bluuebunny/crossref_metadata_2025 huggingface dataset:
High Density Culturing of Porcine Hepatocytes Immobilized on Nonwoven Polyurethane-Based Biomatrices
Authors: Pahernik S.A. , Thasler W.E. , Doser M. , Gomez-Lechon M.J. , Castell M.J. , Planck H. , Koebe H.G.
Published: April 2003

Objective: Hepatocytes are increasingly used as functional units in bioartificial liver devices. The objective of the present study was to investigate the feasibility of culturing porcine hepatocytes in high density on a novel polyurethane-based nonwoven three-dimensional matrix. We investigated (1) the optimal cell density within this culture configuration, (2) the maintenance of liver-specific morphology and cell functions over long-term periods and (3) the necessity to apply an additional extracellular matrix component (collagen gel). Methods: Nonwoven polyurethane matrices were manufactured by a specially developed fiber extrusion technology. Pig hepatocytes were cultured at various cell densities of 0.1, 0.25, 0.5, 0.75, 1 and 2 × 106 cells/cm2 on three-dimensional networks of nonwoven polyurethane matrices and cell adhesion as well as functional parameters (DNA of nonattached/attached cells, lactate dehydrogenase release and cytochrome P450 activity) were determined. To assess the performance of cells within this configuration albumin and urea excretion was measured over 8 days. The potentially beneficial effect of an additional extracellular matrix configuration was evaluated by comparing the average albumin synthesis in groups of identical cell numbers. Results: The optimal cell density in this three-dimensional culture configuration was 1 × 106 cells/cm2. The functional capacity of hepatocytes was stable for 8 days at an average level of 53.7 ± 5.6 ng/h/µg DNA and of 1.8 ± 0.14 µg/h/µg DNA for albumin and urea excretion, respectively. The supplementation of an extracellular matrix configuration did not improve functional activity of cells. Average albumin synthesis was 35.6 ng/h/µg DNA (28.7, 42.8) and 32.7 ng/h/µg DNA (23.4, 49.2) for collagen-immobilized and control cultures, respectively. Conclusion: The results of the study indicate that nonwoven polyurethane sheets supply a biocompatible support structure for functionally active high density cultures. Thus, nonwoven polyurethane matrices should be further investigated on with respect to their role in the development, optimization and design of bioartificial liver systems.
Synergistic Effect of Titanium Alloy and Collagen Type I on Cell Adhesion, Proliferation and Differentiation of Osteoblast-Like Cells
Authors: Roehlecke C. , Witt M. , Kasper M. , Schulze E. , Wolf C. , Hofer A. , Funk R.H.W.
Published: April 2003

A number of studies have demonstrated the pivotal role of collagen in modulating cell growth and differentiation. In bone, where the extracellular matrix is composed of approximately 85% type I collagen, cellular interaction with matrix components has been shown to be important in the regulation of the osteoblast phenotype. Preservation or enhancement of normal osteoblast function and appositional bone formation after implant placement represents a strategy that can be useful for the purpose of improving osseointegration. In order to further improve biocompatibility, we combined two known favorable compounds, namely the titanium alloy, Ti6A14V, with type I collagen. We assessed the in vitro behavior of primary osteoblasts grown on both fibrillar collagen-coated and tropocollagen-coated Ti6A14V in comparison with uncoated titanium alloy, using an improved adsorption procedure. As parameters of biocompatibility, a variety of processes, including cell attachment, spreading, cytoskeletal organization, focal contact formation, proliferation and expression of a differentiated phenotype, were investigated. Our results demonstrated for the first time that in comparison to uncoated titanium alloy, collagen-coated alloy enhanced spreading and resulted in a more rapid formation of focal adhesions and their associated stress fibers. Growing on collagen-coated Ti6A14V, osteoblasts had a higher proliferative capacity and the intracellular expression of osteopontin was upregulated compared to uncoated titanium alloy. Type I collagen-coated titanium alloy exhibits favorable effects on the initial adhesion and growth activities of osteoblasts, which is encouraging for its potential use as bone graft material. Moreover, collagen type I may serve as an excellent biocompatible carrier for osteotropic factors such as cell adhesion molecules (e.g. fibronectin) or bone-specific growth factors.
Oogenesis in the Marsupial Stripe-Faced Dunnart, Sminthopsis macroura
Authors: Kress A. , Merry N.E. , Selwood L.
Published: April 2003

The timetable of oogenesis in Sminthopsis macroura is accelerated like in other marsupials showing relatively early maturation of the female. On the day of parturition (day 0) migration of primordial germ cells to the indifferent gonads has been completed. Follicular growth seems not to correspond to the biphasic pattern, in which oocyte and follicle grow synchronously until antral stages when only the follicle increases in size, but shows a continuous growth of the oocyte and the follicle up to the time of ovulation. During primordial and early primary follicle stage a paranuclear complex is present in the oocyte, consisting mainly of smooth tubules of endoplasmic reticulum. Cortical granules appear early in oocytes in secondary follicles. The conspicuous inclusions in the antral follicle are the clusters of electron-lucent vesicles in the oocyte. These inclusions grow from multivesicular bodies (MVB), which are formed from Golgi and endoplasmic reticulum vesicles. Further increase in the size of MVB involves the incorporation of endocytic vesicles and the coalescence of larger vesicles. The polarized nature of the oocyte at ovulation is due in part to the to accumulation of these vesicles in the cytoplasm opposite the eccentrically placed nuclear material.
Morphology of the Laminar Junction in Relation to the Shape of the Hoof Capsule and Distal Phalanx in Adult Horses (Equus caballus)
Authors: Thomason Jeffrey J. , Douglas Janet E. , Sears William
Published: April 2003

The purpose was to investigate whether differences in equine hoof shape, which are inferred to alter foot function, are accompanied by differences in morphology of the laminar junction. Ten fore feet from adult horses were segregated into normal and low-angle groups, depending on the dorsal angle of the hoof wall. Twenty measurements of external hoof shape and four of the enclosed distal phalanx were tested for differences between groups, and for intragroup correlations. Three measurements of laminar morphology (spacing, orientation and degree of bend) were recorded for samples of up to 50 primary epidermal laminae at each of 20 sample sites. Sites were distributed over the foot in 5 circumferential columns and 4 proximodistal rows. Intergroup differences were investigated, as were correlations among sample sites of the laminar variables with the shape measurements. Results show differences in hoof shape between groups (but not bone shape) and laminar morphology. Six shape measurements are significantly different between groups: dorsal angle, medial and lateral angles, lateral sole width, solar circumference, and dorsal length. In the normal group, shape measurements show patterns of correlation among regions of the hoof, and between hoof and bone measurements. In the low-angle group, shape correlations occur largely within one region of the hoof (the heels) and in the bone measurements. Laminar spacing tends to be nonsignificantly greater in the low-angle group, while variances for laminar spacing and orientation are significantly greater in this group. Laminar spacing correlates with bone width and coronary circumference (CC) of the hoof in the normal group, but only with CC in the low-angle group. When taken as a whole, and interpreted in light of a model of foot mechanical function, the results appear to indicate a deterioration in structural coherence of the foot in the low-angle group.
Scapular Insertion of the Rabbit Latissimus Dorsi Muscle: Gross Anatomy and Fibre-Type Composition
Authors: Barron David J. , Etherington Phillip J. , Winlove C. Peter , Pepper John R.
Published: April 2003

This paper defines the characteristics and significance of the scapular insertion of the latissimus dorsi muscle (LDM) of the rabbit. In a study of the New Zealand White species (n = 10) the scapular insertion was found to be a consistent anatomical feature of the LDM that made up 12.3% (±2.3) of the total muscle weight. The fibres arise from the medial aspect of the body of the LDM and run in a caudocranial direction to be inserted into a broad, thin tendon beneath the scapula ridge. This is morphologically different from the scapular component of the human LDM which is a well-recognized but inconsistent feature and consists of no more than a small leash of fibres running around the lower pole of the scapula. The scapular insertion was deeper red in colour than the body of the muscle and fibre-typing demonstrated a mean slow-fibre composition of 49% (±2.6) compared to 16% (±1.7) for the body of the muscle (p < 0.01). Mapping of the fibre types throughout the remainder of the LDM confirmed that the body of the muscle was of fast phenotype but with significantly more slow fibres in the superomedial segment of the muscle than elsewhere. This region of the muscle contributes mainly to the scapular insertion and it is proposed that this part of the muscle takes on a predominantly postural role in stabilising the scapula during movement of the forelimb.
Apoptosis in Cultured Rat Islets of Langerhans and Occurrence of Bcl-2, Bak, Bax, Fas and Fas Ligand
Authors: Hanke J.
Published: April 2003

Isolated Langerhans islets are widely used for diabetic transplantation experiments and investigations of the mechanisms leading to the death or survival of insulin-producing cells in cultured islets. The present study was aimed at investigating programmed cell death and the role of apoptosis-associated peptides in insulin and glucagon cells of islets isolated from untreated rats and held in cultured suspension. Islets were removed from medium on days 0, 7, 14, 21 and 29, embedded in Epon, and semi-thin serial sections were prepared. At designated intervals, histologic sections were treated with the direct fluorescein-labelled TUNEL method and immunostained for pancreatic hormones (glucagon, insulin) and apoptotic peptides [Bak, Bax, Fas, Fas ligand (FasL)], as well as for the anti-apoptotic peptide Bcl-2. All tissue sections were investigated using confocal laser scanning microscopy under identical setting for semiquantitative estimation of staining intensity. The percentage of apoptotic cells was between 1.6 and 2.1% and most apoptotic cells were beta-cells. Corresponding cells often contained Bak and Bax. Fas and FasL were mostly detected in islet cells within the first week after preparing the cultured suspension. The insulin content was low (1.1 ± 0.22 ng per islet) directly after isolation. It then increased progressively up to day 14, after which it began to decrease. Glucagon expression, on the other hand, remained high for the entire duration of the investigation. In conclusion, the islet beta-cells may recover after the isolation procedure, but after 4 weeks in culture, both the insulin content and Bcl-2 staining decrease. Moreover, apoptosis is mediated by different mechanisms after the isolation procedure and after culturing the islets for 1 month. The present data may be important for further studies on isolated, cultivated or transplanted islets.
Liver Regeneration on Chicken Chorioallantoic Membrane
Authors: Katoh Masabumi , Nakada Kazuto , Miyazaki Jun-Ichi
Published: April 2003

To explore how the liver regenerates, liver pieces from 15-day-old chicken embryos were grafted onto the chorioallantoic membrane (CAM) of 9-day-old chicken embryos and cultured for 11 days at the longest. The cultured liver pieces were examined histologically. The liver implants were gradually engulfed into the CAM and underwent necrosis of hepatocytes, except in their peripheral areas, during the first 1–4 days after grafting. Surviving cells in the peripheral areas began to proliferate 4 days after grafting. Thereafter, the cells were assembled into normal liver tissues and represented almost all the areas of the implants 9 days after grafting. Only after penetration of blood vessels from CAM did the liver implants enter a phase of rapid regeneration to form well-organized liver tissues. At the early stage of regeneration, the cells at the peripheral areas did not produce albumin, but reproduced it in the regenerated liver tissues, implying that hepatocytes restored their functions that were temporarily lost in the process of regeneration. Thus, we concluded that the liver pieces from 15-day-old chicken embryos had the ability to form normal liver tissues on CAM and that the blood supply played an important role in liver regeneration.
Degeneration and Regeneration of the Lip Mucosal Epithelium after Cryo Treatment in Mice
Authors: Osawa T. , Feng X.-Y. , Abe T. , Hori H. , Nozaka Y.
Published: April 2003

The process of degeneration and regeneration of the lip mucosal epithelium after cryo treatment was observed by transmission electron microscopy. The epithelial cells were degenerated by the formation of ice crystals and subsequently detached from the basement membrane, forming a blister cavity. The separation occurred between the epithelial cells and the lamina densa, leaving a small amount of cell debris on the lamina densa. The surviving cells at the periphery of the blister cavity, especially the cells in the basal half of the epithelium, provided the regeneration cells. They migrated over the cell debris, attached to the lamina densa and gradually phagocytozed it. Finally, they formed hemidesmosomes with the old lamina densa. The connections between the epithelial cells by desmosomes were so tight that desmosomes were preserved even between dead cells and between dead and living cells. Regenerating cells were moving in a multilayered form, remaining connected to each other by the dosmosomes. They were seen to divide by mitosis and thereby increase the number of the cell layer, whilst maintaining their connections with the neighbouring cells.
Bone Density, Dynamic Joint Loading and Joint Degeneration
Authors: Hurwitz Debra E. , Sumner Dale R. , Block Joel A.
Published: April 2003

Increased joint loading and elevated bone density may be involved in the initiation or progression of osteoarthritis. Here, we provide an introduction to the literature on this topic and describe recent studies from our laboratories on several cohorts of subjects who had or were scheduled to have a total hip replacement for unilateral end-stage osteoarthritis. This population is very useful for studying the development and progression of osteoarthritis because of the known higher incidence of osteoarthritis in the contralateral hip than in a normal population. Separate studies of the asymptomatic contralateral hip in these subjects have shown that radiographic signs of early osteoarthritis are associated with increased bone mineral density and some of the gait adaptations typically found in subjects with end-stage osteoarthritis. We have also shown in separate studies of similar populations that elevated bone mineral density is associated with a subsequent accelerated joint space narrowing rate and that elevated hip joint loads during gait are similarly associated with an accelerated narrowing rate. Major questions yet to be answered are how joint loading and bone density interact in the development and progression of joint degeneration.
Degradative Pathways in Tissues of the Temporomandibular Joint
Authors: Puzas J. Edward , Landeau Jean-Marie , Tallents Ross , Albright Jeffries , Schwarz Edward M. , Landesberg Regina
Published: April 2003

Identification of a small animal model that undergoes pathological temporomandibular joint (TMJ) degeneration would represent a significant research tool. To date however, no such model has been described. We therefore have investigated the pathological and immunohistochemical features of the TMJ of a transgenic mouse that over expresses the human form of TNFα. The TMJ of this animal appears to undergo changes that resemble arthriditics of temporomandibular dysfunction. Furthermore, the disc and articular cells express MMP9 and IL-1. Future work should validate this animal model as one that would have utility for the study of TMJ disorders. Maintenance of connective tissues in joints such as the TMJ is a normal process that allows for the reconstitution of important anatomic features. This maintenance involves both the removal and re-synthesis of structural proteins such as collagens, elastins and proteoglycans. An imbalance in the pathways for degradation and synthesis can lead to the degeneration of joint tissues. We describe the presence of a matrix metalloproteinase, MMP9 (92-kD gelatinase), in TMJ disc and articular cells that likely function in the degradative process. Additionally, we show that this enzyme is under the control of pro-inflammatory cytokines whereby TGFβ and IL-1 stimulate and PGE2 inhibits its activity.
Photopolymerized Biomaterials for Application in the Temporomandibular Joint
Authors: Poshusta Amy K. , Anseth Kristi S.
Published: April 2003

Chronic foreign body reactions have limited the successful application of alloplastic implants for treatment of temporomandibular joint (TMJ) disorders. There is a great clinical need for new materials with enhanced properties for application in the diarthrodial joint. Photopolymerizations may provide many advantages for fabricating new biomaterials for the TMJ and may address some of the notable differences between the TMJ and other articulations. Specifically, the feasibility of trans-tissue (i.e. through the skin) photopolymerizations may yield less-invasive surgical procedures. Also, novel 3-dimensional photoprocessing techniques may be used to fabricate patient-specific alloplastic devices for improved compliance and efficacy. Finally, the mild conditions necessary for photopolymerizations make the reaction ideal for encapsulating cells with the potential to create constructs for tissue engineering, which may be beneficial for disk replacement therapies.
Morphogenesis of the Medial Region of the Developing Mandible Is Regulated by Multiple Signaling Pathways
Authors: Mina Mina
Published: April 2003

Experimental evidence indicates that the mandibular primordia are specified as at least two independent functional regions: two large lateral (proximal) regions where morphogenesis is dependent on FGF-8 signaling, and a small medial region where morphogenesis is independent of FGF-8 and dependent on other signals. The patterns of expression of multiple signaling molecules and regulatory genes in the epithelium and mesenchyme of the medial region suggest that the regulatory hierarchies controlling morphogenesis of the medial region of the developing mandible are complex and involve multiple pathways. Recent genetic studies indicate that the ‘ET-1-dHAND-Msx1 pathway’ constitutes one of the genetic pathways involved in outgrowth and morphogenesis of the medial region. Functional studies in chick mandible suggest that FGFs (other then FGF-8) and BMPs are also part of signaling pathways that regulate morphogenesis of the medial region. These studies suggest that in the medial region of the developing mandible, FGF-mediated signaling is involved in growth-promoting interaction, whereas BMP-mediated signaling is involved in chondrogenesis.
Engineered Cartilage, Bone, Joints, and Menisci
Authors: Glowacki Julie
Published: April 2003

Reconstruction of many musculoskeletal structures can be accomplished by bone grafting and implantation of prostheses. Alternate approaches are needed, however, for repair of complex structures such as articular cartilage surfaces and the temporomandibular meniscus and joint. Tissue engineering, either cell-free or cell-based, offers promise because of recent advances in materials research and in our knowledge of the cellular and molecular mechanisms of tissue repair. There are three considerations in designing a construct for engineered tissue: the source of cells, if any; the nature of the carrier or scaffold; and use, if any, of genes, factors, or adjuvants. Autogenous cells, often expanded in vitro, have been useful for cartilage tissue engineering. Precursor/progenitor cells are advantageous for bone tissue. There are many natural and synthetic resorbable materials with good biocompatibility and tissue compatibility that can be modified to have the porosity and mechanical properties needed for specific applications. The scaffolds can also be modified to provide biological signals to augment repair and integration.
Somatic Cell Exchange Occurs between Mouse Fetal Gonads and Mesonephroi during in vitro Culture
Authors: Nielsen Majken , Byskov Anne Grete
Published: April 2003

Mesonephric cell contribution to the developing mouse gonad has previously been shown to be male-specific in in vitro culture models. This study shows that somatic cell exchange occurs between fetal mouse mesonephroi and gonads during in vitro culture of assembled tissues. Assembling gonads with cell marker-carrying mesonephroi and vice versa identified cell exchange. Two different cell markers were used. One of the markers was the thymidine analogue bromodeoxyuridine (BrdU), which was added to the culture medium during an initial culture period before in vitro culture of assembled tissues in medium without BrdU. The other was bacterial β-galactosidase, which is expressed ubiquitously in tissues from the transgenic mouse strain ROSA26. The tissues were taken from either 10.5- or 11.5-day-old mouse fetuses, and the assembled tissues were cultured for 36–60 h. Both cell markers demonstrated the occurrence of a cell exchange in both directions between the mesonephros and the gonad. The cell contribution was found to be minor and independent of the initial age of the tissue and hours in culture. Further, mesonephric cell contribution was not male-specific. Cell exchange between the two tissues may be due to growth between the assembled tissues rather than active signal-regulated migration. It is suggested that in vitro culture models may not be applicable for investigating mesonephric cell contribution to the developing mouse gonad.
Mammary Epithelial Cell and Adipocyte Co-Culture in a 3-D Matrix: The First Step towards Tissue-Engineered Human Breast Tissue
Authors: Huss Fredrik R.M. , Kratz Gunnar
Published: April 2003

Reconstruction of the female breast after cancer surgery is a demanding task where the methods used today suffer from several disadvantages. In the present study we have investigated the possibility to use tissue engineering methods to regenerate human autologous breast tissue. Human mammary epithelial cells and preadipocytes were derived from breast tissue biopsies from healthy women undergoing reduction mammoplasty, and the two celltypes were co-cultured with conventional cell culture methods as well as in 3-D matrices. The study shows that it is possible to harvest both human mammary epithelial cells and preadipocytes in a single session, propagate several subcultures, and that the cells maintain a normal intercellular distribution and growth-pattern when co-cultured in a 3-D collagen gel. We propose that growth and formation of a tissue closely resembling normal human breast tissue be readily obtained in the described in vitro cell culture set-up using basic tissue engineering principles. This concept may be of great importance in the development of new methods for reconstruction of the human breast.
Muscle Fibre Damage and Regeneration Resulting from Surgical Limb Distraction
Authors: Williams Pamela , Simpson Hamish , Kenwright John , Goldspink Geoffrey
Published: April 2003

Using an animal model of limb distraction, the extent of muscle fibre damage and atrophy resulting from distraction at two different rates (1.3 or 3.0 mm day–1) was investigated. It was found that at the high rate of distraction there was a significantly greater loss of range of joint movement and more muscle fibre atrophy and fibre damage than at the low rate. Muscle fibre damage is usually followed by regeneration. This involves the expression of the neonatal form of myosin heavy chain, which can therefore be used as an indicator of regeneration. It was found that whilst many more fibres showed evidence of damage at the high compared to the low rate, the number of fibres expressing neonatal myosin was significantly reduced, indicating the presence of a population of fibres which was undergoing degeneration without subsequent regeneration. Thus it would appear that beyond a certain rate of distraction, regeneration may be insufficient to replace contractile material damaged by overstretching. It is suggested that these fibres are replaced with connective tissue. This process may contribute to the muscle weakness and loss of range of joint movement which sometimes accompanies limb distraction procedures.
In vivo Measurement of Fascicle Length and Pennation Angle of the Human Biceps femoris Muscle
Authors: Chleboun Gary S. , France Antoinette R. , Crill Matthew T. , Braddock Holly K. , Howell John N.
Published: April 2003

The purpose of this investigation was to measure in vivo fascicle length (Lfas) and pennation angle (PA) of the long head of the biceps femoris muscle (BFlh m.) at different hip and knee angles while the muscle was relaxed using ultrasonography (US). Data were collected from 18 healthy females (23.0 ± 1.8 years). To validate the measurements of the Lfas and PA, the US measurements on cadavers (n = 5), embalmed with the hip and knee in anatomical position, were compared to actual fiber lengths and PA from the dissected muscles. US images from volunteer subjects were recorded when the hip joint was positioned at 0°, 45° and 90° of hip flexion, and at each hip position, the knee joint was placed at 0°, 45° and 90° from full extension. The images were digitized to measure Lfas and PA. Results showed no significant differences between US and direct measurements of the Lfas and PA on the cadaver BFlh m. (p > 0.05). Lfas and PA changed significantly between the different hip and knee positions in volunteer subjects (p < 0.05). Changes in the Lfas and PA are more sensitive to changes in hip position with the knee position constant than to changes in knee position with the hip position constant. This difference may be related to the larger muscle moment arm at the hip resulting in greater excursion of the muscle with changing hip position. Based on the changes in Lfas with changing joint positions, BFlh sarcomere length was estimated to occupy a portion of the ascending limb, the plateau and descending limb of the length-tension relationship over the range of motion studied. US scanning is valid and reliable for measuring Lfas and PA of the BFlh m. An understanding of the dynamic nature of muscle architecture will assist in determining effective and efficient clinical evaluation and rehabilitation techniques.
Ultrastructural Study of Anterograde Transport of Glial Cell Line-Derived Neurotrophic Factor from Dorsal Root Ganglion Neurons of Rats towards the Nerve Terminal
Authors: Ohta Keisuke , Inokuchi Tetsuo , Gen Eizo , Chang Jaekwang
Published: April 2003

The glial cell line-derived neurotrophic factor (GDNF) is a potent neurotrophic substance in the central and peripheral nervous systems. The present immunohistochemical study clarified the ultrastructural localization of GDNF-immunoreactive substance (GDNF-IR) accumulated at transfected sciatic nerve stumps and also at normal spinal dorsal horn, and has demonstrated that GDNF-IR products appear to be located in dense-cored vesicles within the axons. Furthermore, to determine the source of proximally accumulated GDNF in the transected sciatic nerve, we attempted a transection and a double ligation maneuver involving the sciatic nerve. In the early period after the ligation (20 h), GDNF-IR fibers were observed in the proximal and distal segment of the ligations, but no immunoreactivities were detected in the middle segment. On the other hand, at a late period (8 days) after the transection, GDNF-IR fibers had almost disappeared, but weak GDNF-IR was observed in Schwann cells in the proximal and distal stumps of transected nerve. These findings suggest that most of GDNF-IR was transported from the proximal or distal side in the early period, but was locally synthesized by Schwann cells around the ligations in the late period. Spinal rhizotomy caused prominent accumulation of GDNF-IR products at the cut end of the ganglion side of the dorsal root, but not at the ventral root. These results suggested that dorsal root ganglionic (DRG) sensory neurons are one of the origins of GDNF. The fact that small- to medium-sized DRG neurons show enhanced GDNR-IR after the colchicine treatment may support the above suggestion. In conclusion, the present results strongly suggest that a subgroup of DRG sensory neurons synthesized GDNF-containing dense-cored vesicles in the neuronal somata and anterogradely transports the vesicles to peripheral or central axon terminals.
Central Pontine Myelinolysis
Authors: Lampl Christian , Yazdi Kambiz
Published: April 2003

Central pontine myelinolysis (CPM) is a demyelinating disease of the pons often associated with demyelination of other areas of the central nervous system (CNS). The term ‘osmotic demyelinization syndrome’ is used for pontine and extrapontine myelinolysis. In this paper, we are concerned with CPM although the extrapontine one is based on the same pathogenesis. Both share the diagnostic methods, and their prevention and therapy are the same. The etiology and pathogenesis of this disorder are unclear and will be discussed. However, almost all cases of CPM are related to severe diseases. Chronic alcoholism is still the most common underlying condition of CPM patients. In the literature, 174 cases of CPM have been reported in alcoholics since 1986, which is equivalent to an incidence of 39.4%. Likewise, 95 cases of CPM following the correction of hyponatremia have been documented since 1986 (21.5%). The role of hyponatremia and its correction will be outlined in the discussion of the pathogenesis of CPM. The third largest group of CPM cases are liver transplant patients (17.4%), with the development of CPM being attributed to the immunosuppressive agent cyclosporine in particular. Depending on the involvement of other CNS structures, the clinical picture can vary considerably. The large-scale introduction of magnetic resonance imaging has increasingly facilitated the antemortem diagnosis of CPM, although the radiological findings lag behind and do not necessarily correlate with the clinical picture. As yet, there is no specific therapy of choice. A number of therapeutic approaches have been tested and although they have not been compared with regard to their rate of success, they have all led to a substantial improvement in the prognosis of CPM.
Focal Neurological Deficits following Spontaneous Thrombosis of Unruptured Giant Aneurysms
Authors: Schaller Bernhard , Lyrer Philippe
Published: April 2003

Background: Giant aneurysms (GAs) must be regarded as dynamic lesions with respect to their growth and intraluminal thrombus formation, occasionally giving rise to thromboembolic events. Little is known about spontaneous thrombosis of unruptured GAs leading to focal neurological deficits which can mimic arteriosclerotic, epileptic or neoplastic disease. Methods: Three patients (2 men, 27 and 68 years old, and 1 woman, 32 years old) presented with progressive neurological deficits. Neuroradiological studies showed unruptured GAs [two of the middle cerebral artery (MCA), one of the anterior communicating artery] displaying spontaneous near complete intraluminal thrombosis. In one of the cases with a giant MCA aneurysm, acute thrombosis was followed by infarction of the corresponding territory. Results: Partial excision of the intraluminal thrombus was performed in the anterior communicating artery lesion. Wrapping followed by an extracranial-intracranial bypass and stepwise trapping successfully excluded one MCA lesion from circulation. The other MCA aneurysm was treated conservatively. All three patients showed full recovery neurologically after treatment. Conclusion: The reported clinical history of three patients who developed rapid focal progressive neurological deterioration following acute spontaneous thrombosis can be attributed to the acute swelling of the aneurysmal mass. Their pattern of consecutive rapid clinical improvement represents a previously undescribed clinical course of unruptured GAs.
Reaction of Cutaneous Blood Vessels to Successive Insults: Repeated Intradermal Histamine Challenge on Normal and Irritated Human Skin
Authors: Tur E. , Tur Z. , Weltfriend S. , Schulze K. , Maibach H.I.
Published: April 2003

Background: Histamine, a major mediator in endogenous and exogenous skin disorders, has been extensively investigated. Many experiments concern external provocation, yet the sequence of events as well as the influence of timing of the provocating factors require clarification. Objective: To document cutaneous reactivity to histamine rechallenge at different time points, as well as the response of irritated skin (irritant dermatitis) to histamine. Methods: Histamine was intradermally administered on the upper back of 20 volunteers at different time points to 3 sites and following SLS-induced irritant dermatitis to another site. The cutaneous vascular response was measured by laser Doppler flowmetry. Results: The response to a second prick when the first prick response had decayed to half its peak was significantly higher than all the other responses that resulted from a second prick (p < 0.01). The other responses did not significantly differ from each other or from the first prick response. When the histamine prick was performed over a 24-hour SLS patch, the response was greater than at all other sites (p < 0.01). Conclusion: An excitation state, at which the skin readily reacted to the second insult, may underlie the augmentation of the response to a histamine prick over the irritated skin. Irritation modulates cytokines, which may be the mechanism by which the response to histamine administration is enhanced. Tachyphylaxis did not occur at the time points tested, but may occur at longer intervals, necessitating further investigation.
Prenatal and Perinatal Aspects of a Giant Fetal Cervicothoracal Lymphangioma
Authors: Axt-Fliedner R. , Hendrik H.J. , Schwaiger C. , Ertan A.K. , Friedrich M. , Schmidt W.
Published: April 2003

A massive cervicothoracal lymphangioma was diagnosed in a fetus at 25 weeks of gestation. On ultrasound study, the mass showed septated, cystic components and extended from the right submandibular region to the right anterolateral thoracic wall including the right axilla and right scapula. Close sonographic follow-up revealed an increase in the size of the lymphangioma without fetal hydrops. An interdisciplinary approach including a pediatric surgeon, neonatologist, perinatologist and anesthesiologist was chosen. Elective cesarean section under general anesthesia was planned at 37 + 0 weeks of gestation. Surgical correction of the lymphangioma was successfully performed on the 4th day of life. Possible differential diagnoses and the obstetrical management are presented.
Gelatin Sponge Embolization
Authors: O’Brien John M. , Milligan Douglas A. , Barton John R.
Published: April 2003

Despite the morbidity and mortality associated with early midtrimester premature rupture of the membranes (PROM), limited therapeutic options currently exist for its treatment. A new operative approach to this condition termed embolization involves intra-uterine administration of a gelatin sponge which can remarkably reduce or eliminate further loss of amniotic fluid. A successful case of embolization for the treatment of iatrogenic previable PROM complicating therapeutic fetoscopy is described.
Erythropoietin as Treatment for Late Hyporegenerative Anemia in Neonates with Rh Hemolytic Disease after in utero Exchange Transfusion
Authors: Nicaise Claire , Gire Catherine , Casha Paul , d’Ercole Claude , Chau Cécile , Palix Christian
Published: April 2003

We report the effects of recombinant human erythropoietin (rHuEPO) in the treatment of late hyporegenerative anemia in 2 neonates with Rh hemolytic disease who had received several in utero exchange transfusions. In both cases anemia occurred at 6 weeks of age and we started therapy at approximately 70 days of age. We used rHuEPO at 250 U/kg three times a week. We also used high-dose intravenous immunoglobulin therapy. One week after initiation of erythropoietin treatment, an increase in reticulocyte count and Hb level was noted in our 2 patients. They did not require further erythrocyte transfusions but they already had received two transfusions after birth. There were no side effects attributable to rHuEPO treatment.
Expression of C-Type Natriuretic Peptide in Human Placenta and Myometrium in Normal Pregnancies and Pregnancies Complicated by Intrauterine Growth Retardation
Authors: Stepan Holger , Faber Renaldo , Stegemann Stephanie , Schultheiss Heinz-Peter , Walther Thomas
Published: April 2003

Objective: C-type natriuretic peptide (CNP) is a vasoactive hormone and the endothelial component of the natriuretic peptide system. At present, nothing is known about CNP expression in human reproductive tissue. Since CNP shows antimitogenic and vasodilatative properties, it was the aim of the study to investigate whether CNP expression is altered in placenta and myometrium from pregnancies complicated by intrauterine growth retardation. Methods: CNP expression was examined by RNase protection assay in human placenta and myometrium from six normal term pregnancies, six pregnancies with preterm delivery and six pregnancies complicated by intrauterine growth retardation (IUGR). Results: In placenta and myometrium, CNP expression levels did not differ between term and preterm pregnancies (40 vs. 28 weeks of gestation). In pregnancies with IUGR (34 weeks of gestation) placental CNP expression was significantly decreased (100.00 ± 18.6 vs. 67.09 ± 8.7; p < 0.05). In the myometrium from IUGR pregnancies CNP expression was significantly increased to 191.48 ± 42.5 (vs. 100.00 ± 15.4; p < 0.05). Conclusions: CNP is expressed in human placenta and myometrium with no dependency on gestational age in the third trimester. Pregnancies with IUGR show an opposite regulation of CNP in placenta and myometrium, which indicates an organ-specific function of the peptide in human reproductive tissue.
Uterine Artery Doppler Velocimetry in Patients with Idiopathic Hydramnios
Authors: Hershkovitz R. , Sheiner E. , Furman B. , Smolin A. , Hallak M. , Mazor M.
Published: April 2003

Objective: To evaluate the role of overdistended uterus on the uterine artery (UA) blood flow velocimetry by comparing UA Doppler in patients with idiopathic hydramnios to patients with normal amniotic fluid (AF) volume. Methods: Pulsatility index (PI) of both UAs was determined prospectively between 26 and 41 weeks of gestation in 72 consecutive pregnant women with singleton pregnancies and idiopathic hydramnios and in 72 pregnant women with normal AF volume. Hydramnios was defined as an AF index (AFI) above 24 cm. A normal amount of AF was defined as an AFI of 6–24 cm. Patients with known fetal structural or chromosomal anomalies and those with diabetes mellitus were excluded. Results: No significant differences were observed between the groups with regard to maternal age, gravidity, and gestational age at examination. Gestational age at delivery and accordingly birth weight were significantly lower in patients with hydramnios compared to those with a normal AFI (34.9 ± 2.1 vs. 39.1 ± 1.2, p < 0.001; 2,508 ± 399 vs. 2,995 ± 420, p < 0.001, respectively). No significant differences were noted between right UA PI (0.73 ± 0.3 in the hydramnios group vs. 0.71 ± 0.2 in the control group; p = 0.091) and left UA PI (0.91 ± 0.3 in the hydramnios group vs. 0.84 ± 0.3 in the control group; p = 0.131) of both groups. Conclusion: UA velocimetry in patients with idiopathic hydramnios was not significantly different from those with a normal AF volume.
First-Trimester Ductus venosus Velocimetry in Relation to Nuchal Translucency Thickness and Fetal Karyotype
Authors: Zoppi Maria A. , Putzolu Monica , Ibba Rosa M. , Floris Marcella , Monni Giovanni
Published: April 2003

Aim: To evaluate first-trimester ductus venosus flow in relation to nuchal translucency (NT) and fetal karyotype. Methods: Ductus venosus flow was measured in fetuses with NT greater than or equal to the 95th centile (group A) and in fetuses with NT less than the 95th centile (group B). The waveforms were classified as normal if the lowest forward velocity during atrial contraction (ACV) was positive and abnormal if it was absent or negative. The results were compared with the fetal karyotype. Results: Ductus venosus measurement was carried out in 330 fetuses. In group A, there were 156 fetuses: in 4 cases, it was not possible to obtain the measurement, and in the other 152 cases, 93 (61%) had a normal ACV and 59 (39%) an abnormal ACV. NT thickness was significantly greater in fetuses with abnormal ACV. In 34 out of 156 cases (22%), chromosomal abnormalities were found. Twenty-three chromosomopathies out of 33 (70%) had an abnormal ACV, and 10 (30%) had a normal ACV. A significant association between abnormal karyotype and abnormal ACV was found. Ductus venosus measurement was carried out in 174 fetuses of group B. In 1 case, it was not possible to obtain the measurement. One hundred and seventy-one (99%) cases had a normal ACV, and in 2 (1%) cases the ACV was abnormal. No chromosomal abnormalities were found in group B. Considering group A and group B, a significant association between the finding of an enlarged NT and abnormal ACV was detected (p < 0.05). Conclusions: An abnormal ACV is more frequent in fetuses presenting enlarged NT than in those having normal NTs and in fetuses having the larger nuchal thickness. The probability of having a chromosomal abnormality in fetuses with enlarged NT is greater when an abnormal ACV is found.
MR Autopsy in Fetuses
Authors: Huisman Thierry A.G.M. , Wisser Josef , Stallmach Thomas , Krestin Gabriel P. , Huch Renate , Kubik-Huch Rahel A.
Published: April 2003

Objective: The purpose of this study was to determine whether postmortem magnetic resonance imaging (MR autopsy) could serve as an alternative to necropsy of fetuses. The value of MR autopsy in the validation of the obstetric management and in risk counseling concerning future pregnancies is discussed. Methods: 10 consecutive, malformed fetuses were examined by postmortem MRI within 24 h of delivery. Prenatal ultrasound (US) was performed in all fetuses. Complete necropsy served as gold standard. Results: MR autopsy confirmed every US diagnosis responsible for termination. All MRI findings were confirmed by necropsy. In two fetuses, necropsy gave additional information relevant for risk counseling. Histologic examination corrected the diagnosis in one case. Conclusions: MR autopsy provides valuable information previously only available from necropsy. In parents who refuse perinatal necropsy, the information obtained by MR autopsy can be used to validate obstetric management and to evaluate the risk for future pregnancies. Necropsy however remains the gold standard.
Effects of Urinary Trypsin Inhibitor in Patients at Risk for Premature Labor with a Bulging Fetal Membrane
Authors: Matsuda Yoshio , Yunohara Naoki
Published: April 2003

Objective: To investigate the effect of urinary trypsin inhibitor (UTI) in patients at risk for premature labor with bulging membrane. Methods: Patients who had developed a bulging membrane from 22 to 27 weeks and 6 days of gestation were studied. These cases were divided into two types based on the severity: those with a moderately developed bulging membrane like a ‘dome’ (dome type), and those with a membrane prolapsed into the vagina, resulting in an ‘hourglass’ shape (hourglass type). We compared the outcomes of treatment with or without UTI (UTI group versus non-UTI group) in each type. Gestational age at delivery, birth weight, prolongation time from admission to delivery, and neonatal mortality rate were examined in each group. Results: A total of 43 patients with a bulging membrane were analyzed. In 21 patients with the dome type, gestational age at delivery (the UTI group versus the non-UTI group; 30.4 ± 5.0 versus 26.4 ± 1.9 weeks, p < 0.05), birth weight (1,436.8 ± 708.3 versus 882.8 ± 261.6 g, p < 0.05) and neonatal mortality rate (0/13 versus 3/8, p < 0.05) were all significantly improved by the use of UTI. On the other hand, in 22 patients with the hourglass type, there was no significant difference between the UTI group and the non-UTI group. The overall prevalence of histological chorioamnionitis was 60%. Conclusion: These results suggest that UTI therapy is very effective in patients at risk for premature labor with a moderately developed bulging membrane during the second trimester.
Relationship between Meconium Staining and Amniotic Fluid Volume in Term Pregnancies
Authors: Blackwell Sean C. , Wolfe Honor M. , Redman Mark E. , Hassan Sonia S. , Berry Stanley M. , Treadwell Marjorie C. , Zador Ivan , Carreno Carlos A. , Sorokin Yoram
Published: April 2003

Objective: Our purpose was to evaluate the relationship between meconium-stained amniotic fluid (MEC-AF) and amniotic fluid volume (AFV) and their impact on the risk of cesarean delivery for fetal indications in term pregnancies. Methods: 1,655 live-born singleton gestations delivering at ≧37 weeks within 7 days of sonographic assessment of the amniotic fluid index (AFI) were studied. AFI was categorized as: oligohydramnios (≤5.0 cm); decreased (5.1–8.0 cm); normal (8.1–18.0 cm); increased (18.1–23.9 cm), and polyhydramnios (≧24.0 cm). Frequencies of MEC-AF for each AFV category were stratified by gestational age (GA) and rates of cesarean delivery for fetal indications compared between patients with clear amniotic fluid and those with MEC-AF. Stepwise logistic regression analyses were performed for determinants of MEC-AF and the need for cesarean delivery for fetal indications. Results: The frequency of MEC-AF at birth in term pregnancies was not related to AFV: oligohydramnios (16.7%); decreased (16.7%); normal (20.1%); increased (24.4%), and polyhydramnios (22.1%). The only factor associated with the occurrence of MEC-AF was increasing GA at delivery (p < 0.01). Both MEC-AF (p < 0.02) and decreasing neonatal ponderal index (p < 0.02) were independently associated with cesarean delivery for fetal distress. Conclusions: MEC-AF does not appear to be related to AFV in term pregnancies, and its presence increases the risk of cesarean delivery for fetal distress independent of AFV and neonatal ponderal index.
Prenatal Diagnosis of L1 Cell Adhesion Molecule Mutations
Authors: Moya Graciela E. , Michaelis Ron C. , Holloway Lynda W. , Sanchez Jose Maria
Published: April 2003

Objective: Discuss the capability for and limitations of prenatal detection of L1 cell adhesion molecule (L1CAM) mutations. Methods: Haplotype analysis by PCR and PAGE. Mutation detection by SSCP, followed by dideoxy sequencing. Confirmation of sequencing results with PCR and NcoI digestion. Results: A 1-bp deletion was found in exon 2 of L1CAM in all affected males and obligate carriers in the pedigree. Prenatal detection is now possible for subsequent pregnancies. Conclusion: In a large gene with widespread mutations such as L1CAM, a mutation must be detected in another family member before direct prenatal mutation testing can be done within the required timeframe. If the proper family members are available, haplotyping offers a fast but indirect test with several limitations.