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A Farkas

Publications and source records attributed to A Farkas.

At least 55 records · Page 3Linked to original sources
PubMed2001

Tandem CAG repeats of the androgen receptor gene and prostate cancer risk in black and white men.

The most common malignancy in men worldwide is cancer of the prostate. Androgens play a direct role in normal and malignant growth of prostate cells via the androgen receptor (AR). This study analyzed the polymorphic CAG repeat sequence in exon 1 of the AR gene to determine if the number of repeats might be an indicator of prostate cancer risk or aggressive disease. DNA was extracted from blood samples of 20 black and 20 white men with well-documented prostate cancer and 40 healthy controls (20 blacks and 20 whites). PCR amplification was followed by gel electrophoresis and DNA sequencing. This region normally contains between 9 and 29 repeats. Patients and controls both had minor variations in the number of repeats, which ranged from 13 to 27 with 21 being the most frequent allele. Black controls and patients both had a mean of 20 +/- 3 repeats; in whites the mean was significantly lower in patients than controls (21 +/- 2 versus 23 +/- 2; p = 0.004). Combined black and white patients also had a lower number than the combined group of controls (20 +/- 3 versus 22 +/- 3; p = 0.02). Similarly, black and white patients with aggressive disease had a lower number than patients whose disease was more slowly progressive (19 +/- 2 versus 22 +/- 3; p = 0.02). We conclude that the small differences in the number of CAG repeats in both black and white patients do not appear to be a strong indicator of risk or aggressive disease but that this size polymorphism may be one of many genetic and environmental risk factors involved in prostate cancer.

Black People↗
PubMed2001

Feminizing genitoplasty in patients with 46XX congenital adrenal hyperplasia.

Congenital adrenal hyperplasia (CAH) is the most common cause of ambiguous genitalia in newborns. This paper is based upon review of the literature and personal experience. We focus upon the surgical anatomy, pre-operative evaluation, including imaging, mainly by transabdominal ultrasound, and upon the goals and the history of surgical reconstruction. The various surgical techniques are mentioned with a detailed description of our technique used in 52 patients. The timing and staging of the operation and the implications of prenatal therapy are discussed. In conclusion, we believe that infants with 46XX CAH can undergo one-stage feminizing genitoplasty very early in life with satisfactory cosmetic and functional results.

Adrenal Hyperplasia, Congenital↗
PubMed2001

Metal pollution as health indicator of lake ecosystems.

As part of a long-term monitoring study of the anthropogenic pollution of the Lake of Balaton (Hungary) the concentrations of toxic metals (Cd2+, Hg2+, Pb2+), as well as of bioelements (Cu2+ and Zn2+) were measured in the muscle, gill and liver of bream (Abramis brama L.) collected in the open water during the autumn of 1999, The highest Cd, Cu, Pb and Zn concentrations were detected in the gill and liver of fish, whereas the highest Hg concentrations were measured in the muscle. The maximum metal concentrations measured in the muscle of bream were generally below maximum permissible levels for human consumption established by the Hungarian Food Directorate. Depending on the sampling site, significantly higher Cd, Hg and Pb concentrations (p < 0.05) were detected in the muscle of fish samples collected from the Western basin, while no significant differences were observed for Cu and Zn. In the muscle and gill an increasing trend of heavy metal (Cd and Cu) load characterizes the individuals of the 2-4 calendar age group (p < 0.05), while for the older specimens the concentration of these elements decreased significantly (p < 0.05). Positive relationships on the whole age scale were found for Cd in the liver, for Pb in the gill, and for Hg both in the muscle and the liver of fish.

Animals↗
PubMed2000

Antiarrhythmic and electrophysiological effects of GYKI-16638, a novel N-(phenoxyalkyl)-N-phenylalkylamine, in rabbits.

The effect of N-[4-[2-N-methyl-N-[1-methyl-2-(2, 6-dimethylphenoxy)ethylamino]-ethyl]-phenyl]-methanesulfonamide. hydrochloride (GYKI-16638; 0.03 and 0.1 mg/kg, i.v.), a novel antiarrhythmic compound, was assessed and compared to that of D-sotalol (1 and 3 mg/kg, i.v.) on arrhythmias induced by 10 min of coronary artery occlusion and 10 min of reperfusion in anaesthetized rabbits. Also, its cellular electrophysiological effects were studied in rabbit right ventricular papillary muscle preparations and in rabbit single isolated ventricular myocytes. In anaesthetized rabbits, intravenous administration of 0.03 and 0.1 mg/kg GYKI-16638 and 1 and 3 mg/kg D-sotalol significantly increased survival during reperfusion (GYKI-16638: 82% and 77%, D-sotalol: 75% and 83% vs. 18% in controls, P<0.05, respectively). GYKI-16638 (0.1 mg/kg) significantly increased the number of animals that did not develop arrhythmias during reperfusion (46% vs. 0% in controls, P<0.05). In isolated rabbit right ventricular papillary muscle, 2 microM GYKI-16638, at 1 Hz stimulation frequency, lengthened the action potential duration at 50% and 90% repolarization (APD(50-90)) without influencing the resting membrane potential and action potential amplitude (APA). It decreased the maximal rate of depolarization (V(max)) in a use-dependent manner. This effect was statistically significant only at stimulation cycle lengths shorter than 700 ms. The offset kinetics of this V(max) block were relatively rapid, the corresponding time constant for recovery of V(max) was 328.2+/-65.0 ms. In patch-clamp experiments, performed in rabbit ventricular myocytes, 2 microM GYKI-16638 markedly depressed the rapid component of the delayed rectifier outward and moderately decreased the inward rectifier K(+) current without significantly altering the slow component of the delayed rectifier and transient outward K(+) currents. These results suggest that in rabbits, GYKI-16638 has an in vivo antiarrhythmic effect, comparable to that of D-sotalol, which can be best explained by its combined Class I/B and Class III actions.

Action Potentials↗
PubMed2000

[The role and value of urodynamics in the follow-up of children with surgical bladder augmentation and substitution].

The authors investigated postoperative capacity, compliance of the urinary bladder and urinary continence in children who underwent bladder augmentation and/or bladder substitution for various forms of urinary incontinence. In 20 children, bladder augmentation and/or bladder substitution procedures were performed because of urinary incontinence, upper urinary tract deterioration and/or failure of conservative treatment (oxybutynin, clean intermittent catheterization--ICC). In 2 patients, reaugmentation was necessary. Urodynamic studies were performed on a regular basis, preoperatively and postoperatively. Based on their experiences, the authors conclude that recognition of changes in bladder capacity and/or compliance and especially the risk of developing upper urinary tract changes is only possible by performing urodynamic studies regularly. Urodynamics is also essential in decision making processes regarding redo surgeries (reaugmentation, transient or permanent urinary diversion).

Adolescent↗
PubMed2000

Transabdominal pelvic sonography in the preoperative evaluation of patients with congenital adrenal hyperplasia.

PURPOSE: We assessed the clinical value of transabdominal pelvic sonography in the preoperative evaluation of patients with congenital adrenal hyperplasia (CAH) who required feminizing genitoplasty. METHODS: From 1987 to 1998, 31 patients with female pseudohermaphroditism due to CAH underwent feminizing genitoplasty. The median age of the patients was 9 months (range, 1-18 years). Radiologic evaluation performed before surgical reconstruction included retrograde genitography in the first 10 patients and sonographic examination in all 31 patients. Imaging was used to evaluate the anatomic positions and the length of the vagina, whether the junction of the vagina and the urogenital sinus occurred distal or proximal to the pelvic floor, and the presence of internal genitalia. RESULTS: Abdominal sonography identified internal female genitalia in all 31 patients, identified the anatomic shape and position of the vagina in 30 patients (97%), and confirmed the site of communication between the vagina and the urogenital sinus relative to the pelvic floor in 28 patients (90%). Sonographic findings were confirmed by intraoperative panendoscopy. Genitography was less useful than sonography, identifying the site of communication between the vagina and urogenital sinus in only 6 (60%) of 10 patients. CONCLUSIONS: In patients with CAH undergoing vaginal reconstruction, sonography provides adequate information about the anatomy of the vagina and urogenital sinus for surgical decision-making.

Adolescent↗
PubMed2000

An implant releasing the gonadotropin hormone-releasing hormone agonist histrelin maintains medical castration for up to 30 months in metastatic prostate cancer.

PURPOSE: The administration of gonadotropin hormone-releasing hormone agonists is well established for treating metastatic prostate cancer. In an ongoing study we evaluated the effect of a long acting implant that releases the gonadotropin hormone-releasing hormone agonist histrelin ([ImBzl]D-His6,Pro9-Net) in 15 patients with disseminated prostate cancer. MATERIALS AND METHODS: The 2.6 cm. implant releasing 60 microg. histrelin daily is inserted subcutaneously into the upper arm using local anesthesia. Of the patients 8 received 1 and the remainder received 2 implants. Treatment with the antiandrogen flutamide or cyproterone acetate began 2 weeks before implant insertion and continued for up to 12 weeks. Testosterone, luteinizing hormone (LH) and prostate specific antigen were determined monthly, and a metastatic evaluation was performed every 6 months. RESULTS: LH and testosterone increased after flutamide administration and decreased after implant insertion. By day 28 LH and testosterone were completely suppressed. LH and testosterone decreased immediately after cyproterone acetate administration. Prostate specific antigen began to decrease during antiandrogen therapy and decreased further after implant insertion. One patient requested implant removal after 1 year for personal reasons and 1 died of an unrelated cause 18 months after insertion. Escape was demonstrated in 4 cases at 5, 10, 12 and 19 months, although LH and testosterone remained suppressed. Duration of treatment in the remaining 9 patients was between 21 and 30 months. LH and testosterone remained completely suppressed and prostate specific antigen levels were in the normal range. The clinical and biochemical response was identical in those who received 1 or 2 implants. At 12 months 8 patients were challenged at intermittent intervals for up to 24 months with a bolus of 100 microg. gonadotropin hormone-releasing hormone followed by 2 weeks of flutamide. The response was compared with that in untreated controls recently diagnosed with prostate cancer. Unlike controls there was complete LH suppression in the 8 challenged patients. CONCLUSIONS: A histrelin implant suppresses LH and testosterone in prostate cancer for up to 30 months. This finding represents a significant improvement over existing preparations, which must be administered at 1 to 3-month intervals.

Aged↗
PubMed2000

Ethnic and racial differences in prostate cancer incidence and mortality.

Prostate cancer (CaP) incidence and mortality vary strikingly among ethnic, racial, and national groups. There is evidence that genetic, environmental, and social factors jointly-and often in combination-contribute to the observed differences in various populations. Noteworthy is the high rate of both CaP incidence and mortality among African Americans. Changes in the epidemiology of CaP since the advent of prostate specific antigen testing suggest that improved access to screening and treatment may serve to reduce somewhat the differences between the white and African-American populations. However, because the causes of these differences are likely to be multifactorial, a variety of strategies addressing the range of causes will be necessary to reduce the excess African-American mortality from this disease.

Asian↗
PubMed1999

Does early detection of ureteropelvic junction obstruction improve surgical outcome in terms of renal function?

PURPOSE: Prenatal ultrasound leads to the early detection of hydronephrosis. When followed by the early diagnosis of ureteropelvic junction obstruction surgical treatment, if indicated, is associated with minimal morbidity. We attempt to prove the benefits of this therapeutical approach from the point of view of renal function. MATERIALS AND METHODS: From 1979 to 1997, 452 patients with ureteropelvic junction obstruction underwent dismembered pyeloplasty. Of these patients 113 with comparable data were retrospectively evaluated. Patients were divided into group 1-50 who presented with prenatal hydronephrosis and group 2-63 with neonatal hydronephrosis who were lost to followup and who then presented with symptoms leading to the diagnosis of ureteropelvic junction obstruction. In each group the diagnostic criteria and indications for surgery were identical based on symptomatology, ultrasound and renal scan. Patients with bilateral disease, solitary kidney or vesicoureteral reflux were excluded from study. In groups 1 and 2 median patient age at surgery was 11 months and 5 years, and average postoperative followup was 4.2 and 3.2 years, respectively. RESULTS: In 41 of the 50 group 1 and 60 of the 63 group 2 patients hydronephrosis was severe and the renal pelvis was more than 3 cm. wide. Poor relative renal function (less than 30%) was significantly more pronounced in group 2 than in group 1 (56 of 63 patients or 89% versus 6 of 50 or 12%, p <0.05). In all 113 patients postoperative followup ultrasound and renal scan revealed significant improvement in hydronephrosis and washout curve pattern. There was a significant difference in the 2 groups in regard to renal function improvement postoperatively (66% of group 1 versus 16% of group 2 patients, p <0.05). CONCLUSIONS: We believe that patients who undergo prenatal imaging and are diagnosed early with ureteropelvic junction obstruction should be carefully and meticulously followed. Special efforts should be made to ensure that patients are not lost to followup. After any sign of deterioration develops early surgery is indicated. According to our data operative treatment results in improved renal function.

Child, Preschool↗
PubMed1999

Inadequate ischaemia-selectivity limits the antiarrhythmic efficacy of mibefradil during regional ischaemia and reperfusion in the rat isolated perfused heart.

1. Mibefradil was compared with (+/-)-verapamil for effects on ischaemia- and reperfusion-induced ventricular fibrillation (VF), and the role of ischaemia-selective L-channel block was examined. Langendorff perfused rat hearts (n=12/group) were used. 2. Neither drug at up to 100 nM reduced the incidence of VF during 30 min regional ischaemia. 300 and 600 nM (+/-)-verapamil abolished VF (P<0. 05); mibefradil was effective only at 600 nM (P<0.05). Reperfusion-induced VF incidence was reduced only by 600 nM (+/-)-verapamil (P<0.05). Both drugs at >/=100 nM increased coronary flow (P<0.05) with a similar potency and maximum effectiveness. 3. In separate hearts perfused with Krebs' solution containing 3 mM K+ (the same as that used for arrhythmia studies) neither drug at up to 600 nM affected ventricular contractility. With K+ raised to 6 mM, (+/-)-verapamil >/=30 nM reduced developed pressure (P<0.05); mibefradil did so only at 600 nM (P<0.05). With K+ raised to 10 mM the effects of (+/-)-verapamil were further increased (P<0.05) and mibefradil became active at >/=100 nM (P<0.05). Likewise both drugs impaired diastolic relaxation, with raised K+ exacerbating the effects and (+/-)-verapamil being more potent and its effects more greatly exacerbated by K+. In contrast, when K+ was normal (3 mM), coronary flow was increased by each drug at >/=30 nM (P<0.05) indicating a marked vascular : myocardial selectivity. 4. In conclusion, mibefradil differed from (+/-)-verapamil in its myocardial effects only in terms of its lower potency. As mibefradil is the more potent T-channel blocker, the T-channel is unlikely to represent the molecular target for these effects. The K+ elevations that occur in the ischaemic milieu determine the ability of both drugs to block myocardial L-channels; this is sufficient to account for the drugs' actions on VF. Neither drug possesses sufficient selectivity for ischaemic myocardium versus blood vessels to permit efficacy (VF suppression without marked vasodilatation) and so inappropriate hypotension is likely to preclude the safe use of mibefradil (or similar analogue) in VF suppression, and explains the lack of clinical effectiveness of (+/-)-verapamil.

Animals↗
PubMed1999

Laser prostatectomy. Long-term follow-up of 303 patients.

OBJECTIVE: This retrospective study was undertaken to evaluate results and complications in 303 patients with symptomatic bladder outlet obstruction due to benign prostatic hyperplasia (BPH) who underwent laser prostatectomy focusing on the long-term follow-up, 57 patients had a follow-up of more than 3 years. MATERIALS AND METHODS: A total of 303 patients were treated with the neodymium:YAG laser system for 1993 to 1997, of whom 57 patients were followed up for at least 3 years. All of the patients have been evaluated after 3 months, 6 months and 2 years. 57 patients were evaluated after 3 years. Pre- and postoperative American Urological Association (AUA) symptom score, uroflowmetry (UF), and immediate and long-term complications were assessed. RESULTS: The mean AUA symptom scores of 303 patients decreased over the 24 months follow-up from 16.9 to 7.6. In 57 patients after 36 months the mean AUA symptom score was 7.1. The mean maximal UF increased over the 24 months from 9 to 14.1 cm3/s in 303 patients. In 57 patients at 3 years the mean UF was 13. 9 cm3/s. The overall complications of 303 patients included two perforations of the bladder wall and two perforations of the prostatic capsule. Six (1.9%) patients had postoperative febrile UTI and 28 (9.2%) patients had acute urinary retention after catheter removal. Early bleeding occurred in 3 (0.9%) patients, late bleeding in 8 (2.4%), 4 (1.2%) had urethral stricture, and 1 had stricture of the bladder neck. The overall reoperation rate for symptomatic residual tissue was 1.9% (6 patients). CONCLUSION: Neodymium:YAG laser ablation of prostate represents an efficacious surgical intervention for symptomatic bladder outlet obstruction due to BPH with minimal associated morbidity.

Aged↗
PubMed1999

Sonographic diagnosis of ureteral tumors.

We present our experience with transabdominal ultrasonographic diagnosis of ureteral tumors. During the years 1989 to 1998, 16 patients were diagnosed as having ureteral tumors. These patients were referred for sonographic examination for evaluation of hematuria (seven patients) or flank pain (four patients) or for follow-up screening in patients who were asymptomatic but at high risk for transitional cell carcinoma because of known past bladder tumor (five patients). Ten of these patients underwent intravenous urography examination, three patients had retrograde pyelography, and 11 patients underwent CT scanning. Ultrasonography revealed the ureteral tumors in all 16 patients, which appeared as hypoechoic intraluminal soft tissue. Three tumors were localized in the upper ureter, four in the middle ureter, and nine in the distal ureter. The degree of ureterohydronephrosis was minimal (two cases), mild (five cases), moderate (eight cases), or severe (one case). Eleven tumors caused local widening of the ureteral diameter. On intravenous urography, four patients had a nonfunctioning kidney, three patients had unexplained ureterohydronephrosis, and three patients showed ureteral filling defects, of which only two had irregular contours. On retrograde pyelography, two patients had filling defects (one of which with smooth margins), and one had a truncated ureter. On CT the tumor was clearly demonstrated in only seven patients. We found that ultrasonography can be a useful diagnostic tool in the workup of ureteral tumors.

Abdominal Pain↗
PubMed1999

Characteristics influencing changes in aerobic performance of children aged 7-9.

Interpretation of the actual level of aerobic endurance in a growing child is difficult. Endurance capacity per se is influenced by a number of factors, e.g. by genetic endowment, developmental rate, body composition and habitual physical activity. The respective effects of these factors cannot be distinctly separated from one another, so their particular role is not clearly definable in the various age periods. The aim of our investigation was to define the actual level of aerobic endurance performance in children aged 7-9, and to analyse the relevant factors that may affect this kind of performance according to the different level of sport activities. Two primary school classes (N=42) were selected for the experiment. Both groups had physical education classes every day (five times a week). One group (AG, N=31) consisted of children taking part in regular sport courses at least twice a week (e.g. basket ball, karate, triathlon swimming and gymnastics), as well, the other group (NAG, N=11) served as comparison group. Aerobic performance was estimated by measuring cardiorespiratory response during a Jaeger treadmill run using a "vita maxima" (all-out) testing protocol. The subjects were measured in the Laboratory for Spiroergometry of the Hungarian University of Physical Education twice, in 1997 and 1998. Body composition was assessed by the Drinkwater-Ross [4] body mass fractionation technique. Robustness of the body was described by using the plastic index (PLX) of Conrad's growth type [2], morphological age (MORF AGE) was estimated by using the method of Mészáros and Mohácsi [5]. Exercise performance was studied in the laboratory by using a Jaeger 6000 LE model treadmill and a Jaeger mu-DATASPIR model gas analyser. The functional status of the subjects' cardiopulmonary system was estimated by spiroergometric parameters and total mechanical work (WORK). The AG group had a better endurance performance in 1998 than that of non-athletic group. A factor analytic study (principal component method) of the employed variables revealed that the higher level of endurance fitness in the athletic group was not only affected by growth in size, but also by an increased level of cardiorespiratory performance capacity.

Aerobiosis↗
PubMed1998

Comparison of the antiarrhythmic and the proarrhythmic effect of almokalant in anaesthetised rabbits.

In this study the antiarrhythmic and the proarrhythmic activities of almokalant, a selective class III antiarrhythmic agent, were compared. The antiarrhythmic effect of the drug was tested in pentobarbital-anaesthetised rabbits. Arrhythmia was evoked by occluding and releasing the left circumflex coronary artery. Almokalant in a dose of 250 nmol/kg i.v., significantly decreased the incidence of reperfusion induced ventricular fibrillation (21% vs. 75% in the control group) and increased the proportion of surviving animals during reperfusion (86% vs. 42%). The proarrhythmic effect of almokalant was examined during alpha1-adrenoceptor stimulation in chloralose-anaesthetised rabbits. Almokalant (75 nmol/kg per min) triggered torsade de pointes arrhythmias in 8 animals out of 11. The dose of almokalant (mean+/-S.E.M.) required to produce this effect was 1181+/-519 nmol/kg. It is concluded that, although almokalant is an effective antiarrhythmic agent against ischaemia-reperfusion induced arrhythmias, it has marked proarrhythmic activity during alpha1-adrenoceptor stimulation.

Adrenergic alpha-Agonists↗
PubMed1998

Trends in poorly differentiated prostate cancer 1973 to 1994: observations from the Surveillance, Epidemiology and End Results database.

PURPOSE: Using the Surveillance, Epidemiology and End Results Program, we evaluated the changing demographics of poorly differentiated prostate cancer since early detection measures, such as serum prostate specific antigen screening, were introduced into clinical practice in the United States. MATERIALS AND METHODS: Trends between 1973 and 1994 in the proportion, stage and treatment of poorly differentiated tumors (International Classification of Diseases [ICD]-O code 3, Gleason score 8, 9, 10) were assessed, and multivariate Cox proportional hazards models were used to identify independent correlates of disease specific survival. RESULTS: The number of ICD-O grade 3 tumors increased during the study period, although these comprised a decreased proportion of all diagnosed cases (24.4% of 29,588 in 1980 to 1984 versus 21.4% of 81,932 in 1990 to 1994, chi-square p < 0.001). ICD-O grade 3 tumors were less often metastatic in 1990 to 1994 compared to 1980 to 1984 (17.4% versus 33.1%, chi-square p < 0.0001) and more often treated with radical prostatectomy or radiotherapy in 1990 to 1994 compared to 1983 to 1984 (37.5 versus 15.6%, chi-square p < 0.001). Although treatment group (radiotherapy versus radical prostatectomy) among patients with clinically confined tumors was an independent correlate of disease specific survival (hazard ratio 2.3, 1983 to 1984 and 3.3, 1990 to 1994), one must recognize potential selection biases inherent to this nonrandomized tumor registry study. The observed 12-year actuarial disease specific survival rates were 67.6% for radical prostatectomy and 46.3% for radiotherapy. CONCLUSIONS: In the present era ICD-O grade 3 tumors are being detected in increasing number, are less likely to be metastatic at presentation and are more likely to be treated definitively with radical prostatectomy or radiotherapy. Disease specific survival rates observed with radical prostatectomy and radiotherapy in patients with clinically confined tumors support current efforts to detect and treat these highly aggressive tumors while clinically localized.

Humans↗