Fungal soil communities in a young transgenic poplar plantation form a rich reservoir for fungal root communities.

Fungal communities play a key role in ecosystem functioning. However, only little is known about their composition in plant roots and the soil of biomass plantations. The goal of this study was to analyze fungal biodiversity in their belowground habitats and to gain information on the strategies by which ectomycorrhizal (ECM) fungi form colonies. In a 2-year-old plantation, fungal communities in the soil and roots of three different poplar genotypes (Populus × canescens, wildtype and two transgenic lines with suppressed cinnamyl alcohol dehydrogenase activity) were analyzed by 454 pyrosequencing targeting the rDNA internal transcribed spacer 1 (ITS) region. The results were compared with the dynamics of the root-associated ECM community studied by morphotyping/Sanger sequencing in two subsequent years. Fungal species and family richness in the soil were surprisingly high in this simple plantation ecosystem, with 5944 operational taxonomic units (OTUs) and 186 described fungal families. These findings indicate the importance that fungal species are already available for colonization of plant roots (2399 OTUs and 115 families). The transgenic modification of poplar plants had no influence on fungal root or soil communities. Fungal families and OTUs were more evenly distributed in the soil than in roots, probably as a result of soil plowing before the establishment of the plantation. Saprophytic, pathogenic, and endophytic fungi were the dominating groups in soil, whereas ECMs were dominant in roots (87%). Arbuscular mycorrhizal diversity was higher in soil than in roots. Species richness of the root-associated ECM community, which was low compared with ECM fungi detected by 454 analyses, increased after 1 year. This increase was mainly caused by ECM fungal species already traced in the preceding year in roots. This result supports the priority concept that ECMs present on roots have a competitive advantage over soil-localized ECM fungi.

Evaluation of chronic venous disease in the lower limbs: comparison of five diagnostic methods.

To compare the usefulness of five diagnostic methods in ensuring deep vein patency, and in demonstrating site(s) of incompetence, 39 patients with clinical signs of chronic venous disease of a leg were included in a study of deep, superficial and perforator veins using triplex ultrasound (TUS), ascending phlebography (AP), descending phlebography (DP), continuous wave Doppler (CWD) and ambulatory strain gauge plethysmography (ASGP). One patient withdrew from the study. It was not possible to use all five methods in all 38 cases, and the methods could only be used partly in some cases. TUS, which allows anatomical, morphological and functional evaluation of the venous system, was chosen as the reference method. There was poor agreement between TUS and AP, and no agreement between TUS and ASGP, in the diagnosis of venous occlusion. AP demonstrated reflux (abnormal valves) in 7 of 22 patients with competent veins at TUS, and missed reflux in 13 of 15 patients with incompetent veins. Similarly, CWD overdiagnosed reflux in 13 of 20 patients and missed the reflux in 3 of 14 patients. DP was only technically possible in 11 patients. ASGP diagnosed venous reflux in all patients with incompetent deep veins, but also indicated deep vein or perforator vein reflux in all but one patient with competent deep veins. The agreement between TUS and the other methods in evaluating reflux in the deep veins was not better than that expected to occur by chance, Cohen's kappa being less that 0.20. It is concluded that AP, CWD and ASGP are of little value in the work-up of patients with deep venous insufficiency.

The terminal complement complex is generated in chronic leg ulcers in the absence of protectin (CD59).

Loss of membrane complement regulators accompanied by complement activation is suggested to be involved in the pathophysiological processes leading to tissue damage in myocardial ischaemia. In the present study we have investigated whether the same phenomenon may occur in ischaemic and/or venous hypertension leg ulcers. The deposition of complement, plasma complement regulators and expression of membrane regulators were detected by immunohistochemical methods, including immunofluorescence with antibodies against C3d, the terminal complement complex (TCC), vitronectin, clusterin, decay-accelerating factor (CD55) and protectin (CD59). Eleven frozen biopsies from ischaemic leg ulcers, 10 biopsies from venous hypertension leg ulcers, and 10 biopsies from normal skin were studied. In 9 of 11 ischaemic and in 5 of 10 venous hypertension leg ulcers, marked staining for TCC was found around the capillaries, most often at the ulcer margin. No TCC staining was found in normal skin. Staining for TCC was always accompanied by staining for clusterin and vitronectin and C3d. In normal skin, CD59 was found on the elastic fibers in the dermis, on the muscle coat, the Schwann sheath and acinar cells. Semiquantitative measurement of CD59 showed marked increased staining intensity in the endothelium in venous hypertension ulcers and diminished intensity in ischaemic ulcers compared to normal skin. No such difference could be observed for CD55. When TCC was positive in the capillary walls, weak or no staining for CD59 was found. A significantly higher ratio of TCC/CD59 was found in the ischaemic compared to venous ulcers (p = 0.018). This was due to a marked difference between the ulcer margins (p = 0.013). Localized areas in the venous ulcers had the same pattern as that seen in the ischaemic ulcers. Our results suggest that loss of CD59 may enhance deposition of TCC and that complement-dependent inflammation may be an important factor in the tissue-damaging processes seen in chronic leg ulcers.

[Healing of venous leg ulcers. A randomized prospective study of a long-stretch versus short-stretch compression bandage]. / Heling af venøse bensår. En randomiseret prospektiv undersøgelse af en langstraek- versus en kortstraek-kompressionsbandage.

The aim of the study was to compare the efficacy of two types of compression bandage with different degrees of elasticity on healing of venous leg ulcers. Forty-three patients with venous leg ulcers were included and blindly randomized to treatment with one of the two types of bandage aiming at a sub-bandage pressure in the ankle area of 40 mmHg. Forty legs were evaluated. Healed ulcers after 12 months were observed in 71% of the long-stretch group and in 30% of the short-stretch group (p = 0.06). Using life-table analysis the predicted healing rate in the long-stretch group after 12 months was 81% and for the short-stretch group 31% (p = 0.03). The mean of relative ulcer areas at 12 months was 0.25 for the long-stretch group and 0.95 for the short-stretch group (p = 0.01). The present study appears to indicate a positive influence of the elasticity of a compression bandage applied with a sub-bandage pressure around 40 mmHg in the ankle area on venous ulcer healing.

Ulcer bed infection. Report of a case of enlarging venous leg ulcer colonized by Pseudomonas aeruginosa.

We report a case of ulcer bed infection in an enlarging venous leg ulcer without clinical signs of cellulitis in the surrounding tissues. Signs of infection in the leg ulcer were: 1) cocci-like structures and bacteria-like rods around vessel walls in the viable ulcer bed, 2) vasculitis-like inflammation of deeply situated vessels of the viable tissue, 3) Pseudomonas aeruginosa-specific antibodies in the serum (other than against exotoxin A), 4) extensive epidermolysis of normal human skin by the wound exudate in vitro, and 5) P. aeruginosa exotoxin A in the wound exudate (23 ng/ml). In an in vitro cell assay, the wound exudate was cytotoxic and rabbit antibodies to exotoxin A, but not a serine proteinase inhibitor, inhibited this cytotoxicity. P. aeruginosa exotoxin A might contribute to the pathogenesis of the ulcer enlargement. The ulcer improved after the third skin graft, probably mainly due to effective treatment with a long-stretch compression bandage.

Subbandage pressure measurements comparing a long-stretch with a short-stretch compression bandage.

Forty-three patients with venous leg ulcers were randomized into treatment with either a long- or a short-stretch compression bandage. Subbandage pressure was regularly measured during rest and walking for a period of up to 1 year. The long-stretch bandage was kept on as long as possible, often up to 1 week. It maintained a significantly higher subbandage pressure in the upright position and during passive dependency as well as during walking than the short-stretch bandage after both 2 and 24 h. The difference between maximum and minimum subbandage pressures during walking did not differ between the two groups. Thus, in contrast to general opinion, the short-stretch bandage did not produce a higher peak working pressure than the long-stretch bandage. The pressure decreased in the supine position in both groups.

[Venous leg ulcer]. / Venøse bensår.

The article summarizes current views regarding venous leg ulcers. Venous ulcers are resource-demanding and affect 1% of the population. Superficial and/or deep venous insufficiency is to be found combined with perforator insufficiency in the ankle are. The pathogenesis is still open to debate, but is presumably related to capillary leakage, with seepage of blood components and ensuing lipodermatosclerosis, as well as to multiple capillary thromboses. Inappropriate leucocyte activation might also play a part. Compression stabilizes capillary function and thus is the cardinal treatment both regarding healing and prophylaxis. In 90% of cases there is no recurrence following superficial vein surgery, so long as the deep veins remain unaffected. In patients with deep venous insufficiency the risk of failure following-such surgery, perforator resection included, is related to the degree of insufficiency. If conventional treatment fails, reconstruction of the deep veins may be considered. Concomitant conditions such as arterial insufficiency and systemic diseases make treatment difficult, and the presence of Pseudomonas aeruginosa may in certain cases delay healing.

Cadexomer iodine in ulcers colonised by Pseudomonas aeruginosa.

The clinical and bacteriological efficacy of topical cadexomer iodine on venous leg ulcers colonised with Pseudomonas aeruginosa was evaluated in an open, uncontrolled, multicentre pilot study. Nineteen patients with venous leg ulcers (median ulcer area 15.5 cm2) were treated with cadexomer iodine paste and short-stretch bandaging for 12 weeks or until the ulcer was healed within that period. Bacteriological cultures for growth of Pseudomonas aeruginosa and ulcer area measurements were regularly performed during the study period. Seven patients were withdrawn during the study period for the following reasons: pain in the ulcer (n = 2), ulcer enlargement (n = 2), treatment of cellulitis in non-study ulcer with a systemic antibiotic that is effective against Pseudomonas aeruginosa (n = 1), increased thyroid-stimulating hormone level (n = 1) and poor compliance (n = 1). In addition, one patient was erroneously withdrawn. After one week's treatment, 11 out of 17 patients (65%) had a negative culture of Pseudomonas aeruginosa. At 12 weeks, six out of eight patients (75%) had a negative culture and complete healing was achieved in three patients (16%). The median ulcer area reduction obtained at 12 weeks was 32.9%. The results indicate that cadexomer iodine paste might be the treatment of choice for venous leg ulcers colonised with Pseudomonas aeruginosa. However, a larger controlled clinical study is needed for final evaluation.

Bacterial colonization and healing of venous leg ulcers.

UNLABELLED: The aim of the study was to evaluate a possible influence of selected bacterial species on healing of venous leg ulcers. Fifty-nine patients with venous leg ulcers were followed via frequent semiquantitative culture of bacteria from the ulcer surface and determination of the ulcer area over a period of 180 days. Occurrences of cellulitis were treated with systemic antibiotics. There was a significant difference in relative areas on days 90 and 180 when ulcers with growth of Pseudomonas aeruginosa were compared to those without (p = 0.0080 and 0.0133, respectively). Ulcers with P. aeruginosa were characterized to a great extent by enlargement in contrast to those without. Ulcers with growth of Staphylococcus aureus or haemolytic streptococci healed significantly more slowly than those without when relative areas were compared on day 180 (p = 0.0079 and 0.0492, respectively). Complete healing within the observation period of 180 days was observed in 10.5% of patients with P. aeruginosa and 35% of those without (p = 0.0631), in 21.6% of patients with S. aureus and 62.5% of those without (p = 0.0278), and in 10.5% of patients with haemolytic streptococci and 35% of those without (p = 0.0631). The initial areas of ulcers colonized with P. aeruginosa or S. aureus were significantly larger than those without, but no significant correlation between initial areas and ulcer healing was revealed. CONCLUSION: Our results suggest that P. aeruginosa in venous leg ulcers can induce ulcer enlargement and/or cause a healing delay. The results also suggest a healing delay caused by S. aureus and haemolytic streptococci. However, conclusions have to be treated with caution since P. aeruginosa was found in combination with haemolytic streptococci in 15.3% of the patients.

High-frequency ultrasound for torture-inflicted skin lesions.

Objectivity, reproducibility and non-invasiveness are required for a medico-legal evaluation of skin lesions in torture victims. In this report we describe the use of the high-frequency method for imaging of scars presumed to be inflicted by torturing. The extent of scarring and the size of the lesions could be determined precisely and objectively. We suggest that skin ultrasonography may be a useful supplementary method for evaluation of skin changes in torture victims.

Vein surgery with or without skin grafting versus conservative treatment for leg ulcers. A randomized prospective study.

In order for us to evaluate the efficiency of perforator vein surgery and skin grafting in leg ulcer patients, 47 patients were randomized into 3 treatment groups (group A: surgery for incompetent perforators, group B: surgery for incompetent perforators and ulcer excision followed by grafting, group C: control group). All the patients were treated with a compression bandage. When cellulitis was observed, a systemic antibiotic was given; eczema was treated with a steroid ointment. Fourty patients were evaluated regularly during one year after entry. There were no differences between the 3 treatment groups considering base-line characteristics, median ulcer size at entry and after one year. According to a review of the initial phlebograms, the occurrence of post-thrombotic changes in the deep veins were recorded in the majority of the legs. Our results suggest that ligation of incompetent perforators and skin grafting, as used in the present study, may not offer an additional advantage for venous ulcer patients with insufficiency of the deep veins when compared to conservative treatment. However, the removal of insufficient superficial veins was not studied.

The occurrence of pericapillary fibrin in venous hypertension and ischaemic leg ulcers: a histopathological study.

The presence of pericapillary fibrin and complement C3c in the ulcers of 19 patients with venous hypertension and 14 patients with ischaemic leg ulcers was investigated using histochemical and immunohistochemical techniques. There was deposition of fibrin around the capillaries in the central part of the ischaemic ulcers, and the venous hypertension ulcers, and in the non-ulcerated skin around one of the venous hypertension ulcers and two of the ischaemic leg ulcers. The deposition of fibrin is a secondary phenomenon that occurs in the area of ulcerated skin and does not play a major causal role in the formation of chronic leg ulcers.

Diagnosis of electrical skin injuries. A review and a description of a case.

This paper presents a brief review of the results of research in the area of electrical skin injuries. It also includes a case report of a 5-year-old girl noted on her admission to the hospital to have injuries to the skin of her chest and left arm. Histological examinations demonstrated that the skin lesions were segmental and showed necrosis and inflammation. Deposits of calcium salts distinctly located to collagen fibers were observed below the regenerated epidermis at the periphery of two skin lesions of the chest wall, in the lower part of dermis at the periphery of a skin lesion of the left arm, and within connective tissue adjacent to elastic arteries and peripheral nerves from the thoracic cavity. The pattern of calcification localized to collagen fibers and situated both superficially and deeply in the skin in a zone of viable tissue close to necrotic tissue is characteristic of electrically induced lesions. Although there have been reports of deposition of calcium salts on collagen fibers after application of calcium salts in high concentration at the skin surface, the collagen calcification in the pattern observed in this patient is probably diagnostic of electrical injury.

Lower leg subcutaneous blood flow during walking and passive dependency in chronic venous insufficiency.

The blood flow in the subcutaneous adipose tissue of the lower leg of eight normal subjects and 19 patients with chronic venous insufficiency was measured. The 133Xe-washout technique was used with portable CdT1(C1) detectors and a data storage unit. Only those patients with ulcers and a systolic blood pressure at the toe of greater than or equal to 60 mm were investigated. In the controls the relative blood flow during sitting was 0.61 (range 0.35-0.80). In the patients it was 0.46 (range 0.22-0.87). This difference was not significant. During walking the blood flow increased in controls as well as in the patients compared to the value determined in the sitting position (P = 0.0078 and P = 0.0028, respectively, Wilcoxon matched-pairs test). The relative blood-flow rate during walking was 0.96 (range 0.60-1.58) in the controls, and 1.04 (range 0.49-1.46) in the patients. The difference between the normal subjects and the patients was not significant (P = 0.79). We conclude from our studies that patients with venous insufficiency are able to increase their blood flow during walking to the same extent as normal controls.