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Dirk Schultheiss

Publications and source records attributed to Dirk Schultheiss.

15 recordsLinked to original sources
PubMed2006

Early photo-illustration of a hermaphrodite by the French photographer and artist Nadar in 1860.

As early as 1860 the French photographer Gaspard Félix Tournachon, called Nadar (1820-1910), took a series of nine photographs depicting a young intersex patient. These illustrations were not published at their time and little is known about the patient and the role of the physicians involved in this case. The article discusses the available information on these artworks that today belong to the photographic collection of the Musée d'Orsay in Paris.

Disorders of Sex Development↗
PubMed2005

Isolation of primary endothelial and stromal cell cultures of the corpus cavernosum penis for basic research and tissue engineering.

OBJECTIVES: Primary cell cultures derived from the corpus cavernosum are frequently used as in vitro models to define cellular mechanisms involved in erectile function. However, previous studies often lack detailed isolation protocols or a precise characterisation of the culture composition excluding especially contaminating fibroblasts. This study aimed at critically analysing and reproducing reported isolation methods, as well as establishing new procedures to receive highly pure and morphologically differentiated endothelial, smooth muscle and fibroblastic cells derived from the human penis. METHODS: We evaluated numerous isolation and enrichment techniques using cavernosal tissue from 57 patients. Assessment factors displayed the purity, cell yield, practicability and reproducibility. The purity in cultured cells was analysed using immunocytochemistry and Western blots. RESULTS: An enzymatic protocol was established for the isolation and cultivation of cavernosal endothelial cells with an impressive purity of 98.0+/-0.8%. In contrast, already published nearly pure smooth muscle cell cultures were not reproducible in our laboratory. Meaningful evidence for an overwhelming presence of fibroblasts in these widely accepted pure smooth muscle cell cultures is presented. CONCLUSION: Endothelial cell cultures derived from human corpora cavernosa are reproducible and reliable to serve for cell culture-based investigations of the endothelial dysfunction. The discrepancy in the purity of smooth muscle cell cultures might reflect laboratory and tissue source factors, lacking an exclusion of fibroblasts in other studies or changes in stromal phenotype under culture conditions. Further research is necessary to clarify a possible plasticity between smooth muscle cells and (myo)fibroblasts and assess functional properties.

Adult↗
PubMed2005

Biological vascularized matrix for bladder tissue engineering: matrix preparation, reseeding technique and short-term implantation in a porcine model.

PURPOSE: We generated a vascularized, autologous, reseeded bladder substitute and evaluated immediate vascularization and perfusion of the graft after implantation to the recipient organism in a porcine model. MATERIAL AND METHODS: Acellular matrix was processed from porcine small bowel segments by subsequent mechanical, chemical and enzymatic decellularization, preserving the jejunal arteriovenous pedicles. In 2 separate steps the matrix was reseeded with primary bladder smooth muscle cells (SMCs) and urothelial cells (UCs), and its vascular structures were resurfaced with endothelial progenitor cells (EPCs). To evaluate graft perfusion short-term implantation was performed. RESULTS: The acellular scaffold was successfully repopulated with multilayers of ingrowing SMCs and superficial UCs. After reseeding the jejunal arteriovenous pedicles with EPCs and cultivation for 3 weeks the larger vessels as well as the intramural scaffold capillary network were repopulated with cell monolayers expressing endothelial specific proteins. Perfusion stagnation and implant thrombosis occurred within 30 minutes after the implantation of acellular scaffolds not reseeded with EPCs. In the EPC reseeded group the vascular system revealed intact perfusion and no relevant thrombus formation was observed after 1 or 3 hours. CONCLUSIONS: The current study of successful SMC and UC reseeding, vessel resurfacing with EPCs and short-term vascular patency represents the promising in vitro and in vivo basis for further evaluation of this biological vascularized matrix in chronic long-term large animal implantation experiments.

Animals↗
PubMed2005

In vitro viability of human cavernosal endothelial and fibroblastic cells after exposure to papaverine/phentolamine and prostaglandin E1.

OBJECTIVE: To investigate the influence of commercially available vasoactive drugs on human cavernosal endothelial and fibroblastic cells in vitro, as although corporal fibrosis is a well known side-effect of intracavernosal injection therapy for erectile dysfunction, the possible detrimental effect of these agents on the endothelium lining the cavernosal vascular spaces is uncertain. MATERIALS AND METHODS: Cultured primary endothelial (13) and fibroblastic cells (12), obtained from potent patients undergoing penile surgery, were exposed to different physiological dilutions of prostaglandin E1 (PGE1), papaverine/phentolamine or the respective triple-mix of these agents for 30 min. Viable cells were counted and cell metabolic activity measured in these cultures 48 h after drug exposure. RESULTS: There was a significant dose-dependent decrease in the viable cell count after exposure to papaverine-containing formulations, probably because of the low pH of this substance. This cytotoxic effect was more pronounced in endothelial than in fibroblastic cells, and was not apparent in the PGE1 groups. The relative increase in cell metabolic activity in cultures affected by a moderate cytotoxic effect indicated a regenerative process. CONCLUSION: These comparative results in endothelial and fibroblastic cell cultures suggest that the endothelium rather than the interstitium of the corpus cavernosum is more sensitive to side-effects produced by intracavernosal injection therapy with papaverine. Thus, unfavourable consequences on the function of the endothelial layer might be as important as the risk of interstitial fibrosis. As these effects were not detected for PGE1 this drug should be preferred to papaverine in clinical practice.

Alprostadil↗
PubMed2005

Nikolaj A. Bogoraz (1874-1952): pioneer of phalloplasty and penile implant surgery.

Phalloplasty and penile implants are outstanding pioneering procedures introduced in 1936 by the Russian surgeon Nikolaj A. Bogoraz and are thus of eminent interest to the urological and plastic surgeon. This article from the history of medicine will discuss his biography and scientific achievements during the first half of the 20th century.

History, 20th Century↗
PubMed2004

Functional tissue engineering of autologous tunica albuginea: a possible graft for Peyronie's disease surgery.

OBJECTIVES: The aim of the present study was to generate a tissue engineered type of mechanically stable graft suitable for surgical replacement of the tunica albuginea penis. METHODS: Porcine fibroblasts isolated from open fascia biopsies were seeded on decellularized collagen matrices and then cultivated in a bioreactor under continuous multiaxial stress for up to 21 days (n=12). Static cultures without mechanical stress served as controls. Cell proliferation, cell alignment, and de novo synthesis of extracellular matrix proteins (proteoglycans, procollagen I, elastin) in these grafts was evaluated by hematoxylin-eosin, pentachrome, and immuno-staining. Additionally, the enzymatic isolation of porcine fibroblasts from X4mm skin punch biopsies (n=8) was evaluated. RESULTS: Mechanically strained cultures of fibroblasts showed a homogeneous multilayer matrix infiltration and a regular cell alignment in the direction of strain axis after 7 days, as well as a de novo production of extracellular matrix proteins compared to the static control. A large amount of viable fibroblasts was easily obtained from small skin punch biopsies. CONCLUSION: This study shows that continuous multiaxial stimuli improve proliferation and extracellular matrix synthesis of mature fibroblasts reseeded on a biological matrix making this a feasible autologous tissue engineered graft for penile surgery. For the clinical setting fibroblasts harvested from small skin biopsies can be a comfortable cell source.

Animals↗
PubMed2004

Regenerative medicine in andrology: Tissue engineering and gene therapy as potential treatment options for penile deformations and erectile dysfunction.

Tissue engineering and gene therapy are currently investigated in animal studies for reconstructing penile tissue or treating erectile dysfunction. This review aims to examine these experimental efforts from the last years and tries to give a brief introduction to the basic methodology of these new techniques from the field of regenerative medicine.

Andrology↗
PubMed2004

Cytotoxicity of different intracavernous vasoactive drugs on cultured endothelial cells of human corpus cavernosum penis.

OBJECTIVES: To investigate the cytotoxic effect of prostaglandin E(1) (PGE(1)), a standard combination of papaverine/phentolamine, and a triple mixture of these agents on human cavernosal endothelial cells using a cell culture model. The endothelial layer of the corpus cavernosum plays an important role in signal transduction of penile erection and is directly exposed to vasoactive agents after intracavernous injection for erectile dysfunction. METHODS: Primary endothelial cells were obtained from the corpus cavernosum of 13 potent patients undergoing penile surgery. Cultured cells were exposed for 30 minutes to physiologic dilutions of 20 microg PGE(1), 30 mg papaverine/1 mg phentolamine, or the same dosages of the triple mixture of these agents, each dissolved in 5 to 50 mL sodium chloride. Lactate dehydrogenase release as a cytotoxicity marker was measured 6 hours after drug exposure, and the total cell metabolic activity was quantified after 48 hours with a 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxy-phenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS)-based assay. Additionally, the amount of viable cells was identified with a dual fluorescent staining procedure. RESULTS: The initial release of lactate dehydrogenase was elevated up to 3.2-fold in the concentrated papaverine/phentolamine and triple mixture group compared with PGE(1) and the control. After 48 hours, the papaverine-containing formulations led to a significant dose-dependent decrease in the viable cell count and metabolic activity of the cultures that was not noticed with PGE(1). CONCLUSIONS: These in vitro data strongly suggest an unfavorable effect of vasoactive agents containing papaverine on cavernosal endothelial cells. Before fibrotic changes of the smooth muscle stroma, the functionally important endothelium of the corpus cavernosum might suffer significantly from intracavernous injection therapy. Therefore, papaverine should no longer be used for this indication.

Alprostadil↗
PubMed2004

The penile implant for erectile dysfunction.

INTRODUCTION: Penile prostheses, introduced as the first effective organic treatment for erectile dysfunction over three decades ago, have an important role in the treatment of erectile dysfunction when other nonprosthetic treatment options have proven unsatisfactory. Although they are the least chosen and most invasive treatment option, they have the highest satisfaction rate of all available ED options and provide a predictable and reliable result. AIM: To provide recommendations/guidelines concerning state-of-the-art knowledge for utilization of the penile prosthesis in the management of men with erectile dysfunction. METHODS: An International Consultation in collaboration with the major sexual medicine associations assembled over 200 multidisciplinary experts from 60 countries into 17 committees. Committee members established specific objectives and scopes for various sexual medicine topics. The recommendations concerning state-of-the-art knowledge in the respective sexual medicine topic represent the opinion of experts from five continents developed in a process over a 2-year period. There were 10 experts from seven countries concerning the Penile Implant for Erectile Dysfunction. MAIN OUTCOME MEASURE: Expert opinion was based on grading of evidence-based medical literature, widespread internal committee discussion, public presentation and debate. RESULTS: Recommendations/guidelines for penile prosthesis (hydraulic, semi-rigid and soft silicone) insertion for management of men with erectile dysfunction were updated. Consensed issues included: criteria for patient selection, informed consent procedures, strategies for preoperative preparation, operative incisions/technical considerations and outcome results in terms of patient satisfaction and device survival. Updated information was reviewed concerning therapies for device failures, device insertion in scarred corporal bodies and strategies for managing implant infections. CONCLUSIONS: There is a need for more research in developing management strategies for insertion of penile prostheses in men with ED.

Consensus↗
PubMed2004

The Stromeyer hook--life and work of the man behind the eponym.

Georg Friedrich Stromeyer (1804-1876) is generally known as one of the founders of orthopedics and orthopedic surgery and a pioneer of modern military medicine. Every oral maxillofacial surgeon in Germany knows him because of the "Stromeyer hook" for the elevation of zygomatic arch fractures. The present paper focuses on this particular aspect of maxillofacial surgery as well as on Stromeyer's biography.

Germany↗
PubMed2003

G. Frank Lydston (1858-1923) revisited: androgen therapy by testicular implantation in the early twentieth century.

At the beginning of the twentieth century the transplantation or implantation of either human or animal testicular tissue was an appealing form of androgen therapy in hypogonadal and aging males. This article on the history of medicine discusses the work of the American urologist G. Frank Lydston from Chicago, who was a well-known and respected surgeon in the academic world and was involved in the early clinical trials of this procedure.

Androgens↗
PubMed2003

Androgen and estrogen receptors in the human corpus cavernosum penis: immunohistochemical and cell culture results.

Despite the central and peripheral effects of androgens on the nervous system, the local effects of androgens in the corpus cavernosum penis and their importance for erectile function is still unclear. In this study corpus cavernosum biopsies of eight adult potent patients, aged 19-63 years, undergoing penile deviation surgery (group A) and 12 patients undergoing male-to-female transsexual surgery (group B) were immunostained for nuclear androgen and estrogen-alpha receptors. Additionally, primary corpus cavernosum endothelial cell cultures were obtained from six transsexual patients and exposed to testosterone, dihydrotestosterone, estradiol and progesterone likewise for 7 days. Total cell count was performed and cell metabolic activity was measured by a tetrazolium salt-based assay. Androgen and estrogen-alpha receptors were detected in stromal as well as in endothelial cells. Of all cell nuclei, 74.9% (SD 16.4) in group A and 63.5% (SD 17.1) in group B were positively stained for androgen receptors. The respective percentage of estrogen receptors was 11% (SD 9.5) and 21.2% (SD 12.6). An age-dependent difference in receptor distribution was not observed in either group. In the cell culture system only cultures exposed to testosterone and dihydrotestosterone showed a dose-dependent increase of cell metabolic activity compared to the cultures supplemented with estradiol and progesterone. The significant and age-independent high androgen and low estrogen-alpha receptor distribution found in both groups suggests a possible peripheral effect of androgens at the level of the corpus cavernosum penis in adult humans. This is supported by the observed effect of testosterone and dihydrotestosterone on cell count and endothelial cell metabolism in our cell culture system. The role of estrogens remains unclear.

Adult↗
PubMed2002

Johann Friedrich Dieffenbach (1792-1847) pioneer in oral maxillofacial surgery.

After Carl Ferdinand von Graefe laid down the principles of rhinoplasty and related operations it was Johann Friedrich Dieffenbach (1792-1847) who became a pioneer of plastic surgery in the 19th century. His biography and scientific work with emphasis on craniofacial surgery are presented in this article on the history of medicine.

Germany↗