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Biomedical subjects

G Triantafyllou

Publications and source records attributed to G Triantafyllou.

8 recordsLinked to original sources

Field data analysis and application of a complex water column biogeochemical model in different areas of a semi-enclosed basin: towards the development of an ecosystem management tool.

The Pagasitikos gulf ecosystem is studied through the analysis of experimental field data acquired during several monitoring projects and the application of a complex biogeochemical model. The gulf was separated into three different parts (internal, top central-external, bottom central-external) according to the patterns exhibited by the key ecosystem indicators. Unlike other semi-enclosed gulfs Pagasitikos can be characterised as meso-oligotrophic undergoing periods of P or N limitation. Although the signal of nutrient inputs is not very clear in the field data, their importance is assessed through simulation. Increased phosphate concentrations either due to mixing or due to anthropogenic activities can result in phytoplanktonic blooms with significant contribution by diatoms. The effect of hydrodynamic patterns on primary production has been demonstrated through ecosystem modeling indicating that due to long stratification periods, all nutrients released through the benthic regeneration are trapped in the deeper layers, developing a microbial food web. However when the thermocline erodes nutrients find their way up in the upper layers of the euphotic zone and the system turns into more classical type with primary producers growing significantly faster.

Animals↗

A prospective randomized controlled trial of intravenous ciprofloxacin as an adjunct to corticosteroids in acute, severe ulcerative colitis.

BACKGROUND: The role of antibiotics in the treatment of ulcerative colitis is controversial. This study aims at assessing the therapeutic role of ciprofloxacin as an adjunct to corticosteroids in acute severe ulcerative colitis. METHODS: In this prospective, randomized, double-blind, placebo-controlled trial, 55 consecutive patients fulfilling the criteria of Truelove and Witts for severe ulcerative colitis were randomized on admission to the hospital to receive intravenously ciprofloxacin (400 mg b.i.d.) (n = 29) or placebo (n = 27). All patients received parenteral nutrition, intravenous hydrocortisone (100 mg q.i.d.) and hydrocortisone enemas (100 mg b.i.d.). Patients were assessed after 10 days of continuous treatment, or at any time a severe complication occurred. RESULTS: At study entry, there were no significant differences between treatment groups in any patient or disease-related parameter. Twenty-three of 29 patients (79.3%) treated with ciprofloxacin and 20 of 26 patients (77%) treated with placebo showed substantial improvement and were given oral steroids (P > 0.1). Six patients in each group did not improve (n = 10) or developed complications (n = 2). Nine of these 12 patients underwent emergency colectomy; three patients consented to receive intravenous cyclosporin but did not achieve remission of colitis and they underwent elective colectomy. There were no perioperative or late deaths. CONCLUSIONS: A short course of intravenous ciprofloxacin does not seem to augment the effect of corticosteroids for patients with acute, severe ulcerative colitis.

Acute Disease↗

A prospective randomized controlled trial of oral ciprofloxacin in acute ulcerative colitis.

OBJECTIVES: The aim of this prospective, randomized, controlled trial was to evaluate the role of ciprofloxacin as an adjunct to corticosteroids in acute ulcerative colitis. METHODS: Seventy consecutive patients with mild (n = 37) or moderately active (n = 33) ulcerative colitis were randomized to receive oral ciprofloxacin (250 mg b.i.d., n = 34) or placebo (n = 36) for 14 days. In addition, they were given oral prednisolone (initial dose 20 or 40 mg for mild and moderately active ulcerative colitis, respectively) and rectal betamethasone enemas (2 g at night) for 7-9 weeks. All patients were receiving olsalazine (0.5 g twice daily). At study entry, the groups were similar with respect to age, sex, extent, duration, and severity of disease, and previous treatments. Patients were assessed clinically, endoscopically, and histologically before, at the end of the trial (day 14), and on completion of steroid treatment, or at any time worsening of symptoms or a complication of ulcerative colitis occurred. RESULTS: At the end of the study, 24 patients (70.5%) in the ciprofloxacin group and 26 patients (72%) in the placebo group achieved remission (p > 0.1, Yates chi 2). Ten patients in each group necessitated higher doses of oral (n = 12) or intravenous (n = 8) steroids. Of the latter patients, two underwent emergency colectomy without perioperative deaths. Clostridium difficile toxin A was not detected in nonresponders to ciprofloxacin treatment. CONCLUSIONS: A short course of oral ciprofloxacin treatment does not seem to increase the proportion of patients with active ulcerative colitis going into remission.

Acute Disease↗

The role of colonoscopy in the differential diagnosis of acute, severe hemorrhagic colitis.

BACKGROUND AND STUDY AIMS: This study assesses the diagnostic value of colonoscopy performed at an early stage of a first attack of acute, severe hemorrhagic colitis. PATIENTS AND METHODS: One hundred fourteen consecutive patients were prospectively studied. The colonoscopic diagnosis was compared with the final diagnosis of the colitis, which was based on clinical, microbiological, endoscopic, and histological criteria during the acute illness, but also on the results of a thirty-month follow-up of the patients aiming to confirm whether the colitis was relapsing or nonrelapsing in nature. RESULTS: The colonoscopic diagnosis was ulcerative colitis (UC) in 40, Crohn's disease in four, and infective colitis (IC) in 70 patients. The endoscopic diagnosis was finally confirmed in all 40 UC patients and in 68 of 70 (97.1%) IC patients. Two patients with an initial endoscopic and histological diagnosis of IC presented with typical attacks of UC 28 and 30 months later, respectively. Prominent endoscopic appearances in IC were mucosal edema, erythematous areas, hemorrhagic spots, bleeding, microaphthoid ulcers, and luminal exudate. Although rectal sparing was occasionally seen, endoscopic lesions were continuous and severe in the distal colon, but were patchily and unevenly distributed in other parts of the colon in IC. In UC, prominent colonoscopic findings were bleeding, mucosal friability, granularity, and ulceration; lesions were continuously distributed in the involved area. CONCLUSIONS: Colonoscopy is a useful procedure in the differential diagnosis of severe bloody diarrhea of unknown cause.

Acute Disease↗