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J K Kristensen

Publications and source records attributed to J K Kristensen.

At least 19 recordsLinked to original sources
PubMed2005

The effect of penile vibratory stimulation on male fertility potential, spasticity and neurogenic detrusor overactivity in spinal cord lesioned individuals.

PURPOSE: Present the possibility for treatment of male infertility, spasticity, and neurogenic detrusor overactivity in spinal cord lesioned (SCL) individuals with penile vibratory stimulation (PVS). METHOD: Obtaining reflex-ejaculation by PVS, by using a vibrator developed for this purpose. The stimulation was performed with a vibrating disc of hard plastic placed against the frenulum of the penis (amplitude > or = 2.5 mm). The vibration continued until antegrade ejaculation or for a maximum of 3 minutes followed by a pause of 1 minute before the cycle was repeated, maximally 4 times. RESULTS: >80% SCL men are able to obtain ejaculation with PVS. Pregnancy rates obtained with home PVS and intra-vaginal insemination was 22-62% (4 studies), and with PVS or electroejaculation and intrauterine insemination/in-vitro fertilization/intracytoplasmatic sperm injection 39-64% (9 studies). PVS was demonstrated to decrease spasticity significantly when measured by the modified Ashworth scale. In addition, a decrease of the number of spontaneous EMG events which probably indicate spasms was observed. Increase in bladder capacity at leakpoint following 4 weeks of frequent ejaculation with PVS treatment was likewise demonstrated. CONCLUSION: PVS has proved its importance for SCL male fertility, in the years to come its place in treatment of spasticity and neurogenic detrusor overactivity has to be established.

Humans↗
PubMed2004

Bladder emptying over a period of 10-45 years after a traumatic spinal cord injury.

STUDY DESIGN: Epidemiological follow-up study. OBJECTIVE: To examine the bladder-emptying methods at least 10 years after a traumatic spinal cord injury (SCI). SETTING: Clinic for Para- and Tetraplegia and Department of Urology, Rigshospitalet, Copenhagen University Hospital, Denmark. METHODS: Retrospective data collection from patient records and data collected with a follow-up questionnaire. The response rate was 84.6% corresponding to 236 SCI individuals, injured in 1956-1990. There were 82/18% male/female patients and 47/53% tetraplegic/paraplegic. Age at the time of follow-up was 50.5 years in mean (range 28-84). Years from time of injury were 24.1 years in mean (range 10-45). RESULTS: The use of clean intermittent catheterisation (CIC) rose from 11% at the initial discharge to 36% at the time of follow-up. The use of suprapubic tapping fell from 57 to 31% in the same period, while the use of Crede manoeuvre rose from 5 to 19%. During follow-up, 46% changed bladder-emptying method. The results showed the following trends in change of method: a high proportion of discontinuation in normal bladder emptying, suprapubic tapping and abdominal pressure and a high proportion of continuation when using CIC. 28% found their bladder-emptying method to be a problem; of these 58% were tetraplegic. Of the participants using CIC, 92% reported using hydrophilic-coated catheters. CONCLUSIONS: Changing of bladder-emptying method among SCI individuals over time is common. CIC alone or in combination with another bladder-emptying method is the most frequently used method of bladder emptying. SPONSORSHIP: The study was carried out as part of the primary author's PhD-study, which was financed by Medicon Valley Academy and Coloplast A/S.

Adult↗
PubMed2004

Quantitative analysis of retinopathy in type 2 diabetes: identification of prognostic parameters for developing visual loss secondary to diabetic maculopathy.

PURPOSE: To describe whether quantitative assessment of early changes in the morphology of retinopathy lesions can predict development of vision-threatening diabetic maculopathy. METHODS: We used a nested case-control study, and we studied 11 type 2 diabetes patients who had developed visual loss secondary to diabetic maculopathy. For each diabetes patient, we also studied three matched control patients who had been followed for a comparable period of time without developing visual loss. Fundus photographs describing the early development of retinopathy were digitized and subjected to a full manual quantitative grading on a computer monitor. Differences in the early development of retinal morphology were compared between the two groups. The outcome parameters were changes in the number and area of haemorrhages and exudates in different regions of the fundus, and the weighted distance of these lesions from the fovea and the optic disc. RESULTS: In patients who developed visual loss secondary to diabetic maculopathy there was significant early progression in the total area and number of haemorrhages and exudates. The haemorrhages had progressed in all retinal areas except the area around the optic disc and the temporal vascular arcades. The exudates had progressed temporally from the fovea and in the retinal periphery. CONCLUSIONS: The results suggest that a quantitative description of the regional development of early diabetic retinopathy may help in identifying patients who will later develop vision-threatening maculopathy.

Adult↗
PubMed2002

Elevated plasma levels of vascular endothelial growth factor and plasminogen activator inhibitor-1 decrease during improvement of psoriasis.

OBJECTIVE AND DESIGN: An evaluation of angiogenesis related molecules during open treatment of psoriasis. MATERIALS AND SUBJECTS: Plasma samples and skin biopsies from 16 patients with psoriasis and plasma samples from 13 healthy controls. TREATMENT: Ranitidine 300 mg orally twice daily for 6 months. METHODS: Vascular endothelial growth factor (VEGF) and plasminogen activator inhibitor-1 (PAI-1) were determined by ELISA methods in plasma collected from the patients before treatment and after 1, 3 and 6 months. Vessel counts were performed in biopsies from affected skin areas taken before treatment and after 3 and 6 months. The results were compared to simultaneous PASI scores. RESULTS: Pre-treatment plasma levels of VEGF and PAI-1 were significantly elevated in patients compared with levels in healthy persons (p = 0.02 and p = 0.04, respectively). The plasma levels decreased significantly during treatment (p = 0.03 and p = 0.01, respectively), and the decrease in combined levels correlated with the decrease in PASI score. However, the vessel density in affected skin did not change during treatment. CONCLUSIONS: Increased pre-treatment levels of VEGF and PAI-1 and decrease during improvement of the disease suggest that the two molecules may play a role in pathogenesis of psoriasis.

Adult↗
PubMed2001

HbAlc in an unselected population of 4438 people with type 2 diabetes in a Danish county.

OBJECTIVE: To describe the use and level of HbA1c in a large unselected Type 2 diabetic population in Denmark. In addition, to describe the characteristics of the patients and the general practitioners in relation to the monitoring of HbA1c. DESIGN: Data were collected from public data files for the period January 1993 to December 1997. SETTING: The County of Vejle with a background population of 342,597 citizens, 303,250 of whom were listed with participating general practitioners. PATIENTS: The Type 2 diabetic population alive and resident in the county on 1 January 1997. RESULTS: In a population of 4438 Type 2 diabetics, 73% had a minimum of one annual HbA1c measurement in 1997. No HbA1c measurement was associated with a long history of diabetes, diet treatment or old age. Poor glycaemic regulation was found in 65% of the Type 2 diabetics in 1997. Poor glycaemic regulation was associated with tablet or insulin treatment, age under 70 years and long history of diabetes. The interpractice variation was huge. CONCLUSION: The quality of HbA1c monitoring of Type 2 diabetics needs to be improved. Possibilities for improvement seem to be present.

Aged↗
PubMed2001

Use and validation of public data files for identification of the diabetic population in a Danish county.

INTRODUCTION: This study aims to describe the process of identifying people known to have diabetes through public data files, to validate this method, and to describe models for optimization of such identification processes. PATIENTS AND METHODS: In a study population of 303,250 citizens, the diabetics were identified by combining information from public data files with information from general practitioners. Data validity was checked by comparing the results of data searches in public data files against information from general practitioners and a random sample of diabetics. Two models were defined to optimize the use of public data files for identification of diabetics. In model A the minimum number of parameters needed to obtain a sensitivity as high as possible was identified. In model B the optimal combination of parameters needed to obtain a high positive predictive value combined with a high sensitivity was identified. RESULTS: A total of 5449 diabetics were identified. Of those 4438 (81%) were classified as Type 2 diabetics and 1011 (19%) were classified as Type 1 diabetics. The data validation revealed that one person was misclassified as a diabetic and 93 persons were misclassified as non-diabetics. In model A the identification parameters included: "prescription", "HbA1c", "chiropodist service" and "glucose service". In model B the optimal combination of parameters was identified as: minimum two HbA1c measurements, minimum one visit to a chiropodist, minimum one prescription or minimum one abnormal HbA1c during one year. CONCLUSION: Public data files are suitable for identification of both Type 1 and Type 2 diabetics. Models have been developed to identify diabetics and to promote the possibilities of long-term follow-up and quality assessment in an unselected diabetic population in a region.

Adult↗
PubMed2000

Cerebral activation during micturition in normal men.

Specific cerebral lesions have shown the crucial role of the brain in the control of micturition. The precise identification of the anatomical cerebral structures involved in micturition can contribute to a better understanding of the control of micturition and the development of therapeutic models. Various neuropathological and animal studies have referred to the medulla oblongata, pons, limbic system, superior frontal lobe and premotor cortical regions as areas implicated in micturition control. The aim of this study was to investigate whether the activity of these areas during micturition can be confirmed by PET in normal men. The distribution of the regional cerebral blood flow after bolus injection of (15)O water was used as an indirect measure of cerebral activation. PET scans were performed during the following three conditions: (i) at rest with the bladder empty; (ii) during simulated micturition after instillation of isotonic saline into the urinary bladder; and (iii) the withholding of urine (saline). Normal micturition using this model was achieved in eight out of 12 right-handed normal subjects. The changes in bladder contraction, bladder pressure and intra-abdominal pressure were monitored on-line during the whole scanning session by a cystometry device. The images were analysed using statistical parametric mapping at a significance threshold of P < 0.05 with correction for multiple independent comparisons. Micturition versus rest was associated with bilateral activation of areas close to the postcentral gyrus, inferior frontal gyrus, globus pallidus, cortex cerebelli, vermis and midbrain. On the left side, activation of the middle frontal gyrus, superior frontal gyrus, superior precentral gyrus, thalamus and the caudal part of the anterior cingulate gyrus was seen, while on the right side we found activation in the supramarginal gyrus, mesencephalon and insula. When the threshold value was lowered to P < 0.001 (Z > 3.09) without correction for multiple comparisons, we found additional activation in the medial pontine tegmentum, mesencephalon, right thalamus, right middle frontal gyrus and left insula. When urine- withholding was compared with rest, the left insula showed a tendency to activate. We conclude from this study, in which urinary bladder contraction was verified cystometrically, that the onset and maintenance of micturition in normal men is associated with a vast network of cortical and subcortical regions, confirming observations from clinical and animal studies.

Adult↗
PubMed1999

[Quality assessment of diabetes care in a large general practice. Identification and biomedical status].

The aims of this study were to describe the diabetic population and to evaluate the routine diabetic care in one general practice. All patients with recognized diabetes were included. Information was collected from each patient's record and from patients' and doctors' questionnaire. One hundred an fourty (1.8%) of the patients had recognized diabetes and 81% of these diabetes had non-insulin-dependent diabetes (NIDDM). According to the records, HbA1c had been monitored in 85% of the NIDDM patients in the preceding year and in 76% of the IDDM patients. The corresponding figures for albuminuria were 84% vs. 76%, for S-creatinine 74% vs. 81%, for S-cholesterol 37% vs. 24%, for weight 47% vs. 43%, for blood pressure 60% vs. 48%, for foot care 67% vs. 62% and for eye examination 76% vs. 75%. International targets for good control were obtained for HbA1c in 42% of cases, for weight in 23%, for blood pressure in 30% and for S-cholesterol in 40% at the last control. The results of the study indicate that there is a continuous demand for quality monitoring and improvement of diabetic care in general practice.

Adolescent↗
PubMed1999

Effect of repeated ejaculation on semen quality in spinal cord injured men.

PURPOSE: We evaluate the effect of repeated ejaculations on semen quality in spinal cord injured men. MATERIALS AND METHODS: The study included 19 spinal cord injured men with anejaculation. Semen was obtained by penile vibratory stimulation in the clinic and patients were instructed in the technique. Optimized vibration parameters were used (2.5 mm. amplitude at 100 Hz.). Penile vibratory stimulation was performed at least once a week for 12 months. Semen quality was examined at baseline and every 3 months during the 1-year study period. Hormonal assays were also performed at each visit. In 9 patients unilateral testicular biopsy was done at baseline and at the end of the 12 months. RESULTS: Normal sperm counts and low motility were seen at baseline. No semen parameter significantly changed during the 12 months of repeated ejaculation. All hormonal assays during the entire study were within normal range and no significant change was observed. Of the 9 biopsies 6 (67%) showed normal spermatogenesis at baseline and no convincing qualitative changes in testicular histology were seen after repeated ejaculation. CONCLUSIONS: Repeated ejaculation in spinal cord injured men does not change the typically poor semen quality. Therefore, stagnation in the seminal ducts due to infrequent ejaculation is not the etiology of the poor semen quality in these patients.

Adult↗
PubMed1999

False iliac artery aneurysm following renal transplantation.

We report a very rare case of a false iliac artery aneurysm following renal transplantation. The patient was a 51-year-old women who presented with a painful 10 x 10 cm pulsating mass in her left iliac fossa. The patient had received a second cadaveric renal transplantation 5 years previously. The graft never functioned and transplant nephrectomy was performed 2 weeks later. A CT-scanning showed a 10 x 10 cm large aneurysm arising from the left external iliac artery. At operation a large false aneurysm was identified arising from the original transplant anastomotic site. Due to the extent of the aneurysms, a Gortex graft was inserted between the external iliac artery and the common femoral artery. The patient made an uneventful post-operative recovery.

Aneurysm, False↗
PubMed1998

Seminal plasma PSA in spinal cord injured men: a preliminary report.

OBJECTIVE: The aim of the study was to evaluate the impact of spinal cord injury on seminal plasma PSA concentration. MATERIAL: Semen obtained from normal controls (n = 20) and patients (n = 16) with spinal cord injury. RESULTS: The concentration of prostate specific antigen in seminal plasma depended on the level of spinal cord injury, with significantly lower concentrations in patients with spinal cord lesions below T7 compared to both normal age-matched controls (P = 0.007) and patients with spinal cord injuries at or above T7 (P = 0.017). CONCLUSIONS: The results add to the previously reported observations of the possible impact of neurogenic stimulation on prostate activity. More studies of neurogenic stimulation in prostate growth and development are warranted to further elucidate the possible impact of neurogenic factors in the development of prostatic diseases.

Adult↗
PubMed1998

Studies on mast cells and histamine release in psoriasis: the effect of ranitidine.

The purpose of this study was to investigate histamine and skin mast cells in psoriasis before and during 6 months of treatment with high-dose ranitidine. Sixteen psoriasis patients, presenting a mean PASI score of 15.4, were compared with 13 age- and sex-matched healthy controls. Resting extracellular skin levels of histamine and histamine release to mast cell secretagogues, as measured by the microdialysis technique, were increased in involved psoriasis skin compared to normal skin in the controls. Plasma histamine, but not basophil histamine release, was significantly increased in the patients. Mast cells and lymphocytes were significantly increased in numbers in involved versus non-involved skin in the patients, the lymphocytes being predominantly T-lymphocytes expressing HLA-DR activation. During 6 months of ranitidine treatment, mean PASI score of 15.4 decreased to 5.8. The lymphocyte infiltration, but not mast cell numbers, was significantly reduced during treatment, and histamine release to mast cell secretagogues was normalized. These observations suggest that skin mast cells in active psoriasis are functionally hyperreactive. The biochemical findings together with the clinical effect of ranitidine indicate that histamine may be involved in the pathophysiology of psoriasis.

CD4-CD8 Ratio↗
PubMed1997

[Clinical effect of ranitidine in psoriasis. An open prospective study].

We report the results of an open, prospective study of 20 patients with moderate to severe psoriasis (median PASI score: 15.7) treated with oral ranitidine 300 mg twice daily for six months. No other medication was allowed during the study period. The median PASI score was reduced to 14.5, 9.1 and 5.7 after one, three and six months of treatment, respectively (p < 0.00001). A mild to moderate worsening was observed in 15 patients within the first month of treatment, but this was not followed by exclusion from the study, and long-term treatment improved disease status in most patients. Eight patients continued therapy with ranitidine 300 mg twice daily after the study was completed. None of these patients relapsed during a follow-up period of 12-18 months. The results of the present study suggest that ranitidine may be beneficial in the treatment of some patients with psoriasis.

Adult↗
PubMed1997

Pregnancy after assisted ejaculation procedures in men with spinal cord injury.

OBJECTIVE: To present the results of fertility treatment in 28 men with spinal cord injury (SCI) and their partners. DESIGN: Retrospective analysis. SETTING: University hospital outpatient clinic and home. PATIENTS: Twenty-eight anejaculatory men with SCI and their partners seeking treatment for infertility. INTERVENTION: Penile vibratory stimulation and electroejaculation as semen retrieval methods. Assisted reproductive techniques used: vaginal self-insemination at home, intrauterine insemination, in vitro fertilization with or without intracytoplasmic sperm injection. MAIN OUTCOME MEASURES: Ejaculation rate; sperm count and motility; pregnancy rates. RESULTS: All of the men were able to ejaculate either by penile vibratory stimulation (79%) or electroejaculation (21%). Median total sperm count was 65 million (range, 0.1 to 480) with a median motility of 13% (range, 1% to 60%). Overall, 9 of 28 couples (32%) achieved 10 pregnancies (4 self-insemination, 3 intrauterine insemination, 1 in vitro fertilization, and 2 intracytoplasmic sperm injection). CONCLUSIONS: An ejaculation rate of 100% was achieved using penile vibratory stimulation as a first treatment option with electroejaculation as a second option. Motivated couples with adequate semen quality may be offered penile vibratory stimulation combined with self-insemination at home. Together with intrauterine insemination or fertilization techniques used in vitro, the pregnancy rate per treatment cycle for SCI couples may approach that of natural procreation in healthy and fertile couples.

Adult↗
PubMed1996

[Evaluation and treatment of patients with kidney calculi].

Renal stone disease is a common disorder causing much discomfort and high rates of sick-leave. Surgical treatment has improved dramatically with extracorporeal shock wave lithotripsy, but the recurrence rate is high, and it would be desirable to be able to offer the patients effective steps in prevention of further stone formation. The biochemical abnormalities associated with stone formation are complex and not fully elucidated. It should, however, be possible to reduce the recurrence rate with a relatively simple programme for investigation of the patients. The pathogenesis of renal stones is, therefore, reviewed with reference to a plan for the practical approach to the prevention and management of nephrolithiasis, that has recently been recommended by The National Kidney Foundation, USA.

Humans↗
PubMed1996

Quality of semen obtained by penile vibratory stimulation in men with spinal cord injuries: observations and predictors.

OBJECTIVES: To study the semen quality and to examine prognostic factors that may affect semen quality in men with spinal cord injuries (SCI) who respond to penile vibratory stimulation (PVS). METHODS: Fifty-one PVS responders were prospectively examined. Penile vibratory stimulation was induced with optimized vibration parameters. Semen quality was characterized by semen analysis. The gel agglutination test for the presence of antisperm antibodies and serum hormone assays were performed. Characteristics of the spinal lesions, type of bladder management, and hormone assays were compared to semen quality and incidence of azoospermia or total lack of motility. RESULTS: The mean semen parameters were: volume-1.9 mL (range 0.2 to 7.0); total sperm-457 million (range 0 to 10,900); motility-12.6% (range 0% to 55%); total motile sperm-39.3 million (range 0 to 401); normal morphology-50.1% (range 0% to 90%). Better sperm motility was seen in men with cervical lesions versus those with thoracic lesions (16% versus 7%) and incomplete versus complete lesions (19% versus 10%). There was a higher incidence of azoospermic specimens in men with thoracic lesions versus cervical level (26% versus 3%) and a lower incidence of finding any motile sperm in the specimen (47% versus 81%). Men voiding without catheters had a lower incidence of azoospermia (3% versus 28%). Abnormalities of hormone and antibody tests were rare. CONCLUSIONS: Better sperm specimens from PVS of men with SCI may be expected from men with higher neurologic level, incomplete lesions, and those voiding without the use of a catheter. Hormonal abnormalities and immunologic causes do not explain the poor sperm quality seen in men with SCI.

Adult↗