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G Bartsch

Publications and source records attributed to G Bartsch.

At least 19 recordsLinked to original sources
PubMed1992

[Anatomy of the posterior urethra].

The short section of the urethra that passes through the urogenital diaphragm is termed the membranous urethra. It is accompanied by several vessels and nerve fibers. In surgery on the membranous urethra the perineal body is of crucial importance, and precise knowledge of the course of the urethra through the pelvic floor is essential. Furthermore, the relationship between the membranous urethra and its accompanying structures is of great importance. These include the branches of the internal pudendal artery, the prostatic venous plexus and the cavernous nerves coursing ventrally from the pelvic plexus. The nerves supplying the membranous urethra were studied in fetuses with the help of a magnifying lens. The results of the dissections are documented by histological sections, photographs and paintings.

Aged↗
PubMed1992

[Urethral rupture--primary repair and reconstruction].

Whether the posterior urethra can successfully be reconstructed depends mainly on the primary care, especially in the case of strictures secondary to trauma. Prior to surgery, primary care of the lesion is mandatory, including open suprapubic fistula, drainage of the cavum retii and of the perineal space, repositioning of the urethra and immediate stabilization of the pelvic ring by means of elastic procedures. In a second step, between 1978 and 1990 we performed bulbo-prostatic surgery in 27 patients with traumatic rupture of the posterior urethra. Based on extensive anatomic be studies on the relationship of the membranous urethra to the pelvic floor and to the arteries, veins and nerves, an operative approach via the perineal body was developed. Of 18 patients followed up, only 4 had flow rates of less than 15 ml/s. Retrograde urethrograms and micturition cystograms showed good results.

Adolescent↗
PubMed1992

Point mutation in the DNA binding domain of the androgen receptor in two families with Reifenstein syndrome.

Inadequate androgen action in genetic and gonadal males causes an intersex phenotype. We have analyzed the androgen receptor (AR) gene in male pseudohermaphrodites with normal specific binding of dihydrotestosterone in their genital skin fibroblasts. In five patients with Reifenstein syndrome we have detected a point mutation in the DNA binding domain. They are from two unrelated families and presented with perineoscrotal hypospadias and undescended testes. After puberty they showed small testes, no palpable prostate, micropenis, azoospermia, and gynecomastia. The mutation was discovered when cDNA fragments from three brothers were sequenced. For rapid detection of the mutation in heterozygous and hemizygous carriers, allele-specific PCRs and restriction-analysis techniques have been developed. Relatives of the patients, a group of normal blood donors, and other patients were screened with these methods. Among 41 intersex patients with incomplete virilization, another two brothers presenting with this mutation were identified. The mutation is a guanine-to-adenine transition at nucleotide 2314, which changes the alanine codon (GCC) immediately after the first cysteine of the second zinc finger motif of the AR into a threonine codon (ACC). The mutation was recreated in an AR expression vector, and wild-type as well as mutant ARs were expressed in COS-7 cells. Cotransfection experiments were made using a mouse mammary tumor virus-chloramphenicol acetyltransferase reporter gene. The ability of the mutant receptor to stimulate transcription of the reporter gene was reduced by about two-thirds, as compared with the wild-type receptor.

Alleles↗
PubMed1992

[Correlation of vesico-ureteral reflux and recurrent urinary tract infections with increased bacterial adherence].

Unimpeded urinary flow and voiding of the bladder without residual urine are essential for the prevention of urinary tract infections. Therefore, recurrent urinary tract infections are most commonly found in patients with functional and anatomic disorders of the urinary tract. Children suffering from vesico-ureteral reflux are especially susceptible to recurrent urinary tract infections. The interaction between germ and target cell, i.e. between antigen and receptor, is another important factor in the development of urinary tract infections. This so-called bacterial adherence is variable and depends upon receptor density as well as the affinity of the germ to the receptor. However, our study showed that this bacterial adherence plays a minor role in the development of recurrent urinary tract infections secondary to vesico-ureteral reflux.

Adolescent↗
PubMed1991

Growth-stimulating effect of adrenal androgens on the R3327 Dunning prostatic carcinoma.

Adrenal androgens are discussed as a reason for tumor progression after androgen ablation therapy. Because of the difference in the secretion of androgens by the adrenals of humans and rats, there is no reliable tumor model to study the role of adrenal androgens in tumor progression. Therefore, the main adrenal androgens were administered to rats in order to mimic human endocrine conditions. Application of dehydroepiandrosteron-sulfate (DHEA-S) alone or a mixture of androstendione (A), 11 beta-hydroxyandrostendione (OHA), dehydroepiandrosterone (DHEA), and its sulfate (DHEA-S) to castrated rats caused only a slight increase of prostate and seminal vesicle weight. Contrary to these findings, growth of the R3327 prostatic carcinoma in castrated rats was greatly stimulated by these adrenal androgens up to the level of the intact control. Thus, in spite of androgen ablation, tumor progression could be induced by exogenous adrenal androgens.

Adenocarcinoma↗
PubMed1991

Megalourethra.

Explore the source record for details and available documents.

Humans↗
PubMed1991

[The potential hormonal therapy of prostatic carcinoma].

Hormonal manipulation is still the most effective systemic treatment for prostate cancer. The alternatives to orchiectomy are discussed: estrogens, with their known cardiovascular side-effects, and the expensive LH-RH analogues and/or antiandrogens, the success of which depends heavily on the patient's compliance. With more intensive health care and more sensitive methods of diagnosis, not only is the overall number of prostate carcinomas diagnosed increasing, but also the percentage that need not be fatal. The timing of hormonal treatment and selection of patients are increasing in importance.

Aged↗
PubMed1991

[Approach to radical cystoprostatectomy].

A new possibility of using a standardized surgical approach is demonstrated by specific topographic-anatomical paintings. The operation, in this case radical cystoprostatectomy and lymphadenectomy in the man is demonstrated in the cadaver, from the incision of the skin to the excision of prostate and bladder. The significant surgical steps are documented in paintings, which allow exact documentation of the anatomical approach.

Cystectomy↗
PubMed1990

Isotachophoretic separation of organic acids in biological fluids.

The operating conditions for the isotachophoretic separation of organic acids were evaluated. At pH values ranging from 2.90 to 4.25 both relative step heights and molar flow-rates were determined experimentally for 26 anions. Comparing the observed values with simulated data, highly significant (p = 0.0001) correlation coefficients of 0.993 and 0.920, respectively, were found at pH 3.50. Whereas the concentration of the leading electrolyte did not affect the relative step heights, it increased the molar flow-rates significantly. The same applied to the detection current. The time of analysis was observed to be a function of the concentration of the leading electrolyte. However, the time elapsed between injection of the analyte and its detection depended solely on the volume and not on the amount of analyte injected. In isotachophoresis, incomplete separation of two compounds is indicated by the occurrence of a mixed zone which can hardly be distinguished from a pure zone. Thus, knowledge of the separation capacity is a prime prerequisite in optimizing the system for the analysis of biological fluids. The separability of nine equimolar pairs of anions was determined at pH values ranging from 2.90 to 4.25. Although two ionogenic constituents would separate only when their migration rates in the mixed state were different, no clear correlation was observed between separation capacity and difference in relative mobility. Separability, however, was found to increase with increasing concentration of the leading electrolyte. While the separation capacity was not influenced by the electric current, it was significantly affected by the volume injected. In subsequent analyses of serum, cerebrospinal fluid, seminal plasma and prostatic fluid, a variety of organic acids could be detected. Calibration graphs for the detected anions revealed a detection limit of 1 nmol and linearity over their biological concentration ranges. Further, the isotachophoretic results correlated well with high-performance liquid chromatographic and enzymatic analyses of citric acid and lactic acid in human seminal plasma and cerebrospinal fluid, respectively.

Acids↗
PubMed1990

Nerve-preserving bilateral retroperitoneal lymphadenectomy: anatomical study and operative approach.

In a study of the sympathetic trunk in 18 cadavers a new anatomical approach for modified bilateral retroperitoneal lymphadenectomy was developed, which is characterized by unilateral preservation of the L3 ganglion and the fibers arising from this ganglion. Furthermore, the sympathetic trunk and its lumbar branches were dissected, including the connections between the right and left sympathetic trunks arising from the L3 and L4 ganglia. On the right side the fibers were found dorsal to the inferior vena cava from where they pass into the aortocaval zone. Caudal to the inferior mesenteric artery these fibers communicate with the left para-aortic fibers. The precise topographic inter-relationship between the L2 and L3 ganglia was studied; the lower margin of the L3 ganglion was located 1 cm. cranial to the origin of the inferior mesenteric artery. Based on these findings a modified operative technique was developed for stages B1 and B2 testicular tumors. With the help of this modification it should be possible to preserve ejaculatory function in 50% of the patients who undergo an operation for small retroperitoneal tumors. However, this modification can be justified only if the recurrence rate is not higher than that with radical bilateral lymphadenectomy.

Adrenergic Fibers↗
PubMed1989

[Benign prostatic hyperplasia: a stromal disease].

Morphometric studies show that benign human prostatic hyperplasia is a stromal disease caused by the activation of smooth muscle cells. This activation manifests itself in increased amounts of cytoplasmic organelles, which are preferably localized in the perinuclear region. Moreover, marked vesicular activity is present. Besides considerable overproduction of type I and III collagens, the architecture of the extracellular matrix is altered distinctly. In spite of strong evidence that androgens and estrogens regulate the growth of epithelial and stromal cells in the prostate and the induction of fibromuscular overgrowth in various animal models, the exact role of steroids in the pathogenesis of benign prostatic hyperplasia still remains to be elucidated.

Androgens↗
PubMed1989

The National Marrow Donor Program: how it works, accomplishments to date.

As the use of bone marrow transplantation increases, the lack of a suitable matched sibling donor for approximately 60% of patients is a growing problem. Recently, marrow transplantation has been done successfully using HLA-matched unrelated donors. In an effort to provide more donors, the National Marrow Donor Program (NMDP) was established. It involves 50 blood banks and 20 marrow transplant centers throughout the United States. More than 20,000 HLA-typed apheresis donors from these blood banks have agreed to be listed in the NMDP registry. A preliminary search for donors has been carried out for 1,116 patients. Donors suitably matched for HLA-A and B antigens were located for 99% of the patients.

Bone Marrow Transplantation↗
PubMed1988

Transrectal ultrasonography as a follow-up method in prostatic carcinoma after external beam and interstitial radiotherapy.

Transrectal ultrasonography and ultrasonometrics were employed for follow-up in a total of 28 prostatic carcinoma patients subjected to external beam or interstitial radiotherapy. These two methods permit more accurate staging of prostatic carcinoma and have also proved to be valuable in the follow-up care of patients suffering from locoregional prostatic carcinoma. Of the 20 patients subjected to external beam radiotherapy four patients initially did not show capsular infiltration, 2B2, 2A2, whereas 16 patients presented with infiltration of the capsule and seminal vesicles. After external beam radiotherapy the ultrasonomorphologic findings of four patients revealed a sharply demarcated capsule and unremarkable seminal vesicles, which indicated tumour regression. Of five patients with infiltration of the pelvic floor and/or seminal vesicles, three showed definite tumour regression, whereas the ultrasonograms of the other two patients demonstrated tumour progression despite radiotherapy. In eight patients the greatest reduction in tumour volume was found one year after interstitial radiotherapy. Only one patient, initially presenting with slight infiltration of the capsule, was shown to have infiltration of the capsule and seminal vesicles after interstitial radiotherapy. At follow-up, evaluation of the echo patterns in these patients was inaccurate on account of the dense echoes reflected by the seeds implanted.

Brachytherapy↗
PubMed1987

Unilateral testicular disease: effect on the contralateral testis (morphometric study).

Unilateral testicular disease has been reported to damage the contralateral testis. In order to find out whether this detrimental influence is permanent in nature or can be avoided by therapeutic measures, and furthermore to quantify the damage, the following experiments were performed. Seventy-five rats were classified into the following five groups: I) testicular torsion persisting for eight hours; II) ipsilateral semicastration after torsion persisting for eight hours; III) semicastration; IV) sham operation as control; V) immunosuppression with azathioprine after torsion persisting for eight hours. The contralateral testes were removed two months later and perfused with fixative via the testicular artery. Stereologic techniques were employed to obtain quantitative morphologic data. Serum hormone levels were determined. The volume density of the contralateral germinal epithelium was not decreased two months after torsion for eight hours, torsion following by semicastration or torsion followed by immunosuppression. The same was true of the total volume of germinal epithelium per rat testis. The hormone levels remained essentially unchanged.

Animals↗
PubMed1987

Light-microscopic stereologic analysis of spontaneous and steroid-induced canine prostatic hyperplasia.

A combined light-microscopic and stereologic analysis of the canine prostate was performed under the following experimental conditions: intact and castrated dogs, spontaneous benign prostatic hyperplasia, intact and castrated dogs after treatment with testosterone, 5 alpha-dihydrotestosterone or 3 alpha-androstanediol in combination with estradiol. Regarding the absolute amounts of the glandular and stromal parts of the prostate as well as the glandular cells, no difference was found among the testosterone, 3 alpha-androstanediol and 5 alpha-dihydrotestosterone treated castrated dogs. Treatment with 5 alpha-dihydrotestosterone or 3 alpha-androstanediol in combination with 17 beta-estradiol induced a four-fold increase in glandular and a two-fold increase in stromal tissue. The glandular to stromal tissue ratio equals that found in spontaneous canine hyperplasia, which is indicative of the glandular type of spontaneous canine hyperplasia. Therefore, it can be stated that treatment with 5 alpha-dihydrotestosterone or 3 alpha-androstanediol combined with 17 beta-estradiol not only induces prostatic overgrowth but also leads to prostatic hyperplasia of the glandular type. However, the stereologic analysis of canine prostates following steroid administration shows that canine hyperplasia is primarily a glandular disease, while human benign prostatic hyperplasia shows more stromal activation.

Androstane-3,17-diol↗
PubMed1987

Correlation of biochemical (receptors, endogenous tissue hormones) and quantitative morphologic (stereologic) findings in normal and hyperplastic human prostates.

In previous light and electron-microscopic analyses human benign prostatic hyperplasia was shown to be predominantly a stromal disease; the aim of the present study was to correlate the stereological data with the levels of the endogenous tissue hormones (androgens, estrogens, progesterone) in normal (N) and hyperplastic human prostatic tissues (BPH). BPH tissue specimens were obtained by open prostatectomy (n = 25); normal prostatic tissue was obtained from kidney donors (n = 5). No statistically significant difference was found between normal and hyperplastic tissue. Testosterone BPH 0.69 +/- 0.44, N 0.25 +/- 0.12; 5 alpha-dihydrotestosterone BPH 7.0 +/- 2.9, N 4.2 +/- 0.7; progesterone BPH 0.059 +/- 0.022, N 0.058 +/- 0.005; estrone BPH 0.10 +/- 0.03, N 0.14 +/- 0.03; estradiol BPH 0.07 +/- 0.02, N 0.05 +/- 0.02; estriol BPH 0.02 +/- 0.01, N 0.04 +/- 0.02. Using a Spearman rank correlation coefficient a statistical analysis was performed for age, weight of the prostate, absolute stereological data and the endogenous prostatic hormones. As can be seen from the statistical analysis there is a poor correlation for 5 alpha-dihydrotestosterone and the amount of the glandular epithelium; otherwise no correlation of the endogenous tissue hormones with the stereological data investigated was found. These data show that the stromal overgrowth of benign hyperplasia is not reflected in the tissue hormone levels.

Gonadal Steroid Hormones↗