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PubMed1994

Sulfated proteoglycans in the lamina cribrosa of normal monkey eyes and monkey eyes with laser-induced glaucoma.

The distribution of the sulfated proteoglycans in the lamina cribrosa of normal monkey eyes and monkey eyes with laser-induced glaucoma were analysed by electron microscopy after cuprolinic blue dye binding. Three types of cuprolinic blue-positive filaments, CB-1, CB-2 and CB-3, were identified in the laminar beams of normal monkey eyes. CB-1 and CB-2 were both small filaments representing chondroitin and dermatan sulfate proteoglycan copolymers. The former lined up perpendicularly to the long axis of collagen fibrils, whereas the latter ran axially parallel to collagen fibrils. The large CB-3 filaments, representing chondrotin sulfate proteoglycans, were located around collagen bundles or in loose spaces within the beams. In addition, small CB-4 filaments or punctate structures representing heparan sulfate proteoglycans were found aligned on the basal laminae of blood vessels and glial cells. In the glaucomatous eyes, accumulation and enlargement of collagen-associated proteoglycan filaments were seen, accompanied by the destruction of collagenous beams. Accumulation of chondroitin sulfate proteoglycans was most evident. Prominent filamentous heparan sulfate/heparin proteoglycans were also noted in thickened astrocytic and vascular basal laminae. These may be alterations secondary to the destruction of collagen bundles. They may also represent cellular responses related to intraocular pressure elevation.

Animals↗
PubMed1990

Galanin immunoreactive neurons in the human hypothalamus: colocalization with vasopressin-containing neurons.

Galanin (GA) is a recently described neuropeptide that has been demonstrated to be widely distributed in the hypothalamus of experimental animals. So far there is no immunohistochemical description of GA in the human hypothalamus and, in particular, no studies of the colocalization of this neuropeptide with other transmitter candidates in the human hypothalamus. We have now investigated this question immunohistochemically by using human brains fixed by vascular perfusion within 24 hours of death. Nerve cell bodies and fibers stained for GA were observed throughout the hypothalamus. Major populations of GA-ir cell bodies were found in the suprachiasmatic, intermediate, supraoptic, paraventricular, arcuate, tuberomammillary, and supramammillary nuclei. Scattered positive neurons were found in the periventricular preoptic area, the posterior hypothalamic nucleus, the lateral hypothalamic area, and zona incerta. A few positive cells were located in the dorsomedial and ventromedial hypothalamic nuclei. The number of GA-ir neurons estimated from three brains was 11,100 +/- 2,400 for the intermediate nucleus, 57,800 +/- 9,100 for the supraoptic nucleus and 47,400 +/- 13,900 for the paraventricular nucleus. GA-ir fibers were widely distributed in the hypothalamus. They were more dense in the periventricular and medial hypothalamic zones, whereas the lateral tuberal nuclei and the dorsolateral part of the supraoptic nucleus contained sparse positive fibers. The mammillary complex contained almost no GA-ir fibers. In the ventromedial tuberal region, GA-ir axons formed bundles travelling down in the infundibular stem. In the median eminence the vascular plexus was wrapped by GA-ir fiber networks. The coexistence of GA with arginine vasopressin (AVP), oxytocin (OXY), and tyrosine hydroxylase (TH) was examined in the supraoptic, paraventricular, and suprachiasmatic nuclei in adjacent paraffin sections. Neurons containing both GA and AVP were very common in the supraoptic nucleus and also occurred in the paraventricular and suprachiasmatic nuclei. The supraoptic and paraventricular nuclei also contained some neurons immunoreactive for both GA and OXY. Neurons positive for GA and TH were rare. The topographic distribution of GA-ir neuronal structures in the hypothalamus and the colocalization of GA, principally with AVP and to a lesser extent with OXY, in some hypothalamic nuclei constitute anatomical evidence that this neuropeptide may be involved in the regulation of endocrine, autonomic, and behavioural homeostatic responses.

Aged↗
PubMed1989

Alpha-smooth muscle actin, a differentiation marker of smooth muscle cells, is present in microfilamentous bundles of pericytes.

alpha-Smooth muscle (alpha-sm) actin, an isoform typical of smooth muscle cells (SMC) and present in high amounts in vascular SMC, was demonstrated in the cytoplasm of pericytes of various rat and human organs by means of immunocytochemistry at the electron microscopic level. In SMC and pericytes, alpha-sm actin was localized in microfilament bundles, strengthening the assumption that it is the functional isoform in these cell types and supporting the assumption that pericytes exert contractile functions.

Actin Cytoskeleton↗
PubMed1992

[Doppler echocardiographic assessment of left atrial and left ventricular function during right bundle branch block].

Electrocardiographic, echocardiographic and Doppler echocardiographic studies were performed in 44 patients with coronary heart disease and complete right bundle branch block. The patients were found to have an impaired phase pattern of left ventricular systole and diastole as more prolonged length of its isometric relaxation and contraction, lower economic feasibility and efficiency of its contraction, moderate dilation and hypertrophy. Hemodynamic abnormalities in the left heart in these patients are closely correlate with the changes in the phase pattern of right ventricular systole and they turn out to be so greater as the degree of its hypertrophy is. In complete right bundle branch block, left ventricular pump dysfunction leads to decreased cardiac output and cardiac index, increased total peripheral vascular resistance, thus predisposing to impaired greater circulation.

Adult↗
PubMed1995

Limb salvage surgery with microsurgical reconstruction for the treatment of musculoskeletal tumours involving the upper extremity.

Microsurgical reconstructive techniques have been applied in the management of 14 patients with malignant bone and soft tissue tumours as well as for 30 patients with benign but aggressive bone lesions affecting the upper extremity. Vascularised bone grafts were used in 6 patients with malignant bone tumours and 30 patients with aggressive bone lesions. Reconstruction with soft tissue free flap transfer was required in 6 patients with soft tissue defects, primarily following excision of soft tissue tumours in 2 and after excision of recurrent tumours in 4 patients. Microneural dissection and vascular reconstruction were performed in 2 patients with tumours around the major neurovascular bundles. The patients were followed up for varying periods, ranging from 1 to 12 years and assessment of the limb function was performed using Enneking's system of evaluation. There were no local recurrences. In the malignant tumour group, 3 patients died of systemic disease, 7 were alive but with disease and 4 were disease free. Extremity function was excellent in 3 patients, good in 6 patients, fair in 4 patients and poor in 1 patient. In the benign bone tumour group, extremity function was graded as excellent in 12 patients, good in 14 patients, fair in 3 patients and poor in 1 patient. The vascular bone grafts united in all but 3 patients at 4 months following surgery. Minimal donor site complications had been recorded and there had been no failures. Useful limb salvage may thus be achieved with the application of microsurgical techniques for a variety of indications in limb salvage surgery after tumour excision.

Adolescent↗
PubMed1996

Morphological variability of smooth muscle cells in human nasal swell bodies.

The complex functional behavior of nasal swell bodies is still not completely understood. In the present study the histology of the vessels involved in the swelling mechanism is examined and the ultrastructural appearances described of the different types of smooth muscle cells located in the vascular wall of swell bodies in the human inferior turbinate. Even though the majority of smooth muscle cells of the nasal swell bodies showed a normal, elongated appearance comparable to other smooth muscle cells elsewhere in the body, a variety of cells with atypical shapes could be detected that have not been described previously in vessels of the nasal mucosa. The diameters of the smooth muscle cells in general were strikingly variable. The individual smooth muscle cells were surrounded by a basal lamina that was occasionally disrupted or doubled. Myoblasts were separated by a connective tissue space containing collagen fibrils, mature elastin fibers and bundles of microfibrils. The latter two types of fibers and fibrils occurred mainly in the outer parts of the muscular coat. The endowment of cytoplasmic components was similar in all smooth muscle cells of the vascular wall in the swell bodies. These findings indicate that the specific feature of smooth musculature presumably resides in the unusual morphological variability of the single cells present, as well as in the striking heterogeneity of the arrangement of bundles of these cells in the vascular wall.

Connective Tissue↗
PubMed2002

[Clinical and structural parallels in changes of the myocardial conduction system in diphtheria patients].

AIM: Comparison of the results of clinical device investigations of the heart with morphological autopsy evidence in diphtheria. MATERIAL AND METHODS: Hearts of 309 patients with diphtheria aged 25 to 80 years and 60 hearts of patients who died of diphtheria were investigated using ECG, echo-CG, doppler echo-CG, Holter ECG monitoring, biochemical tests of blood. Structural study of cardiac conduction included examination of the sinus-atrial node, atrioventricular node and bundle regarding the adjacent myocardium. RESULTS: Variants of structural-functional state of the myocardium and conduction system are explained by variability of the pathological processes which arose due to individual features of the conduction system structure and location, relationships with the myocardium. In acute diphtheria (day 1-10) dystrophic, necrobiotic and vascular disorders prevailed followed on days 11-30 by inflammation ending in myocardiosclerosis. Nodes and bundles of the conduction system are affected less frequently than the myocardium. CONCLUSION: A correlation exists between structural state of the cardiac conduction system and variants of clinical affection of the heart in diphtheria.

Adult↗
PubMed1989

Hemodynamic and electrophysiologic effects of amlodipine, a new calcium channel blocker.

The effects of amlodipine (300 micrograms/kg administered intravenously), a new, long-acting, dihydropyridine class, calcium channel blocking drug, were studied in atrially paced (120 beats/min), autonomically blocked dogs. Hemodynamic and electrophysiologic parameters were measured before and up to 3 hours after amlodipine. Coronary blood flow was significantly increased 10 and 30 minutes after drug administration, whereas cardiac output and mean arterial pressure were unaffected. Coronary vascular resistance was decreased but total systemic vascular resistance did not change. Atrioventricular (AV) nodal conduction was slightly prolonged, as reflected by increases in atrial-His bundle and AV conduction times and PR interval, 30 minutes after administration. All parameters returned toward their control values within 3 hours after drug administration. Comparison of coronary vascular resistance and AV conduction changes with those previously reported for other calcium channel blocking drugs where autonomic blockade existed suggests that at equivalent levels of coronary vasodilation, amlodipine's effects more closely resemble the effects of diltiazem or verapamil than other dihydropyridines.

Amlodipine↗
PubMed1999

De novo induction of island capsule flap by using two silastic sheets: Part 1. Generation.

A new experimental model for de novo generation of an axial pattern island flap has been designed in a rat model. The purpose of this study was to make a sufficient vascular carrier, as an island capsule flap, with only vascular pedicles and addition of collagen fibers induced by foreign-body reaction. The femoral arteriovenous bundle was isolated and sandwiched between two 2.5 x 1.5 cm Silastic sheets. Eight weeks later, as a delay procedure, femoral vessels were ligated at the distal end of the Silastic sheets and the four margins of the sheets were divided except for the vascular pedicle. This capsule flap was raised as a secondary island flap connected only by its vascular pedicle, then it was sutured back in place. Ten days after the delay procedure, the upper Silastic sheet was removed and a full-thickness skin graft was performed on the capsular island flap. Animals were killed at 80 days. A total of 40 axial pattern capsulocutaneous flaps from 20 Sprague-Dawley rats were successfully achieved. Pathologic study revealed neovascularization, and abundantly impregnated vascular structures near the pedicle were observed with randomly developed collagen fibers. The skin graft took 100 percent on this newly formed capsular flap; therefore, the capsule structure was able to survive on its own and support skin grafts. This experiment, by using an isolated femoral artery and vein as the main pedicle, led to the formation of a capsule flap through a normal foreign body reaction between two Silastic sheet implants. This new flap can be used as a reliable vascular carrier for various needs with minimal donor morbidity.

Animals↗
PubMed1993

Intermediate filaments and ATPase activity in the vascular wall of vertebrates.

The vascular wall of aorta and vena cava was examined for adenosine triphosphatase (ATPase) activity and cytoskeletal intermediate filaments (IF) in different representatives of vertebrates. Enzyme activity was studied by the modified method of Padykula and Herman. A streptavididin-biotin immunohistochemical method was applied to reveal desmin (D) and vimentin (V) IF. Endothelial cells of all vessels were V-positive and D-negative and exhibit high ATPase activity. Vascular smooth muscle cells (SMC) in lower vertebrates (pisces and amphibia) were also V-positive and D-negative, but showed low ATPase activity. SMC were D-positive and V-negative and possessed high enzyme activity in aves and mammals, similar to that of the endothelium. In cow vascular wall D-reactivity and high ATPase activity were mostly expressed in bundles of mosaically arranged thick SMC fibres of the outer aortic media as well as in the longitudinal fibres in the inferior vena cava. In higher vertebrates SMC of vasa vasorum were both V- and D-positive and showed high enzyme activity. The results demonstrate that D-immunoreactivity is mostly expressed in SMC of layers of high functional activity, which correlates with the intense ATPase reaction in these cells.

Adenosine Triphosphatases↗
PubMed1988

Laminin and type IV collagen in different histological stages of Kaposi's sarcoma and other vascular lesions of blood vessel or lymphatic vessel origin.

Immunohistochemical staining was used to demonstrate basement membrane (BM) laminin and type IV collagen in eight cases of Kaposi's sarcoma (KS). These KS were not associated with AIDS and represented different histological stages of the disease: patch (three cases), plaque (one case), and nodule (four cases). Nine cases of benign angiogenic lesions, five of blood vessel origin, and four of lymphatic vessel origin were also studied. An early event in vascular proliferation at the patch stage of KS was an intersection of dermal collagen bundles and the appearance of granular BM material around this space. With the increase of amount and linear arrangement of BM material, well-defined capillaries were formed. Two types of capillary were found in KS lesions. One showed morphological features of blood capillaries, with a round lumen; thick, continuous BM, and occasional pericytes in the wall. The other included irregularly shaped vessels with thin, often disrupted BMs; thus these capillaries morphologically resembled lymphatic capillaries. BM staining also clearly revealed the vascular nature of the nodular lesions of KS, which were composed of a network of slit-like spaces surrounded by BMs. The solid tumor cell areas were sparse; they were composed of spindle-shaped cells surrounded by thin, interrupted basal laminae. By using antibodies against human laminin and human type IV collagen, it was also possible to demonstrate thin, widely disrupted BMs subendothelially in normal dermal lymphatic capillaries. Typically, the BMs in lymphangiomas and lymphangiectasias were continuous and more clearly defined.

Aged↗
PubMed1997

Distribution pattern of tenascin-C in normal and neoplastic mesenchymal tissues.

Descriptions for tenascin-C distribution are largely restricted to epithelial tumours. The present study utilized newly developed and characterized monoclonal (hT191) and polyclonal antibodies to investigate the distribution pattern of tenascin-C in a panel of mesenchymal tumours, which was contrasted with normal tissue. The specific antibodies recognized the distinctive star-like hexabrachion protein isolated from transformed cell-culture medium and serum from normal individuals. In normal tissues, a strong tenascin-C expression in the extracellular matrix was largely restricted to basement-membrane regions of epithelium and tonsilar sinusoids, pericellularly within smooth-muscle bundles, associated with perimysial, -chondrial, -neurial and -tendon surfaces, and diffusely within vascular adventitia. It was found in the corresponding tumours of the neural sheath (schwannoma) and smooth muscle (leiomyosarcoma), and was abundantly present around certain blood vessels of mesenchymal tumours. Although not detected in normal muscle, or in adipose or fibrous connective tissue, neo-expression of tenascin-C was shown in more than half of the rhabdomyosarcomas, fibromas and liposarcomas, with an increased positive percentage in variably malignant myxoid liposarcomas compared with lipoma-like sarcomas. Tenascin-C was typically found in the extracellular matrix of soft-tissue tumours, but was notably absent from the epithelial-cell components of mixed epithelial/mesenchymal tumours. Its apparently enhanced expression in soft-tissue tumours differs from that of most other large extracellular-matrix proteins, suggesting possible functional involvement of the cell-adhesion molecule, tenascin-C, in the neoplastic phenotype.

Antibodies↗
PubMed1998

Functional anatomy of the human efferent tear ducts: a new theory of tear outflow mechanism.

BACKGROUND: The mechanism of lacrimal drainage under physiological conditions is controversial. The aim of this study was to analyze the three-dimensional architecture of human efferent tear ducts from functional and clinical points of view. A new theory of tear outflow is discussed. METHODS: Thirty-two prepared lacrimal systems of adults were examined by histological, immunohistochemical and scanning electron microscopic techniques. RESULTS: The wall of the lacrimal sac is made up of collagen bundles, elastic and reticular fibers arranged in a helical pattern. Wide luminal vascular plexus are embedded in this helical system and connected to the cavernous tissue of the inferior turbinate in the region of Hasner's valve. Immunohistochemical analysis showed evidence of type I and type III collagen as well as chondroitin 4- and 6-sulfate. CONCLUSION: With blinking, the lacrimal part of the orbicularis muscle contracts. The fornix of the sac moves in a cranial-lateral direction. Thus the lacrimal sac distends and may be "wrung out" due to its medial attachment and helically arranged fibrillar structures. The vascular plexus may play an important role in the absorption and drainage of lacrimal fluid.

Aged↗
PubMed1991

Utility of arteriography in penetrating extremity injuries.

The role of contrast arteriography in the management of patients with penetrating injuries of the extremities is a subject of active debate. To examine our experience, the charts of patients with penetrating injuries of the extremities were retrospectively reviewed. Data from 82 consecutive patients with 98 wounds over the 5-year period from January 1984 to December 1988 were reviewed. Sixty-five arteriograms were obtained to investigate 98 wounds: 8 to localize a clinically apparent wound and 57 because of proximity of the wound or the trajectory of the injuring agent to a major neurovascular bundle. Of the 57 arteriograms obtained because of proximity, 11 identified a vascular injury (19%). Six of these wounds required vascular repair; five patients were treated expectantly. Six of the eight arteriograms obtained for clinical indications were positive (75%), while two were negative (25%). There were no amputations in the study, and all vascular reconstructions were considered successful by clinical and vascular laboratory criteria. One patient died of thoracic injuries; otherwise, all patients were discharged in good condition. Long-term follow-up was not available. In summary, 19% of arteriograms done because of proximity criteria alone identified a clinically occult vascular injury. While only 11% of all proximity arteriograms revealed injuries requiring surgical repair, this rate of significant injury warrants aggressive use of proximity arteriography in a patient population that is prone to poor follow-up.

Adolescent↗
PubMedDate not supplied

Spinal cord grafts: an intraocular approach to enigmas of nerve growth regulation.

The possible usefulness of intraocular transplantation in studies of spinal cord growth and regeneration has been evaluated. Defined segments of fetal rat spinal cord were grafted to the anterior chamber of the eye of adult rats. Such grafts become vascularized from the host iris, grow and develop neuron types, myelinated fiber bundles, astroglial populations (as shown by GFA-immunoreactivity), and electrical activity reminiscent of such features in normal spinal cord tissue. The intraocular technique permits studies of intrinsic circuitries as well as conditions for formation of afferent and efferent connections with the host iris and with other central or peripheral tissues which can be grafted into contact with the spinal cord grafts. One example of an intrinsic system preserved in the grafts is a rich network of nerve fibers with enkephalin-like immunoreactivity. When combined with cerebral cortex, the enkephalin-positive neurons of the spinal cord graft are able to form only very limited projections to the cortex graft. Special emphasis was given the possible formation of adrenergic afferents to spinal cord grafts. No appreciable ingrowth of peripheral sympathetic nerves occurred. Locus coeruleus grafts have many organotypical electrophysiological characteristics and were able to innervate adjacent spinal cord grafts provided that the sensory innervation of the host iris was removed. Experiments such as these suggest that "negative neurotropic" factors may be present in spinal cord and possibly relate to the unique relationship between spinal ganglia and spinal cord.

Adrenergic Fibers↗
PubMed2005

Initial incision of lateral pelvic fascia and early ligation of vascular pedicles during radical prostatectomy: potential to reduce positive margin rates.

OBJECTIVE: To report on our experience with a recently published technique to reduce positive margin (PM) rates (involving early incision of the lateral pelvic fascia, early release of the prostate and Denonvilliers' fascia off the rectum), with the additional modification of early ligation of the lateral vascular pedicles during radical retropubic prostatectomy (RP), as reducing PM rates continues to be an important oncological goal in RP. PATIENTS AND METHODS: One hundred consecutive men (mean age 61 years, pretreatment prostate-specific antigen level 8.9 ng/mL, and estimated blood loss 502 mL) underwent RP by one surgeon. The initial dissection involves early incision of the lateral pelvic fascia and developing the plane between the prostate and underlying rectum, before any apical dissection. This incision can be made medial to the neurovascular bundles in a nerve-sparing procedure. After this plane is developed, the lateral vascular pedicles to the prostate are also divided. Once these same manoeuvres are used contralaterally, the prostate is lifted off of the rectum and held in place only by the apex and bladder neck. The apical/urethral dissection is then carried out conventionally, followed by dissection/transection of the seminal vesicles and the bladder neck. RESULTS: The pathological stage included T2a (11%), T2b (69%), T3a (17%), T3b (3%), and N+ (2%); 20 patients had capsular penetration, at the posterolateral (in 15) and anterior aspect (in five) of the gland. The PM rate for the 100 consecutive patients was 13%, with PMs at the apex in 10, the base in two and posterolateral gland in one. No patient had a PM at the site of capsular penetration. When patients were stratified by low-moderate risk (pT2 and Gleason sum < or = 7) vs high risk (pT3 or Gleason sum > 7), the PM rates were 7.9% and 29.2%, respectively. CONCLUSIONS: Initial dissection of the lateral pelvic fascia, including developing a "perirectal pocket", and early ligation of the lateral pedicles, resulted in a low PM rate during RP. This experience supports the previous observations that early development of the pre-rectal fat plane may allow for more precise dissection below all layers of Denonvilliers' fascia and with a wider margin of periprostatic tissue.

Aged↗
PubMed1983

The 'morning glory syndrome' - a mesodermal defect?

The clinical, ultrasonographic, CAT scan and pathologic findings are described in a case of a rare unilateral malformation involving the optic disc of the type described as the 'morning glory syndrome'. The malformation was associated with a peripapillary scleral defect, absence of the lamina cribrosa and a recess formed by an axial retrodisplacement of the optic nerve. There was an associated secondary exudative retinal detachment with retinal atrophy and gliosis; the retinal pigment epithelium showed peripapillary proliferation. Additional features included: (a) an apparent schisis in the retina within the retrobulbar recess, (b) an absence of the perineural meninges which were replaced by fibroadipose tissue and bundles of smooth muscle, (c) peripheral optic nerve atrophy and (d) a vascular plexus surrounding the central retinal artery.

Child↗
PubMed2006

Chinch bug (Hemiptera: Blissidae) mouthpart morphology, probing frequencies, and locations on resistant and susceptible germplasm.

Chinch bugs are common pests of many agronomic and horticulturally important crops and turfgrasses. Previous research has indicated that some grasses exhibit resistance to multiple chinch bug species, whereas others are resistant to only one species. The objectives of this research were to document differences in the probing frequencies and locations among Blissus species as well as differences in mouthpart morphology as a first step in understanding the differential responses of grasses to chinch bug feeding. Scanning electron microscopy detected differences in the total lengths of proboscises as well as individual mouthpart segments among the four species studied. Blissus occiduus Barber probed significantly more often on buffalograss, Buchloë dactyloides (Nuttall) Engelmann, than any other plant material. Probing locations of B. occiduus and Blissus leucopterus leucopterus (Say) were similar on both B. occiduus-resistant and susceptible buffalograsses and KS94 sorghum, Sorghum bicolor (L.) Moench (B. occiduus-resistant, B. l. leucopterus-resistant). However, on 'Wheatland' sorghum (B. occiduus-resistant, B. l. leucopterus-susceptible), stylet tracts of B. l. leucopterus most often terminated in the bundle sheath cells, whereas those of B. occiduus generally terminated in the vascular tissues.

Animals↗