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A Ek

Publications and source records attributed to A Ek.

At least 19 recordsLinked to original sources
PubMed1995

The uptake of ascorbic acid into human umbilical vein endothelial cells and its effect on oxidant insult.

Intracellular reduced ascorbate (AA) levels in confluent cultures of human umbilical vein endothelial (HUVE) cells, grown under conventional conditions, were shown to be very low, ranging between undetectable, < 0.1 nmol/mg protein, and 0.3 nmol/mg protein. Reduced ascorbate was accumulated into the endothelial cells from M199 culture medium in time- and concentration-dependent manners, and was saturated at medium concentrations related to the normal plasma concentrations of the antioxidant (i.e. between 50 microM and 100 microM). Cells derived from different individuals demonstrated considerable inter-individual variation in these AA uptake parameters. The uptake of AA was sensitive to temperature and the presence of the structural analogue isoascorbate in the medium, indicating the involvement of an active transport mechanism. A role for the glucose transporter is, however, not indicated, as AA uptake was not sensitive to phloretin, an inhibitor of the cellular glucose transporter, nor greatly enhanced by depletion of glucose from the medium. Incubation of HUVE cells with dehydroascorbate (DHAA) caused a dose-dependent, but transient increase in intracellular AA. This indicates that HUVE cells are both competent in the uptake and intracellular reduction of oxidised ascorbate, and may resecrete AA into the medium. Indeed, reduced ascorbate in the medium was shown to be preferentially maintained in the presence of cells. The uptake of AA was not sensitive to the presence of DHAA in the medium, perhaps indicating different transporters for reduced and oxidised forms of ascorbate in these human cells. Pre-loading HUVE cells with AA was shown to protect control cells only weakly from the acute, sub-lethal toxicity of H2O2 generated by xanthine oxidase (1 U/mL or 10 U/mL). Protection was optimal at intracellular levels of 3-4 nmol AA/mg protein, with higher concentrations lacking a protective effect. Additionally, the presence of the iron chelator, desferoxamine, significantly protected GSH-depleted HUVE cells only in response to the peroxide, but did not potentiate the protective action of intracellular AA in either control or GSH-depleted cells. This indicates that ascorbate-driven redox-cycling of the Fe2+/Fe3+ does not hamper the intracellular protective function of ascorbate during hydrogen peroxide-derived oxidative stress. These results are discussed in terms of the central role of endothelial cells in the distribution of AA to the tissues of the body, the use of the HUVE cell system for model studies of the toxicity of oxidants in the human endothelium, and the balance between the antioxidant and pro-oxidant actions of AA.

Ascorbic Acid↗
PubMed1989

Vectorcardiographic bites. A method for detection and quantification applied on a normal material.

Vectorcardiographic bites as an expression of small fibrotic or necrotic areas in the myocardium have been discussed for many years. Distinct definitions of bites and normal limits for bites have, however, not been established. Therefore, an algorithm for computer detection and quantification of bites is presented. To find a bite, sectors of the QRS loop rotating opposite the way of the main part of the loop (eg, a clockwise-rotating sector in an otherwise counterclockwise-rotated loop) are detected. The bite is then delineated, using an iterative procedure. Finally the amplitude, duration, and area of the bite are calculated. The method for detection and quantification was applied on a well-defined normal material to obtain normal limits for bites. The commonly used criterion for an abnormal bite (amplitude greater than or equal to 0.1 mV and duration greater than or equal to 10 msec in the horizontal or sagittal plane) results in a specificity of only 87%. A specificity of 95% is yielded with the criterion of bite amplitude greater than 0.15 mV in the horizontal or sagittal plane.

Adult↗
PubMed1986

Contelle: pelvic floor stimulator for female stress-urge incontinence. A multicenter study.

The clinical efficacy of a new device for treatment of female incontinence was studied in a multicenter trial. The device consists of an inflatable electrode carrier and an external stimulator unit. Forty women were treated: 10 had primary or recurrent genuine stress incontinence, 15 had urge incontinence due to idiopathic detrusor instability, not responding to drug treatment, and 15 had stress incontinence combined with detrusor instability. Twenty-five patients were improved by the treatment. Another 8 reported an excellent result of treatment and remained free of symptoms for more than six months after withdrawal of the treatment. The results were more favorable in patients with bladder hyperactivity than in genuine stress incontinence. The patients' general ratings of treatment efficacy correlated well with their recordings of urinary frequency and consumption of incontinence pads. The functional bladder capacity increased in improved patients, but normalization of urodynamic parameters was no prerequisite for clinical improvement. We found intravaginal electrical stimulation to be a valuable alternative to medical and surgical intervention in patients with detrusor instability.

Adult↗
PubMed1986

Huge bladder carcinoma successfully treated with hydrostatic pressure technique. A case report.

A 64-year-old man presented with acute urinary retention and anasarca due to noninvasive multiple papillary transitional cell carcinoma filling the whole bladder cavity and obstructing both ureters. He was treated with hydrostatic pressure distension. A dramatic response occurred, with complete disappearance of the tumour within one month of the treatment.

Carcinoma, Transitional Cell↗
PubMed1985

Ejaculation and sexual function after endoscopic bladder neck incision.

Endoscopic incision of the bladder neck, performed to relieve outflow obstruction, was evaluated as regards effects on ejaculation and orgasm in 61 men (mean age 48 years) by analyses of seminal fluid and a questionnaire. Relief of obstruction was confirmed by post-operative normalisation of urinary flow. In 47 cases there was unchanged antegrade ejaculation, while reduced semen volume was reported by 11 men and retrograde ejaculation by only 3. The quality of orgasm and sexual satisfaction were not permanently changed by the operation. Post-operative analysis of seminal fluid was performed in 27 patients, with normal results in 26. In 16 men who provided specimens both before and after bladder neck incision, no consistent change was found in the semen. An incision completely splitting the bladder neck but not extending distal to the verumontanum will relieve outlet obstruction. Maintenance of antegrade ejaculation can be expected in most patients undergoing this operation.

Adult↗
PubMed1984

Occlusion of renal arterial tumor supply with absolute ethanol. Experience with 20 cases.

Absolute ethanol was used for renal ablation in 20 patients with carcinoma of the kidney. The procedure was followed by nephrectomy in 6 patients without metastases, all of whom are alive without evidence of recurrence 4 to 20 months after treatment. Fourteen patients with metastatic or locally advanced disease were embolized to palliate pain or hematuria without subsequent nephrectomy. Of these only 2 are alive, 4 and 18 months following the procedure. The technique for ethanol embolization is described and the use of occluding balloon catheters is recommended. No complications were encountered and the 'postembolization syndrome' was less marked as compared with a previous material of equal size where other methods of renal artery occlusion were employed. Microscopic examination in 10 of the infarcted kidneys showed extensive tumor necroses, sometimes with no evidence of viable tumor cells at all. Natural killer cell activity was determined before and 48 hours after renal artery occlusion in 7 patients, showing somewhat increased activity in 4. It is concluded that absolute ethanol is a safe, effective and easily administered agent for the infarction of renal tumors.

Adenocarcinoma↗
PubMed1984

Intravesical adriamycin therapy in carcinoma in situ of the urinary bladder.

Intravesical Adriamycin treatment was given to 22 patients with carcinoma in situ of the urinary bladder. The treatment schedule consisted of monthly Adriamycin instillations in a dose related to bladder capacity. Endoscopic inspection with multiple bladder biopsies and cytoanalysis of urine was performed after every third instillation. In two patients there was lasting disappearance of the carcinoma in situ. Another 10 patients possibly had a beneficial effect of the treatment. The remaining 10 patients showed persistent malignancy and in 6 of these, progression of carcinoma in situ during Adriamycin treatment necessitated cystectomy or radiotherapy. The histologic and cytologic findings showed distinct variability in most patients, with atypia or even absence of malignant cells often followed by recurrence. Adriamycin was discontinued in four cases because of severe cystitis, and in one case because of an anaphylactoid reaction following instillation of the drug.

Aged↗
PubMed1983

Effects of prazosin in patients with benign prostatic obstruction.

Prazosin, a selective alpha-1-adrenoceptor blocker, was used in a double-blind crossover study in 20 men with benign prostatic obstruction. Maximum and average flow rates increased, and residual volume and obstructive symptoms were reduced. Voiding pressure parameters, bladder capacity and irritative symptoms did not change significantly. No side effects were noted. We conclude that prazosin seems to be an effective therapeutic alternative in patients with benign prostatic obstruction.

Aged↗
PubMed1983

Nocturnal penile rigidity measured by the snap-gauge band.

Nocturnal penile tumescence is used commonly to evaluate erectile dysfunction. However, this test is not equivalent to erection since it measures circumferential change only rather than the crucial variable of penile rigidity. We present a new concept in the measurement of penile rigidity--the capability of a patient during sleep to break a band furnished with pre-set snap-gauges with different release-force constants applied around the penile shaft. The snap-gauge band was tested simultaneously with the recording of nocturnal penile tumescence measuring penile rigidity rather than tumescence.

Adult↗
PubMed1983

History of cystometry.

Looking back on the changes in the conceptualization of micturition and the development of cystometry, it is reasonable to arrive at several conclusions. Considering their poor technical equipment, Budge's and Goltz's neurophysiologic observations in the 19th century were impressive. The pontine center for micturition, found by Budge, was later confirmed, by Barrington, to have a facilitating and coordinating function. Goltz's demonstration that micturition could be partially accomplished by a spinal reflex was unfortunately given too little attention by clinicians practicing cystometry in the beginning of this century. Dubois' careful pioneering investigations of bladder pressure, and Mosso and Pellacani's studies in bladder motility were outstanding. From Born's and Genouville's contributions, continuously recordable filling cystometry was developed as early as the end of the last century. However, due to a fixation on "bladder tone" and the concept of "crossed innervation" by succeeding investigators, development of cystometry was at a standstill for almost forty years before gradually attaining its modern interpretation. Compared to our century, it is striking how carefully all investigators from the 19th century cited each other and knew about each other's work. This was possible, in spite of poor communication, because of the small number of investigators involved in studies of bladder function. Although cystometry today is quite informative in many cases, two main points, the presence of detrusor contraction reflex and the patient's capacity to suppress its occurrence, are still highly dependent on the technique used and the subject's cooperation. The more complicated urodynamic investigations flourishing during the last fifteen years have been met with the same uncertainty as the preceding ones since they are partially or completely dependent on patient compliance. Frequently, findings in the laboratory do not relate to the clinical situation. Hopefully, future development of monitoring of bladder-urethral function and the use of neurophysiologic electrodiagnostic methods will reduce these difficulties. The authors believe that modern cystometry began in the 1950s, and that discussion of this period and up to the present is more appropriately the subject of a review on modern methodologies. Further, it is difficult to place modern technology and investigators in historical perspective when events are evolving.

Egypt↗
PubMed1981

Estrogen receptors in the human female lower uninary tract.

Cytosolic and nuclear fractions prepared from the urethra, urinary bladder, and trigonum of the bladder obtained at urethrocystectomy from four female patients were analyzed for the presence of estrogen receptors. High-affinity estradiol receptors (KD 0.7 x 10(-9)M) could be detected in both cytosolic and nuclear fractions of the urethra from all four patients. Estradiol receptors could be detected in only the nuclear fractions of the urinary bladder in two of the four preparations. In the trigonum, cytosolic and nuclear receptors could be measured in one and three preparations, respectively. The receptor concentrations in both trigonum and the bladder were lower than those in the urethra. By providing experimental evidence for the presence of estradiol receptors in the lower uninary tract, the present data advance the case for estradiol therapy in incontinent patients.

Adult↗
PubMed1981

Effects of prazosin on isolated human urethra and in patients with lower motor neurons lesions.

In isolated human urethra, prazosin competitively inhibited contractions induced by noradrenaline, but had no effect on contractions elicited by potassium (127 mM), suggesting an action solely on alpha-adrenoceptors. Seven patients with lower motor neuron lesions and micturition disturbances were treated with 2 mg of prazosin twice daily. Five were investigated by simultaneous urethrocystometry before and during treatment. Prazosin reduced the intraurethral pressure, the intravesical pressure during bladder filling, and autonomous bladder waves. Voiding and incontinence improved in five patients. In one, voiding was facilitated, but continence deteriorated, and in one, no clinical effects were observed. In all patients, residual urine decreased. There were no side effects, except one case of nasal congestion. It is concluded that prazosin effectively reduces alpha-adrenoceptor mediated hyperactivity in the smooth muscle of the lower urinary tract, and that it may be an effective treatment of micturition disturbances in patients with lower motor neuron lesions.

Adolescent↗
PubMed1980

Intracavitary Epodyl for multiple non-invasive, highly differentiated bladder tumours.

Multiple, recurrent cancer of the bladder grade I-II (WHO), stage T1 (UICC) was treated with regular intravesical instillation of ethoglucid (Epodyl) in 39 patients. In ten of them cystitis necessitated withdrawal of the treatment. The therapeutic schedule could be followed in 29 cases, with eradication of the tumours in 27. Nine patients who continued the treatment on a prophylactic basis were still recurrence-free after 18-60 (mean 37) months. Myelosuppression did not occur, but cystitis was a serious problem that frequently jeopardized therapy.

Aged↗