Sabine Löffler

Comparative anatomical measurements of osseous structures in the ovine and human knee

The ovine stifle has been increasingly used as a large animal model for the human knee. Still, comparative anatomical measurements of the knee in sheep and humans are missing. Thus, the purpose of this study was to describe and measure the osseous anatomy of the ovine stifle in comparison to the human knee. Twenty-four stifles of skeletal-mature merino-sheep and 24 human cadaver knees were obtained and distances between selected anatomical structures of the distal femur, the proximal tibia, and the patella were measured digitally and documented. Based on these, intercondylar ratio, tibial aspect ratio, patella aspect ratio and the cortical index were calculated. Regarding epicondylar width, lateral condylar width, medial condylar width and the tibial dimensions, the ovine stifle can be considered as a human knee scaled down by one third. However, sheep have a smaller trochlear width and a narrower femoral intercondylar notch than humans resulting in lower relative values for intercondylar width and intercondylar height. The distal femurs cortical index is the same in both species. In contrast, sheep have a massive bone stock below their tibial plateau and a proximal tibial shaft with remarkably thick cortical bone. The ovine stifle can be regarded as a useful model for the human knee. However, future studies should consider the differences in the femoral intercondylar notch width, the patellofemoral joints biomechanics and the proximal tibias cortical bone stock.

Ethanol-glycerin fixation with thymol conservation: A potential alternative to formaldehyde and phenol embalming

Anatomical fixation and conservation are required to prevent specimens from undergoing autolysis and decomposition. While fixation is the primary arrest of the structures responsible for autolysis and decomposition, conservation preserves the state of fixation. Although commonly used, formaldehyde has been classified as carcinogenic to humans. For this reason, an adequate substitute was developed. Ethanol‐glycerin fixation and thymol conservation are described and compared with formaldehyde and phenol in this technical report. The setup, tissue qualities, financial aspects, and health concerns of this method are discussed. Ethanol‐glycerin fixation and thymol conservation provide outstanding haptic and optic tissue qualities. Typical formaldehyde and phenol effects, such as skin, airway, and eye irritation, as well as carcinogenic effects, can be circumvented by using ethanol‐glycerin and thymol instead. Ethanol‐glycerin fixation is more expensive than formaldehyde and requires an explosion‐proof facility. However, the absence of health effects and its convincing tissue qualities balance these higher costs. Therefore, ethanol‐glycerin fixation and thymol conservation provide a potential alternative and complement established fixation techniques. The use of carcinogenic formaldehyde and toxic phenol can be effectively restricted through the use of the described method. Anat Sci Educ.

The transient disappearance of cytokeratin in human fetal and adult ovaries

Cells from the inner and outer granulosa cell layers of the ovarian follicles differ in function, probably because of their different origins from the surface epithelium and from the rete. This suggestion has not so far been thoroughly investigated in the human ovary. We examined fetal ovaries from the early, middle and late gestational periods, ovaries from fertile women, and preovulatory follicular cells obtained from patients under in vitro fertilization therapy (IVF). Indirect immunohistology and immunocytology were used to detect the presence of cytokeratin (CK)-positive epithelial cells. In fetal ovaries from the early gestational period, prominent rete tubules (sometimes with oocytes) appeared to be fused with the sex cords and primordial follicles. Both showed CK-positively, detected with the pan-CK antibody Lu-5. Cytokeratin 19 was clearly expressed in the fusion area. In the fetal and adult ovaries, CK-positive follicular or granulosa cells were noted in the primordial and primary follicles as well as the preovulatory follicles. Cytokeratin was not detected in the granulosa cells of growing follicles, CK-positive and -negative luteal cells were identified in the developing corpus luteum. We conclude for the human ovary: (1) the heterogeneous morphology of granulosa cells may be explained by their twofold origin from the surface epithelium and the rete, (2) the rete tubules appear to be involved in folliculogenesis, (3) the transient absence of CK expression in growing follicles compared to resting and mature follicles or to the developing corpus luteum indicates a particular role of CK-positive cells at the periovulatory period.

Coexpression of preprotachykinin A and B transcripts in the bovine corpus luteum and evidence for functional neurokinin receptor activity in luteal endothelial cells and ovarian macrophages

Nonneuronal cell sources of tachykinins, such as substance P (SP) and neurokinin B (NKB), have been demonstrated in leukocytes, endothelial cells and endocrine cells, and may play a role in corpus luteum (CL) development. For this reason, we analyzed mRNA presence for the two tachykinin precursors together with the neurokinin-1 receptor and the neurokinin-3 receptor (NK-1R and NK-3R, preferred by SP and NKB, respectively) in bovine CL at various stages in the luteal phase. Using the RT-PCR technique, we detected coexpression for the preprotachykinin A gene (PPT-A), which encodes SP and neurokinin A (NKA), and the preprotachykinin B gene (PPT-B) for NKB in the CL at the development, secretion and regression stages. Coexpression was also noted for NK-1R and NK-3R gene transcripts. Cultures of endothelial cells (ECs) derived from bovine CL expressed NK-1R and NK-3R mRNA, as did ovarian macrophages. Agonist treatment induced a stronger intracellular calcium ([Ca2+]i) increase after activation of NK-1R compared to NK-3R, a result that we verified by calcium imaging. This is the first evidence for functional tachykinin receptor activity in luteal ECs and ovarian macrophages from bovine CL.

Comparison of modified Thiel embalming and ethanol-glycerin fixation in an anatomy environment: Potentials and limitations of two complementary techniques.

Thiel‐fixed specimens have outstandingly lifelike visual and haptic properties. However, the original Thiel method is expensive and requires an elaborate setup. It is therefore of principal interest to modify the Thiel method in order to make it available to a broader user group. A modified Thiel embalming method will be described in detail and compared to ethanol‐glycerin fixation with the help of illustrative examples. The visual properties, haptic properties, the usability for performing histological investigations, costs and potential health aspects will be considered. Tissues fixed with the modified Thiel technique gave results similar to the original method, providing more realistic visual and haptic properties than ethanol‐glycerin embalming. However, Thiel fixation is significantly more expensive and requires more precautions to minimize potential health hazards than ethanol‐glycerin‐fixed tissues. In contrast to ethanol‐glycerin‐fixed specimens, the Thiel‐fixed specimens are not suitable for histological investigations. Both modes of fixation are inappropriate for biomechanical testing. Modified Thiel embalming simplifies the availability of body donors with lifelike properties and has cost‐saving advantages to the original technique. Thiel‐embalmed body donors are ideally suited for clinical workshops but have restrictions for student dissection courses in facilities with limited storage space, air circulation or technical staff. Vice versa, ethanol‐glycerin‐fixed body donors are well suited for student dissection courses in such an environment but are limited in their use for clinical workshops. Modified Thiel embalming therefore ideally complements ethanol‐glycerin fixation in order to provide customized solutions for clinical workshops and student dissection courses in a wide range of applications. Anat Sci Educ 8: 74–85.

Neuroanatomy of the male pelvis in respect to radical prostatectomy including three-dimensional visualization

The neuroanatomical structures of the radical prostatectomy (RP) are extensively discussed for their existence, localization and function. Especially structures, e.g. the so‐called neurovascular bundle (NVB) that are points of debate in numerous anatomical studies. We review the literature and present our observations in cadaveric specimens, to reconstruct neuroanatomical structures in three dimensions (3D) with the use of appropriate computer applications and produce images of operative fields. We used an internet PubMed survey (http://www.ncbi.nlm.nih.gov) to review recent publications and included back copies of historical neuroanatomical studies from our own library. Our own experimental cadaveric (specimens preserved in Thiel’s solution) studies of the autonomic nerve supply of the lower urinary tract were also reviewed. Visualization of the pelvic anatomy and neuroanatomy was done using computer‐based software packages. No unified terminology for the structures of the NVBs can be presented to date. The innervation of the smooth muscular structures of the urethra and the complex morphology of urethral sphincter remain unclear. Our cadaveric studies showed that nerves are located on the lateral aspect of the prostate in addition to the NVBs described at the dorsolateral side of the prostate. The neuroanatomical investigations of the male pelvis and visualization of the structures in 3D enable the presentation of operative sites as seen intraoperatively. Moreover, dynamic depiction of the pelvic floor is also possible.

Substitution of Formaldehyde in Cross Anatomy Is Possible

The recent publication by Hauptmann et al. (1) in the Journal provided clear evidence for increased mortality from cancer induced by exposure to formalin, as outlined by The Final Report on Carcinogens Background Document for Formaldehyde of the National Toxicology Program (2). Hauptmanns data, along with a report by Figure 1. A–C) Examples of ethanol-and glycerin-fixed human tissue specimens are shown. A) The Erbs punctum nervo-sum (asterisk) is depicted in the lateral view of a dissected neck. Note the vivid color of the underlying sternocleidomas-toid muscle (M). C = clavicula, D = deltoid muscle, G = great auricular nerve, Pg = parotid gland, S = supraclavicular nerves, T = transverse cervical nerve. Specimen was fixed for 12 months before picture was taken. B) The opened left ventricle shows the aortic valve (V), the papillary muscles (P), and the ostia to the left coronary artery (Ol) and to the right coronary artery (Or). A = aorta, Ct = chordae ten-dineae, L = left ventricular myocardium, Tc = trabeculae carneae. Specimen was fixed for 15 months before picture was taken. C) The situs thoracis with peri-cardium (Pc), lungs (Ld = Lobus dexter, Ls = Lobus sinister), and phrenic nerve (Pn). Note the preservation of the neuro-vascular bundle of the ventral medias-tinum (Pv = pericardiacophrenic vessels). A = aorta, Iv = internal thoracic vessels, Vs = superior vena cava, Tp = truncus pulmonalis. The specimen was fixed for 12 months before picture was taken. Viegas et al. (3) demonstrating that medical students are exposed to formalin concentrations greater than 5 ppm during macro-scopic examinations, have caused medical institutions to reconsider the use of for-malin to fix and preserve cadavers and tissues. The emerging data indicating the toxicity of formalin have resulted in the closure of German dissecting rooms in medical schools and could potentially result in poor gross anatomy training and strongly affect the quality of medical staff education. A recent complaint by surgeons that a lack of knowledge in anatomy is already prevalent among young doctors (4) indicates that the development of new nontoxic fixatives are necessary to allow medical students to adequately study gross anatomy in a safe environment. To address this problem, the Institute of Anatomy at Universität Leipzig has developed an approach to conserve human cadavers for dissection courses with the use of a fixative consisting mainly of eth-anol and glycerin. This room temperature 1.5% glycerin solution is perfused …

KIT receptor-positive cells in the bovine corpus luteum are primarily theca-derived small luteal cells

The tyrosine kinase KIT receptor, the protooncogene CD117, plays a key role in growth and maturation of oocytes and follicles. Relevant data are sparse for the corpus luteum (CL). We first confirmed the presence of KIT mRNA and KIT protein in bovine CL homogenates. We then localized KIT-positive (KIT+) cells in CL sections by immunohistochemistry. At the CL stage of early development, the former theca transforming into capsule/septa showed a strong band-like KIT+ immunoresponse. In addition, CD45+ leukocytes in septa included subpopulations of CD45+/KIT+ and CD14+/KIT+ leukocytes as validated by double immunofluorescence localization. At the early secretory stage, KIT+ cells appeared within the septa/capsule region and in the periphery of the CL parenchyma, there forming a complex network. This was separate from the capillary bed as determined by double staining for CD117 and FVIII-related endothelial cell antigen (FVIIIr). The KIT+ network coincided with cells positive for cytochrome P450 17alpha-hydroxylase, a thecal cell-specific enzyme. The late secretory stage was defined by an advanced manifestation of the KIT+ network in the CL periphery. At the stage of regression, the KIT+ network was absent. The CL of pregnancy expressed high levels of KIT mRNA and KIT protein uniformly throughout pregnancy. The KIT+ immunolocalization revealed small fibroblast-like cells, luteal cells with granules, and clusters of large luteal cells with staining of the cell membrane. We conclude that a majority of KIT+ cells in the bovine CL are primarily theca-derived small luteal cells, and that a minority represent KIT+ leukocytes, in some cases KIT+ monocytes.

Transcripts of neurokinin B and neurokinin 3 receptor in superovulated rat ovaries and increased number of corpora lutea as a non-specific effect of intraperitoneal agonist application.

Neurokinin B (NKB), a member of the tachykinin family, and its neurokinin 3 receptor (NK3-R) are preferentially found in the central nervous system. Others have recently reported on mRNA from this ligand-receptor system in the uterus and on NK3-R expression increasing with age. NKB and NK3-R mRNAs have also been noted in cumulus cells and oocytes from superovulated rats. Intact ovaries before and after puberty have not been studied. In this study, we stimulated 29-day-old rats by s.c. injections with gonadotropins for estrous cycle synchronization in order to elucidate the NKB-NK3-R systems expression and function in the ovary. Simultaneously, NaCl, the NK3-R agonist (Pro(7))-NKB, the antagonist SB 218795, or thiorphan, a neutral endopeptidase inhibitor of tachykinin degradation, were injected intraperitoneally (i.p.) for 3 1/2 consecutive days. First, we demonstrated NKB and NK3-R transcripts in one rat ovary by RT-PCR. No significant mRNA differences were noted between immature ovaries and superovulated ovaries in any of the i.p. applications. Second, the possible role of NK3-R on the ovulatory process was verified by counting corpora lutea (CL) and CL cysts in serial sections of the other ovary derived from the four different groups and embedded in paraffin wax. CL and CL cysts were noted in greater numbers in the pharmacologically treated groups than in the saline-treated group. To validate possible drug effects on the peritoneum, we additionally studied pieces of the omentum majus and retroperitoneal fat tissue. Both tissues were heavily infiltrated by granulocytes similar to a non-specific inflammatory response. The saline-treated group as well as the pharmacologically treated groups appeared to develop this unexpected side effect to a similar degree. We conclude that transcripts of NKB and NK3-R are present before and after puberty in the rat ovary and appear to be expressed at similar levels which may indicate a role for the NKB-NK3-R system in follicle growth. The effect of increased CL formation after application of the NK3-R agonist i.p. is related to a non-specific response.

Functional anatomy of the male continence mechanism

ZusammenfassungDie anatomischen und funktionellen Grundlagen der Harnkontinenz sind beim Mann weniger gut erforscht als bei der Frau. Insbesondere das Zusammenwirken der einzelnen Komponenten und die dynamische Verankerung im Beckenboden bedürfen einer neuen anatomisch-funktionellen Interpretation, um an der Physiologie des Blasenhalses orientierende Therapieansätze generieren zu können.Der Fokus anatomischer Untersuchungen sollte daher neben dem Externus als Hauptmuskel für den Harnröhrenverschluss auch auf den glattmuskulären (Internus, der innere Anteil des Externus, die urethrale Längsmuskulatur, Elemente des Centrum tendineums und des ventralen Suspensionsapparates), bindegewebigen und nervalen Strukturen liegen. Der die Position des Blasenhalses fixierende ventrale Suspensionsapparat scheint dabei für die Kontinenz und Miktionseinleitung von besonderer Bedeutung zu sein. Diese neuen Erkenntnisse implizieren wie bei der Frau ein integrales Konzept. Ein erster Schritt hierzu wäre eine einheitliche und aktualisierte anatomische Nomenklatur.AbstractThe basic structures and organs contributing to continence in men are far less well investigated than in women. This concerns anatomical and functional aspects as well. Especially the cooperation of single components and the dynamic anchoring in the pelvic floor require further investigation. An improved anatomical-functional interpretation is needed to generate therapeutic concepts orientated at the physiology of the bladder neck.Therefore, the focus of anatomical investigations should be on the external sphincter which is the main muscle responsible for urethral closure as well as on the connective tissue, smooth muscular and neuronal structures in the pelvis. The smooth muscular structures involved are the internal sphincter, the inner parts of the external sphincter, the urethral longitudinal musculature, and parts of the centrum perinei and of the ventral suspension apparatus which fixes the position of the bladder neck and seems to be vital for continence and initiation of micturition. These new findings imply an integral concept for men as was developed for women. A first step in this regard would be a consistent and updated anatomical nomenclature.The basic structures and organs contributing to continence in men are far less well investigated than in women. This concerns anatomical and functional aspects as well. Especially the cooperation of single components and the dynamic anchoring in the pelvic floor require further investigation. An improved anatomical-functional interpretation is needed to generate therapeutic concepts orientated at the physiology of the bladder neck.Therefore, the focus of anatomical investigations should be on the external sphincter which is the main muscle responsible for urethral closure as well as on the connective tissue, smooth muscular and neuronal structures in the pelvis. The smooth muscular structures involved are the internal sphincter, the inner parts of the external sphincter, the urethral longitudinal musculature, and parts of the centrum perinei and of the ventral suspension apparatus which fixes the position of the bladder neck and seems to be vital for continence and initiation of micturition. These new findings imply an integral concept for men as was developed for women. A first step in this regard would be a consistent and updated anatomical nomenclature.