226 results on '"Chatzopoulos, Dimitrios"'
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202. Ofeleein i mi Vlaptin -Volume II: Immunity Following Infection or mRNA Vaccination, Drug Therapies and Non-Pharmacological Management at Post-Two Years SARS-CoV-2 Pandemic.
- Author
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Kountouras J, Gialamprinou D, Kotronis G, Papaefthymiou A, Economidou E, Soteriades ES, Vardaka E, Chatzopoulos D, Tzitiridou-Chatzopoulou M, Papazoglou DD, and Doulberis M
- Subjects
- Humans, Pandemics, RNA, Messenger, Vaccination, COVID-19, SARS-CoV-2
- Abstract
The persistence of the coronavirus disease 2019 (COVID-19) pandemic has triggered research into limiting transmission, morbidity and mortality, thus warranting a comprehensive approach to guide balanced healthcare policies with respect to people's physical and mental health. The mainstay priority during COVID-19 is to achieve widespread immunity, which could be established through natural contact or vaccination. Deep knowledge of the immune response combined with recent specific data indicates the potential inferiority of induced immunity against infection. Moreover, the prevention of transmission has been founded on general non-pharmacological measures of protection, albeit debate exists considering their efficacy and, among other issues, their socio-psychological burden. The second line of defense is engaged after infection and is supported by a plethora of studied agents, such as antibiotics, steroids and non-steroid anti-inflammatory drugs, antiviral medications and other biological agents that have been proposed, though variability in terms of benefits and adverse events has not allowed distinct solutions, albeit certain treatments might have a role in prevention and/or treatment of the disease. This narrative review summarizes the existing literature on the advantages and weaknesses of current COVID-19 management measures, thus underlining the necessity of acting based on the classical principle of " ofeleein i mi vlaptin ", that is, to help or not to harm.
- Published
- 2022
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203. Helicobacter pylori infection might contribute to esophageal adenocarcinoma progress in subpopulations with gastroesophageal reflux disease and Barrett's esophagus.
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Kountouras J, Chatzopoulos D, Zavos C, Polyzos SA, Giartza-Taxidou E, Vardaka E, Molyvas E, Kouklakis G, Tsiaousi E, and Klonizakis P
- Subjects
- Humans, Barrett Esophagus microbiology, Esophageal Diseases microbiology, Helicobacter Infections microbiology, Helicobacter pylori physiology
- Published
- 2012
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204. Potential implications of Helicobacter pylori-related neutrophil-activating protein.
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Kountouras J, Zavos C, Deretzi G, Gavalas E, Chatzopoulos D, Katsinelos P, Tsiaousi E, Gagalis S, Polyzos SA, and Venizelos I
- Subjects
- Humans, Anti-Bacterial Agents therapeutic use, Bacterial Proteins metabolism, Helicobacter Infections drug therapy, Helicobacter pylori metabolism, Inflammation drug therapy, Resins, Plant therapeutic use
- Abstract
Helicobacter pylori (H. pylori) virulence factors promote the release of various chemoattractants/inflammatory mediators, including mainly the neutrophil-attractant chemokine interleukin-8 and neutrophil-activating protein (NAP), involved in H. pylori-induced gastric pathologies. Co-administration of Chios mastic gum (CMG), which inhibits H. pylori NAP, with an H. pylori eradication regimen might add clinical benefits against H. pylori-related gastric pathologies, but possibly not CMG as main therapy. Although H. pylori NAP and other H. pylori-related cytotoxins [i.e., vaculating cytotoxin (VacA)] appear to play a major role in generating and maintaining the H. pylori-associated gastric inflammatory response and H. pylori NAP is a promising vaccine candidate against H. pylori infection (H. pylori-I), concerns regarding its potential drawbacks, particularly neurogenic ones, due to possible cross-mimicry, should be considered. Possible cross-mimicry between H. pylori NAP and/or bacterial aquaporin (AQP) and neural tissues may be associated with the anti-AQP-4 antibody-related neural damage in multiple sclerosis (MS)/neuromyelitis optica patients. Moreover, the sequence homology found between H. pylori VacA and human Na+/K+-ATPase A subunit suggests that antibodies to VacA involve ion channels in abaxonal Schwann cell plasmalemma resulting in demyelination in some patients. A series of factors have been implicated in inducing blood-brain barrier (BBB) disruption, including inflammatory mediators (e.g., cytokines and chemokines induced by H. pylori-I) and oxidative stress. BBB disruption permits access of AQP4-specific antibodies and T lymphocytes to the central nervous system, thereby playing a major role in multiple sclerosis pathogenesis. Relative studies show a strong association between H. pylori-I and MS. H. pylori-I induces humoral and cellular immune responses that, owing to the sharing of homologous epitopes (molecular mimicry), cross-react with components of nerves, thereby contributing and perpetuating neural tissue damage. Finally, H. pylori NAP also plays a possible pathogenetic role in both gastric and colon oncogenesis.
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- 2012
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205. Yttrium-90 radiation synovectomy in knee osteoarthritis: a prospective assessment at 6 and 12 months.
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Chatzopoulos D, Moralidis E, Markou P, and Makris V
- Subjects
- Aged, Female, Follow-Up Studies, Humans, Male, Osteoarthritis, Knee therapy, Safety, Time Factors, Treatment Outcome, Osteoarthritis, Knee surgery, Radiosurgery adverse effects, Synovectomy, Yttrium Radioisotopes therapeutic use
- Abstract
Objective: To assess the outcome of yttrium-90 radiation synovectomy at 6 and 12 months in patients with knee osteoarthritis unresponsive to systematic or local medical treatment., Methods: Consecutive patients with osteoarthritic knee pain resistant to conventional therapy and submitted to intraarticular yttrium-90 treatment because of synovial inflammation, as demonstrated by early-phase bone scintigraphy, were prospectively evaluated at 6 and/or 12 months. The assessment of the outcome of treatment was based on self-reporting of relief of knee pain limiting daily activities, measured as percentage reduction of the pretherapeutic joint discomfort with a Visual Analogue Scale. Resting and nocturnal pain also were considered, together with knee flexibility and ultrasonographic changes., Results: Among a total of 97 patients, a > or =50% Visual Analogue Scale pain palliation was experienced by 64 of 90 (71.1%) patients at 6 months and 50 of 69 (72.5%) at 12 months (P = 0.992). Moreover, nocturnal and resting pain alleviation, gain in knee flexibility and regression of large joint effusions and Baker's cysts were observed in considerable proportions. In the evaluation of the outcome of treatment in 62 patients with serial assessments using a composite criterion, 42 (67.7%) versus 40 (64.5%) had a satisfactory response at 6 and 12 months, respectively (P = 0.850). The probability of a favourable therapeutic result was inversely related to the severity of radiographic joint changes., Conclusion: Yttrium-90 synovectomy exerts a beneficial therapeutic effect in a substantial proportion of patients with osteoarthritic knee pain and synovial inflammation, inadequately controlled by pharmacotherapy. Clinical improvement is inversely related to radiographic knee damage.
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- 2009
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206. Yttrium-90 silicate radiosynovectomy treatment of painful synovitis in knee osteoarthritis. Results after 6 months.
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Markou P and Chatzopoulos D
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- Aged, Aged, 80 and over, Arthralgia etiology, Female, Humans, Male, Middle Aged, Osteoarthritis, Knee complications, Radiopharmaceuticals, Treatment Outcome, Arthralgia diagnosis, Arthralgia prevention & control, Osteoarthritis, Knee diagnosis, Osteoarthritis, Knee radiotherapy, Silicates therapeutic use, Yttrium therapeutic use
- Abstract
Our aim was to evaluate the response of radiation synovectomy (RS) with yttrium-90 silicate ((90)Y-S) treatment of synovitis in patients with knee osteoarthritis (OA) and to derive factors that influence this response. The RS treatment response was assessed prospectively in 74 painful OA knees of 74 patients during a period of 6 months follow up. The duration of the disease was 24 +/- 9 months. Forty-four of the 74 knees had pain during the night and 43/74 had abnormal flexibility. Knee joints were graded according to the Steinbrocker radiological system. RS was performed according to the European Association of Nuclear Medicine guidelines. RS response was assessed considering the pain improvement from baseline values in terms of a 100-point visual analogue scale (VAS), the improvement of knee flexibility and the pain remission during the night. RS response was classified as poor (VAS<25), fair (VAS>or=25-50), good (VAS >or=50-75) and excellent (VAS>or=75), with excellent and good results considered as success, while fair and poor as failure. Our results show that 6 months after RS treatment, the percentage of VAS from baseline values was 66.0% +/- 24.8% and found to be significantly related to patients' age (P=0.01), duration of the disease (P=0.04) and to radiographic grading of OA (P=0.001). Knees without or with mineral type OA radiographic changes (Steinbrocker's grades 0-I) responded better than those with more advanced changes (Steinbrocker's grade III-IV) in terms of VAS improvement (77.9% versus 53.8%) (P < 0.001). The overall success rate (VAS >or= 50) was 83.8%. Remission of pain during the night was achieved in 88.6% and knee flexibility was improved in 65.1%. RS side effects assessed for the whole follow-up period were minor and not significant. In conclusion, RS with a single injection of (90)Y-S in patients with knee OA seems to have a significant therapeutic effect after a six months follow-up period with no significant side effects. Six months after RS treatment, clinical improvement was inversely related to radiographic knee damage, patients" age and duration of the disease. RS also induced remission of OA pain during the night.
- Published
- 2009
207. Baker's cysts in knees with chronic osteoarthritic pain: a clinical, ultrasonographic, radiographic and scintigraphic evaluation.
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Chatzopoulos D, Moralidis E, Markou P, Makris V, and Arsos G
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- Aged, Aged, 80 and over, Comorbidity, Female, Greece epidemiology, Humans, Knee Joint diagnostic imaging, Male, Middle Aged, Osteoarthritis, Knee complications, Osteoarthritis, Knee epidemiology, Pain etiology, Popliteal Cyst epidemiology, Popliteal Cyst etiology, Prevalence, Radiography, Synovitis complications, Synovitis pathology, Tomography, Emission-Computed, Ultrasonography, Osteoarthritis, Knee pathology, Pain pathology, Popliteal Cyst diagnosis
- Abstract
This study aimed to determine the ultrasonographic prevalence of Baker's cysts in knees with chronic osteoarthritic pain and investigate for cysts correlates and relationships with scintigraphically established synovitis. Consecutive patients with chronic osteoarthritic knee pain underwent clinical examination, X-rays, ultrasonography and early-phase bone scintigraphy. Eighty-nine Baker's cysts were detected in 328 knees with chronic osteoarthritic pain (27%), whereas one cyst was identified among the 54 non-osteoarthritic knees (2%, P<0.001). Baker's cysts were detected in 72/195 (37%) patients with knee osteoarthritis. Abnormal and intense tracer accumulation in early-phase bone scintigraphy were significantly more frequent in osteoarthritic knees with Baker's cysts (97 and 56%, respectively), than in those without (89 and 40%, respectively, P<0.05 for both). Clinical and radiographic variables could not predict the presence of those cysts. Baker's cysts are a common ultrasonographic finding in knees with chronic osteoarthritic pain and are associated with synovial inflammation and its grade.
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- 2008
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208. Validity study of the Moral Judgment Test in Physical Education: development and preliminary validation.
- Author
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Chatzopoulos D, Mouratidou K, and Karamavrou S
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- Adolescent, Attitude, Child, Female, Humans, Male, Models, Psychological, Psychometrics, Reproducibility of Results, Sports psychology, Teaching, Judgment, Moral Development, Morals, Physical Education and Training statistics & numerical data, Students psychology, Surveys and Questionnaires
- Abstract
Teaching ethical behavior is an aspect of physical education. The purpose of the study was to present the construction and to estimate validity of a test which assesses physical education students' moral judgment, the Moral Judgment Test in Physical Education. The sample comprised 281 male and female participants (95 in Grades 7 to 9, 92 in Grades 10 to 12, and 94 university students), who completed Lind's Moral Judgment Test and the Moral Judgment Test-PE version. The validity of the latter was assessed using four criteria of Lind's moral theory. Analysis indicated that the Moral Judgment Test-PE had adequate construct validity and correlated positively, although relatively weakly, with the original test, so the new version has sufficient construct validity to be used in physical education.
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- 2008
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209. Efficacy and safety of infliximab in steroid-dependent ulcerative colitis patients.
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Gavalas E, Kountouras J, Stergiopoulos C, Zavos C, Gisakis D, Nikolaidis N, Giouleme O, Chatzopoulos D, and Kapetanakis N
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- Adolescent, Adult, Aged, Anti-Inflammatory Agents adverse effects, Antibodies, Monoclonal adverse effects, Female, Glucocorticoids therapeutic use, Humans, Infliximab, Male, Middle Aged, Anti-Inflammatory Agents therapeutic use, Antibodies, Monoclonal therapeutic use, Colitis, Ulcerative drug therapy
- Abstract
Background/aims: Limited data exist concerning infliximab administration in steroid-dependent ulcerative colitis (UC) patients. The aim of this study was to evaluate the efficacy and safety of infliximab in steroid-dependent disease., Methodology: Sixteen corticosteroid-dependent patients who received infusions of infliximab (5 mg/kg) at 0, 2 and 6 weeks and thereafter every 8 weeks (Group A), were compared with eight patients treated with methylprednisolone (0.8-1 mg/kg body weight) daily for three weeks followed by a tapering regimen up to the minimal dose to maintain a symptom-free condition (Group B). Steroid dependency was defined as recurrent flare-up on steroid reduction or withdrawal, or as the clinical need for steroid treatment twice within six consecutive months or three times within a year. Disease activity was assessed at recruitment, and clinical response was evaluated according to the two non-invasive indices [SEO and Simple Clinical Colitis Activity Index (SCCAI) scores]., Results: In Group A, complete long-term response occurred in 68.75% and partial response in 18.75% of patients. Moreover, in the long-term follow-up, both SCCAI (10.37 +/- 2.27 vs. 3.31 +/- 2.65, p < 0.001) and SEO (209.33 +/- 13.6 vs. 123.3 +/- 34.8, p < 0.001) scores demonstrated a significant improvement. In group B, comparable features were also obtained regarding complete long-term (62.5%) and partial (25%) responses; both SCCAI (7.37 +/- 1.4 vs. 3.5 +/- 3.58, p = 0.039) and SEO (181.0 +/- 27.1 vs. 135.3 +/- 44.1, p = 0.038) scores also improved significantly. Six of eight patients in the methylprednisolone-treated group B developed Cushing-like symptoms., Conclusions: Infliximab appears to be a good alternative therapeutic regimen in steroid-dependent UC patients associated with long-term potential toxicity.
- Published
- 2007
210. Bax upregulation may provide a rationale for the low incidence of esophageal adenocarcinoma in a Greek cohort of patients with Barrett's esophagus.
- Author
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Chatzopoulos D, Kyrgidis A, Kountouras J, Zavos C, Molyvas E, and Venizelos I
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- Adenocarcinoma pathology, Adult, Apoptosis, Barrett Esophagus pathology, Cell Proliferation, Cohort Studies, Esophageal Neoplasms pathology, Esophagus chemistry, Esophagus pathology, Female, Gastroesophageal Reflux diagnosis, Gastroesophageal Reflux pathology, Greece, Humans, Incidence, Ki-67 Antigen analysis, Ki-67 Antigen metabolism, Male, Middle Aged, Proto-Oncogene Proteins c-bcl-2 analysis, Proto-Oncogene Proteins c-bcl-2 metabolism, Up-Regulation, bcl-2-Associated X Protein analysis, Adenocarcinoma epidemiology, Barrett Esophagus complications, Esophageal Neoplasms epidemiology, bcl-2-Associated X Protein metabolism
- Abstract
Background/aims: Previously rare, esophageal adenocarcinoma (EA) is now the most common esophageal malignancy in Western countries whose incidence is increasing faster than any other cancer. However, mortality from esophageal cancer in Greece is among the lowest in the world and no clear-cut answer has emerged as to why the incidence of EA is so low in this country. Thus, the aim of the study was to provide an explanation for the low incidence of EA in Greece through molecular-based ethnic differentiations., Methodology: Out of 270 patients who underwent upper gastrointestinal endoscopic and histologic evaluation due to GERD symptoms, 31 patients (23 males, 8 females, mean age 47.10 +/- 11.88 years) with BE (typical salmon-pink lesions) and 21 GERD controls (12 males, 9 females, mean age 46.57 +/- 17.71 years) were ultimately included in the study. Esophageal mucosa biopsy specimens were evaluated immunohistochemically for Ki-67, Bax and Bcl-2 expressions., Results: Increased expression of Ki-67 was observed in BE patients compared with GERD controls (p = 0.01); increased expression of Bax was noticed in the total BE patients compared with GERD controls (p < 0.001); Bcl-2 expression did not differ between the two groups., Conclusions: Our findings indicate a possible existence of a balance between cell proliferation (indicated by Ki-67 increased expression) and apoptosis (indicated by Bax protein overexpression), thereby providing an equilibrium between cell apoptosis and cell proliferation, and this may partly explain the low EA incidence in Greece.
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- 2007
211. Molecular mechanisms associated with aggressiveness of alpha-fetoprotein-positive gastric cancer.
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Kountouras J, Zavos C, Chatzopoulos D, and Katsinelos P
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- Animals, Cell Transformation, Neoplastic genetics, Cell Transformation, Neoplastic pathology, Gastric Mucosa pathology, Helicobacter Infections genetics, Helicobacter Infections pathology, Helicobacter pylori genetics, Humans, Liver Neoplasms pathology, Lymphatic Metastasis genetics, Lymphatic Metastasis pathology, Neoplasm Invasiveness pathology, Neoplastic Cells, Circulating, Tumor Suppressor Protein p53 genetics, Liver Neoplasms genetics, Liver Neoplasms secondary, Neoplasm Invasiveness genetics, Stomach Neoplasms genetics, alpha-Fetoproteins genetics
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- 2007
212. The role of gastric Helicobacter pylori infection in laryngopharyngeal reflux disease.
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Kountouras J, Zavos C, and Chatzopoulos D
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- Gastric Mucosa microbiology, Gastroesophageal Reflux microbiology, Humans, Gastroesophageal Reflux physiopathology, Helicobacter Infections physiopathology, Helicobacter pylori, Hypopharynx, Pharyngeal Diseases microbiology, Pharyngeal Diseases physiopathology
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- 2007
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213. Alzheimer's disease and Helicobacter pylori infection: Defective immune regulation and apoptosis as proposed common links.
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Kountouras J, Gavalas E, Zavos C, Stergiopoulos C, Chatzopoulos D, Kapetanakis N, and Gisakis D
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- Alzheimer Disease immunology, Alzheimer Disease microbiology, Antibodies, Bacterial analysis, Apoptosis, Helicobacter Infections immunology, Humans, Immunoglobulin G analysis, Alzheimer Disease etiology, Helicobacter Infections complications, Helicobacter pylori
- Abstract
Although degenerative diseases of the central nervous system, including Alzheimer's disease (AD), have an increasingly high impact on aged population their association with Helicobacter pylori (H. pylori) infection has not as yet been thoroughly researched. Current H. pylori infection appears to induce irregular humoral and cellular immune responses that, owing to the sharing of homologous epitopes (molecular mimicry), cross-react with components of nerves, thereby contributing and possibly perpetuating the apoptotic neural tissue damage observed in neurodegenerative diseases including AD. An association between AD and H. pylori infection has been recently addressed by two studies. A higher seropositivity for anti-H. pylori immunoglobulin G antibodies in 30 patients with AD than in 30 age-matched controls was reported in one study; this serological test, however, has limitations because it does not discriminate between current and old infections. In the other study, by introducing the histological method (the actual gold standard) for diagnosis of H. pylori infection, we reported a higher prevalence of H. pylori infection in 50 AD patients than in 30 anemic controls. This pathogen may influence the pathophysiology of AD by promoting platelet and platelet-leukocyte aggregation; releasing various pro-inflammatory and vasoactive substances; developing cross-mimicry with host antigens; producing reactive oxygen metabolites and circulating lipid peroxides; influencing the apoptotic process; and increasing, through induction of atrophic gastritis, homocysteine, which contributes to vascular disorders implicated in endothelial damage and neurodegeneration.
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- 2007
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214. [Radiation doses from patients undergoing yttrium-90 silicate knee radiosynovectomy].
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Badiavas K, Chatzopoulos D, and Markou P
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- Body Burden, Greece, Humans, Medical Staff, Hospital, Radiation Dosage, Relative Biological Effectiveness, Risk Assessment methods, Risk Factors, Knee Joint, Occupational Exposure analysis, Radiation Protection methods, Synovitis radiotherapy, Whole-Body Counting methods, Yttrium Radioisotopes analysis, Yttrium Radioisotopes therapeutic use
- Abstract
The present study was undertaken because we could not find references related to the minimal radiation doses emitted from patients treated with (90)Y-silicate colloid ((90)Y-SC) for radiosynectomy (RS). Radiation doses from 16 patients treated with about 181+/-13 MBq (90)Y-SC for RS of knee synovitis were estimated by dose rate measurements performed within 10 min after the (90)Y-SC injection with a calibrated survey dose ratemeter at 0.5 m, 1 m and 2 m distances from the treated joint. The mean dose rate values from the patients after bg subtraction were 0.6+/-0.4 microSv/h at 0.5 m, 0.1+/-0.1 microSv/h at 1 m and 0.1 +/- 0.0 microSv/h at 2 m distance. Dose rates at a distance of 0.5 m were significantly correlated (P<0.02) with the patient's weight but not with the height or the injected activity. The assumed estimated maximum whole body doses from a treated patient were 55 microSv for persons living with the patient, 2.9-3.4 microSv for the nursing staff, 0.2-1.8 microSv for the therapist physician and 0.3-0.6 microSv for the technologist, involved in the whole procedure. The above values were lower than those published with the same methodology for alternative RS radiopharmaceuticals for knee synovitis like dysprosium-165 ferric hydroxide macroaggregate ((165)Dy-FHMA) or holmium-166 ((166)Ho-FHMA), as estimated with their typical injected activities. In conclusion our results demonstrate that in (90)Y-SC knee synovectomy, the whole body radiation doses to medical and non medical personnel were as expected well below the maximum annual dose limits for the public and professionals exposed to radiation.
- Published
- 2006
215. [Scintigraphic imaging of knee synovitis in osteoarthritis after intra-articular injection of technetium-99m pertechnetate in the unilateral knee].
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Chatzopoulos D, Markou P, and Iakovou I
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- Aged, Humans, Injections, Intra-Articular, Osteoarthritis, Knee complications, Radionuclide Imaging, Radiopharmaceuticals administration & dosage, Synovitis etiology, Knee Joint diagnostic imaging, Osteoarthritis, Knee diagnostic imaging, Synovitis diagnostic imaging, Technetium Tc 99m Medronate administration & dosage
- Abstract
A case of left knee synovitis scintigraphic imaging is presented in a 66-year-old patient with bilateral knee osteoarthritis and a right knee Baker's cyst, who had undergone a 74 MBq (99m)Tc-pertechnetate intra-articular injection in the right knee. The findings in this case were compared with the intravenously injected methylene disphosphonate technetium-99m ((99m)Tc-MDP) scintigraphic findings and could be interpreted as the result of (99m)Tc-pertechenate through blood communication from the right to the left knee. This case implies that (99m)Tc-pertechnetate may be useful in imaging the synovitis in multiple arthroses even up to 60 min after its administration, instead of the 5 min imaging after the injection of (99m)Tc-MDP.
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- 2006
216. New concepts of molecular biology on gastric carcinogenesis.
- Author
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Kountouras J, Zavos C, and Chatzopoulos D
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- Cell Transformation, Neoplastic genetics, Genes, Tumor Suppressor physiology, Humans, Oncogenes genetics, Mutation genetics, Stomach Neoplasms genetics
- Abstract
Gastric cancer not located in the cardia still remains the second most common cancer worldwide, whereas adenocarcinoma of the cardia and gastroesophageal junction has been rapidly rising over the past two decades. Gastric cancer can be subdivided into two distinct pathologic entities, diffuse and intestinal, that have different epidemiologic and prognostic features. Various genetic and environmental factors play important roles in gastric carcinogenesis; both lead to either abnormal genes overexpression or inappropriate expression of normal genes, whose products confer the malignant phenotype. Advances have been made in the genetic changes mostly of the intestinal type; its development is probably a multistep process, as has been well described in colon cancer pathogenesis, whereas it remains tentative whether the diffuse type of malignancy follows an analogous progression. The most common genetic abnormalities in gastric cancer tend to be loss of heterozygosity of tumor suppressor genes, particularly of p53 or "Adenomatous Polyposis Coli" gene. The latter leads to gastric oncogenesis through changes related to E-cadherin-catenin complex, which plays a critical role in the maintenance of normal tissue architecture. Mutation of any of its components results in loss of cell-cell adhesion, thereby contributing to neoplasia. E-cadherin/CDH1 gene germline mutations have been recognized in families with an inherited predisposition to gastric cancer of the diffuse type. Amplification and/or overexpression of putative trophic factors have also been observed in gastric cancer. Finally, Helicobacter pylori (H. pylori) infection is also involved in gastric carcinogenesis through various mechanisms, thereby necessitating H. pylori eradication in patients with gastric cancer.
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- 2005
217. Re: "Prognostic significance of Bcl-xL in human hepatocellular carcinoma".
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Kountouras J, Zavos C, and Chatzopoulos D
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- Humans, Prognosis, bcl-X Protein, Carcinoma, Hepatocellular metabolism, Liver Neoplasms metabolism, Proto-Oncogene Proteins c-bcl-2 metabolism
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- 2005
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218. Isolation period prediction in patients with differentiated thyroid carcinoma treated after thyroidectomy by radioiodine-131.
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Markou P and Chatzopoulos D
- Abstract
In patients with differentiated thyroid carcinoma (DTC) who after thyroidectomy underwent radioiodine-131 ((131)I) treatment for the ablation of the thyroid remnant, isolation period is considered as the period of time needed for patients' radiation dose rates to be reduced below specific adopted dose rate release limits. The aim of our study was to determine mathematical equations for the prediction of the isolation period in these patients and of their discharge from special isolation rooms in nuclear medicine departments. In order, to predict the duration of the isolation period, we studied twenty-eight patients with DTC and total thyroidectomy having no metastases, who underwent (131)I ablation treatment for a minimal residual thyroid remnant. The administered (131)I activity was 5.22 +/- 0.68 GBq, ranging from 3.66 to 6.21 GBq. Dose rates, as mean +/- SD, at a distance of 1 m from the patients were 277 +/- 44 microSv/h, immediately after (131)I administration, 72 +/- 18 microSv/h at 24 h and 23 +/- 9 microSv/h at 48 h. Whole body (131)I retention was 0.261 +/- 0.05 (range 0.168-0.385) at 24 h and 0.082 +/- 0.03 (range 0.041-0.149) at 48 h, calculated as the ratio of dose rate at 24 h and 48 h versus the initial dose rate after (131)I administration. Isolation period was calculated by a mono-exponential fitting in dose rate decay data according specific dose rate release limits. For a dose rate release limit of 30 microSv/h at 1 m, isolation period was 42.7+/-7.2 h (range 31.2-56.6 h). Seventy-five percent of the patients satisfied this limit within 48 h and 25% between 48 h and 72 h. This isolation period was positively correlated with the whole body (131)I retention and the dose rates at 24 h and 48 h, but not always with the administered activity or the initial dose rate, measured immediately after (131)I administration. On the contrary, a strong negative correlation was found between patients' isolation period and dose rate release limits between 3 and 60 microSv/h at 1 m. This study indicates that isolation period is variable but can be predicted by multiple formulas, since it depends strongly on the adopted dose rate release limits, (131)I dose rates and whole body retention at 24 h and 48 h after (131)I treatment. For a dose rate release limit of 30 microSv/h at 1 m, isolation period is sufficient for 72 h for all of our patients, while 75% of them had dose rates below that limit within 48 h.
- Published
- 2004
219. Helicobacter pylori infection and the risk for coronary artery disease.
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Kountouras J, Zavos C, and Chatzopoulos D
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- Adolescent, Adult, Aged, Causality, Coronary Disease blood, Female, Fibrinogen metabolism, Helicobacter Infections blood, Humans, Male, Middle Aged, Risk Factors, Coronary Disease epidemiology, Helicobacter Infections epidemiology, Helicobacter pylori
- Published
- 2004
220. Apoptosis and autoimmunity as proposed pathogenetic links between Helicobacter pylori infection and idiopathic achalasia.
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Kountouras J, Zavos C, and Chatzopoulos D
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- Animals, Esophageal Achalasia microbiology, Evidence-Based Medicine, Humans, Models, Biological, Apoptosis immunology, Autoimmunity immunology, Esophageal Achalasia etiology, Esophageal Achalasia immunology, Helicobacter Infections complications, Helicobacter Infections immunology, Helicobacter pylori immunology, Helicobacter pylori pathogenicity
- Abstract
Achalasia is a disorder of the oesophagus characterised by increased lower oesophageal sphincter (LOS) tone, lack of LOS relaxation with swallowing and aperistalsis of the body of the oesophagus. The aetiology and pathogenesis of idiopathic achalasia are still unclear, although a viral cause, genetic influences (associations with HLA loci) and autoimmune processes have been postulated. Degeneration and significant loss of nerve fibres, associated with an inflammatory infiltrate of the myenteric plexus in idiopathic achalasia, provide evidence of an immune mediated destruction of the myenteric plexus, possibly through apoptotic process. This concept is reinforced by the concomitant appearance of achalasia and Guillain-Barré syndrome (GBS) and/or Parkinson's disease, where inappropriate initiation of apoptosis has been proposed to underlie the neuronal attrition. In the same respect, Helicobacter pylori (H. pylori) infection has been associated with gastric autoimmunity, and patients infected with H. pylori have been shown to possess autoantibodies that cross-react with antigens expressed on the gastric mucosa. Furthermore, H. pylori is thought to be associated with the development of autoimmune sequelae observed in peripheral neuropathies and GBS, where autoantibodies to specific neural targets have been found to impair native neural function by inducing nerve tissue damage, possibly by apoptosis. Taken together, we assume that H. pylori infection might be a pathogenetic factor of achalasia through induction of autoimmunity and apoptosis. Whether eradication of H. pylori infection may indirectly offer benefit to the pathophysiology of idiopathic achalasia by ameliorating the apoptotic loss of ganglion cells and their axons in the oesophageal wall remains to be elucidated., (Copyright 2004 Elsevier Ltd.)
- Published
- 2004
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221. Whole-body (131)I washout in a patient with metastatic well-differentiated papillary thyroid carcinoma treated with repeated (131)I administration.
- Author
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Chatzopoulos D and Markou P
- Abstract
We describe the case of a 37-year-old male patient suffering from papillary carcinoma of the thyroid gland with pulmonary metastases who after total thyroidectomy on 29/07/1998 was submitted to three treatments with high doses of (131)I and studied as to the whole body clearance of (131)I by measuring the dose rate of (131)I. The patient was referred to us for total ablation of post surgery remnant of thyroid tissue on 19/09/1998. Due to lymphadenic metastases and high Tg values: 450 ng/ml, he was purposely given therapeutically a high dose of 5146 MBq (131)I. On the whole body post-operative scintiscan that followed, a diffuse uptake of (131)I in the lungs and in the thyroid remnant was found. The patient was given 7307 MBq (131)I after 7 months and 5154 MBq of (131)I after another 10 months, because Tg was increased. Whole body scintiscan after the third treatment as mentioned above, showed poor uptake of (131)I in the thyroid gland area and in the lungs. No side effects were noticed, Tg fell to 4.5-7 ng/ml and the patient was in good condition with no abnormal findings on the X-rays or CT of the thorax. After iodine administration whole body measurements of the dose rate of the clearance of (131)I measured by an ionization chamber at a distance of 2 m from the thorax, were performed. For the first treatment effective half-lives of (131)I of the patient, as measured for the two components of the clearance curve, were 4.4 h and 16.8 h respectively. For the second and third treatment clearance curve had only one component and effective half-lives were 22.5 h and 11 h respectively. Remaining activity of (131)I at 48 h was for the first, second and third treatment: 13.3% (685 MBq), 22.8% (1670 MBq) and 4.2% (222 MBq) respectively. We do not know any similar case in the literature with whole body measurements of (131)I clearance in patients undergoing repeated (131)I treatment as above, especially with diffuse pulmonary uptake of (131)I indicating metastatic lesions after the first treatment of (131)I post total thyroidectomy. The interest of the above case also lies on the fact that there were three successive treatments with (131)I and three whole body (131)I measurements. Clearance rate indicated the need for additional treatment and the treatment followed was successful.
- Published
- 2004
222. Induction of apoptosis as a proposed pathophysiological link between glaucoma and Helicobacter pylori infection.
- Author
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Kountouras J, Zavos C, and Chatzopoulos D
- Subjects
- Cytokines metabolism, Glaucoma physiopathology, Heat-Shock Proteins metabolism, Helicobacter Infections physiopathology, Humans, Apoptosis physiology, Glaucoma metabolism, Helicobacter Infections metabolism, Helicobacter pylori metabolism
- Abstract
Although apoptosis is equally important both for the development and for the maintenance of homeostasis in some adult tissues, it can also be associated with disease processes. Current studies indicate that apoptosis is a mechanism of cell death in several important ocular and gastrointestinal diseases including glaucoma, and Helicobacter pylori (H. pylori)-induced upper gastrointestinal disorders and/or extraintestinal diseases, including autoimmune and neurodegenerative ones (Sjögren's syndrome, Guillain-Barre syndrome or Parkinson's disease). Glaucoma is also associated with similar autoimmune and neurodegenerative disorders, characterized by apoptotic loss of specific populations of neurons. Recently, a high prevalence of H. pylori infection has been recognized in patients with chronic open-angle glaucoma. In addition, H. pylori eradication may positively influence glaucoma parameters, thereby suggesting a possible causal link between H. pylori and glaucoma. H. pylori infection may influence the pathophysiology of glaucoma by releasing various proinflammatory and vasoactive substances, as well as by influencing apoptotic process; parameters that may also exert their own effects in the induction and/or progression of glaucomatous neuropathy. Importantly, H. pylori infection and glaucoma share the Fas/FasL and the mitochondria-mediated apoptotic pathways, thereby proposing an apoptotic link in the pathophysiology of both diseases.
- Published
- 2004
- Full Text
- View/download PDF
223. Increased levels of Helicobacter pylori IgG antibodies in aqueous humor of patients with primary open-angle and exfoliation glaucoma.
- Author
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Kountouras J, Mylopoulos N, Konstas AG, Zavos C, Chatzopoulos D, and Boukla A
- Subjects
- Adult, Aged, Aged, 80 and over, Case-Control Studies, Cataract immunology, Cataract microbiology, Exfoliation Syndrome immunology, Glaucoma, Open-Angle immunology, Humans, Middle Aged, Odds Ratio, Osmolar Concentration, Prospective Studies, Antibodies, Bacterial analysis, Aqueous Humor immunology, Exfoliation Syndrome microbiology, Glaucoma, Open-Angle microbiology, Helicobacter pylori immunology, Immunoglobulin G analysis
- Abstract
Purpose: A prospective, nonrandomized, comparative study was carried out to investigate the levels of anti- H. pylori-specific IgG antibodies in the aqueous humor and serum of patients with primary open-angle glaucoma (POAG) and patients with exfoliation glaucoma (XFG), and to compare them with those in age-matched cataract patients., Methods: Aqueous humor was aspirated at the beginning of glaucoma surgery from 26 eyes of 26 patients with POAG, 27 eyes of 27 patients with XFG, and at the beginning of phakoemulsification cataract surgery from 31 eyes of 31 age-matched normotensive cataract patients. Serum samples were obtained the day before surgery from all patients. Anti- H. pylori IgG concentration in the aqueous humor and serum was measured by means of an enzyme-linked immunosorbent assay., Results: The mean concentration (+/- SE) of anti- H. pylori-specific IgG was significantly greater in the aqueous humor samples from patients with POAG (14.27+/-3.86 U/ml) and XFG (14.25+/-3.39 U/ml) than in those from age-matched control cataract patients (4.67+/-1.07 U/ml); ( P=0.006 and P=0.003, respectively). No difference was observed in the levels of H. pylori-specific IgG antibodies between POAG and XFG aqueous humor samples ( P=0.5). Similarly, the serum concentration of anti- H. pylori antibodies was significantly greater in patients with POAG (69.96+/-9.69 U/ml; P=0.013) and XFG (81.37+/-10.62 U/ml; P=0.002) than in the cataract controls (44.16+/-6.48 U/ml). The mean vertical cupping correlated significantly with the titer of anti- H. pylori-specific IgG in the aqueous humor in the POAG patients., Conclusion: H. pylori-specific IgG antibody levels are significantly increased in the aqueous humor and serum of patients with POAG and XFG. Moreover, the titer of anti- H. pylori antibody in the aqueous humor might reflect the severity of glaucomatous damage in POAG patients. These findings support a role for H. pylori infection in the pathobiology of these two common glaucomas.
- Published
- 2003
- Full Text
- View/download PDF
224. Locoregional immunochemotherapy in primary and metastatic liver disease: meta-analysis and review of literature.
- Author
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Kountouras J, Zavos C, Chatzopoulos D, Zavos N, Boura P, and Safioleas M
- Subjects
- Chemotherapy, Adjuvant, Humans, Liver Diseases mortality, Liver Neoplasms mortality, Liver Neoplasms therapy, Treatment Outcome, Immunotherapy, Adoptive, Liver Diseases therapy
- Abstract
Background/aims: Primary and metastatic liver tumors are the most common malignancies that resist conventional chemotherapy and radiotherapy. Several immunotherapies have been attempted for cancer treatment on the basis of stimulating host immune response to tumors and recent development of combined targeting locoregional immunochemotherapy reported with promising results. However, the efficacy of this therapeutic modality is not yet widely established., Methodology: We reviewed the medical literature for publications dealing with the value of locoregional immunochemotherapy in patients with primary or metastatic liver tumors., Results: We found that 5 and 7 studies have been controlled and inadequately controlled, respectively. Among 131 patients with primary liver cancer, 40 were treated with combined locoregional immunochemotherapy, and 20 with systemic immunochemotherapy, and 71 with systemic chemotherapy served as two control groups. Complete or partial response was observed in 32 out of 40 (80%) patients who received combined locoregional therapy, and in 10 out of 20 (50%) systemic immunochemotherapy controls (P = 0.03). Survival was three times higher in the patients who received combined locoregional therapy compared with systemic chemotherapy controls (18 vs. 5.6 months). Recurrence of tumor was higher in systemic immunochemotherapy controls (P = 0.003). Among 286 patients with metastatic liver disease, 180 patients were treated with combined locoregional immunochemotherapy and 106 patients with systemic immunochemotherapy. Response (complete or partial) was observed in 65 out of 98 (66.3%) patients who received combined therapy, and in 4 out of 26 (15.4%) controls (P < = 0.001). Survival was two-fold higher in the patients treated with combined therapy (21 vs. 10.5 months). Tumor recurrence was higher in the systemic immunochemotherapy controls (P < = 0.001)., Conclusions: The observational studies indicate a plausible therapeutic rationale for the introduction of locoregional immunotherapy in patients with primary and metastatic liver disease.
- Published
- 2003
225. Apoptosis in hepatocellular carcinoma.
- Author
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Kountouras J, Zavos C, and Chatzopoulos D
- Subjects
- Carcinoma, Hepatocellular therapy, Humans, Liver Neoplasms therapy, Prognosis, Apoptosis physiology, Carcinoma, Hepatocellular physiopathology, Liver Neoplasms physiopathology
- Abstract
The process of apoptosis plays a crucial role in several physiological as well as pathophysiological processes, and is a fundamental mechanism for the deletion of unwanted, senescent, or damaged cells. Defects in the apoptotic mechanisms or, even more, disturbances of the equilibrium between cellular replication, growth, differentiation and apoptosis favor the growth of preneoplastic and tumoral lesions in the liver. Clinical and molecular medical analyses have yielded a considerable amount of information about liver oncogenesis. Studies on transgenic models of hepatocarcinogenesis have allowed a meticulous examination of the roles of apoptosis, tumor suppressors, DNA repair processes and other events in the clonal expansion and accumulation of genetic lesions. During initiation, there is rapid proliferation and a high amount of apoptosis, whereas in the promotion stage, there is decreased cell death and increased cell proliferation. Accumulating evidence suggests a defective apoptotic process in human hepatocellular carcinoma. Moreover, a range of prognostic factors related to apoptosis might be used in the early assessment of the progress of hepatocarcinogenesis as well as in hepatocellular carcinoma recurrence. Lastly, many potential therapeutic strategies, that induce the apoptotic process in various ways, can be applied to the hepatocellular carcinoma management.
- Published
- 2003
226. Eradication of Helicobacter pylori may be beneficial in the management of chronic open-angle glaucoma.
- Author
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Kountouras J, Mylopoulos N, Chatzopoulos D, Zavos C, Boura P, Konstas AG, and Venizelos J
- Subjects
- Aged, Causality, Comorbidity, Female, Glaucoma, Open-Angle therapy, Humans, Intraocular Pressure, Male, Middle Aged, Prevalence, Visual Fields, Glaucoma, Open-Angle epidemiology, Glaucoma, Open-Angle microbiology, Helicobacter Infections epidemiology, Helicobacter pylori
- Abstract
Background: We have documented a high prevalence of Helicobacter pylori infection in patients with glaucoma., Objective: To evaluate the effect of H pylori eradication on the 2 most commonly used glaucoma parameters: intraocular pressure and visual field., Methods: A total of 41 patients with glaucoma and 30 age-matched anemic controls underwent upper gastrointestinal endoscopies and gastric mucosal biopsies to detect the presence of H. pylori infection by histologic analysis and rapid urease test (CLOtest; Delta West, Draper, Utah). Saliva samples were also tested by CLOtest. Serum anti-H pylori-specific IgG was analyzed by enzyme-linked immunosorbent assay. Helicobacter pylori-positive patients received a triple eradication regimen (omeprazole, clarithromycin, and amoxicillin treatment), and all patients were observed for 2 years while remaining under the same antiglaucoma therapy., Results: Helicobacter pylori was detected in 88% of glaucoma cases and in 47% of controls (P<.001). Helicobacter pylori eradication was successful in 83% of treated patients. At the 2-year clinical end point, glaucoma parameters (mean intraocular pressure and mean visual field parameters) were improved in the subgroup of patients where H. pylori eradication was successful (P<.001 for intraocular pressure; P< or =.01 for visual field parameters), but not in the other patients., Conclusion: Helicobacter pylori eradication may positively influence glaucoma parameters, suggesting a possible causal link between H pylori and glaucoma.
- Published
- 2002
- Full Text
- View/download PDF
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