Biomedical subjects

O Jonsson

Publications and source records attributed to O Jonsson.

At least 19 recordsLinked to original sources

PubMed2006

Continent cutaneous urinary diversion in patients with spinal cord injury.

STUDY DESIGN: Retrospective study. OBJECTIVE: To examine the functional results and effect on quality of life of continent cutaneous urinary diversion in spinal cord injured patients. SETTING: Department of Urology, Sahlgrenska University Hospital, Göteborg, Sweden. SUBJECTS: A total of 10 patients with spinal cord injury (SCI). METHOD: The patients were operated on with an ileal reservoir (Kock reservoir or T-pouch), Cr-EDTA clearance was determined preoperatively and at follow-up. The patients answered a questionnaire concerning reservoir function, various activities and quality of life. The patient charts were reviewed. RESULTS: One patient died of pulmonary embolism 3 years after surgery. Two patients were reoperated on for reservoir perforation. All patients were satisfied/very satisfied with their reservoirs. Half of them reported improved ability to perform various activities. Eight out of nine patients reported improved quality of life. CONCLUSION: For a selected group of patients with SCI, continent cutaneous urinary diversion provides successful outcome with improved quality of life.

Activities of Daily Living↗

PubMed2005

Recurrent vesical calculi, hypercalciuria, and biochemical evidence of increased bone resorption in an adult male with paraplegia due to spinal cord injury: is there a role for intermittent oral disodium etidronate therapy for prevention of calcium phosphate bladder stones?

STUDY DESIGN: Clinical case report with comments by colleagues from Sweden, Poland, Spain, Brazil, Japan, Belgium and Switzerland. OBJECTIVES: To discuss the role of disodium etidronate therapy for prevention of calcium phosphate vesical calculi in persons with spinal cord injury, who have hypercalciuria and biochemical evidence of increased bone resorption. SETTING: Regional Spinal Injuries Centre, Southport, UK. METHODS: A 21-year-old male sustained paraplegia (T-10; ASIA scale: A) in a road traffic accident in June 2001. He had an indwelling urethral catheter until the end of August 2001, when he started self-catheterisation. He developed bladder stones and electrohydraulic lithotripsy (EHL) was performed in May 2002. All stone fragments were removed. Recurrence of vesical calculi was noted in October 2002. These stones were fragmented by lithoclast lithotripsy in two sessions, in December 2002 and February 2003; all stone fragments were removed at the end of the second session. This patient reverted to indwelling catheter drainage when vesical calculi recurred. In September 2003, X-ray of the abdomen showed recurrence of vesical calculi. By February 2004, the stones had increased in size and number. EHL of vesical calculi was again performed in April 2004. Complete clearance was achieved. RESULTS: A 24-h urinalysis detected hypercalciuria--18.7 mmol/day (reference range: 2.5-7.5). Biochemical analysis of vesical calculus revealed calcium phosphate (85%) and magnesium ammonium phosphate (15%). Plasma C-terminal telopeptide (CTX) was increased - 1.06 ng/ml (reference range: 0.1-0.5 ng/ml). Free deoxypyridinoline/creatinine ratio (fDPD/Cr) in urine was also increased - 20.2 (reference range: 2.3-5.4). In April 2004, this patient was prescribed disodium etidronate 400 mg day. Nearly 3 months after commencing therapy with etidronate, plasma CTX decreased to 0.87 ng/ml. fDPD/Cr in urine also decreased to 12.4. After 4 months of etidronate therapy, 24-h urinary calcium excretion had decreased to 6.1 mmol/day. CONCLUSION: Etidronate (400 mg daily) is a very effective inhibitor of calcium phosphate crystallisation. Etidronate decreased urinary excretion of calcium, an important factor in prevention of calcium phosphate bladder stones. Etidronate therapy is not a substitute for other well-established methods for prevention of vesical calculi in spinal cord injury patients, for example, large fluid intake, avoiding long-term catheter drainage. Intermittent therapy with etidronate may be considered in selected patients, in whom hypercalciuria persists after instituting nonpharmacological therapy for an adequate period, for example, early mobilisation, weight-bearing exercises, and functional electrical stimulation. However, possible side effects of etidronate, and the fact that etidronate is not licensed in United Kingdom for prevention of urolithiasis, should be borne in mind.

Adult↗

PubMed2005

Epidemiology of the optic nerve grey crescent in the Reykjavik Eye Study.

AIM: To establish the epidemiology of the grey crescent in a white population within the age range most susceptible to glaucoma. METHODS: Bruce Shields was first to use this term to describe a localised, physiological pigmentation of the optic nerve neuroretinal rim tissue that is distinct from peripapillary pigmentation. An experienced glaucomatologist (KFD) evaluated stereofundus photographs of the participants of the Reykjavik Eye Study (RES)-a random sample from the national population census including people 50 years and older. 1012 right eyes could be evaluated for grey crescent. RESULTS: The prevalence of grey crescent in the right eyes was 22.0% (95% CI 10 to 25). It was more commonly found in women (27.0%: 95% CI 23 to 30) than in men (17.0%: 95% CI 14 to 21), and was most often located temporally (36.9%), 360 degrees (15.9%), or nasally (15.4%). The spherical equivalent was +1.30 dioptres (D) for those with and +0.80 D for those without grey crescent (p = 0.002), respectively. Vertical optic disc diameters were 0.203 v 0.195 units (p<0.001). There was no difference in the prevalence of grey crescent in glaucomatous or non-glaucomatous eyes (OR = 1.05, 95% CI 0.49 to 2.26). The prevalence of a grey crescent was inversely related to the prevalence of peripapillary atrophy (p = 0.001). CONCLUSIONS: The grey crescent needs to be recognised as a physiological variant in order to avoid falsely labelling eyes as having glaucomatous optic nerve damage.

Aged↗

PubMed2002

In vitro determination of active bile acid absorption in small biopsy specimens obtained endoscopically or surgically from the human intestine.

BACKGROUND: In the construction of a Kock reservoir for continent urinary diversion, 70 cm of the distal ileum are used. Impaired absorption of bile acids in these patients might cause diarrhoea. Data on the absorption of bile acids in different parts of the human intestine are limited. METHODS: Biopsies were taken during endoscopy from the duodenum, the terminal ileum or the right colon, and during surgery 10, 50, 100 and 150 cm proximally to the ileo-caecal valve using standard endoscopy biopsy forceps. The biopsy specimens were incubated in vitro with radio-labelled taurocholic acid at 37 degrees C for 22 or 45 min The radioactivity was determined using the liquid scintillation technique. RESULTS: A linear increase in the uptake was observed, with increased concentrations of taurocholic acid between 100 and 500 microm in all specimens tested, that represented passive uptake or unspecific binding. The active uptake could be calculated from the intercept of the line representing passive uptake with the ordinate. The active uptake in the terminal ileum was 3-4 times greater than 100 cm proximal to the valve. CONCLUSIONS: The active absorption of bile acids in humans can be determined in small biopsy specimens taken using standard biopsy forceps during endoscopy or surgery. This method is suitable for clinical studies of bile acid absorption. Active uptake of bile acids not only takes place in the very distal part of the ileum but also to a considerable degree 100 cm proximally to the ileo-colonic valve. This should be taken into account when selecting the ileal segment for continent urinary diversion.

Adult↗

PubMed2001

Hydrophilic versus non-coated catheters for intermittent catheterization.

Since Lapides reintroduced clean intermittent catheterization (CIC) in 1972, this procedure has been used routinely in individualized programmes for bladder evacuation in various bladder disorders. It has been suggested that in clinical practice hydrophilic catheters are preferable to non-coated catheters. In reviewing the literature on CIC, many of the reports were found to rely on data from non-randomized retrospective studies. In some recent prospective studies, involving a limited number of patients, hydrophilic and non-coated catheters have been evaluated and compared, especially with regard to bacteriuria and urethral irritation. The available data indicate that using hydrophilic catheters for CIC may induce lower rates of bacteriuria and long-term urethral complications such as urethral strictures. However, to reach a reliable conclusion about the supposed advantage of the hydrophilic catheters, there is a need for a prospective, randomized long-term multicentre study. It is important in such a study to define patient characteristics including age, gender, diagnosis of bladder dysfunction, reason for CIC, physical and mental handicap, manual dexterity and previous treatments. Effect parameters should include number of catheterizations, urinary tract infection, early and long-term urethral complications, patient satisfaction, preferences and dropout rates. It is obligatory to include factors such as cost-benefit and cost-effectiveness.

Adolescent↗

PubMed2001

Reconstructive urology in the nordic countries--a hospital questionnaire survey.

A hospital survey of adult reconstructive urologic surgery in the Nordic countries is presented. The response rate was 80% and included most general hospitals and university clinics. Despite similarities between the healthcare systems of the various countries several differences were found. Cystectomy was performed in a large number of institutions in all countries except Denmark. The annual number of orthotopic bladder substitutions per institution was calculated as three to four (range of medians for each country) and the number of continent cutaneous diversions as two to seven. Open urethral procedures were performed more frequently in Sweden than in the other countries. Surgery for penile curvature and implantation of three-component prostheses for erectile dysfunction was more commonly performed in Denmark and Iceland compared to Sweden.

Denmark↗

PubMed2001

Vitamin B12 metabolism after urinary diversion with a Kock ileal reservoir.

OBJECTIVE: To elucidate the influence of construction of a Kock reservoir for urinary diversion using 70 cm of the distal ileum on vitamin B12 metabolism. MATERIAL AND METHODS: Blood samples for determination of cobalamin concentrations were drawn up to 18 years after construction of a Kock reservoir in 97 patients. Preoperative values were obtained in 20 of these patients. Pre- and postoperative Schilling tests and analyses of methylmalonic acid and homocysteine concentrations were performed in subgroups. RESULTS: The operation did not induce a significant decrease in cobalamin uptake as reflected in the pre- and postoperatively performed Schilling tests. No significant decline in cobalamin concentration postoperatively was noted. The value of analysis of methylmalonic acid and homocysteine concentrations in finding patients with cobalamin deficiency is limited by the fact that kidney function influences the results. Ten per cent of the patients did develop true cobalamin deficiency. A postoperative vitamin B12 value below 200 pmol/l indicates a 50% risk of later cobalamin deficiency. CONCLUSIONS: The construction of a Kock reservoir does not per se cause cobalamin deficiency. Substitution should be instituted at a postoperative concentration below 200 pmol/l.

Adult↗

PubMed2001

Production of free radicals measured by spin trapping during operations for stenosis of the carotid artery.

OBJECTIVES: To analyse production of free radicals during operations for stenosis of the internal carotid artery. SETTING: University hospital, Sweden. SUBJECTS: 10 patients operated on for carotid artery stenosis. INTERVENTIONS: Blood samples were repeatedly drawn from the sigmoid sinus through a catheter in the internal jugular vein on the same side, before, during, and after clamping of the internal carotid artery. OXANOH was added to the blood samples in vitro and the radical production calculated from the amount oxidised to OXANO as electron spin resonance. MAIN OUTCOME MEASURES: The relation between radical production and certain clinical variables investigated by partial least squares regression analysis. RESULTS: There were several significant relations. High systolic blood pressure and advanced age were associated with low, and severe degree of stenosis with increased, free radical production. Certain anaesthetic drugs as well as blood variables also influenced the production of radicals. CONCLUSIONS: The technique used seems to offer the possibility to find and study methods to reduce free radical production during this kind of operation.

Age Factors↗

PubMed2001

Long-time experience with the Kock ileal reservoir for continent urinary diversion.

OBJECTIVES: N.G. Kock performed the first continent cutaneous ileal reservoir for urinary diversion in 1975 at the Sahlgrenska University Hospital, Göteborg, Sweden. We have investigated the fate of the patients operated during the following 25 years at this hospital and analyzed their health-related quality of life (SF-36) as well as their psychological adjustment to a life with a continent urinary reservoir (OAS). MATERIAL AND METHODS: Between 1975 and 1999, 176 patients underwent continent urinary diversion using a Kock reservoir. At the end of 1999, 126 patients were known to be alive. Their reservoir function was estimated from their journals as well as from a questionnaire answered by the patients. RESULTS: Almost 90% of the survivors had a well-functioning reservoir at the time of follow-up. The need for reoperation has been high, mainly due to nipple problems. Kidney function is not influenced by the continent diversion per se. The health status of the patients is more influenced by the underlying disease than by their reservoirs. Patients with benign functional or inflammatory diseases experience comparatively more problems with their reservoirs. CONCLUSIONS: The functional end results as well as patient acceptance of continent urinary diversion with a Kock reservoir are excellent.

Adult↗

PubMed1999

Increase in doxorubicin cytotoxicity by carvedilol inhibition of P-glycoprotein activity.

Acquired resistance to chemotherapy is a major problem during cancer treatment. One mechanism for drug resistance is overexpression of the MDR1 (multidrug resistance) gene encoding for the transmembrane efflux pump, P-glycoprotein (P-gp). The calcium channel blocker verapamil has been shown to reverse cellular drug resistance by inhibiting P-gp drug efflux. This study evaluated whether the new antihypertensive drug carvedilol influenced doxorubicin (Dox) cytotoxicity and P-gp activity in a P-gp-expressing cell line compared to a non-expressing subline. Verapamil (10 micromol/L), and even more markedly, carvedilol (10 micromol/L) increased cellular uptake of P-gp-transported calcein of a P-gp-expressing breast cancer cell line (Hs578T-Dox). In the subline (Hs578T) not expressing P-gp, no effects of carvedilol or verapamil on calcein uptake were seen. Carvedilol and verapamil (10 micromol/L) reduced the LD50 (dose which results in the death of half the number of cells) of the Hs578T-Dox subline from 200 mg/L to approx. 10 mg/L Dox, whereas the LD50 of the Hs578T subline was only marginally affected. Carvedilol (10 micromol/L) reduced P-gp activity approximately twice as effectively as verapamil at an equimolar concentration. Carvedilol did not affect pyrogallol cytotoxicity and pyrogallol was without effect on calcein accumulation of the Hs578T-Dox cell line, indicating the lack of antioxidative properties affecting P-gp activity and associated toxicity of the drug. The results suggest that carvedilol has the clinical potential to reverse tumour MDR involving the efflux protein P-gp.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1999

Determinants of bone loss in patients with Kock ileal urinary reservoir.

The purpose of the present study was to determine the change in bone mineral density (BMD) measured with dual energy X-ray absorptiometry (DXA) in patients with Kock reservoirs for urinary diversion who were examined with the same technique 3 years earlier, and relate the changes to kidney function and variables reflecting bone metabolism. A total of 28 patients with Kock ileal reservoirs to the skin (23) or urethra (5) were reinvestigated 3 years after the first measurement. BMD was measured in the lumbar spine, femur and whole body with DXA. Bone specific alkaline phosphatase, osteocalcin, parathyroid hormone (PTH), calcitonin and chloride were also determined in serum. GFR was determined from the plasma clearance of 51Cr-EDTA. The mean values for BMD expressed in percentage of corresponding mean values for age-matched controls (BMD%) were almost identical after 3 years. Only osteocalcin levels correlated with the BMD% values. However, significant positive correlations were found between GFR and the observed individual changes in BMD% over the 3 years in spite of the fact that most GFR values were fairly normal. Enhanced bone loss was associated with high concentrations of osteocalcin and bone specific alkaline phosphatase. Comparisons with blood gas analyses and determination of 1,25 dihydroxyvitamin D performed in the previous study indicate to us that the relation between reduced GFR and low mineral content might, in part, be related to a low-grade metabolic acidosis and reduced availability of the biologically active vitamin D hormone. The conclusion to be drawn is that urinary diversion with a Kock reservoir does not regularly cause bone demineralization. However, patients with even moderately reduced GFR appear to be at risk for developing osteoporosis in the long-time run.

Adult↗

PubMed1998

Bile acid malabsorption after continent urinary diversion with an ileal reservoir.

PURPOSE: We determine the effect of urinary diversion with a Kock ileal reservoir on bile acid absorption and bowel habits. MATERIALS AND METHODS: We asked 96 patients with a Kock ileal urinary reservoir to record bowel habits and abdominal symptoms for 1 week. Data on 75 patients were further analyzed. Bile acid absorption was determined in 29 healthy control subjects, in 17 before and 6 months after continent urinary diversion, and in 21, 2 to 14 years postoperatively. Bile acid absorption was considered pathological when retention of less than 10% of an oral capsule containing selenium-75 labeled tauroselcholic acid (SeHCAT) was noted after 1 week. RESULTS: Mean number of defecations plus or minus standard deviation was 9.4 +/- 6.1 (75 cases). Of the patients 13% had 15 or more stools per week and 15% complained of always having loose stools. Mean value for the SeHCAT test was 32 +/- 19% preoperatively and 17 +/- 16% 6 months postoperatively (p = 0.0023). The corresponding value for healthy controls was 39 +/- 18%. Significant relationships were found between the results of the SeHCAT test postoperatively, and the number of stools per week and consistency of the feces. All patients with more than 10 defecations per week had a pathological SeHCAT test. CONCLUSIONS: Most patients with an ileal urinary reservoir have fairly normal bowel habits. Bile acid absorption is significantly reduced postoperatively and approximately a third of the patients have a pathological SeHCAT test. Preoperative investigation of bowel habits is recommended and a SeHCAT test should be performed in patients with frequent, loose defecations. Other types of diversion should be offered when preoperative retention is below 10 to 20% especially in patients with impaired anal control.

Absorption↗

PubMed1998

In vivo 31P NMR OSIRIS of bioenergetic changes in rabbit kidneys during and after ischaemia: effect of pretreatment with an indeno-indole compound.

Changes in energy phosphates of rabbit kidneys subjected to ischaemia-reperfusion have been measured in vivo with volume selective 31P NMR spectroscopy. The effects of pretreatment with a new lipid peroxidation inhibitor (indeno-indol derivate--code name H290/51) on the bioenergetic changes were analysed. The left kidney was moved to a subcutaneous pocket to facilitate exact positioning over the surface coil. A 1H NMR image was acquired and a 3.5-mL cube selected for 31P NMR spectra. 31P NMR spectra were recorded before occlusion of the left renal artery, during 1 h of ischaemia and 2 hours of reperfusion. Ischaemia induced drastic changes in the levels of inorganic phosphates and ATP as well as intracellular acidosis. A normalization was observed during reperfusion. Two hours after reperfusion significantly higher values for beta-ATP/Pi and intracellular pH were recorded in the animals pretreated with H290/51. The present technique allows quantitative analyses of changes in kidney bioenergetics in vivo during different experimental conditions. The importance of ischaemia-reperfusion induced lipid peroxidation for mitochondrial function is emphasized.

Adenosine Triphosphate↗

PubMed1998

Relationship between salt and blood pressure in hypertensive patients on chronic ACE-inhibition.

We investigated the effect of a 4-day oral salt load (150 mmol NaCl extra per day) on blood pressure, erythrocyte sodium transport and the activity in the renin-angiotensin system in six males with primary hypertension, who had attained normotension on chronic enalapril treatment for 4 years. The design was a placebo-controlled, randomized, two-way cross over, double-blind study, i.e. each patient served as his own control. Intracellular erythrocyte sodium and potassium content were measured by flame photomometry. The increase in the intracellular sodium concentration during 1 h in 37 degrees C incubation of whole-blood with ouabain (compared with no-ouabain) was measured to determine the rate of active sodium efflux. 24-h blood pressure registration was performed with Space-lab equipment (SL 90202) before and at the end of the salt load. Left ventricular morphology was evaluated with echocardiography and the minimal vascular resistance of the hand vascular bed with water plethysmography at baseline and after 4 years on enalapril. Four years' enalapril treatment caused a significant decrease in blood pressure, left ventricular mass and minimal vascular resistance. During the 4-day salt load average 24-h blood pressure was significantly elevated, 129+/-3/85+/-2 mmHg as compared to 124+/-2/82+/-2 mmHg during placebo treatment (p=0.025). The change (delta) in MAP during high salt intake showed a negative relationship to delta-sodium efflux rate constant (r=-0.65, p=0.047). No significant relationship was found between the blood pressure response to the salt load and structural cardiovascular changes. In conclusion, a short-term oral salt load in hypertensive patients on chronic enalapril treatment caused a blood pressure rise, which was related to cellular sodium transport but not to structural cardiovascular changes.

Administration, Oral↗

PubMed1997

Computerized detection of morphological changes to glioma cells during estramustine and ion-channel blocker perifusion.

A perifusion technique for microscopy with computerized detection of early changes in cell morphology during continuous perifusion was used to show that the geometry of cultured glioma cells (MG-251) changes rapidly when they are exposed to estramustine phosphate (EMP). When the cells were exposed to 20 or 40 mg l(-1) EMP, cell volume projected cell area (PCA) rapidly increased. When the Na+,K+-ATPase blocker ouabain (100 micromol l(-1)) was added to the EMP (40 mg l(-1)) perifusion, the acute EMP response was eradicated. When the PCA curve for ouabain alone was subtracted from the curve of combined ouabain and EMP perifusion, the resulting curve showed that ouabain completely blocked the EMP-induced increase in PCA. When the Na+, K+, Cl- co-transport inhibitors bumetanide (10 micromol l(-1)), or furosemide (100 micromol l(-1)), were added to EMP (40 mg l(-1)), the acute increase in PCA seen for EMP alone was also completely blocked. This study shows that inhibitors of ion transmembrane transport can modify EMP-induced cell volume increases. This may be of particular importance since the blockers have been found to interfere also with the cytotoxic function of EMP during cell culture. Thus, it is possible that cell volume changes could serve as a rapid technique for predicting the cytotoxic activity of antineoplastic drugs.

Bumetanide↗

PubMed1997

Effects of pretreatment with an indeno-indole compound on lipid peroxidation in the cortex and medulla of rabbit kidneys after ischaemia-reperfusion.

The effects of 60 min of ischaemia with or without reoxygenation in vivo or in vitro on lipid peroxidation in cortical and medullary tissue from rabbit kidneys were measured as production of thiobarbituric acid-reactive substances (TBARS). Lipid peroxidation was more pronounced in medullary tissue compared with cortical tissue. The highest TBARS production was found in medullary slices subjected to reoxygenation in vitro immediately after 1 h of ischaemia. Reperfusion in vivo before reoxygenation in vitro attenuated the TBARS formation during subsequent in vitro incubation. Pretreatment of the rabbits with an indeno-indole compound (code name H 290/51) reduced the TBARS formation after 60 min of ischaemia and reoxygenation in vitro towards control values.

Animals↗

PubMed1997

Method for long-term intestinal access in the dog.

A variety of devices have been used to establish long-term intestinal access in laboratory animals. Their use is complicated by infection, tissue reaction, and a frequent need for single housing to prevent implant damage. Intussuscepted nipple valves have long been used in the human field of surgery for various applications where there is a need to create a reservoir without leakage. With the use of the nipple valve it was possible to establish long-term intestinal access in dogs with minimal post-operative complications, no leakage and, because no foreign material was used, no complications due to tissue rejection. The advantages of a nipple valve over the similar technique of a straight stoma is less postoperative complications in the form of leakage as well as enhanced access due to the design of the nipple valve. Encouraging results prompted us to widen the use of nipple valves to 14 dogs in which it has been possible to establish long-term colonic or duodenal/ileal access at one or two sites. Nine of the dogs are still in use with duration of instrumentation for some animals exceeding 60 weeks. This method requires minimal maintenance, does not prevent group housing of instrumented dogs or outdoor activities nor does it compromise the quality of life for the animals.

Anesthesia↗

PubMed1997

Perforation of continent urinary reservoirs. Scandinavian experience.

In a questionnaire survey of urological departments in Sweden, Denmark, Finland and Norway, 20 episodes of perforation of continent urinary pouches were found to have occurred in 18 patients, representing an incidence of 1.5%. This complication occurred with ileal as well as colonic segments, without predilection. In one case there was perforation of an appendiceal outlet. Noticeable findings were (a) a long delay (median 10h) to treatment and (b) that investigational procedures such as enterocystography and enterocystoscopy were not commonly employed. Treatment of this potentially lethal complication was by oversewing the perforation, and there were no subsequent major complications. This complication should be strongly suspected if a patient with continent urinary reconstruction presents with acute abdominal pain.

Abdominal Pain↗