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At least 253 records · Page 14Linked to original sources
PubMed1983

Hexosaminidase: a marker for intestinal gangrene in necrotizing enterocolitis.

Detection of intestinal ischemia, prior to necrosis, is a major clinical problem. The lysosomal acid hydrolase, hexosaminidase (HEX), is known to be elevated in intestinal infarction. To determine if this enzyme could differentiate between partial intestinal ischemia and full-thickness intestinal gangrene, the following rat study was designed. Partial segmental intestinal ischemia was created by ligating alternate vascular bundles over a short (6 vessel) segment of the small-bowel mesentery, and complete segmental intestinal vascular occlusion was achieved by ligating the blood supply to the ileocecal segment. Preoperative serum HEX values were obtained from 15 animals. The rats were separated into one sham-operated and two intestinal ischemia groups. At four hours after surgery HEX values were determined. Total HEX activity was significantly elevated four hours after insult in both partial and complete intestinal ischemia, (P less than 0.005 and P less than 0.001 respectively). Total HEX activity was greater in complete intestinal ischemia than in partial ischemia, (P less than 0.05). Three neonates with intestinal perforation, secondary to necrotizing enterocolitis, were evaluated. The mean preoperative HEX activity was 1421 nmol/hr/mL serum and the mean post-resection HEX activity was 808 nmol/hr/mL serum. These data suggest that serum HEX activity may be a good marker for intestinal gangrene in neonates with necrotizing enterocolitis.

Animals↗
PubMed1988

Ethylene effect on extensin and peroxidase distribution in the subapical region of pea epicotyls.

In dark grown pea (Pisum sativum) seedlings ethylene causes the triple response in which elongation growth is inhibited, radial growth is promoted, and orientation of shoots to gravity is altered. The distribution of extensin and peroxidase activity in pea epicotyls upon ethylene treatment was studied by tissue printing on nitrocellulose paper. It was found that the localization of extensin and peroxidase activity changes after 72 and 96 hours of ethylene treatment. In untreated plants, peroxidase activity is detected only in the vascular bundles. Nonetheless, after 72 and 96 hours of ethylene treatment peroxidase activity is hardly detected in the vascular system but present in the epidermal and cortical cells. Extensin increases in the epidermal and cortical cells upon ethylene treatment but it also appears in the vascular system when peroxidase activity is no longer detected.

Journal Article↗
PubMed2002

[Saving surgical time with great hemostatic safety and efficiency using the LIGA-SURE system in complete pelvic urologic surgery].

OBJECTIVE: To achieve an effective, safe and fast hemostasis. To translate it into a great diminution of operating time, avoiding multiple ligatures that are time consuming and being merely a mechanical, repetitive act do not add any element of quality to surgery in general and to urologic pelvic procedures in particular. METHODS: A new hemostatic system has been experimented in pelvic urologic open surgery, specifically in radical cystectomy (RC) (with orthotopic substitution or urinary diversion) and radical prostatectomy (RP). It achieves vascular sealing by means of tissue collagen precipitation when applied in previously dissected vascular pedicles during radical cystectomy and neuro-vascular bundles during radical prostatectomy. RESULTS: It has been noted a complete efficacy in the coagulation of all vascular pedicles as well as a significant decrease in operating time (around 25%) because the use of ligatures is completely avoided. It has also been noted a great decrease in blood loss, with reductions in transfusion needs down to 50% of the cases. CONCLUSIONS: The new hemostatic system by tissue collagen coagulation allows a fast, effective and safe hemostasis in complex urological pelvic surgery, which translates into operative time savings and minimal blood loss.

Adenocarcinoma↗
PubMed2002

[The effect of basic fibroblast growth factor (bFGF) on neovascularization and prefabricated flap survival].

OBJECTIVE: To observe the effect of basic fibroblast growth factor (bFGF) on neovascularization and prefabricated flap survival. METHODS: Male New-Zealand rabbits weighting 2.0-2.5 kg were used in this study. The experimental model used a prefabricated neck flap, supplied by the transferred and implanted central vascular bundle of the ear. 9 micrograms bFGF and 0.2 ml of normal saline was instilled in the vascular pedicle of the experimental and the control group respectively. After 1, 2, 3 weeks of operation, the neovascularization was studied by confocal laser scanning microscope (CLSM) and flap survival was observed. RESULTS: The neovascularization and survival of the prefabricated flap was different in the experimental and the control groups. The experimental group was better than the control group. CONCLUSION: bFGF treatment improved sprouting of the implanted vessel and the prefabricated flap survival.

Animals↗
PubMed1989

[Donor tissue source in plastic surgery of the hand].

From topographic and anatomical examination of 32 upper limbs the authors proved that an island skin-fascia graft supplied with blood by the septocutaneous branches of the posterior interosseous vascular bundle can be formed on the posterior aspect of the forearm. Such a graft on a peripheral vascular pedicle was transplanted in 6 patients with defects in the integumentary tissues of the hand; it healed completely in 4 cases, peripheral necrosis occurred in 2 cases but did not affect the end result. The use of means of optic magnification and prevention of compression of the vascular pedicle in the postoperative period ensure successful transplantation of the graft.

Adult↗
PubMed2005

Phloem and xylem specification: pieces of the puzzle emerge.

The plant vascular system is composed of two tissue types, xylem and phloem, which originate from the vascular meristem, the procambium. Recently, several regulatory mechanisms that control the specification of these two tissue types have been uncovered. These include the asymmetric patterning of xylem and phloem in the vascular bundle by the class III HD-ZIP and KANADI genes, the tissue-type-specific control of vascular cell proliferation by brassinosteroids and class III HD-ZIP genes, the regulation of vascular tissue identity by the MYB-like transcription factor APL, and inductive signalling during xylem differentiation by xylogen. These findings define an emerging developmental framework for the control of vascular tissue specification.

Body Patterning↗
PubMed2005

Leaf and stem morphoanatomy of Petiveria alliacea.

Petiveria alliacea is a perennial herb native to the Amazonian region and used in traditional medicine for different purposes, such as diuretic, antispasmodic and anti-inflammatory. The morphoanatomical characterization of the leaf and stem was carried out, in order to contribute to the medicinal plant identification. The plant material was fixed, freehand sectioned and stained either with toluidine blue or astra blue and basic fuchsine. Microchemical tests were also applied. The leaf is simple, alternate and elliptic. The blade exhibits paracytic stomata on the abaxial side, non-glandular trichomes and dorsiventral mesophyll. The midrib is biconvex and the petiole is plain-convex, both traversed by collateral vascular bundles adjoined with sclerenchymatic caps. The stem, in incipient secondary growth, presents epidermis, angular collenchyma, starch sheath and collateral vascular organization. Several prisms of calcium oxalate are seen in the leaf and stem.

Calcium Oxalate↗
PubMedDate not supplied

Detection of Aspergillus flavus penetration in tree nuts using fluorescent antibody technique.

Indirect fluorescent antibody technique was used for the detection of A. flavus entry in pistachio nuts where the kernel is protected with a hard, usually nonsplit, shell. Sound nuts were inoculated with a toxigenic species of A. flavus and stored at 88% RH for three weeks at 29 degrees C. Aflatoxins could be detected in the kernels at a level of 65 micrograms/kg at the end of this period. Antisera for A. flavus was produced using female New Zealand white rabbits. Cross sections of various parts of the shell were treated using indirect fluorescent antibody technique. Microscopic examinations revealed mycelial fragments only in sections taken from the vascular system. Presence of fluorescent mycelial fragments in the vascular bundles indicate that fungal invasion of tree nuts which are protected with a hard shell take place through the vascular system.

Aspergillus↗
PubMed1998

Tissue localization of expansins in deepwater rice.

Expansins are a family of proteins capable of inducing stress relaxation of isolated cell walls. In earlier studies, we showed that the expression of expansin genes in deepwater rice (Oryza sativa L.) is regulated by developmental, hormonal and environmental stimuli. Here, we describe the spatial distribution pattern of expansin transcripts and proteins in tissues and organs of deepwater rice using in situ mRNA hybridization and immunohistochemical analysis. Expansin transcripts and proteins are present at high levels in the growing internodal epidermis, which has thick cell walls and acts, therefore, as a growth-limiting cell layer. Expansins are also concentrated in the differentiating vascular bundles of internodes. In the primary root, expansins are predominantly expressed in the tip region, particularly in the epidermis, differentiating vascular cylinder, and around the pericyle. Developing adventitious roots and lateral root primordia also contain high levels of expansin mRNA. In the shoot apex, expansin transcripts are abundant in the emerging leaf primordia. Our results indicate that expansins play an important role in the expansion and differentiation of plant tissues and organs.

In Situ Hybridization↗
PubMed1980

Scanning electron microscopical study of tracheal vascularization in guinea pig.

In view of a considerable increase of the tracheal injuries brought about by intubation, further detailed information on microcirculation of the trachea is needed. For this purpose, the normal microvascularization of the guinea pig trachea was investigated in microcorrosion casts viewed in a scanning electron microscope. The trachea is supplied by longitudinal vascular bundles running at both sides of the organ, including both longitudinal tracheoesophageal arteries and veins. They are the source of a segmental vascularization of the trachea. Due to numerous arteriovenous anastomoses and anastomoses occurring within respective arterious and venous vascular systems, a constant blood flow within submucous capillary plexus and the tracheal wall is provided. A characteristic feature of tracheal vascularization is a very rich, dense network of veins, which form well-developed plexuses, particularly in tracheal segments covered by skeletal cartilages.

Animals↗
PubMed2000

Limb salvage in lower-extremity sarcomas and technical details about vascular reconstruction.

Vascular surgery may allow limb salvage when a sarcoma of the lower limb involves the main vascular bundle. We present our experience and describe the techniques which have been employed for such surgery. From October 1995 to April 1999, vascular surgery procedures were employed in seven patients with sarcomas of the thigh: two complete subadventitia dissections of the main vascular trunks, four artery replacements (two polytetrafluoroethylene [PTFE] grafts and two autologous saphenous grafts), and five venous reconstructions (all with autogenous saphenous graft: three substitutions; two distal transpositions with one external rigid support at the anastomosis). Clinical and instrumental (sonogram, computed tomography [CT] scan, echodoppler) follow-up was carried out at 3, 6, and then every 12 months after surgery (mean, 25 months; range, 6-53 months). Operative mortality and morbidity were nil. All the grafts were patent (one arterial thrombosis was successfully treated on the first postoperative day). The functional result was good in six patients and fair in one. Two patients died, 24 and 13 months after surgery, with disseminated disease, but had no local recurrence. Five patients are alive and disease-free. Vascular techniques allow limb salvage with en-bloc resection of sarcomas of the thigh involving the main vessels. Venous reconstructions are indicated after removal of both the superficial and deep femoral veins. We suggest limiting the number of anastomoses (two transpositions in our series) and using external rigid support in those patients with a small saphenous vein graft (one patient in our series).

Adult↗
PubMed2003

Photosynthetic enzyme accumulation during leaf development of Arundinella hirta, a C4 grass having Kranz cells not associated with veins.

The leaf of the NADP-malic enzyme type C(4) grass, Arundinella hirta, has not only mesophyll cells (MCs) and bundle sheath cells (BSCs, usual Kranz cells) but also another type of Kranz cells (distinctive cells; DCs) that are not associated with vascular bundles. We investigated photosynthetic enzyme accumulation along the base-to-tip maturation gradient of developing leaves by immunogold electron microscopy. In mature leaves, phosphoenolpyruvate carboxylase (PEPC) and ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) were detected in the MC cytosol and in the BSC and DC chloroplasts, respectively. Pyruvate, P(i) dikinase (PPDK) was present in the chloroplasts of all photosynthetic cells but with higher levels in the MCs. Rubisco was first detected in the basal region of emerging leaf blades where the BSCs and DCs became discernable. Subsequently, the accumulation of PEPC and PPDK was initiated in the region where the granal proliferation in the chloroplasts was conspicuous; and, suberized lamellae were formed in the cell walls of the Kranz cells. There was no difference in the patterns of cellular development and enzyme accumulation between the BSCs and DCs or between the MCs adjacent to each type of Kranz cells. These results demonstrate that, although the DCs are not associated with veins, they behaved like BSCs with respect to enzyme induction and cellular differentiation.

Biological Transport↗
PubMed1972

Lateral movement of water and sugar across xylem in sugarcane stalks.

Laterally connected vascular bundles in the nodes of sugarcane (Saccharum species cv. Pindar) stalks allow a rapid redistribution of water across the stalk should the vascular continuity be partly disrupted. Tritiated water supplied to the roots exchanged rapidly between the xylem and storage tissue so that net movement up the stalk was slow. The half-time for exchange in a labeled stalk was about 4 hours so that the entire water content of a sugarcane stalk can turn over at least once in a single day. No rapid flux of sugar between xylem and phloem or xylem and storage tissue was detected. Functional xylem contained only low sugar concentrations: less than 0.3% w/v in the stalk and less than 0.02% w/v in the leaf. Previous reports of high sugar levels (9% w/v) in sugarcane stalk xylem reflect some degree of xylem blockage followed by a slow equilibration with free space sugars in the storage tissue.

Journal Article↗
PubMed1983

Localization of lipoxygenases 1 and 2 in germinating soybean seeds by an indirect immunofluorescence technique.

Lipoxygenases 1 and 2 were localized in etiolated germinating soybean seeds (Glycine max [L.]. Merr. var. Williams) by an indirect immunofluorescence staining technique. Sections of paraffin-embedded seedlings were stained with affinity-purified antibodies directed against lipoxygenase 1 or 2. The specificity of the immunofluorescence technique was examined by use of nonimmune serum or immunoglobulin G preparations after total adsorption with the appropriate lipoxygenase coupled to Sepharose 4B.After immunofluorescence staining with antilipoxygenase 1 or 2 IgG storage tissues of cotyledons fluoresce strongly the first days of germination. After 3 days, the abaxial hypodermis, the epidermis, and the vascular bundle sheaths show fluorescence, especially after incubation with antilipoxygenase 2 IgG. Fluorescence in cortex and pith of the hypocotyl migrates to the vascular cylinder during germination. In primary leaves, all tissues show fluorescence after 1 day of germination. In storage tissues of cotyledons, cytoplasm around the protein bodies fluoresces, whereas in other tissues protein bodies or other large cell organelles fluoresce.It is reasonable to suggest that lipoxygenase exerts its function in cells at the time that rigorous changes in metabolism take place, namely at the start of mobilization of reserves in storage tissues and start of biosynthesis of chloroplastids in several tissues.

Journal Article↗
PubMed1994

[Scanning electron microscopical study of trachea vasculature in the human fetus].

The microvasculature of the human fetal trachea was studied in vascular casts viewed in a scanning electron microscope (SEM). The trachea is supplied by longitudinal vascular bundles running at both sides of the organ, including both longitudinal tracheoesophageal arteries and veins. They are the source of the segment vascularization of the trachea. Due to numerous arteriovenous anastomoses and anastomoses occurring within respective arterious and venous vascular systems, a constant blood flow within submucous capillary plexus and the tracheal wall is provided. A characteristic feature of tracheal vascularization is a very rich, dense network of vein.

Corrosion Casting↗
PubMed2003

Auxin distribution in Lotus japonicus during root nodule development.

For this work, Lotus japonicus transgenic plants were constructed expressing a fusion reporter gene consisting of the genes beta-glucuronidase (gus) and green fluorescent protein (gfp) under control of the soybean auxin-responsive promoter GH3. These plants expressed GUS and GFP in the vascular bundle of shoots, roots and leafs. Root sections showed that in mature parts of the roots GUS is mainly expressed in phloem and vascular parenchyma of the vascular cylinder. By detecting GUS activity, we describe the auxin distribution pattern in the root of the determinate nodulating legume L. japonicus during the development of nodulation and also after inoculation with purified Nod factors, N-naphthylphthalamic acid (NPA) and indoleacetic acid (IAA). Differently than white clover, which forms indeterminate nodules, L. japonicus presented a strong GUS activity at the dividing outer cortical cells during the first nodule cell divisions. This suggests different auxin distribution pattern between the determinate and indeterminate nodulating legumes that may be responsible of the differences in nodule development between these groups. By measuring of the GFP fluorescence expressed 21 days after treatment with Nod factors or bacteria we were able to quantify the differences in GH3 expression levels in single living roots. In order to correlate these data with auxin transport capacity we measured the auxin transport levels by a previously described radioactive method. At 48 h after inoculation with Nod factors, auxin transport showed to be increased in the middle root segment. The results obtained indicate that L. japonicus transformed lines expressing the GFP and GUS reporters under the control of the GH3 promoter are suitable for the study of auxin distribution in this legume.

Alphaproteobacteria↗
PubMedDate not supplied

Capillary vessel network integration by inserting a vascular pedicle enhances bone formation in tissue-engineered bone using interconnected porous hydroxyapatite ceramics.

The aim of the present study was to investigate the possibility of integrating porous hydroxyapatite (HA) ceramics with a capillary vessel network via insertion of a vascular pedicle, and to determine whether this procedure enhances new bone formation in tissue engineering of bone. First, synthetic interconnected porous HA (IP-CHA) was implanted subcutaneously into rat groin with or without insertion of superficial inferior epigastric vessels. At 6 weeks, IP-CHA with vascular insertion contained thick fibrous connective tissue with a number of large blood vessels that seemed to derive from the inserted vascular bundle. Next, IP-CHA loaded with recombinant human bone morphogenetic protein 2 (BMP, 2 or 10 microg/block) was implanted with or without vascular insertion. At 3 weeks, IP-CHA/BMP (10 microg) composite with vascular insertion exhibited abundant new bone formation in the pores of the deep portion close to the inserted vessels. In contrast, IP-CHA/BMP (10 microg) without vascular insertion showed poor bone formation. Histomorphometric analysis demonstrated that vascular insertion significantly increased new bone formation. In IP-CHAs with a lower dose of BMP (2 microg), no bone formation was found, with or without vascular insertion. These results suggest that the present system of integrating a vascular network with IP-CHA is a useful technique for bone tissue engineering.

Animals↗
PubMed1990

[CT of gold pneumonitis].

We experienced five cases of gold pneumonitis. CT findings of four cases and pathological findings of an autopsy case were discussed. CT findings of gold pneumonitis could be classified as follow; (1) high density shadow of subpleural zone-BOOP suspected- (2) high density shadow along the broncho-vascular bundle (3) small cystic shadow of subpleural zone-UIP. Histological findings of an autopsy case revealed the fibrosis along the broncho-vascular bandle. A variety of radiologic and pathologic feature on the gold pneumonitis were seen.

Adult↗