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PubMed1996

[Repair of the wounded and resected kidney surface by the flap of musculus obliques externus abdominus (experimental study)].

The experimental studies in 15 human cadavers and 15 animals (dogs) have been performed to test the use of the flap musculus obliques externus abdominis in plastic repair of wound and resected kidney surface. The vascular and nervous bundle of the muscle has been detected. It is easy to mobilise the muscle, that has good hemostatic, fixing, and plastic properties. Morphological tests of the flap demonstrated no signs of necrosis. There were no changes in kidney parenchyma either.

Abdominal Muscles↗
PubMed1979

Electron microscopic studies on the lamprey meninges.

Lamprey meninges were revealed to consist of four layers. The I (outermost) layer was made up of densely packed collagen fibrils and microfibrils with fibrocytes interposed between them. It contained a vascular network (epidural vascular plexus). The II layer was a cellular layer, consisting of two parts: the outer, membranous and the inner, spongy part. The membranous part was composed of two sheets of type 1 cells which were held together by desmosomes, gap junctions and tight junctions. Continuous basal laminae were found on both the outer and the inner surface of the membranous part. The spongy part consisted of type 2 cells, collagen fibrils and microfibrils, which were loosely arranged. Type 2 cells were joined together with each other, or with type 1 cells, by gap junctions. These cells lacked a basal lamina covering. The III layer was a peculiar thick layer, being mostly occupied by fine filamentous matrix substance with scattered round cells, fibroblasts and microfibrils. The IV (innermost) layer was a thick fibrous one, consisting of two parts: the outer, vascular and the inner, loose part. The former consisted of a vascular network (perineural vascular plexus) and thick bundles of microfibrils which frequently contained a dense filamentous core. The latter was composed of loosely arranged collagen fibrils. The inner part of the I layer (inside the epidural vascular plexus) was considered to correspond to the true dura, and the II and IV layer to the arachnoid and pia in the meninges of higher animals, respectively. Characteristically the subarachnoid space was absent in lamprey meninges, and instead a peuliar "gelatinous" layer, III layer, was present between the II and IV layer.

Animals↗
PubMed1983

Actin filament stress fibers in vascular endothelial cells in vivo.

Fluorescence microscopy with 7-nitrobenz-2-oxa-3-diazole phallacidin was used to survey vertebrate tissues for actin filament bundles comparable to the stress fibers of cultured cells. Such bundles were found only in vascular endothelial cells. Like the stress fibers of cultured cells, these actin filament bundles were stained in a punctate pattern by fluorescent antibodies to both alpha-actinin and myosin. The stress fibers were oriented parallel to the direction of blood flow and were prominent in endothelial cells from regions exposed to high-velocity flow, such as the left ventricle, aortic valve, and aorta. Actin bundles may help the endothelial cell to withstand hemodynamic stress.

Actins↗
PubMed1988

The ultrastructural organization of the basement membrane of Bowman's capsule in the rat renal corpuscle.

The basement membrane of Bowman's capsule (BCBM) of the rat was studied by means of a modified tissue-preservation technique for transmission electron microscopy, which avoids the usual thorough fixation in OsO4 and applies tannic acid and uranyl acetate for staining (Sakai et al. 1986). At most sites the BCBM is multilayered, consisting of one to seven dense layers separated by electron-lucent layers. The latter, which can be termed laminae rarae, contain fine filaments which connect the dense layers to each other and the innermost dense layer to the basal cell membrane of the parietal epithelium. The laminae densae are basically composed of fine filaments arranged in an anastomosing pattern. Individual filaments ranging from 5 to 15 nm in diameter, combine to form filament bundles up to 100 nm in thickness and 1 to 2 micron in length. Within a dense layer, filaments and filamentous bundles are oriented mainly in the same direction. Often the inner dense layers do not form a continuous sheet, and the filamentous bundles are arranged in anastomosing or spiral patterns to form a ribbon-like structure that we call a "microligament". These microligaments are often embedded in basal furrows of the parietal epithelium and are best developed around the vascular pole. Intracellular actin bundles of the parietal cells are regularly associated with these extracellular ribbon-like structures of the basement membrane. In conclusion, the BCBM has an unusual structure: the laminae densae are characterized by their filamentous nature and are arranged in different patterns, i.e. as a multilayered mat and as microligaments.

Animals↗
PubMed1997

Expression patterns of vascular-specific promoters RolC and Sh in transgenic potatoes and their use in engineering PLRV-resistant plants.

The expression patterns of GUS fusion constructs driven by the Agrobacterium rhizogenes RolC and the maize Sh (Shrunken; sucrose synthase-1) promoters were examined in transgenic potatoes (cv. Atlantic). RolC drove high-level gene expression in phloem tissue, bundle sheath cells and vascular parenchyma, but not in xylem or non-vascular tissues. Sh expression was exclusively confined to phloem tissue. Potato leafroll luteovirus (PLRV) replicates only in phloem tissues, and we show that when RolC is used to drive expression of the PLRV coat protein gene, virus-resistant lines can be obtained. In contrast, no significant resistance was observed when the Sh promoter was used.

Animals↗
PubMed2004

Morphological and functional alterations in glycerol preserved rat aortic allografts.

Glycerol preservation is an effective method for long-term preservation of skin allografts and has a potential use in preserving arterial allografts. We evaluated the effect of glycerol concentration and incubation period on vessel-wall integrity of rat aortic allografts. No significant differences were measured in breaking strength (2.3 +/- 0.3 N) and bursting pressure (223 +/- 32 kPa) between standard glycerolized and control segments (1.7 +/- 0.3 N, 226 +/- 17 kPa). Isometric tension measurements showed complete lack of functional contraction and relaxation capacity in allograft segments prepared according to all preservation protocols. Morphologically, thickness of the vessel-wall media diminished after preservation using low (30/50/75%) or high (70/85/98%) concentrations of glycerol, as compared to control segments (i.e. 81 +/- 2.4 microm, 95 +/- 5.6 microm and 125 +/- 3.5 microm, respectively). Confocal microscopy and Fourier analysis demonstrated that vascular collagen and elastin bundle orientation had remained unaltered. Electron microscopy showed defragmentation of luminal endothelial cells. In conclusion, glycerol preservation of rat aorta resulted in an acellular tissue matrix, which maintained biomechanical integrity and extracellular matrix characteristics. The next step in the investigation will be to test the concept of glycerol preservation of arterial allografts in a vascular transplantation model.

Animals↗
PubMed2001

Analysis of the vascular anatomy of the palm and its clinical relevance in Morbus Dupuytren.

The triangular center of the palm is supposedly hypovascularized. Intraoperative clinical studies have shown numerous vessels and nerves rising through the palmar aponeurosis into the skin in this area. To investigate these findings we have dissected 7 cadaver hands in order to analyze the vascular and neural structure of the palm. On an average we have found 30 bundles in the center of the palm. At least half of them were vascular-nerve bundles, the other bundles consisted either of a nerve, an artery or a vein. By means of histological testing we have also found lymphatic vessels accompanying the blood vessels and the nerves. Our study shows a greater number of vessels rising into the skin than has been previously described in the literature, so that we cannot confirm the triangular hypovascular zone in the center of the palm.

Arteries↗
PubMed1994

[Target-like hemosiderotic hemangioma. Further differential diagnosis of Kaposi sarcoma].

Targetoid haemosiderotic haemangioma (THH) can be differentiated from other angiomatous lesions by the characteristic findings on clinical and histological examination. Clinically the solitary lesion is suggestive of a melanocytic or angiomatous origin, surrounded by a haemorrhagic halo in the acute phase. Histological findings vary depending on the duration of the alteration. The pattern has a superficial and a deep dermal component. In the papillary body lesional capillaries are lined by prominent endothelial cells. The surrounding tissue is oedematous and contains masses of erythrocytes or haemosiderin and a lymphocytic infiltrate. Vessels in the deeper dermis have a lymphatic appearance and surround adnexal structures. Further possible similarities with Kaposi sarcoma are dissecting vascular lumina between collagen bundles and spindle cell areas. However, has no atypical cells, eosinophilic globules or apoptotic endothelial cells. Immunohistochemical investigations, which have now revealed BMA 120 for the first time in THH as well as factor VIII-R antigen and Ulex europaeus I lectin, have not so far made any substantial contribution to the differential diagnosis and histogenesis of THH, because markers distinguishing lymphatic from vascular endothelia are still lacking.

Adult↗
PubMed2005

Modified clipless antegrade nerve preservation in robotic-assisted laparoscopic radical prostatectomy with validated sexual function evaluation.

INTRODUCTION: We present our technique for clipless antegrade neurovascular bundle preservation during robotic laparoscopic radical prostatectomy, along with short-term follow-up of our patients' sexual function. TECHNICAL CONSIDERATIONS: Using the da Vinci three-arm robotic system, we performed robotic laparoscopic radical prostatectomy using a transperitoneal approach in an antegrade fashion. After division of the bladder neck, the posterior plane of the prostate was developed distally toward the apex of the prostate in the midline. This plane was then developed completely, releasing the vascular pedicles and neurovascular bundles in a medial to lateral direction, with occasional use of bipolar cautery and without the use of clips or monopolar cautery. Patients with a minimal follow-up of 3 months who did not require open conversion were included in this study. A total of 56 patients met these inclusion criteria between February 2003 and May 2004, with a mean follow-up of 6 months. Patients were given the validated Rand Medical Outcomes Study 36-Item Health Survey, version 2, with the University of California, Los Angeles, Prostate Cancer Index preoperatively and at 1, 3, 6, and 12 months postoperatively. The overall score for both unilateral and bilateral nerve-sparing groups was 35.0, 39.7, 49.4, and 49.6 at 1, 3, 6, and 12 months postoperatively, respectively. These coincided with a return to baseline potency rate of 47%, 54%, 66%, and 69% at 1, 3, 6, and 12 months, respectively. CONCLUSIONS: Antegrade dissection of the neurovascular bundle, avoiding the use of clips or monopolar cautery during robotic laparoscopic radical prostatectomy, may result in early return of sexual function and overall outcome similar to that after radical retropubic prostatectomy.

Adult↗
PubMed1992

A comparative study on the effects of tumor necrosis factor-alpha (TNF-alpha), human angiogenic factor (h-AF) and basic fibroblast growth factor (bFGF) on the chorioallantoic membrane of the chick embryo.

The chorioallantoic membrane (CAM) assay is a widely used bioassay for testing angiogenic activities. In the present study we compared the gross and micromorphological effects of three angiogenic factors applied in Elvax carriers on the CAM: Tumor necrosis factor-alpha (TNF-alpha), human angiogenic factor (h-AF), and basic fibroblast growth factor (bFGF). Our question was whether the CAM responds to these factors which have very different actions with a stereotype or with a factor specific reaction. By microangiography and light microscopy, all positive reactions appeared as a spoke-wheel vascular pattern with a bundle of small capillary blood vessels in the center. These vessels were predominantly of a distended type in h-AF and TNF experiments, while narrower capillary vessels followed bFGF application. Chorioallantoic ectoderm and endoderm were thickened by cell accumulation and the mesenchymal stroma of the CAM was edematous and infiltrated with leucocytes in all three reactions. Additionally, bFGF experiments showed areas of densely arranged fibroblasts. Observations in vivo showed chorioallantoic tissue movements as a possible mechanism for the spokewheel vascular pattern. As compared with our results from studies of cytokinetics with bromodeoxyuridine, these current findings indicate that chemotaxis is responsible for the chorioallantoic angiogenic reaction rather than cellular proliferation.

Allantois↗
PubMed1997

Cucumber mosaic virus is restricted from entering minor veins in transgenic tobacco exhibiting replicase-mediated resistance.

Transgenic tobacco plants expressing an altered form of the 2a replicase gene from cucumber mosaic virus (CMV) strain Fny exhibited a suppression of viral replication and restricted viral movement when inoculated mechanically or by insect vectors. Resistant plants could be infected, however, through a graft-union with an infected nontransformed plant. The infectious entity moved quickly through intergrafts of resistant tissue, indicating that it could move without replicating in the vascular system. Viral replication continued to be suppressed in systemically infected transgenic portions of grafted plants, as demonstrated by the synthesis of lower levels of viral RNA than in systemically infected nontransformed portions of the same grafted plants. Cell-to-cell spread within this tissue also occurred much more slowly than in nontransformed tobacco. Young inoculated levels of transgenic-resistant plants exhibited limited cell-to-cell virus movement, revealed as chlorotic lesions, but no long-distance virus movement occurred. The results of in situ hybridization studies on these lesions indicated that CMV RNA does not traffic from bundle-sheath cells to vascular parenchyma or companion cells in chlorotic lesions on the inoculated leaves of transgenic-resistant tobacco plants. The inhibition of long-distance movement was a consequence of restricted entry of the infectious entity into the vascular system.

Cucumovirus↗
PubMed1999

Nitric oxide synthase-containing cells in the retina, pigmented epithelium, choroid, and sclera of the chick eye.

Nitric oxide is a nonconventional neurotransmitter that is produced as needed by the enzyme nitric oxide synthase (NOS). NOS has been detected in numerous neural structures, including distinct populations of retinal neurons in a variety of vertebrate species. The purpose of this study was to identify NOS-containing cells in the retina and extraretinal ocular tissues of hatched chicks. NOS was detected in frozen sections by using nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase histochemistry and antisera to neuronal NOS. In the retina, NADPH-diaphorase and NOS immunolabelling were present in four subtypes of amacrine cells, some ganglion cells, efferent fibers, efferent target cells, and neuronal processes in both plexiform layers, whereas diaphorase alone was detected in photoreceptor ellipsoids and Müller cells. In addition, NADPH-diaphorase and immunoreactive NOS were detected in axon bundles and innervation to vascular smooth muscle in the choroid, whereas stromal and endothelial cells in the choroid, scleral chondrocytes, and the retinal pigmented epithelium contained only NADPH-diaphorase. The excitotoxin quisqualate destroyed all but one subtype of NOS-immunoreactive amacrine cell and caused increased NADPH-diaphorase activity in Müller cells. We conclude that nitric oxide is produced by many different cells in the chick eye, including retinal amacrine and ganglion cells, Müller cells, retinal pigmented epithelium, and cells in the choroid, and likely has a broad range of visual and regulatory functions.

Animals↗
PubMed2004

Glossal angiomyoma: imaging findings and endovascular treatment.

BACKGROUND: An angiomyoma is an uncommon, benign tumor characterized by numerous vascular channels intermixed with bundles of smooth muscle cells. Oral manifestations are quite rare. We describe for the first time the CT, MRI, and angiographic imaging features and successful preoperative endovascular embolization of an angiomyoma of the tongue. The pathologic findings before and after embolization are also described. METHODS AND RESULTS: A 25-year-old man was seen with a rapidly enlarging tongue mass. Imaging studies revealed the extent and hypervascular nature of this tumor. The diagnosis of angiomyoma was confirmed by histologic examination. Preoperative embolization proved to be helpful in the surgical management of this lesion. CONCLUSIONS: Angiomyoma should be considered in the differential diagnosis of any well-circumscribed, hypervascular, soft tissue tumor in the mouth. In addition, endovascular embolization may be a useful adjunct that facilitates resection.

Adult↗
PubMed1975

[Clinical, electron-microscopic, and histochemical investigations of conjunctivitis lignosa (author's transl)].

A case is briefly described in which a typical conjunctivitis lignosa appeared after the eye had suffered lime burns. In order to help clarify the morphological connection between mucopolysaccharide production and fiber development in the tumor tissue which occurred after the burn, samples were examined histologically, histochemically and with the use of the electron microscope. The tumor had a cartilage like consistency. Its structure could be devided into three regions. Region A is the pseudo-membrane. It has root like extensions which anchor it to the underlying tissue, and which morphologically appear partially homogeneous and partially fibrous. Blood cells and cell remnants are included in the tissue of the pseudomembrane. The histochemical examination of the pseudomembrane did not present a uniform picture. Along with small amounts of dermatan-sulfate and chondroitin-sulfate B the membrane probably contained a rather large amount of hyaluronic acid. The pseudomembrane borders on a granular tissue (Region B) which is distinguished by the wide metachromatic sheathes of the blood vessels found in it and the particularly large number of active fibroblasts along its edges. The silver impregnation method and the electron-microscopic examination showed that the vascular sheathes consist of bundles of reticular fibers which constitute a three-dimensional network. A similar sort of sheath was observed around the fibroblasts. Chondroitin-sulfate makes up the largest fraction of the mucopoly-saccharides near the fibers and appears particularly concentrated at the intersections of the fibers, although it is also diffusely distributed as well. Dermatan-sulfate (or heparan-sulfate) is found only in the mucopolysaccharide sheath of the fibers themselves. The deep region of the tumor (Region C) consists almost exclusively of blood vessels, their sprouts and the fibroblasts which, with their wide fibrous sheathes, almost fill the spaces between the blood vessels. The reticular fibers and their mucopolysaccharide sheathes have the same structure as that observed in Region B, The fact that the mucopolysaccharides did not appear in plaques but rather as bound primarily to the fibers is grounds for suggesting that a fiber development disorder, probably stemming from the pericytes and fibroblasts rich in ergastoplasm and fibrilles, could play the principle role in conjunctivitis lignosa. The cartilagen like consistency of the tumor could be a result of the arrangement of the fibers and their mucopolysaccharide sheathes. Brief remarks are included concerning the therapeutic consequences of the study.

Adult↗
PubMed2005

Mesenchymal hamartoma of the liver in adulthood: immunohistochemical profiles, clinical and histopathological features in two patients.

Mesenchymal hamartoma is an uncommon cystic mass of the liver which occurs primarily in children. There are a few reports of its occurrence in adulthood. Here, we present two cases in female patients, 54 and 51 years old. Radiological examinations in both patients showed multiple cystic lesions in the liver. Surgically, total cystectomy was performed in the first patient, while an unroofing procedure was done in the second patient (due to misdiagnosis of the lesion as a simple cyst of the liver). On microscopic examinations of the lesion in each patient, a multilocular cyst was observed, lined by flattened epithelium and surrounded by a mesenchymal component composed of mature connective tissue, arterial and venous vascular structures, peripheral nerve bundles, and ductal structures. An immunohistochemical panel consisting of desmin, smooth-muscle actin, S-100, vimentin, CD34, carcinoembryonic antigen, pancytokeratin, cytokeratin 7, cytokeratin 8, cytokeratin 17, cytokeratin 18, cytokeratin 19, and cytokeratin 20 was applied to paraffin sections. Immunoreactivity for cytokeratin 7 and cytokeratin 19 was observed in cystic epithelium and ductal structures. Focal and patchy desmin immunoreactivity was observed in connective tissue. S-100 was positive only in peripheral nerve bundles. In conclusion, mesenchymal hamartoma of the liver in adulthood is a localized tumoral abnormality that precedes birth, and which has delayed clinical presentation. These lesions seems to be related to a maturation process. During this period of maturation, immature edematous stroma rich in mucopolysaccharides may convert to mature paucicellular hyalinized connective tissue. This maturation process may be also related to loss of premalignant potential of these tumors.

Desmin↗
PubMed1993

Structural study of the frog Rana temporaria larval stomach.

The gastric wall of Rana temporaria tadpoles consists of a well-developed mucosa and thin muscular and serosa layers. Three cellular types--mucous, ciliated and endocrine cells--make up the lining epithelium. Different types of endocrine cells exist. Argyrophylic endocrine cells can be recognized in semithin sections of plastic-embedded material while non-argyrophylic endocrine cells can only be identified under the electron microscope. Glands are composed mainly of well-differentiated oxyntic cells and, occasionally, scarce endocrine cells. Oxyntic cells show abundant mitochondria and smooth endoplasmic reticulum, but do not contain zymogen granules as do those present in adults. Secretory canaliculi with microvilli are also well-developed. The lamina propria contains numerous vascular sinuses and nerve bundles which innervate the endothelium and some endocrine cells. The neuroendocrine regulation of frog gastric functions seems therefore to have developed in young tadpoles. Nerve fibers also innervate the muscular propria, which is composed of a single layer of smooth muscle cells. Underlying the muscle, connective fibers and a flattened layer of mesothelial cells make up the serosa. In summary, the structure of the frog larval stomach shows a well-differentiated histological pattern, especially referring to surface epithelium and glands. Some of the histological traits will also be present in adult frogs while others are characteristic of the tadpole's stage.

Animals↗
PubMed2006

Distribution and significance of nerve growth factor receptor (NGFR/p75NTR) in normal, benign and malignant breast tissue.

Nerve growth factor receptor (NGFR) is a transmembrane glycoprotein without intrinsic tyrosine kinase activity, whose expression is not restricted to neural cells. NGFR is reported to act as a tumour suppressor, negatively regulating cell growth and proliferation. NGFR expression was immunohistochemically analysed in normal breast tissue and in 140 benign, biphasic and preinvasive breast lesions, in 22 tumours with myoepithelial differentiation and in two cohorts of breast cancer patients: a series of 245 invasive breast carcinomas studied with tissue microarrays and 37 high-grade invasive ductal carcinomas with basal-like immunophenotype. NGFR consistently displayed membrane reactivity in myoepithelial cells arranged as a continuous layer around normal ducts and lobular units, intralobular fibroblasts, vascular adventitia and nerve bundles. Myoepithelial cells of benign proliferations and pre-invasive lesions were consistently positive for NGFR. Scattered NGFR-positive cells were observed in solid areas of six out of nine cases of hyperplasia of usual type, whereas in flat atypia, lobular carcinoma in situ and virtually all cases of ductal carcinoma in situ (97.5%), NGFR was restricted to the myoepithelial layer. Positivity for NGFR was observed in 11 out of 245 (4.5%) breast carcinomas, nine out of 20 (45%) metaplastic breast carcinomas and 14 out of 37 (38%) basal-like breast carcinomas. NGFR expression in invasive tumours significantly correlated with that of cytokeratins 5/6 (P<0.05), 14 (P<0.0001) and 17 (P<0.0005) and EGFR (P<0.0001) and displayed an inverse correlation with oestrogen and progesterone receptors (both, P<0.0001). NGFR showed a statistically significant association with longer disease-free (P<0.05) and overall survival (P<0.01) in the cohort of patients with basal-like carcinomas. This study demonstrates the usefulness of NGFR as a new adjunct marker to identify myoepithelial cells in preinvasive lesions and myoepithelial differentiation in breast carcinomas. Furthermore, provisional data in a small number of basal-like breast carcinomas suggest that NGFR may identify a subgroup of basal-like breast carcinomas with good prognosis.

Breast↗
PubMed2000

F-actin fiber distribution in glomerular cells: structural and functional implications.

BACKGROUND: Glomerular distention is associated with cellular mechanical strain. In addition, glomerular distention/contraction is assumed to influence the filtration rate through changes in filtration surface area. A contractile cytoskeleton in podocytes and mesangial cells, formed by F-actin-containing stress fibers, maintains structural integrity and modulates glomerular expansion. In this study, the glomerular cell distribution of F-actin and vimentin filaments was studied in normal control and nine-month streptozotocin-diabetic rats. Results in situ were compared with observations in tissue culture. METHODS: Microdissected rat glomeruli were perfused to obtain a physiological 25% glomerular expansion over the basal value. Fixation was done without change in glomerular volume. Dual fluorescent labeling of F-actin and vimentin was carried out, and samples were examined by confocal laser scanning microscopy. RESULTS: The podocyte cell bodies and their cytoplasmic projections, including the foot processes, contained bundles of vimentin-containing fibers. Except for a thin layer at the base of foot processes, they did not demonstrate F-actin. While mesangial cells in culture had F-actin as long stress fibers resembling tense cables, mesangial cells stretched in situ contained a maze of short tortuous F-actin fibers organized in bundles that often encircled vascular spaces. This fibrillar organization was disrupted in diabetic glomeruli. CONCLUSION: Mesangial cells, but not podocytes, contain a cytoskeleton capable of contraction that is disorganized in long-term diabetes. Together with previous observations, the distribution of this cytoskeleton suggests that mesangial cell contraction may be involved in the redistribution of glomerular capillary blood flow, but not substantially in the modulation of glomerular distention. Disorganization of stress fibers may be a cause of hyperfiltration in diabetes.

Actins↗