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G A Barbalias

Publications and source records attributed to G A Barbalias.

At least 19 recordsLinked to original sources
PubMed2006

Risk of tuberculosis in dialysis patients: association of tuberculin and 2,4-dinitrochlorobenzene reactivity with risk of tuberculosis.

BACKGROUND: Dialysis patients are at increased risk of tuberculosis (TB) and anergy due to attenuated cellular immunity. AIM: To define specific risks of TB in anergic and non-anergic dialysis patients. METHODS: A total of 272 dialysis patients were enrolled in this prospective study over a 36-month follow-up. Entering the study, participants had Mantoux and 2,4-dinitrochlorobenzene skin tests and their cell-mediated immunity (CMI)-index was estimated. Patients were classified as anergic (CMI-index<or=2 and Mantoux<or=4 mm) or non-anergic. Specific relative risks of TB were then calculated, using data from both the general population and 49 non-uremic health care workers. The independent effect of sex, age and diabetes mellitus was determined using Cox's proportional hazard method. RESULTS: Among the 116 (42.6%) anergics 13 (11.2%), and among the 156 non-anergics 11 (7%) developed active tuberculosis. Anergics had a significantly higher risk of TB than non-anergics (Adjusted Relative Risks, 98.3, 95% CI 58.65-113.6 versus 61.6, 95% CI 13.6-72.1, P=0.003). Tuberculin reactivity was weakly associated with the subsequent risk of TB (r=0.51). The latter showed a steadily decreasing trend with increasing CMI-index (r=-0.99). CONCLUSION: Anergy distorts the association of tuberculin reactivity with risk of TB. Anergic dialysis patients are at increased risk of developing active TB and chemoprophylaxis is justified in them too.

Adult↗
PubMed2006

Primary adrenal tuberculosis: role of computed tomography and CT-guided biopsy in diagnosis.

A case of isolated, bilateral, adrenal tuberculosis is presented. A 25-year-old male was admitted to the hospital due to lumbar pain, fever, weight loss and anorexia. Abdominal ultrasonography and computed tomography demonstrated bilateral adrenal enlargement. Laboratory investigations were remarkable for adrenal insufficiency. The Mantoux reaction was positive but there was no evidence of lung or urinary infection. CT-guided biopsy of the left adrenal gland was performed and established the diagnosis of adrenal tuberculosis.

Adrenal Gland Diseases↗
PubMed2004

Assessment of encrustations on polyurethane ureteral stents.

PURPOSE: To determine the composition and the extent of crystalline (and other) encrustation on ureteral catheters inserted under sterile conditions in stone formers, in comparison with catheters of the same type inserted in nonstone formers for the same time but for different clinical reasons. MATERIALS AND METHODS: Forty consecutive self-retained polyurethane pigtail ureteral catheters removed by cystoscopy between November 2000 and February 2002 were studied, 30 from stone formers and 10 from patients without stone histories. The mean dwelling time was 55 days for the stone formers and 79 days for the other patients. The encrustations were collected and analyzed with Fourier-transform infrared spectroscopy, powder X-ray diffraction, or both. The stones from nine of the patients were also subjected to the same spectroscopic analysis. Representative sections of the catheters were investigated by scanning electron microscopy and energy-dispersive X-ray analysis. RESULTS: The most common encrustation in stone formers was calcium oxalate monohydrate. In patients without stones, deposits of organic compounds were found consistently. The mean mass of encrustation of stone formers was larger (71.05 mg) than that of patients without stones (1 mg). CONCLUSIONS: Calcium oxalate is the predominant type of encrustation on ureteral catheters in stone formers. Prevention of heavy encrustation should be directed to therapeutic measures concerning calcium oxalate lithiasis and development of new materials by the medical industry that are less prone to encrustation.

Calcinosis↗
PubMed2002

The use of the tissue adhesive enbucrilate (histoacryl) in the treatment of symptomatic nephroptosis.

PURPOSE: To evaluate the use of the tissue adhesive enbucrilate in the treatment of symptomatic nephroptosis. MATERIALS AND METHODS: We performed adhesive nephropexy in 9 patients who presented with well-documented symptomatic nephroptosis that was demonstrated with intravenous pyelography and/or radionuclide renogram studies. The ptotic kidney was fixed on the psoas muscle using 0.5 ml of enbucrilate (Histoacryl). RESULTS: Adhesive nephropexy was successful in all 9 patients. Average operative time was 37 min. Postoperative opioid analgesia duration and hospital stay were limited (mean 2 and 4.4 days, respectively). Most patients returned to normal activity within 2 weeks (mean 14.2 days). Mean follow-up was 25 months and showed postoperatively a good anatomical result in radiographic studies as well as significant pain alleviation (mean 1 vs. 7 preoperatively, on a 10-point scale, p < 0.005 Wilcoxon rank test). CONCLUSIONS: The tissue adhesive enbucrilate seems to be a safe, efficient agent to obtain good results in a simple, quick approach in the surgical treatment of symptomatic nephroptosis.

Adult↗
PubMed2001

Urologic manifestations of multiple sclerosis: proposed treatment algorithms.

PURPOSE: A detailed clinical management of the urological manifestations of multiple sclerosis (MS) is presented as it is practiced in our department, and therapeutic algorithms are constructed. MATERIALS AND METHODS: One hundred and ten patients were consecutively and prospectively studied with a clinical syndrome of MS. ranging in age from 32 to 65 years of age. Clinical diagnosis of the voiding dysfunction associated with MS was classified as a malfunction causing either problems of bladder evacuation, or storage, or a combination of both. RESULTS: All patients were initially managed in a conservative way avoiding surgical procedures and following primarily pharmacologic treatment, because of the quite common reversibility of MS. The detailed management of the related voiding dysfunction is given by the proposed algorithms. CONCLUSIONS: Our purpose was to present the algorithms that can help the practicing physician to come to reasonable conclusions as to therapeutical choices directed to specific pathophysiologic characteristics of voiding dysfunction related to MS.

Adult↗
PubMed2001

Clinical management of the neurourological syndrome associated with multiple sclerosis and correlations to grade of the disease.

PURPOSE: In this study a detailed clinical management is presented as it is practiced in our department, and possible correlations between grade of the disease and therapeutic responses are examined. MATERIALS AND METHODS: One hundred and ten patients were consecutively and prospectively studied with a clinical syndrome of MS, ranging in age from 32 to 65 years of age. Clinical diagnosis of the voiding dysfunction associated with MS was classified as a malfunction causing either problems of bladder evacuation, or storage, or a combination of both. Therapeutic responses of the voiding dysfunction were correlated with grade of the disease. Mean follow up period was 54 months. RESULTS: All patients were initially managed in a conservative way avoiding surgical procedures and following primarily pharmacologic treatment, because of the quite common reversibility of MS. A possible correlation of response to treatment according to grade of the disease was studied. There was significant difference in the response to drug treatment among patients of different grades favoring grade 1 patients with both storage and evacuation voiding dysfunction. CONCLUSIONS: Our suggested treatment has secured the conversion of a high pressure into a low pressure vesicourethral system, thus obviating possible risk factors for the upper urinary tract and the bladder itself. Therapeutic responses were dependent upon the grade of the disease.

Adult↗
PubMed2001

Vesicourethral dysfunction associated with multiple sclerosis: correlations among response, most prevailing clinical status and grade of the disease.

PURPOSE: In the present study we have performed a correlation of the most prevailing clinical conditions of multiple sclerosis (MS) with overall drug response and the grade of the disease. MATERIALS AND METHODS: One hundred and ten patients were consecutively and prospectively studied with a clinical syndrome of MS, ranging in age from 32 to 65 years of age. In the present study we evaluated the patients with DESD (n = 35), detrusor hyperreflexia (n = 32), and/or low compliance (n = 8). The latter three conditions were considered as the most threatening, and thus a correlation with the drug response and the grade of the disease was attempted. RESULTS: All patients were initially managed in a conservative way avoiding surgical procedures and following primarily pharmacologic treatment, because of the quite common reversibility of MS. Our results suggest that there is no correlation between the prevailing clinical status and drug response (p = 0.06) or grade of the disease (p = 0.07). The only statistically significant correlation was seen between grade of the disease and overall drug response (p < 0.0001) CONCLUSIONS: Therapeutic responses were dependent upon the grade of the disease. The continuation of this study recruiting more patients into various subgroups of voiding dysfunction will further validate the statistical correlations among disease grade and therapeutic responses.

Adult↗
PubMed2001

Metal stents for the management of atherosclerotic renovascular disease.

PURPOSE: We report on our experience with the use of metal stents for the treatment of atherosclerotic renovascular disease. PATIENTS AND METHODS: Since 1996, 62 patients (mean age 67 years) with ostial atherosclerotic renal artery stenosis were treated successfully by placement of metal stents. All patients presented with renovascular hypertension, and eight had additionally impaired renal function. In 12 patients, stents were placed bilaterally. In 54 patients, the introduction of stents was performed as the primary mode of treatment, and in the remaining 8 patients, the positioning of the endoprosthesis was deemed necessary because of recurrence of stenosis previously treated by renal percutaneous transluminal angioplasty (PTA). The patients were followed for a mean period of 18 months (range 9-48 months). RESULTS: Positioning of the endoprosthesis was successful in all patients. No major complications were reported. The 18-month patency rate was 77.4% (48 patients). Hypertension resolved in 39 patients and showed a trend to improvement in 15 patients. We observed no improvement of renal function in the eight patients who had impaired function prior to the procedure. CONCLUSION: Implantation of metal stents is a safe and effective method for the treatment of atherosclerotic renal artery stenosis and certainly presents an important alternative to renal PTA.

Aged↗
PubMed2001

Coated v noncoated ureteral metal stents: an experimental model.

PURPOSE: The purpose of the present study was to compare the standard metal stents with internally and externally coated metal stents in the pig model. MATERIALS AND METHODS: In nine female pigs weighing between 25 and 30 kg, the metal stents were randomly placed in either the right or left ureter, for a total of 18 stented ureters. Six ureters were stented with a Wallstent (Schneider, Zurich, Switzerland), six with a Passager stent (Boston Scientific, Natick, MA, USA), and six with a Corvita endoluminal graft (CEG) (Boston Scientific, Natick, MA, USA). Patency was examined by nephrostotomography 24 hours and 21 days after the initial procedure. RESULTS: Free flow of urine through the stents into the bladder was revealed in all ureters with the exemption of four cases where a Passager stent migrated into the bladder, jeopardizing ureteral patency. The Wallstent generated mild inflammation with metaplasia of the urothelium; the CEG a more pronounced inflammatory response in the adjacent ureter; and the Passager stent severe inflammatory reaction with necrosis of the urothelium. The sections of the Wallstents revealed the presence of a mild polypoid reaction adherent to the internal surface of the devices. The coated stents showed no tissue ingrowth through the lining material into the ureteral lumen, and thus, the urothelium was compressed beneath the prostheses. CONCLUSIONS: Our experimental results suggest that the standard Wallstent generates less inflammation of the surrounding tissues than coated stents. The coated stents have the advantage of minimal tissue ingrowth but have a tendency to migrate toward the bladder.

Animals↗
PubMed2000

Interstitial cystitis: bladder training with intravesical oxybutynin.

PURPOSE: We assess the efficacy of intravesical administration of oxybutynin chloride in patients with interstitial cystitis. MATERIALS AND METHODS: The study included 36 women with a mean age of 45 years with a diagnosis of interstitial cystitis. Patients were treated with gradual intravesical instillation of saline oxybutynin solution (oxybutynin group) or gradual filling of simple saline (control group). Evaluation parameters consisted of symptom problem index, voids per day, volume per void, functional bladder capacity, volume at first sensation, cystometric bladder capacity and cystometric volume at first sensation. RESULTS: Statistically significant improvement of all evaluated parameters was found in both groups. When comparing the outcomes statistically significant improvement of parameters favored the oxybutynin group. CONCLUSIONS: Bladder training alone produces a satisfactory result by gradually expanding the bladder, and an additional statistically significant improvement is evident with intravesical oxybutynin.

Administration, Intravesical↗
PubMed2000

Immunohistochemical detection of retinoic acid receptor-alpha in prostate carcinoma: correlation with proliferative activity and tumor grade.

BACKGROUND: The use of retinoids as differentiation therapy is a novel approach to prostate cancer. Retinoids act via their own nuclear receptors, RARs and RXRs, modulating gene activity, cell growth and differentiation. This study provides new data on the content and cellular distribution of RARalpha protein in prostate cancer specimens, in correlation to tumor grade and proliferative activity. MATERIAL AND METHODS: A total of 84 cases of primary prostate carcinoma, divided into 3 subgroups according to tumor grade, were immunohistochemically evaluated for retinoic acid receptor-alpha (RARalpha) and Ki67 using the streptavidin/peroxidase method on formalin fixed, paraffin embedded tissues. RESULTS: RARalpha positivity was detected in all cases of prostatic carcinoma, with a more profound expression in well differentiated cancers. A statistically significant correlation between RARalpha staining and tumor grade was found (ANOVA, p < 0.031). Ki67 immunoreactivity was present in 35.7% of cases, but no correlation with tumor grade was found. When RARalpha staining was correlated with Ki67 positivity, a statistically significant correlation was present (unpaired t-test, p < 0.003). CONCLUSIONS: These findings indicate that RARalpha expression is correlated to some extent with tumor grade and its presence is more profound in highly proliferative tumors. Further studies are needed to establish the possible clinical value of the immunohistochemical evaluation of RARalpha content in tumor specimens.

Aged↗
PubMed2000

Percutaneous treatment of large symptomatic renal cysts.

PURPOSE: To evaluate the efficacy of alcohol in combination with tetracycline for the treatment of symptomatic renal cysts. PATIENTS AND METHODS: Twenty-four patients age 45 to 77 years (mean 66 years) with a large (5-13-cm; mean 7.5-cm) symptomatic renal cyst associated with flank pain were treated by aspiration under ultrasound guidance and injection of alcohol and tetracycline. Patients were followed with ultrasonography at 1, 6, and 12 months and once a year thereafter. RESULTS: The aspirated volume ranged from 65 to 1500 mL (mean 360.5 mL). Two patients experienced mild pain during alcohol injection, but the procedure was completed successfully. One patient reported severe pain after tetracycline injection. The tetracycline was immediately aspirated, and the procedure was then aborted. The remaining patients were relieved of their symptoms after treatment, and they remained symptom free during a mean follow-up of 20 months (range 7-36 months). CONCLUSIONS: The combination of alcohol and tetracycline is safe and effective and offers a very favorable minimally invasive therapeutic alternative for the treatment of symptomatic renal cysts.

Aged↗
PubMed2000

Liposome-coated metal stents: an in vitro evaluation of controlled-release modality in the ureter.

PURPOSE: In vitro preparation of liposome-covered metal stents and loading of liposomal drug formulations that will slowly release the drug in the vicinity of the stent. MATERIALS AND METHODS: Polytetrafluoroethylene-coated stents were used. Large multilamellar (MLV) liposomes (phosphatidylcholine:cholesterol 1:1 mol/mol), empty or entrapping the corticosteroid anti-inflammatory drug, dexamethasone, were prepared by the thin-film hydration method and applied to pieces of stent using a simple and mild evaporation technique. Initially, a freeze-drying method for applying liposomes to stents was also evaluated, but it failed to produce stents that efficiently retain liposomal lipid when incubated in an aqueous environment. The presence of liposomes on the stent surface was confirmed by scanning electron microscopy. RESULTS: After analyzing the release of liposomal lipid (using a phospholipid assay) and liposomal drug (by a modified dexamethasone high-pressure liquid chromatography method) in an in vitro system developed to simulate in vivo conditions, it was found that 39.11+/-6.8% of the lipid and 50.84+/-5.48% of the drug was released from the stent pieces during 48 hours of incubation in the presence of artificial urine. The amount of dexamethasone released from stents during their application procedure was found to be negligible in an in vitro dry run. CONCLUSION: The use of stent-associated liposomal drug formulations as slow-release depots could be an efficient method of treating the untoward event of ureteral stent obstruction.

Chromatography, High Pressure Liquid↗
PubMed2000

Metallic stents in gynecologic cancer: an approach to treat extrinsic ureteral obstruction.

OBJECTIVE: We report on our experience with the use of self-expandable metal stents for the treatment of extramural ureteral obstruction in patients with gynecologic cancer to restore ureteral patency and to alleviate the ureterectasis and hydronephrosis proximal to the ureteral narrowing. METHODS: Fourteen women (mean age 48 years) with obstructive uropathy secondary to gynecologic malignancies were treated successfully by placement of Wallstent self-expandable intraureteral metallic stents. The patients were followed for a mean period of 15 (range 9-24) months. RESULTS: Obstructive uropathy was resolved in all cases. In 1 patient placement of an additional, totally coaxial, stent was considered necessary because of tumor ingrowth, occurring 6 months after the procedure. In another patient, tumor overgrowth invading the borderline area between the proximal ureteric end and the metallic prosthesis was seen 12 months after stent placement causing obstruction. Thus, an additional Wallstent was implanted overlapping the initially placed stent. Patency was achieved in all the remaining ureters, during the follow-up period, without any need for further intervention. CONCLUSION: Implantation of self-expandable metal stents is a safe and effective method for bypassing ureteral obstruction due to gynecologic malignancies.

Adult↗
PubMed2000

Encrustation of a metal alloy urinary stent: a mechanistic investigation.

MATERIALS AND METHODS: A section of a metal stent consisting mainly of tantalum coated partially by strongly adhering calcium oxalate monohydrate (COM) crystals was immersed in supersaturated solutions prepared from calcium chloride and sodium oxalate at 37 degrees C and ionic strength 0.15 M in NaCl. Abstract OBJECTIVES: To investigate the kinetics of encrustation of a metall alloy urinary stent system in vitro by calcium oxalate and characterize the crystals forming from solutions supersaturated with respect to all calcium oxalate hydrates. RESULTS: The COM-coated stent mineralized upon immersion in the supersaturated solutions. The process was monitored with a calcium ion-selective electrode and the rates were measured at conditions of sustained solution supersaturation. COM crystals formed on the stent and the rate of COM crystal growth yielded a second-order dependence on the solution supersaturation. CONCLUSIONS: The deposition of COM crystals on the metal stents coated partially with COM crystals by adhesive forces was found to be most important for the acceleration of the encrustation process. The dependence of the rates on the solution supersaturation suggested absence of secondary nucleation and a surface-controlled process for the encrustation process.

Alloys↗
PubMed2000

Cellular distribution of retinoic acid receptor-alpha in benign hyperplastic and malignant human prostates: comparison with androgen, estrogen and progesterone receptor status.

OBJECTIVES: Retinoids are unique modulators of gene activity, cell growth and differentiation by binding to a series of nuclear receptors, i.e. all-trans-retinoic acid receptors (RAR) or 9-cis-retinoid receptors (RXR). In this study, the expression of RARalpha was immunohistochemically evaluated in benign, hyperplastic and malignant prostatic tissue and correlated with sex steroid receptor status. METHODS: Twenty-four cases of BPH and 139 cases of primary prostatic carcinoma were evaluated for RARalpha expression in correlation with androgen (AR), estrogen (ER) and progesterone (PGR) receptor staining, as well as with tumor grade. RESULTS: RARalpha was detected in the nuclei of epithelial cells in both BPH and prostate carcinoma cases. A modest inverse relationship with grade was present, especially for grade I and grade II tumors. AR staining was intense and a strong inverse relationship with grade was revealed. Although ER and PGR showed nuclear staining in prostatic epithelium, the overall expression for these receptors was low. When RARalpha content was compared to the nuclear AR expression, at least two-fold higher RARalpha levels were observed in AR+ grade II and grade III tumors. CONCLUSIONS: RARalpha expression can be immunohistochemically evaluated in formalin-fixed paraffin-embedded prostatic tissue. RARalpha expression is significantly elevated in AR+ moderately and poorly differentiated prostate carcinomas. Immunohistochemical determination of RARalpha content may be useful in defining the patient subsets in which retinoid-based treatment may be of clinical value.

Aged↗
PubMed2000

Pheochromocytoma of the urinary bladder presenting only with macroscopic hematuria.

Pheochromocytoma of the bladder is an unusual tumor that typically presents with hypertensive crises related to micturition. We describe a case of bladder pheochromocytoma in a 42-year-old female in which macroscopic hematuria was the only alarming symptom. The diagnostic and operative issues of this type of tumor are discussed, along with the challenging treatment option of transurethral resection. Diagnosis, treatment and follow-up trends of this rare tumor are reviewed.

Adult↗