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D Demetriou

Publications and source records attributed to D Demetriou.

At least 19 recordsLinked to original sources
PubMed2006

Adequacy of automated peritoneal dialysis with and without manual daytime exchange: A randomized controlled trial.

Until now, it remains unclear whether the addition of manual daytime exchanges or increasing the nightly dialysate flow is the best strategy to optimize automated peritoneal dialysis (APD) treatment. In this open-label randomized controlled crossover trial, 18 patients with high-average (HA) or low-average (LA) peritoneal transport rates sequentially underwent two different APD regimens for 7 days each, with an intermittent washout period of 7 days. 'Manual exchange' treatment was a conventional APD with low nightly dialysate flow and one manual daytime exchange. 'High-flow' treatment was defined by cycler therapy with high dialysate flow but without manual daytime exchange. Creatinine clearances (8.56+/-1.22 vs 7.87+/-1.04 l/treatment, P = 0.011) and urea nitrogen clearances (12.83+/-1.98 vs 11.68+/-1.06 l/treatment, P = 0.014) were significantly increased during 'high-flow' treatment compared to 'manual exchange' treatment. Sodium removal was significantly lower and glucose absorption was higher with the 'high-flow' regimen. Phosphate clearances, beta2-microglobulin clearances, ultrafiltration, and peritoneal protein loss were not different between the two treatment modalities. Subgroup analysis dependent on peritoneal transport types showed that the effect on clearances was most marked and significant in HA transporters, whereas sodium removal was lowest in LA transporters. We conclude that small solute clearances can be significantly improved and middle molecule clearances maintained in APD patients by increasing the nightly dialysate flow instead of adding a manual daytime exchange. However, the possible benefit of better clearances with higher nightly treatment volumes has to be weighed against increased costs and the possible negative impact of impaired sodium removal, especially in LA transporters.

Adult↗
PubMed2000

Twelve months of lamivudine treatment for chronic hepatitis B virus infection in renal transplant recipients.

BACKGROUND: Chronic hepatitis B virus (HBV) infection increases morbidity and mortality in renal transplant recipients (RTR). Lamivudine has shown promising results in patients with chronic hepatitis B, but experience with its use in RTR is limited. METHODS: In a prospective, open labeled, uncontrolled trial, 19 HBsAg(+) RTR were treated with lamivudine for 12 months. HBV-serologic analysis, HBV-DNA quantitation, and HBV genome sequence analysis were performed every 3 months. RESULTS: At baseline 16 patients were HBV DNA(+), 12 patients were HBeAg(+)/Ab (-). After 3 months HBV DNA was negative in 80% of patients. In the 3 patients with elevated liver enzymes, normal values were achieved within 12 weeks. At 12 months 4 of 8 HBeAg(+)/Ab(-) patients on treatment showed HBeAb, two of them with loss of HBeAg. Three patients developed mutations of the HBV polymerase gene associated with lamivudine resistance. CONCLUSIONS: Lamivudine is safe and effective in HB-sAg(+) RTR, the rate of HBe-seroconversion and of lamivudine-resistance is comparable to that of nonimmunosuppressed patients.

Adult↗
PubMed2000

Multiple complex coronary plaques in patients with acute myocardial infarction.

BACKGROUND: Acute myocardial infarction is believed to be caused by rupture of an unstable coronary-artery plaque that appears as a single lesion on angiography. However, plaque instability might be caused by pathophysiologic processes, such as inflammation, that exert adverse effects throughout the coronary vasculature and that therefore result in multiple unstable lesions. METHODS: To document the presence of multiple unstable plaques in patients with acute myocardial infarction and determine their influence on outcome, we analyzed angiograms from 253 patients for complex coronary plaques characterized by thrombus, ulceration, plaque irregularity, and impaired flow. RESULTS: Single complex coronary plaques were identified in 153 patients (60.5 percent) and multiple complex plaques in the other 100 patients (39.5 percent). As compared with patients with single complex plaques, those with multiple complex plaques were less likely to undergo primary angioplasty (86.0 percent vs. 94.8 percent, P = 0.03) and more commonly required urgent bypass surgery (27.0 percent vs. 5.2 percent, P < or = 0.001). During the year after myocardial infarction, the presence of multiple complex plaques was associated with an increased incidence of recurrent acute coronary syndromes (19.0 percent vs. 2.6 percent, P < or = 0.001); repeated angioplasty (32.0 percent vs. 12.4 percent, P < or = 0.001), particularly of non-infarct-related lesions (17.0 percent vs. 4.6 percent, P < or = 0.001); and coronary-artery bypass graft surgery (35.0 percent vs. 11.1 percent, P < or = 0.001). CONCLUSIONS: Patients with acute myocardial infarction may harbor multiple complex coronary plaques that are associated with adverse clinical outcomes. Plaque instability may be due to a widespread process throughout the coronary vessels, which may have implications for the management of acute ischemic heart disease.

Aged↗
PubMed2000

Beneficial effects of atorvastatin in the treatment of hyperlipidemia after renal transplantation.

Despite the availability of various lipid lowering drugs, the treatment of hyperlipidemia, one of the most important risk factors for morbidity and mortality after organ transplantation, remains a therapeutic challenge. We investigated the safety and efficacy of a new HMG-CoA reductase inhibitor, atorvastatin, in renal transplant patients whose serum lipids were insufficiently controlled by diet and treatment with other lipid lowering drugs. Twenty-four patients (14 males/10 females; mean age 51.2 +/- 2.3 years) were converted to low dose atorvastatin (10 mg/day) at a mean of 67.7 +/- 8.6 months after renal transplantation and prospectively followed for 3 months after initiation of the study drug. HDL, LDL, and total cholesterol, triglycerides, serum creatinine and CPK levels were evaluated pre (-3, -1, 0 months) and post conversion (+1, +3 months). In the eighteen patients who completed the study, low dose atorvastatin therapy led to a significant reduction in total cholesterol (304.6 +/- 13.2 vs. 247.6 +/- 12.0 mg/dl; p = 0.007) and LDL cholesterol (191.9 +/- 9.0 vs. 141.8 +/- 14.7 mg/dl; p < 0.0001) and a modest reduction in serum triglyceride levels at three months after conversion. We conclude that low dose atorvastatin (10 mg/day) can be successfully used and appears to be safe in the treatment of posttransplant hyperlipidemia. Its long-term effects on patient morbidity and mortality as well as graft survival should be investigated in larger and more prolonged prospective trials.

Adult↗
PubMed2000

Vasoactive substances in renal transplantation.

During and after transplantation the kidney experiences a variety of insults that result in functional impairment and structural damage. These changes are mediated or influenced by hormones, cytokines, enzymes and growth factors, which are excreted by endothelial, graft parenchymal as well as by graft infiltrating cells. This review evaluates the pathophysiological role of vasoactive substances (for example, the vasoconstrictors angiotensin II and endothelin, as well as vasodilators such as nitric oxide, adrenomedullin and atrial natriuretic peptide) in kidney transplantation and summarizes recent reports that indicate that targeting vasoactive substances may represent effective therapeutic strategies for the achievement of long-term allograft survival.

Adrenomedullin↗
PubMed2000

New developments in clinical immunosuppression.

Over the last few years, the armamentarium of immunosuppressants has been enriched by a variety of new drugs, that have helped to further reduce the incidence of acute rejection episodes after kidney transplantation. Nevertheless the search for new compounds drugs continues, until tolerance, the ultimate goal of transplantation medicine can be achieved. Meanwhile we should appreciate that neither all drugs nor all patients are equal and tailor the immunosuppression to the patients' needs. To define patient groups who benefit most from different immunosuppressive protocols especially in regard to long term allograft and patient survival will warrant further prospective controlled trials.

Animals↗
PubMed1999

5'-hydroxycotinine-N-oxide, a new nicotine metabolite isolated from rat urine.

1. 5'-Hydroxycotinine-N-oxide, 5-(3-pyridyl-N-oxide)-5-hydroxy-1-methyl-pyrrolidone-2, was identified as a new in vivo metabolite of nicotine. 2. The new metabolite was isolated from the urine of rats treated with S-nicotine and characterized using chemical and spectrometric methods. 3. 5'-Hydroxycotinine-N-oxide was synthesized and characterized by MS and by infrared as well as 1H- and 13C-NMR spectroscopy. 4. Identity of the new metabolite with synthetic 5'-hydroxycotinine-N-oxide was demonstrated by comparing the MS and 1H-NMR spectroscopy data as well as by co-chromatography of a spiked urine sample.

Animals↗
PubMed1997

Study of the effects of thermotherapy in benign prostatic hypertrophy.

UNLABELLED: Prostatic transurethral thermotherapy was evaluated clinically using the Prostcare microwave system of the Bruker Company, which uses a microwave radiometer to measure and control intraprostatic temperature. OBJECTIVES: The aim of our study was to evaluate the immediate histological lesions induced in the prostatic tissue depending on the temperatures delivered to the prostate; the histological changes when adenectomy is carried out after thermotherapy, and the endoscopic appearance of the prostatic fossa 48 h, and 1, 2, 3 and 6 months after thermotherapy. METHODS: Our study was divided into three stages: in the first stage, we conducted thermotherapy in 10 patients in whom suprapubic adenectomy was indicated. During thermotherapy, a multipoint fiber-optic receptor and two thermocouples were implanted into the prostage gland at a distance of 5-15 mm from the urethra. Adenectomy was carried out 10 min after thermotherapy; the second stage of our study concerned the changes seen over time. We heated adenomas using the same protocol and carried out adenectomy 24, 48, 72 h, and 1 week, 6 weeks and 3 months after thermotherapy, and lastly, we studied the endoscopic appearance after a single heating-session of 30 min by endoscopic controls at different times after thermotherapy (48 h, 1, 2, 3 and 6 months after thermotherapy). RESULTS: Macroscopic appearance: necrotic lesions measured 30 mm in length on average. Necrosis was roughly circumferential. Immediate histological aspect: in all cases, histological examination showed coagulation necrosis with periurethral thromboses. Histological changes: at 8 days, necrosis intensity was maximal and histological structures were difficult to identify. Endoscopic appearance: 3 months after thermotherapy, the typical endoscopic appearance was a large periurethral cavity. There was a sharp demarcation between untreated areas and cicatricial tissue. CONCLUSION: The efficacy of thermotherapy depends on the radiometric temperature, which should reach 47 degrees C (i.e. a temperature of 55-65 degrees C delivered to the prostate), and a rapid increase in temperature, i.e. in the power applied, which should reach the thermal radiometric level of 47 degrees C in 5 min. As soon as necrosis is obtained, the power is automatically reduced. Using this protocol, heating proves effective in 30 min.

Humans↗
PubMed1996

[Percutaneous nephrostomy in malignant ureteral obstruction].

OBJECTIVE: To assess survival length and quality of life in patients with a percutaneous nephrostomy (PN) for malignant tumour and postrenal anuria. PATIENTS AND METHODS: Case records were analysed of 50 patients (39 men, eleven women; mean age 65.6 years) with postrenal anuria due to malignancy who had undergone ultrasound-directed PN under local anaesthesia for urinary drainage. Particular attention was paid to the course of the disease from nephrostomy until death. RESULTS: Survival time after PN ranged from 4 days to 16 months, averaging 4.3 months. 26 patients (52%) had died after 3 months, 41 (82%) after 6 months. The patients had spent on average 44.5% of their remaining life in hospital. After an initial improvement in their state, cancer-produced pain and complications soon set in and often required operative intervention. CONCLUSION: The achieved prolongation of survival time did not always meet the patient's own wishes. Detailed explanation and information to patient and family before PN is therefore urgently required.

Adult↗
PubMed1995

Survival of enterobacteria in liquid cultures during microwave radiation and conventional heating.

Bacteria in food have been reported to survive in larger numbers after processing by microwave radiation than after conventional processing. The bactericidal effect of a domestic microwave oven (SHARP R-7280) on certain pathogenic enterobacteria species was investigated in vitro, in comparison with conventional heating (boiling). The death rates of different nosocomial strains of Escherichia coli, Salmonella sofia, Salmonella enteritidis, Proteus mirabilis and Pseudomonas aeruginosa were tested. The microwave oven and the conventional heating system used were both calibrated in order to calculate temperatures from exposure times. For each strain duplicate samples of 25 ml of pure culture with concentrations at least 10(6) cfu/ml were exposed to microwave radiation. An equal number of samples of the same volume and concentration were exposed to conventional heating. Subsequently all samples were examined qualitatively and quantitatively following standard microbiological procedures. The results indicate that microwaves have an efficient bactericidal effect on the enterobacteria in liquid cultures.

Dose-Response Relationship, Radiation↗
PubMed1994

[Epididymal leiomyosarcoma. A case report with review of the literature].

The authors report the 14th case of leiomyosarcoma of the epididymis in a 67-year-old man. Treatment consisted of radical left orchidectomy without adjuvant chemotherapy or radiotherapy. The patient is free of local or distant recurrence with a follow-up of 2 years. The other 13 cases reported in the literature are briefly reviewed.

Aged↗
PubMed1993

High-performance liquid chromatographic determination of nicotine and its urinary metabolites via their 1,3-diethyl-2-thiobarbituric acid derivatives.

The 1,3-diethyl-2-thiobarbituric acid (DETBA) assay for nicotine metabolites has been improved so that it can be used to determine the concentrations of nicotine and up to 12 metabolites in the urine of humans and laboratory animals, including phase 2 metabolites. The products of beta-glucuronidase cleavage found in human urine were mainly trans-3'-hydroxycotinine, cotinine, and a small amount of nicotine. Following isolation, spectroscopic analyses showed the structure of the nicotine DETBA derivative to be the one-to-one ring-opening product of DEBTA and the cyanopyridinium salt of nicotine.

Animals↗
PubMed1992

[Ureteral risk in celioscopic surgery].

In recent years, there has been a significant improvement in laparoscopic surgery which had led to more and more frequent use of this technic in various cases. As a consequence, the ureteral injury which have been a less common iatrogenic pathologic up to know is likely to be more and more frequent in the years to come. The authors present 2 cases of 28 and 36 years old patients. In both cases the laparoscopy was indicated for gynecologic pathology. The healing ureteral occurred in those cases during a revealing postoperative peritonitis. Treatment consisted in healing up the lesion by ureteral stent. Treatment and evolution of this injury are discussed.

Adult↗
PubMed1992

[Partial cystectomy: and alternative to radical cystectomy? Apropos of a series of 75 patients].

From a retrospective series of 75 patients, we try to determine the place of this treatment with respect to bladder urothelial cancer. Of our 75 patients the breakdown of tumours according to their stage is the following: PTA: 16 (21.3%) PT1: 12 (16%) PT2: 21 (28%) PT3 A: 15 (20%) PT3 B: 7 (9.3%) PT4: 4 (5.4%) 47 patients benefited from a complete check up of tumoural spread which is negative in any case. In 28 cases, an uretero-vesical reimplantation was necessary for carcinologic reasons. None of the patients benefited from chemotherapy and/or radiotherapy in pre or post-operative period. Mortality was 4% (3 cases) and morbidity 8% (6 cases)- Sixty two Patients were followed-up at 5 years. The results are expressed according to different carcinologic parameters. The overall rate of recurrence is 61.2% (38/62). The actuarial survival corrected at 5 years, all stages and grades included, is 53.2% (32/62). There was no recurrence in 18 patients (29%) and 29 patients preserved their bladder. The advantages of partial cystectomy are obvious: Its mortality and morbidity are weak. It also preserves the sexual function and mainly avoids resorting to urinary derivations. As a principle these indications apply to a small percentage of invasive tumours T2-T3 A located in the mobile part of the bladder that is unifocal and of small size (< 4 cms).

Actuarial Analysis↗
PubMed1991

[Is adrenalectomy always advisable in tumor nephrectomy?].

Since the addition of ultrasonography and computerized tomography to the diagnostic tools used for the recognition of renal tumor masses, detection of renal cell carcinomas has been much earlier and more reliable than formerly. Between July 1981 and June 1990, 335 patients without distal metastases underwent radical nephrectomy for renal cell carcinoma. In only 2.6% of the patients were adrenal metastases found, exclusively with stage pT3 tumors. The results of this review suggest that the adrenal gland need not be removed with the radical nephrectomy specimen in the case of tumors staged T1 or T2 if the adrenal CT scan is normal.

Adrenal Gland Neoplasms↗
PubMed1977

Laboratory studies and clinical features in a case of boomslang envenomation.

A case of boomslang (Dispholidus typus) envenomation is reported. Coagulation studies carried out within 2 hours of the patient's being bitten showed unrecordable prothrombin and activated partial thromboplastin times. The fibrinogen and factors V and VIII were severely depleted. Abnormal liver function tests were also documented. These abnormalities were corrected by treatment with specific antivenom. A haemolytic-uraemic syndrome was not observed.

Adult↗