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H Bülow

Publications and source records attributed to H Bülow.

At least 19 recordsLinked to original sources
PubMed2005

Cardiac magnetic resonance imaging: long term reproducibility of the late enhancement signal in patients with chronic coronary artery disease.

OBJECTIVE: To determine long term reproducibility of the late enhancement (LE) signal in contrast enhanced magnetic resonance imaging (MRI) and potential changes of the signal after revascularisation. METHODS: 33 patients (29 men, mean (SD) 61 (11) years) with coronary artery disease (CAD) and left ventricular dysfunction (ejection fraction 30 (7)%) underwent two contrast enhanced MRI procedures within 9 (3) months. Fifteen patients (group A: 14 men, 59 (12) years) had no interventions between the two studies. Eighteen patients underwent revascularisation after MRI 1 (group B: 15 men, 62 (9) years). Changes in the LE signal between the first and second MRIs were investigated in both groups as well as intraobserver and interobserver variabilities for delineation of the signal. RESULTS: The LE signal was highly reproducible in groups A and B for segmental analysis (concordance 86% v 82%, respectively; kappa = 0.70 v 0.67) and summed scores (group A: r = 0.97, p < 0.001; group B: r = 0.93, p < 0.001). The LE signal was quantified as 27 (27) cm3 in group A versus 30 (16) cm3 in group B in the first MRI and 26 (25) cm3 versus 30 (15) cm3, respectively, for the second MRI (both not significant). Moreover, low intraobserver and interobserver variabilities were observed in segmental analysis (kappa = 0.86 and 0.74, respectively, for group A, and kappa = 0.87 and 0.82, respectively, for group B). CONCLUSION: In patients with chronic CAD, the LE signal in contrast enhanced MRI is very stable over an extended time period. These results further characterise contrast enhanced MRI as a useful tool for myocardial viability assessment. Low intraobserver and interobserver variabilities promise robustness of the method for clinical application.

Aged↗
PubMed2005

Nuclear cardiology in acute coronary syndromes.

Acute coronary syndromes are a frequent manifestation of coronary artery disease, usually being associated with chest pain and presenting as a medical emergency. Since a considerable number of patients with chest pain, however, have a non cardiac etiology of their pain, properly triaging these patients represents a diagnostic challenge for physicians in the emergency department. As the available diagnostic procedures have limited accuracy, many different diagnostic strategies have been evaluated. Among these, radionuclide myocardial perfusion imaging (MPI) at rest or in combination with stress procedures has been investigated in many trials. MPI has been proven to be useful, especially in a patient population with a low to intermediate probability of an ischemic event. Perfusion scintigraphy has a high sensitivity in the detection of myocardial infarction and reveals an excellent negative predictive value, allowing a safe discharge strategy of patients with a negative scan result. Moreover, it enables risk stratification and provides incremental and independent prognostic information regarding short to long term future cardiac adverse events. Several cost effectiveness studies have shown that perfusion imaging leads to lower overall direct costs, mainly by a reduction of unnecessary hospital admissions and diagnostic angiograms, without worsening of the clinical outcome of these patients. As a possible study endpoint, myocardial perfusion imaging in the acute setting enables the quantification of salvaged myocardium and therefore the evaluation of treatment efficacy. Besides perfusion agents, several infarct avid radiopharmaceuticals have been developed, which in part show promising results. However, larger randomized trials evaluating these tracers in clinical settings are needed to warrant routine clinical application.

Angina, Unstable↗
PubMed2000

Construction and characterization of a catalytic fusion protein system: P-450(11beta)-adrenodoxin reductase-adrenodoxin.

Cortisol is an important intermediate for the production of steroidal drugs and can only be synthesized chemically by rather complicated multi-step procedures. The most critical step is the 11beta-hydroxylation of 11-deoxycortisol, which is catalyzed by a mitochondrial enzyme, P-450(11beta). Various fusion constructs of P-450(11beta) with its electron transfer components, adrenodoxin and adrenodoxin reductase, were produced by cDNA manipulation and were successfully expressed in COS-1 cells from which the hydroxylation activities were assayed. It was demonstrated that the fusion protein required both adrenodoxin reductase and adrenodoxin for its activity and was not able to receive electrons from an external source. The fusion protein with all three components had less activity than P-450(11beta) alone, receiving electrons from coexpressed or internal electron transfer components. The activities of the fusion proteins were determined mainly by the fusion sequence. The fusion protein with a sequence of P-450(11beta)-adrenodoxin reductase-adrenodoxin was more active than that of P-450(11beta)-adrenodoxin-adrenodoxin reductase, 1.5- and 3-fold for bovine and human P-450(11beta), respectively. Modification of the linker region by extending the size of the linker with various peptide sequences in the bovine P-450(11beta)-adrenodoxin reductase-adrenodoxin fusion protein indicated that the linker did not have significant effect on the P-450 activity. Taken together, the fusion protein obtained here can serve as a model for the investigation of electron transfer in P-450 systems and is of potential importance for biotechnological steroid production.

Adrenodoxin↗
PubMed1996

Expression of cytochrome P45011B1 mRNA in the brain of normal and hypertensive transgenic rats.

Cytochrome P45011B1 (11 beta-hydroxylase) was detected in the brain of male rats by in situ hybridization methods. Normal Sprague-Dawley rats were compared to the transgenic strain TGR(mRen2)27, characterized by the expression of the murine Ren-2d renin gene and the development of severe hypertension. Specific riboprobes were generated by in the vitro transcription of a 152 base-pair long cDNA template 35S-labeled riboprobes were hybridized to cryostat sections from adrenal glands and from two different levels of the brain using standard protocols and varying washing conditions. After exposure of the radiolabeled sections to X-ray film, the signals were quantified and compared. Following autoradiography and counterstaining, cytochrome P45011B1 mRNA was clearly localized in the zona fasciculata/reticularis of the adrenal cortex and in distinct layers of the cerebral cortex. High signal densities were obtained in the layers II-IV of the neocortex and in the layer II of the piriform cortex, although the concentrations of cytochrome P45011B1 mRNA were remarkably lower in the central nervous system as compared to adrenal glands. As revealed by the semi-quantitative analysis, there was a slight increase in adrenal 11 beta-hydroxylase mRNA in the transgenic rats, whereas the brain seems to express nearly the same amount of this enzyme in both strains. The cytochrome P45011B1 mRNA expression in distinct cells, probably nerve cells, and especially in regions with high densities of glucocorticoid receptors points to a possible function of brain derived corticosterone in receptor activation.

Adrenal Glands↗
PubMed1995

Zone-specific localization of cytochrome P45011B1 in human adrenal tissue by PCR-derived riboprobes.

Cytochrome P45011B1 (11 beta-hydroxylase) was detected in the human adrenal cortex and in human adenomas by in situ hybridization methods. Specific riboprobes were generated by in vitro transcription of 11 beta-hydroxylase--specific synthetic oligonucleotides with attached T7 and SP6 polymerase promotors. [35S]- and digoxigenin-labeled riboprobes were hybridized to sections of an aldosterone-producing adenoma (APA), the non-tumour portion of the corresponding adrenal gland, and two adenomas not related to hyperaldosteronism using standard protocols and varying washing conditions. After exposure of the radiolabeled sections to X-ray film, the signals were quantified and compared by statistical tests. Following autoradiography or immunohistochemical detection of the digoxigenin cytochrome P45011B1 mRNA was clearly localized in the zona fasciculata/reticularis of non-tumour portion of an human adrenal with an APA. Zona glomerulosa, medulla and connective tissue were free of label. As revealed by the semi-quantitative analysis, 11 beta-hydroxylase mRNA signals in the APA were significantly lower than those in the attached non-tumour portion and the other two adenomas. The results confirm known observations on the occurrence of cytochrome P45011B1 in the adrenal cortex of other species, but show, contrary to several immunohistochemical studies, that the enzyme is obviously not expressed in the zona glomerulosa.

Adenoma↗
PubMed1991

[Is adrenalectomy always advisable in tumor nephrectomy?].

Since the addition of ultrasonography and computerized tomography to the diagnostic tools used for the recognition of renal tumor masses, detection of renal cell carcinomas has been much earlier and more reliable than formerly. Between July 1981 and June 1990, 335 patients without distal metastases underwent radical nephrectomy for renal cell carcinoma. In only 2.6% of the patients were adrenal metastases found, exclusively with stage pT3 tumors. The results of this review suggest that the adrenal gland need not be removed with the radical nephrectomy specimen in the case of tumors staged T1 or T2 if the adrenal CT scan is normal.

Adrenal Gland Neoplasms↗
PubMed1983

Can a substitute for the bladder sphincter be attained by free transplants derived from vesical muscle tissue?

Smooth muscle transplants of the intestinal tract have been tested experimentally as a substitute for the bladder sphincter. An attempt was made to apply the proposed technique to the vesical muscle tissue and to achieve a sphincter replacement with freely transplanted autologous bladder tissue. An internal urethrotomy was performed several times in female sheep until a complete urinary incontinence resulted. For the bladder sphincter substitute a strip of vesical tissue was dissected from the anterior wall and following pre-stretching it was sewed circumferentially around the urethra in order to constrict it. The urethral pressure was registered during the operation before and after application of the sphincter 'graft'. For temporary urinary discharge a suprapubic catheter was inserted. The sheep were examined clinically and urodynamically for up to 3 months. Complete urinary continence was not obtained in any of the cases. The urodynamic examination showed a nearly complete loss of the urethral pressure which had been obtained by the operation. The histological studies showed progressing fibrosis of the desired continence zone. By way of freely transplanted autologous vesical muscle a sphincter substitute could not be achieved.

Animals↗
PubMed1981

Electrohydraulic lithotripsy with aspiration of the fragments under vision--304 consecutive cases.

We herein report on 304 consecutive cases of bladder stones treated by electrohydraulic lithotripsy. The special armamentarium is described. The average age for male patients was 68.5 years, the oldest being 102 years, and for female patients it was 63.9 years. Of the patients 38.5 per cent were high risk. The weight of the transurethrally removed stones ranged from 1 to 135 gm. In 70.4 per cent of the male patients transurethral resection of the prostate was done under the same anesthesia and technical problems were encountered in 12 operations (4 per cent). Bladder perforations occurred in 5 patients but cystotomy and drainage were necessary in only 1 (0.3 per cent).

Adolescent↗
PubMed1981

[Present status of transurethral laser technique in the treatment of urethral strictures (author's transl)].

The main difference between the conventional methods of urethrotomy and the laser method is that the scar tissue of the urethral stricture is not cut but removed by evaporisation. At present only neodymium: YAG and argon ion lasers are available for clinical endoscopic use. For the purpose of removing tissue neodymium: YAG lasers need irrigation with a gas in contrast to argon ion lasers that can be utilized with the well known water irrigation. Certain considerations and experiences suggest the carbon dioxide lasers to be the best ones for evaporating stricture tissue since they cause very limited zones of necrosis with immediate sealing of the wound edges. Transurethral carbon dioxide laser application, however, is still at an experimental stage, since convenient light transmission systems are not available for clinical use at the present time.

Argon↗
PubMed1981

[Canine urethra as a model for experimental studies on urethral strictures (author's transl)].

Of all commonly used laboratory animals, the dog seems especially suited for transurethral experiments on the urethra when using normally available urological instruments. Because of its particular anatomy only the pelvic portion of the urethra in male dogs is available for study. In animals weighing at least 20 kg this segment is wide enough to permit insertion of instruments of up to F 24 size. Anatomically, this segment corresponds to the proximal segment of the bulbous portion of the urethra in man, i.e. there is no corpus cavernosum urethrae surrounding the urethra. Experiments in this segment require a perineal urethrostomy, the construction of which is associated with a high complication rate. The pelvic urethra of the male dog does not differ structurally from that of the female dog. Experiments on the female canine urethra can therefore be performed equally well and with less complications. Urethral strictures can be simply and effectively created by circular transurethral electrocoagulation of the urethral wall. With extensive urethral wall coagulation, temporary complete urinary retention may be observed postoperatively, which is due to extensive edema of the affected area.

Animals↗
PubMed1980

[Juvenile urologic foreign body extraction].

Foreign bodies are rarely found in the urethra and bladder of children. Generally, they are first observed at the start of puberty. Severe complications may occur, even involving the upper urinary tract. Therefore, foreign bodies should be removed as early as possible. Even in infancy it is possible to extract foreign bodies by transurethral approach. When such an extraction is carried out, injuries to the urethra, especially in male children, must be avoided. When difficulties arise during the transurethral procedure suprapubic removal should be preferred. Urinary tract infections which nearly always accompany the presence of foreign bodies in the urinary tract should be treated with antimicrobials.

Adolescent↗
PubMed1979

[Ureteral polyposis].

In connection with a case report a review is given on the clinical aspects of ureteral polyposis. The symptomatology of this condition differs considerably. The most frequent symptom is gross hematuria. Ureteral polyposis will be verified in most cases by a retrograde ureteropyelogram. Resection of the tumor bearing ureteral segment should be performed in order to exclude a malignant tumor.

Adolescent↗
PubMed1979

Transurethral laser urethrotomy in man: preliminary report.

After in vitro and in vivo endoscopic laser investigation on normal and experimentally strictured urethras in dogs transurethral laser urethrotomy was done on men. A neodymium: yttrium aluminum garnet laser with a flexible laser light guide was used. The endoscope developed for this purpose is described in detail. The first laser operations were without complications.

Adult↗
PubMed1979

Present status of endoscopic laser techniques in urology.

Following a brief description of the physical and biomedical characteristics of laser light, a report is given on the development and present status of laser endoscopy in urology. Presently there appear to be two principal indications: i. e. certain bladder tumors and urethral strictures. Neodymium: YAG and argon ion lasers are used for both disorders. The special laser features of these instruments are described.

Carbon Dioxide↗
PubMed1979

Laser investigations of the strictured dog urethra.

The effects of the Neodymium:YAG laser beam on normal as well as on granulation tissue of the dog urethra were investigated in vitro. To determine the effectiveness of the laser beam special attention was paid to the size of the local spot and the pulse duration. After determination of the most favorable diameter of the focus and the pulse duration of the laser beam, endoscopic laser examinations were performed on normal and experimentally strictured urethrae in dogs. A suitable laser endoscope was designed and a surgical technique for laser-beam treatment of the strictured urethra was developed. The postoperative follow-up period was up to 6 weeks. There was no need for postoperative urinary diversion. Neither bleeding nor perforations were observed.

Animals↗
PubMed1978

[Transurethral prostatic resection by cold punch technique. Indication and results (author's transl)].

In men of advancing age benign prostatic hypertrophy is the most frequent cause of obstructive urinary symptoms. Transurethral prostatic resection has been demonstrated as a suitable method to lastingly cure patients with this disease, even if they belong to a high age group or to a so-called high risk group. This report is based on 1490 patients who were operated upon by transurethral prostatic resection utilizing the cold punch technique. The average age was 70.9 years. 5.7% of the patients were 80 years or older. In 38.1% the operative risk was increased. The indication for performing a transurethral prostatic resection is discussed and technical differences between the cold punch technique and the better known electroresection are pointed out. Early and late results as well as complications of the procedure are reported.

Aged↗