hormonal effects.

Amino Acid Sequence↗
PubMed2002

Plant RanGAPs are localized at the nuclear envelope in interphase and associated with microtubules in mitotic cells.

In animals and yeast, the small GTP-binding protein Ran has multiple functions - it is involved in mediating (i) the directional passage of proteins and RNA through the nuclear pores in interphase cells; and (ii) the formation of spindle asters, the polymerization of microtubules, and the re-assembly of the nuclear envelope in mitotic cells. Nucleotide binding of Ran is modulated by a series of accessory proteins. For instance, the hydrolysis of RanGTP requires stimulation by the RanGTPase protein RanGAP. Here we report the complementation of the yeast RanGAP mutant rna1 with Medicago sativa and Arabidopsis thaliana cDNAs encoding RanGAP-like proteins. Confocal laser microscopy of Arabidopsis plants overexpressing chimeric constructs of GFP with AtRanGAP1 and 2 demonstrated that the fusion protein is localized to patchy areas at the nuclear envelope of interphase cells. In contrast, the cellular distribution of RanGAPs in synchronized tobacco cells undergoing mitosis is characteristically different. Double-immunofluorescence shows that RanGAPs are co-localized with spindle microtubules during anaphase, with the microtubular phragmoplast and the surface of the daughter nuclei during telophase. Co-assembly of RanGAPs with tubulin correlates with these in vivo observations. The detected localization pattern is consistent with the postulated function of plant RanGAPs in the regulation of nuclear transport during interphase, and suggests a role for these proteins in the organization of the microtubular mitotic structures.

Active Transport, Cell Nucleus↗
PubMed2002

Distinct regulation of CAB and PHYB gene expression by similar circadian clocks.

Phytochrome B (phyB) is a major phytochrome active in light-grown plants. The circadian clock controls the expression of the PHYB gene. We have used the luciferase reporter gene (LUC) to monitor the rhythmic expression of PHYB in photoreceptor and clock-associated mutant backgrounds. Surprisingly, we found that PHYB and CAB expression have different free-running periods, indicating that separate circadian clocks control these genes. The effects of mutations show that the clocks share common components. This suggests that they are copies of the same clock mechanism in different locations, most likely in different cell layers. Furthermore, we show that phyB is required for a negative feedback loop that strongly antagonises the expression of PHYB. Compared to a system with only one clock, this regulatory complexity might allow the phase of peak expression for one clock-controlled gene to alter, relative to other genes or to changing environmental conditions.

Arabidopsis↗
PubMed2002

Regulation of transcript levels of the Arabidopsis cytochrome p450 genes involved in brassinosteroid biosynthesis.

Cytochrome P450 enzymes of the closely related CYP90 and CYP85 families catalyze essential oxidative reactions in the biosynthesis of brassinosteroid (BR) hormones. Arabidopsis CYP90B1/DWF4 and CYP90A1/CPD are responsible for respective C-22 and C-23 hydroxylation of the steroid side chain and CYP85A1 catalyzes C-6 oxidation of 6-deoxo intermediates, whereas the functions of CYP90C1/ROT3, CYP90D1, and CYP85A2 are still unknown. Semiquantitative reverse transcriptase-polymerase chain reaction analyses show that transcript levels of CYP85 and CYP90 genes are down-regulated by brassinolide, the end product of the BR biosynthesis pathway. Feedback control of the CYP90C1, CYP90D1, and CYP85A2 genes by brassinolide suggests that the corresponding enzymes might also participate in BR synthesis. CYP85 and CYP90 mRNAs show strong and transient accumulation during the 1st week of seedling development, as well as characteristic organ-specific distribution. Transcripts of CYP90A1 and CYP85A2 are preferentially represented in shoots and CYP90C1, CYP90D1, and CYP85A1 mRNAs are more abundant in roots, whereas CYP90B1 is ubiquitously expressed. Remarkably, the spatial pattern of CYP90A1 expression is maintained in the BR-insensitive cbb2 mutant, indicating the independence of organ-specific and BR-dependent regulation. Quantitative gas chromatography-mass spectrometry analysis of endogenous BRs in shoots and roots of Arabidopsis, pea (Pisum sativum), and tomato (Lycopersicon esculentum) reveal similar partitioning patterns of BR intermediates in these species. Inverse correlation between CYP90A1/CPD transcript levels and the amounts of the CYP90A1 substrate 6-deoxocathasterone in shoots and roots suggests that transcriptional regulation plays an important role in controlling BR biosynthesis.

Arabidopsis↗