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K Boos

Publications and source records attributed to K Boos.

11 recordsLinked to original sources
PubMed2000

Pivotal role of reactive oxygen species as intracellular mediators of hyperthermia-induced apoptosis.

The effects of cellular antioxidant capacity on hyperthermia (HT)-induced apoptosis and production of antiapoptotic heat shock proteins (HSPs) were investigated in HL-60 cells and in HL-60AR cells that are characterized by an elevated endogenous catalase activity. Exposure of both cell lines to 43 degrees C for 1 h initiated apoptosis. Apoptosis peaked at 3-6 h after heat exposure in the HL-60 cells. Whereas HL-60AR cells were partially protected against HT-induced apoptosis at these early time points, maximal levels of apoptosis were detected later, i.e. 12-18 h after heat exposure. This differential induction of apoptosis was directly correlated to the induction of the antiapoptotic HSP27 and HSP70. In particular, in the HL-60 cells HSP27 was significantly induced at 12-18 h after exposure to 43 degrees C when apoptosis dropped. In contrast, coinciding with the late onset of apoptosis in HL-60AR cells at that time HL-60AR cells lacked a similar HSP response. In line with the higher antioxidant capacity HL-60AR cells accumulated reactive oxygen species to a lesser degree than HL-60 cells after heat treatment. Protection from HT-induced apoptosis as well as diminished heat-induced HSP27 expression was also observed after cotreatment of HL-60 cells with 43 degrees C and catalase but not with superoxide dismutase. These data emphasize the pivotal role of reactive oxygen species for HT induced pro- and antiapoptotic pathways.

Apoptosis↗
PubMed2000

Ventricular flutter in a neonate--severe electrolyte imbalance caused by urinary tract infection in the presence of urinary tract malformation.

Male infants under the age of 3 months presenting with pyelonephritis in the presence of urinary tract malformation (UTM) are prone to transient pseudohypoaldosteronism. This may resemble congenital adrenal hyperplasia (CAH). Hyponatremia, hyperkalemia, dehydration, and metabolic acidosis are the primary findings that permit the diagnosis of CAH. We report a case of transient pseudohypoaldosteronism resulting from pyelonephritis and vesicouretric reflux. The 17-day-old boy presented with a salt-losing episode simulating adrenal insufficiency. An initial diagnosis of CAH was made. The severe metabolic imbalance resulted in ventricular flutter that resolved after correction of the metabolic acidosis and the electrolyte and volume depletion. Early diagnosis is essential because both conditions are potentially fatal and treatment differs significantly. Differential diagnosis may be achieved by urinalysis and abdominal ultrasound scan.

Acidosis↗
PubMed1999

Imaging the urethral sphincter with three-dimensional ultrasound.

OBJECTIVE: To image the striated urethral sphincter (rhabdosphincter) using three-dimensional ultrasound and to compare its size in women with genuine stress incontinence and continent controls. METHODS: Women with no previous continence or prolapse surgery had transvaginal sonography using a 7.5-MHz mechanical sector endoprobe with real-time and three-dimensional facilities. Three perpendicular planes were displayed simultaneously on the screen. Manipulation of the stored images allowed detailed morphologic assessment of the urethra at different levels using several parallel cross-sectional planes along its length. The length, thickness, and volume of the rhabdosphincter were measured. RESULTS: Forty-six women with genuine stress incontinence (27-73 years, mean 48) and 48 continent controls (23-76 years, mean 49) were studied. In the transverse plane, the inner part of the urethra, which consists of urothelium and smooth muscle, appeared hyperechogenic compared with the outer hypoechogenic ring of striated muscle. The two groups studied were not different in age and parity. Women with genuine stress incontinence, compared with continent controls, had a significantly shorter (mean +/- standard deviation 16.9 +/- 1.9 mm compared with 19.2 +/- 3.6 mm; P = .001), thinner (2.1 +/- 0.5 mm compared with 2.5 +/- 0.4 mm; P < .001), and smaller volume (0.8 +/- 0.2 mL compared with 1.2 +/- 0.2 mm; P < .001) of the striated urethral sphincter. There was a close correlation between the urethral sphincter volume and the degree of incontinence assessed on videocystourethrography (r = -.65, P < .001). CONCLUSION: Three-dimensional ultrasound allowed examination of the female urethra in planes that could not be visualized by conventional sonography. The rhabdosphincter had a smaller volume in women with genuine stress incontinence than in continent women.

Adult↗
PubMed1999

Colposuspension after previous failed incontinence surgery: a prospective observational study.

OBJECTIVE: To evaluate the outcome of colposuspension for genuine stress incontinence in women who had previously undergone bladder neck surgery. DESIGN: Prospective observational study. SETTING: Tertiary referral urogynaecology unit. PARTICIPANTS: Fifty-two consecutive women with recurrent genuine stress incontinence operated on by one surgeon. MAIN OUTCOME MEASURES: Subjective and objective cure of stress incontinence. Complications of surgery. RESULTS: The mean age of the women was 51 years (range 28-72) and weight 72.7 kg (range 53-112). Sixty-five continence procedures had been performed previously, with 13 women (25%) having had more than one operation. Nine months post-operatively the subjective cure rate was 80% and objective cure rate 78%. Intraoperative complications were few but included two bladder injuries and one rectus muscle tear which required repair. Seven women (13%) developed voiding difficulties which required clean intermittent self-catheterisation, but only one needed to continue this for six months. None of the women developed detrusor instability. CONCLUSIONS: In this setting colposuspension after previous bladder neck surgery offers a high rate of success. However, long term follow up is needed to see if this effect is maintained.

Adult↗
PubMed1999

Lower urinary tract symptoms and their impact on women with anorexia nervosa.

Anorexia nervosa is a condition which is associated with extremely low body weight and endocrine problems including persistent anovulation and a hypo-oestrogenic state. As the lower urinary tract is oestrogen sensitive, it is possible that women suffering from anorexia nervosa may experience similar distressing urinary problems. Of 29 anorexic women assessed, the majority had significant irritative urinary symptoms of which frequency, urgency and nocturia were the most common. These symptoms also had an unfavorable impact on their quality of life.

Adolescent↗
PubMed1998

Videocystourethrography with a ring pessary in situ. A clinically useful preoperative investigation for continent women with urogenital prolapse?

The aim of the study was to evaluate the use of a vaginal pessary in the detection of genuine stress incontinence (GSI) in women with urogenital prolapse undergoing urodynamic investigation. Continent women with urogenital prolapse, with or without associated urinary symptoms, were studied. All underwent videocystourethrography using a standardized protocol. None had evidence of incontinence on provocative testing in the upright position. A well-fitting vaginal ring pessary was inserted to reduce the prolapse and mimic a vaginal repair. The provocative tests were then repeated while the bladder was screened. Seventy women with a mean age 59.0 years (range 34-83) were recruited over a 21-month period: 15 women complained of prolapse alone and 55 had concurrent urinary symptoms; 19 women (27%) developed GSI only following the insertion of a vaginal pessary. The women who became incontinent were significantly older (mean age 63.9 years) than those who remained continent (mean age 56.8 years) (P < 0.020). The use of a vaginal pessary increases the detection rate of GSI in continent women with urogenital prolapse undergoing videocystourethrography. These findings are important because women with prolapse and coexisting incontinence should be offered a continence procedure rather than a simple vaginal repair.

Female↗
PubMed1996

[Peridural catheter for postoperative long-term analgesia in children].

INTRODUCTION: Continuous epidural anaesthesia is a well established procedure for postoperative analgesia as well as sympathicolysis in adult patients. It is, however, much less frequently reported in infants and children. MATERIALS AND METHODS: From October 1991 to November 1994 65 infants, children and adolescents aged 4 weeks to 19 years, body weight 3.9 kg to 79 kg, received 77 epidural catheters for postoperative analgesia. 54 catheters were inserted via the caudal approach either with (n = 19) or without (n = 35) subcutaneous tunnelling. 23 catheters were placed via a low midline lumbar epidural puncture either through interspace L5/S1 or L4/L5. The local anaesthetic of choice in this study was bupivacaine 0.125% without adrenaline infused continuously via a constant-flow infusion pump. 20 patients received additional boluses of morphine and in 3 patients clonidine was added. The catheters were left in place for an average of 84.5 h. After removal the catheter-tip was submitted for bacteriological examination. The results of 64 specimens were available. RESULTS: For satisfactory analgesia an average of 0.18 mg x kg-1 x h-1 bupivacaine 0.125% had to be administered via the lumbar route, while the mean dose for caudal catheters was 0.3 mg x kg-1 x h-1. Intestinal peristalsis re-occurred within 33 h after surgery. The first stool was passed within 48 h. Of the 64 catheters which were microbiologically examined, 15 exhibited bacterial colonisation with a statistically significant difference between those subcutaneously tunnelled and those inserted directly (p < 0.05). There were, however, no signs of local or systemic infection. CONCLUSIONS: The results of continuous epidural anaesthesia and sympathicolysis in infants and children are encouraging. This technique is readily employable and complications seem to be rare. Satisfactory analgesia and sympathicolysis were achieved. Based on the results of our bacteriological studies we recommend that caudal catheters are tunnelled subcutaneously in cranio-lateral direction.

Adolescent↗