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PubMed1997

[Clinical application of implantation of vascular bundle into silicone tube to bridge the peripheral nerve defect].

In order to improve the therapeutic effect of non-neural tissue in bridging the peripheral nerve defect and increase the blood supply of the implant, the silicone tube was chosen to bridge the gap, and the vessel bundle was inserted into the tube. The procedures were performed as following: resected the pseudoneuroma and enveloped the proximal and the distal ends in a silicone tube, and then sutured the epineurium and the tube wall with 7/0 stitch. In patients, eleven cases with fifteen nerves were treated, including seven median nerves, five ulnar nerves and three radial nerves. The lengths of the nerve defects were within 3 cm in 13 nerves and 3 cm-5 cm in 2 nerves. They were followed up from one to five years and the result was excellent (M4S4) in 8 nerves, good (M3S3) in 3 and poor (M1S1) in 2. It was discussed that the indication for the procedure should be included: the nerve defect could not be sutured directly, and the patient would not agree to use his own nerve for graft.

Adolescent↗
PubMed1976

[Injuries of the thigh bone with a destruction of the neuro-vascular bundle].

From 1969 to 1971 the authors treated 1360 injured patients, eight of which suffered serious injuries of the thigh; fractured femur complicated by a severed Femoral Popliteal Artery, and lesions of the Sciatic Nerve. Six patients were injured at work, one in an automobile accident, and one was a gunshot victim. In approximately 1000 fractures one is complicated by an injured neurovascular bundle. The clinical picture of such a case is characteristic. The arteriograph is used only to locate the lesion. Reconstruction of the artery must be accomplished some eight to twelve hours following the injury. In all of the authors' cases, this was done one to eight hours following the trauma. After twelve hours, ischemic necrosis of the soft tissue (musculature) sets in requiring amputation. The remaining segment of the damaged artery is usually resected. In one case, a segment 8 cm. long was removed. Following the termino-terminal anastomosis, the injured extremity was placed in a flexed position whlich alleviated the tension on the sutures. The result of vein autographs are worse than those of the termino-terminal anastomoses. Thrombosis later begins to restrict blood flow through the reconstructed artery, but by this time, adequate collateral circulation has been established. The limb has thus been saved. Heparin is administrated immediately before and during the operation in a dosage of 5000 units per 500 ml. of physiological solution. Postoperatively, it is not used as it acts on the fibrin thrombi, and not on the thrombocyte thrombi which are formed postoperatively in the areas where the tunica intima has been damaged. Heparin is indicated in the prophylaxis of venous thrombosis. In these cases in which the femur was fractured, the question asked is whether to perform the osteosynthesis and anastomosis simultaneously, or to perform the former at a later time. The authors chose both methods for various reasons. Only a few cases permitted the authors to decide which approach would be better. Usually they performed a temporary fixation of the bone with Rusch's Pin, and sutured the artery. Four months later, a compressive osteosynthesis using an L-plate, was performed. In four cases, the Sciatic Nerve was injured, which, according to the circumstances was sutured either immediately, or 3 to 4 weeks later. In 3 patients, good functional results were obtained. Three cases resulted in a contracture of the knee, two of which also had residual Sciatic Paresis. One case resulted in permanent venous stasis (edema of the legs, and two cases results in amputation.

Adult↗
PubMed2003

Porcine small intestinal submucosa as a carrier for skin flap prefabrication.

The feasibility of porcine small intestinal submucosa (SIS) as a carrier in skin flap prefabrication was examined in this study. Thirty-eight rats were randomly divided into five groups. The saphenous vascular bundle was used as the vascular carrier. In group 1 (n = 8), an arteriovenous fistula was made by anastomosis of distal saphenous artery and vein. A SIS patch (1.5 x 2 cm2) was placed underneath the vascular bundle. In group 2 (n = 8), the vascular bundle was isolated and laid over the SIS patch. The distal saphenous vessels were ligated when the flap was raised. In group 3 (n = 8), an arteriovenous fistula was made without SIS implant. In group 4 (n = 8), the flap was raised with only the vascular bundle with the distal end ligated. After 2 weeks of maturation, the flap was raised with only the vascular bundle. In group 5 (n = 6), SIS was implanted and the flap including the SIS patch was raised and replaced without the vascular pedicles. The survival of the flaps and histology were evaluated at 5 days after flap replacement. The results showed that the average survival area in group 1 was 99% +/- 3% and the survival area in group 2 was 86% +/- 16%. The mean survival areas in group 3 and 4 were 60% +/- 9% and 25% +/- 10%, respectively. No flap survival was observed in the group 5. These were significantly lower than in groups 1 and 2 (p < 0.05, p < 0.01). Histology showed that SIS patch was incorporated into the adjacent connective tissue and increased amounts of neovascularization were seen between the collagenous sheets and dermis. In conclusion, this study demonstrated that porcine SIS can incorporate into the adjacent tissue and induce angiogenesis in flap prefabrication. This biomaterial can provide a scaffold for supporting and enhancing the survival of vascular prefabricated skin flap.

Animals↗
PubMed2005

A RING domain gene is expressed in different cell types of leaf trace, stem, and juvenile bundles in the stem vascular system of zinnia.

The in vitro zinnia (Zinnia elegans) mesophyll cell system, in which leaf mesophyll cells are induced to transdifferentiate into tracheary elements with high synchrony, has become an established model for studying xylogenesis. The architecture of the stem vascular system of zinnia cv Envy contains three anatomically distinct vascular bundles at different stages of development. Juvenile vascular strands of the subapical region develop into mature vascular strands with leaf trace segments and stem segments. Characteristic patterns of gene expression in juvenile, leaf trace, and stem bundles are revealed by a molecular marker, a RING domain-encoding gene, ZeRH2.1, originally isolated from a zinnia cDNA library derived from differentiating in vitro cultures. Using RNA in situ hybridization, we show that ZeRH2.1 is expressed preferentially in two specific cell types in mature zinnia stems. In leaf trace bundles, ZeRH2.1 transcript is abundant in xylem parenchyma cells, while in stem bundles it is abundant in phloem companion cells. Both of these cell types show wall ingrowths characteristic of transfer cells. In addition, ZeRH2.1 transcript is abundant in some phloem cells of juvenile bundles and in leaf palisade parenchyma. The complex and developmentally regulated expression pattern of ZeRH2.1 reveals heterogeneity in the vascular anatomy of the zinnia stem. We discuss a potential function for this gene in intercellular transport processes.

Amino Acid Sequence↗
PubMed1999

Foliar modifications induced by inhibition of polar transport of auxin.

The effects of auxin polar transport inhibitors, 9-hydroxy-fluorene-9-carboxylic acid (HFCA); 2, 3, 5-triiodobenzoic acid (TIBA) and trans-cinnamic acid (CA) on leaf pattern formation were investigated with shoots formed from cultured leaf explants of tobacco and cultured pedicel explants of Orychophragmus violaceus, and the seedlings of tobacco and Brassica chinensis. Although the effective concentration varies with the inhibitors used, all of the inhibitors induced the formation of trumpet-shaped and/or fused leaves. The frequency of trumpet-shaped leaf formation was related to the concentration of inhibitors in the medium. Histological observation of tobacco seedlings showed that there was only one main vascular bundle and several minor vascular bundles in normal leaves of the control, but there were several vascular bundles of more or less the same size in the trumpet-shaped leaves of treated ones. These results indicated that auxin polar transport played an important role on bilateral symmetry of leaf growth.

Biological Transport↗
PubMed2003

Allene oxide cyclase dependence of the wound response and vascular bundle-specific generation of jasmonates in tomato - amplification in wound signalling.

The allene oxide cyclase (AOC)-catalyzed step in jasmonate (JA) biosynthesis is important in the wound response of tomato. As shown by treatments with systemin and its inactive analog, and by analysis of 35S::prosysteminsense and 35S::prosysteminantisense plants, the AOC seems to be activated by systemin (and JA) leading to elevated formation of JA. Data are presented on the local wound response following activation of AOC and generation of JA, both in vascular bundles. The tissue-specific occurrence of AOC protein and generation of JA is kept upon wounding or other stresses, but is compromised in 35S::AOCsense plants, whereas 35S::AOCantisense plants exhibited residual AOC expression, a less than 10% rise in JA, and no detectable expression of wound response genes. The (i). activation of systemin-dependent AOC and JA biosynthesis occurring only upon substrate generation, (ii). the tissue-specific occurrence of AOC in vascular bundles, where the prosystemin gene is expressed, and (iii). the tissue-specific generation of JA suggest an amplification in the wound response of tomato leaves allowing local and rapid defense responses.

Cyclopentanes↗
PubMed2003

[Development of aloin cells and accumulation of anthraquinone in aloe leaf].

The development of aloin cells and its relationship with the accumulation of anthraquinone in aloe leaf were investigated with the methods of paraffin section, semi-thin section, histochemistry and fluorescent microscopy. The results showed: cells rounded the procambium bundle differentiated into bundle sheath at the initial stage of procambium bundle developing into vascular bundle. When the sieve tube members appeared in protophloem, there were a lay of procambium bundle cells reserved between the sieve tube members and bundle sheath. These cells began to devise, then developed into aloin cells through enlargement of volume and vacuolization with the differentiation of metaphloem and metaxylem. So the aloin cells were special phloem parenchyma cells because they shared the same origin with the other phloem cells. The investigation of histochemistry reflected that there were aloin precipitate in the central vacuole of aloin cells after the material was soaked in the liquid of 1% lead acetate [Pb (CH3COO)2]. In addition, the yellow fluorescence was observed in aloin cells when the section of fresh material was investigated under the fluorescent microscope with blue light, which suggested the aloin cells of vascular bundles were the mainly storage site of anthraquinone.

Aloe↗
PubMed1975

The structural organization of the kidney of the desert rodent Psammomys obesus.

The architecture of the desert rodent Psammomys obesus has been studied by means of standard histologic procedures and by single nephron injections. As other rodent kidneys (rat, mouse), the Psammomys kidney consists of two types of nephrons, 66% short looped and 34% long looped nephrons. The cortex is composed of 4 to 5 layers of glomeruli, which lie closely put together, the glomeruli often touch each other. The superficial and the midcortical glomeruli give rise to short looped neophrons, the juxtamedullary to long looped nephrons. In the strongly developed medulla the inner stripe shows the most striking pattern. It consists of two distinct compartments, that of the giant vascular bundles and that of the interbundle regions. The giant vascular bundles consist of about 8 to 14% arterial vasa recta and 39 to 47% venous vasa recta; furthermore they include the thin descending limbs of the short loops of Henle which amount to 44 to 51% of the bundle structures. The tubules of the interbundle regions surround the bundles in a regular pattern. The inner zone is almost completely surrounded by the renal pelvis; the long broad papilla protrudes into the ureter. The thin descending limbs of short looped nephrons traverse the inner stripe inside the giant vascular bundles. Leaving the bundles they turn back within the inner stripe; their ascending limbs lie in the interbundle region. Both limbs of the long loops of Henle run in the interbundle region, together with the ascending limbs of the short loops and the collecting ducts. The long loops penetrate deeply the inner zone. Many bends are found near the tip of the papilla. The renal pelvis has a very specialized form. It penetrates the inner stripe with many complexely shaped extensions, which surround the giant vascular bundles. Large parts of the bundles with their thin walled structures are thus separated from the pelvic urine only by a single layer of cuboidal epithelium. The possible functional importance of the described specializations of the Psammomys kidney (giant vascular bundles, large inner zone, special shape of the renal pelvis) for the urine concentrating and urea recyclng mechanisms is discussed.

Animals↗
PubMed2005

Structure and development of Medicago truncatula pod wall and seed coat.

BACKGROUND AND AIMS: Medicago truncatula has gained much attention as a genomic model species for legume biology, but little is known about the morphology of its pods and seeds. Structural and developmental characteristics of M. truncatula pod walls and seed coats are presented. METHODS: Plants of M. truncatula ecotype A17 were grown under controlled conditions in a greenhouse. Flowers were date-tagged at anthesis, so that pods of known age could be collected. Harvested pods were fixed and sectioned for light microscopy. Structural attributes of pod walls and seed coats were characterized at four time points throughout early to mid-stages of pod development (3, 6, 13 and 20 d post-pollination). KEY RESULTS: Basic features of the pod wall are an exocarp comprised of a single epidermal layer, a mesocarp with seven to 14 layers of parenchyma cells, and an endocarp composed of an inner epidermal cell layer and three to five layers of sclerenchyma cells adjacent to it. Vascular bundles are abundant in the pod wall and include one lateral carpellary bundle, one median carpellary bundle and nine to 12 vascular bundles, all embedded within the mesocarp parenchyma. Seed coat features include an epidermal layer of macrosclereids, a sub-epidermal layer of osteosclereids, and two to five rows of internal parenchyma cells. The hilar region contains the tracheid bar and the chalazal vascular bundle, the latter of which expands to form only two short branches. CONCLUSIONS: This characterization provides a needed understanding of pod structure and development in this model legume, and should facilitate various molecular investigations into legume fruit and seed biology.

Fruit↗
PubMed1991

[An experimental study to determine the most effective delay procedures on secondary vascularized skin island flaps].

Secondary vascularized flaps made from implanted vascular bundles in the subcutaneous tissues have dominant vascularities. Animal experiments were performed using white rabbits, two types of skin flaps were made on their backs. The first delay procedure was performed on the left side where the vascular bundle had been implanted with an elevation of distally based flap (size 2 cm x 7 cm). 28 out of 32, secondary vascularized skin island flaps survived either partially or completely in the first procedure. Moreover, the first delay method was observed to be efficacious in 15 out of 16 cases (p less than 0.01). The viability of vascular bundles of secondary vascularized flap was thus proved. The first stage of the second delay procedure was performed in bilateral side using the same procedure as the first delay. Two weeks later, two types of delay method were carried out. On the left side, a proximally based flap (size 2 cm x 7 cm) was made at the distal area of the first delay flap. On the right side, a bipedicled flap was made (size 2 cm x 14 cm). These flaps were elevated as secondary vascularized skin island flaps two weeks later. In all cases, the latter procedure produced a longer survival rate compared with the former (p less than 0.01). It was concluded experimentally that the most effective second delay procedure was the bipedicled flap method.

Animals↗
PubMed2004

The unusual vascular structure of the corm of Eriophorum vaginatum: implications for efficient retranslocation of nutrients.

Eriophorum spp. are abundant perennial graminoids in the Arctic tundra and boreal peatlands. Because ecological studies indicated that some plants are unusually productive on infertile and cold sites, the anatomy of the overwintering corms of Eriophorum vaginatum (L.) and Eriophorum scheuchzeri (Hoppe) were examined to determine their involvement in nutrient uptake and storage. Components of the long-distance transport pathways were identified within the plants by using histochemical techniques and transport of apoplastic and symplastic dyes. E. scheuchzeri produced a rhizome that consisted mainly of storage parenchyma cells within which collateral vascular bundles were centrally located and arranged in a circle. By contrast, E. vaginatum developed a ring of horizontally arranged xylem and phloem, in addition to axial amphivasal vascular bundles leading to the leaves, all of which were bordered by transfer cells. As shown by the transport of fluorescein in the phloem and Safranine O in the xylem, each axial bundle and adventitious root contacted the horizontal ring of vascular tissues so that solutes from one vascular bundle were translocated into the vascular ring and circulated to another vascular bundle and/or to the roots. In addition, special groups of sclereids that functioned in both phloem and xylem transport were found at the base of the leaf traces and within junctions of senescing roots. These sclereids were named 'vascular sclerenchyma' and it was hypothesized that they provide a moving end for the vascular system because the corm dies progressively from the distal end as it grows upward from the apical meristem. It was concluded that this unusual vascular system of E. vaginatum is efficient in recycling nutrients internally, which may account for its competitive advantage in infertile and cold sites.

Acclimatization↗
PubMed1992

Vascular bundle-specific localization of cytosolic glutamine synthetase in rice leaves.

Tissue localizations of cytosolic glutamine synthetase (GS1; EC 6.3.1.2), chloroplastic GS (GS2), and ferredoxin-dependent glutamate synthase (Fd-GOGAT; EC 1.4.7.1) in rice (Oryza sativa L.) leaf blades were investigated using a tissue-print immunoblot method with specific antibodies. The cross-sections of mature and senescent leaf blades from middle and basal regions were used for tissue printing. The anti-GS1 antibody, raised against a synthetic 17-residue peptide corresponding to the deduced N-terminal amino acid sequence of rice GS1, cross-reacted specifically with native GS1 protein, but not with GS2 after transfer onto a nitrocellulose membrane. Tissue-print immunoblots showed that the GS1 protein was located in large and small vascular bundles in all regions of the leaf blade prepared from either stage of maturity. On the other hand, GS2 and Fd-GOGAT proteins were mainly located in mesophyll cells. The intensity of the developed color on the membrane for GS1 was similar between the two leaf ages, whereas that for GS2 and Fd-GOGAT decreased during senescence. The tissue-specific localization of GS1 suggests that this GS isoform is important in the synthesis of glutamine, which is a major form of nitrogen exported from the senescing leaf in rice plants.

Journal Article↗