Effects of three months of low molecular weight heparin (dalteparin) treatment after bypass surgery for lower limb ischemia--a randomised placebo-controlled double blind multicentre trial.

OBJECTIVES: To test the hypothesis that long-term postoperative dalteparin (Fragmin), Pharmacia Corp) treatment improves primary patency of peripheral arterial bypass grafts (PABG) in lower limb ischemia patients on acetylsalicylic acid (ASA) treatment. DESIGN: Prospective randomised double blind multicenter study. MATERIALS AND METHODS: Using a computer algorithm 284 patients with lower limb ischemia, most with pre-operative ischemic ulceration or partial gangrene, from 12 hospitals were randomised, after PABG, to 5000 IU dalteparin or placebo injections once daily for 3 months. All patients received 75 mg of ASA daily for 12 months. Graft patency was assessed at 1, 3 and 12 months. RESULTS: At 1 year, 42 patients had died or were lost to follow-up. Compliance with the injection schedule was 80%. Primary patency rate, in the dalteparin versus the control group, respectively, was 83 versus 80% (n.s.) at 3 months and 59% for both groups at 12 months. Major complication rates and cardiovascular morbidity were not different between the two groups. CONCLUSIONS: In patients on ASA treatment, long-term postoperative dalteparin treatment did not improve patency after peripheral artery bypass grafting. Therefore, low molecular weight heparin treatment cannot be recommended for routine use after bypass surgery for critical lower limb ischemia.

Acetone has anti-inflammatory effects on experimental contact reactions.

The effects of a topically applied corticosteroid and its acetone vehicle on experimental allergic, toxic and irritant reactions are presented. The corticosteroid budesonide in acetone or acetone alone was applied to reactions immediately after and at different time intervals within the 1st h after provocation. Classical naked eye observation was performed and the dermal cellular infiltrate was differentiated and counted using a previously well-characterized method. "Treatment", whether with the steroid in acetone or acetone alone, had anti-inflammatory effects. For all reaction types, erythema and oedema diminished and a significant decrease in mononuclear cells was seen, when application occurred within the first 5 min after provocation. The effects were most marked for the toxic reaction to croton oil, the steroid and the vehicle being anti-inflammatory to the same extent. Application up to 60 min after provocation had anti-inflammatory effects for this reaction type. The mechanisms of acetone's anti-inflammatory effects are at present unclear. One possible explanation is that intercellular lipid organisation and, by extension, cellular membrane lipid organisation, are altered, influencing membrane receptor function. Possible anti-inflammatory effects of acetone should be considered in experimental and perhaps even clinical situations. Further investigation of the therapeutic possibilities of the finding seems warranted.

Regulation of insulin-like growth factors and IGF-binding proteins in bone tumours.

Insulin-like growth factors (IGFs) and IGF-binding proteins (IGFBPs) are important regulators of growth and development in normal bone and bone tumours. IGFs contribute to about 50% of basal bone cell proliferation. Their mitogenic actions is either enhanced or inhibited by specific IGFBPs which are also regulated by a variety of factors. This system is further complicated by the presence of specific proteases for IGFBPs. Serine proteases are secreted by malignant bone tumours and the hydrolysis of IGFBPs increases the bioavailability of IGFs. In addition, the autocrine production of IGFs may facilitate the development of bone tumours and metastatic lesions.

The cellular dermal infiltrate in experimental immediate type cutaneous hypersensitivity.

A previously developed guinea pig model for the study of the dermal inflammatory cell infiltrate of allergic, toxic, and irritant reactions was adapted to the study of the immediate intradermal reaction to ovalbumin. Comparison of qualitative and quantitative counts of infiltrating cells at three levels in the dermis showed that counting 20 subepidermal fields starting from the injection point of the allergen gave reliable figures. The reaction showed microscopically two phases. The first was of rapid onset and characterized by a high proportion of neutrophils, unlike the picture seen in the previously studied (allergic and toxic) reaction types. In the second phase, which can be termed "late phase" reaction, mononuclear cells and basophil granulocytes predominated. The late phase of the reaction bears similarities to the delayed allergic contact reaction at the same timepoint in that the response was rich in basophils. There were, however, other differences; e.g. eosinophils and neutrophils were more common.

Delayed hypersensitivity responses in children after local cutaneous anesthesia.

The effect of cutaneous analgesia on delayed type hypersensitivity (DTH) reactions as challenged by injections in the skin was assessed by comparing a lidocaine/prilocaine mixture with placebo. Application of 5 g of the mixture 90 min before testing significantly (p less than 0.001) reduced pain but did not influence the DH-reactions as read after 48 hours. Based on these findings, DTH to several antigens were measured in 116 school children, aged 7-15 years. All the children were positive to either tetanus antigen, 7.5 Lf/ml (98% at 48 hours) or mumps test antigen (82%), while positivity to tuberculin 2 TU/ml and candida 1000 PNU/ml were only 11 and 62% respectively. Therefore, DTH tests in an adequately immunized population of children can be limited to two antigens. Application of cutaneous analgesia is recommended as a routine procedure in DTH testing in young children.

Animal model for assessment of skin irritancy.

Irritant skin reactions from repeated open applications of low concentrations of sodium lauryl sulphate (SLS) have been studied macroscopically and microscopically in guinea pigs. After 3 applications daily for 3 days, 2% SLS aqueous solutions gave a naked eye assessment, increase in epidermal thickness and total dermal inflammatory cell response, which was greater than for a 1% SLS solution. The dermal inflammatory cell response was mainly mononuclear (lymphocytic) in nature. With the SLS reactions as control, various organic solvents were studied and ranked against the SLS reactions and internally. Trichlorethylene was the most irritant solvent, ranking as high as 2% SLS. Other chlorinated hydrocarbons and aromatic hydrocarbons tested caused irritant reactions. The alcohols and acetone gave no reaction. White spirit was as irritant as trichlorethylene. Thinners were less irritant, around the level of the 1% SLS control reaction. The 4-day experimental design is a convenient and suitable animal model for screening irritant potential, and provides information relevant to the pathogenesis of irritant contact reactions.

The effect of cyclophosphamide on the allergic contact reaction in guinea pig: dose effects and influence on peripheral blood.

Single intraperitoneal injections of cyclophosphamide were administered 6 days before testing guinea pigs sensitized to oxazolone in order to study the effects on inflammatory cell populations in blood and dermis. Skin tests were assessed macroscopically (erythema and oedema) and microscopically (counting of the dermal inflammatory cell infiltrate). At the highest dose (300 mg/kg) the allergic contact reaction was augmented with increases in erythema and oedema and the mononuclear dermal infiltrate. At the lowest dose (75 mg/kg), redness and oedema and all components of the dermal inflammatory cell infiltrate decreased. Total and differential white blood counts up to 20 days after administration of cyclophosphamide showed that a dose-dependent leukopenia maximal around 6 days occurred. During the leukopenia the differential count showed a lymphocytosis with a marked granulocyte depletion. The augmentation of the contact allergic reaction produced at the highest dose of cyclophosphamide occurs despite a marked peripheral blood leukopenia. Cyclophosphamide's effects at the lower dose would appear to be of a non-specific anti-inflammatory nature.

The effect of cyclophosphamide on the toxic contact reaction to croton oil in guinea pig.

Cyclophosphamide is a cytostatic agent used clinically and in experimental studies for its immunosuppressant effect. Effects on the afferent and efferent limb of the contact allergic reaction have been shown. The substance has also non-specific, anti-inflammatory effects and these were investigated in this paper by studying the effects of single doses of cyclophosphamide on the toxic contact reaction to croton oil (a non-specific inflammatory reaction) in guinea pig. Counting of the dermal cellular infiltrate showed that mononuclear and granulocyte counts decreased in a dose-dependent fashion after cyclophosphamide administration. Erythema and oedema in the test reactions decreased generally, although at the highest dose a paradoxical increase was seen.

Cytostatic agents and contact allergy: the efferent limb.

The effects upon the contact allergic reaction in the guinea pig of the 3 cytostatic agents most commonly used for their immunosuppressant properties, cyclophosphamide, methotrexate and azothioprine, have been investigated in an experimental model which allows comparison of the qualitative and quantitative aspects of the dermal inflammatory infiltrate and the macroscopic response. The 3 agents were given in single, relatively high doses and had effects on the dermal inflammatory infiltrate which varied in nature, degree and time course. Changes often showed a cyclical development with time, with "rebound" often following initial changes. Although cyclophosphamide had the most marked effect, all agents affected the mononuclear, basophil and eosinophil dermal infiltrates at some point in the experiment. Cyclophosphamide was the only agent found to affect the total white cell count of peripheral blood, but the leukopenia did not affect recruitment of mononuclear cells to the dermis. In the period immediately after administration of cyclophosphamide and methotrexate, the macroscopic score increased. Whilst the mechanism of this effect is unclear, it may be a manifestation of a basophil, perhaps IgE mediated reaction. Further manipulation of dose and dose interval may result in administration schedules relevant to the treatment of cell-mediated hypersensitivity in clinical practice.

Suppression of the allergic contact reaction in the guinea pig by cyclosporin A.

In a study of the effects of cyclosporin A on the allergic contact reaction to oxazolone in the guinea pig, a pronounced ability to suppress redness and edema and the dermal inflammatory cell infiltrate was demonstrated. At the generally recommended (human) organ transplantation immunosuppression dosage (20 mg/kg), a single dose gave no certain effect, but when repeated daily for 3 days, some suppression of the reaction was seen. A single 80 mg/kg dose produced marked suppression of erythema and edema and all components of the dermal cellular infiltrate. This effect was still evident, though less marked, 3 days after administration. The 80 mg/kg dose had no effect on the toxic contact reaction to croton oil. Of the agents we have previously tested (cyclophosphamide, methotrexate and azathioprine) with this model, cyclosporin A has by far the most marked capacity to suppress the allergic (cell-mediated) contact reaction, via a mechanism which would appear to involve immunomodulation rather than mere nonspecific anti-inflammatory effects.

The influence on the dermal cellular infiltrate of topical steroid applications and vehicles in guinea pig skin: normal skin, allergic and toxic reactions.

The mechanisms of the anti-inflammatory effects of corticosteroids are uncertain but could be explained by an influence on infiltrating leukocytes. Our method for the qualitative and quantitative investigation of the dermal cellular infiltrate makes it possible to study the effects of topically applied corticosteroid preparations and vehicles on the infiltrating leukocytes of normal skin, allergic and toxic reactions in guinea pig skin. Ointment and cream vehicles as well as corticosteroid cream and ointment preparations often caused erythema and increased mononuclear infiltrate after only short periods of application (24-72 h). The strongest steroid ointment gave the most marked macroscopic response and propylene glycol preparations the most marked cellular response. In both toxic and allergic reactions, application of steroid preparations after the provocation gave no beneficial result either macroscopically or microscopically. Macroscopic scores were worsened by cream and ointment preparations. Although steroid solutions had no beneficial effect, they caused no detrimental effect. The guinea pig seems to be extremely sensitive to irritants and has not proved to be a suitable model for this approach to the study of the efficacy of topically applied steroids.

Delayed hypersensitivity. A critical evaluation of five recall antigens in a large reference population.

The reactivity to five recall antigens, candida, mumps, PPD, varidase and trichophyton and the corresponding diluents was tested in 840 healthy persons aged between 17 and 101 years. Candida antigen was tested in a lower (l) and a higher (h) dose. The size of reactions did not follow a Gaussian distribution and we therefore used the 10th and 5th percentiles instead of standard deviation to define the limits between positive, weak and negative reactions. The number of positive reactions to each of candida-h, mumps, PPD and varidase was between 80 and 95 per cent in patients less than 60 years of age and above this age it varied between 0 and 85 per cent. The number of positive reactions to candida-l and trichophytin was low in all ages. The reactivity was regarded as normal if there was a positive reaction i.e.sum of right angle diameters >10 mm to atl east one antigen, relatively anergic if there was only a weak reaction (7-9 mm) and anergic if there was a negative reaction (0-6 mm) to all antigens. A normal reaction was found in 100 per cent of subjects up to 60 years of age, and in 95 per cent up to 30 years. Among those with normal reactivity, positive results were found with candida-h alone in between 67-93 per cent, candida-h + mumps between 92-100 per cent and candida + mumps + PPD in 100 per cent irrespective of age.

Reserpine and the suppression of both edema formation and cellular infiltrate of the contact sensitivity reaction in the mouse.

Reserpine treatment in doses of 1.0 and 5.0 mg/kg body weight, given 6 h before antigen challenge significantly suppresses the contact sensitivity reaction to picryl chloride in sensitized mice. The suppression involves both the edema formation, measured as ear swelling, and the accumulation of inflammatory cells at the test site. This is probably mediated through inhibition of the release of vasoactive amines from local mast cells.

The cellular infiltrate of the contact sensitivity reaction to picryl chloride in the mouse.

Contact sensitivity to picryl chloride was studied in the mouse ear. The skin hypersensitivity, as a factor of ear swelling, and the intensity of the cellular infiltrate in the skin were evaluated together during the elicitation of the contact sensitivity reaction. It was found that the ear swelling is a mainly vascular reaction preceding the appearance of inflammatory cells. The infiltrating cells in this model of skin sensitivity were differentiated in Giemsa-stained plastic-embedded sections and recorded in a semi-quantitative way. When the cellular reaction was most intense at 48 and 72 hours after challenge, the most numerous inflammatory cells were lymphocytes and eosinophils.

Hypohidrotic ectodermal dysplasia with hypothyroidism.

Two brothers with hypohidrotic ectodermal dysplasia were found to have urticaria pigmentosa-like skin pigmentation with increased mast cells and melanin depositions in the dermis. Structural ciliary abnormalities of the respiratory tract were seen, and these may contribute to their severe recurrent chest infections. Primary hypothyroidism occurred in both by 3 years of age and responded to replacement therapy. The abnormalities seen appear to be the result of a common genetic aberration causing a particular sequence of maldevelopments during embryogenesis. This form of hypohidrotic ectodermal dysplasia associated with hypothyroidism gives a unique insight into the potential extent of structural defects of ectodermal dysplasias.

The cellular infiltrate in experimental allergic and toxic contact dermatitis. Effect of systemically administered corticosteroids.

The effect of systemically administered corticosteroids on allergic and toxic contact dermatitis in the guinea pig was studied. Dermatitis was provoked with dinitrochlorobenzene (DNCB). The influence of corticosteroids on the sensitization phase was also investigated. The epicutaneous test reactions were assessed with the naked eye, low-power microscopy, and a method based on the counting of infiltrating cells in the upper corium. Prednisolone injected in a dose of 5 mg/kg body weight daily for 4 days starting on the 1st day of sensitization or the 1st day of testing tended to shorten the duration of the contract allergic skin reaction as seen with the naked eye. Microscopically, a decrease in the number of infiltrating basophil granulocytes was found. Prednisolone had no convincing influence on the toxic contract eczematous reaction macroscopically or microscopically. Responses to weakly toxic doses of DNCB tended to fade earlier and to show small displacements of granulocytes in the differential count of infiltrating cells compared to controls. The results suggest that prednisolone given systemically influences only slightly the inflammatory cell infiltration in contact dermatitis in the guinea pig.

Lack of association between allergic contact dermatitis and HLA antigens of the A and B series.

A previous study of patients with allergic contact dermatitis yielded results which supported the hypothesis that the presence of certain HLA antigens led to a predisposition to allergen-specific reactions and others to multiple contact sensitivity. The present study was performed to test this hypothesis. 129 patients sensitive to one allergen only (either chromium, nickel, formalin or balsam of Peru) and 83 patients sensitive to two or more allergens were HLA typed regarding the A and B loci. A series of 368 persons matched with regard to sex, age and place of residence were used as controls. A tendency towards an association between HLA B7 and contact allergy was observed. No other data confirming the hypothesis mentioned above were obtained. Among 37 patients who also had atopic diathesis a decreased frequency of HLA B7 was found.

Clinical trial of a potent non-halogenated topical steroid, Budesonide.

In a double-blind, randomized multi-centre study, 116 patients with psoriasis have been treated for 1-3 weeks with budesonide ointment (Preferid, Draco/Tika; a subsidiary of AB ASTRA), a new non-halogenated topical steroid. In a series of 11 patients a 0.025% budesonide ointment was significantly superior to placebo. In a second series, of 54 patients, a 0.025% fluocinolone acetonide ointment (Synalar, ICI). In a third series, of 51 patients, a 0.010% budesonide ointment was compared with 0.025% fluocinolone acetonide ointment. No statistically significant difference between these two preparations was found to exist. No adverse reactions were observed.

Photochemotherapy (PUVA) in the pretumour stage of mycosis fungoides: a report from the Scandinavian Mycosis Fungoides Study Group.

Fifty-one patients with mycosis fungoides of pretumour stage were treated with oral 8-MOP and UVA photochemotherapy (PUVA). Complete remission was induced within 2--3 months in 58% of the cases. Twenty-seven patients are still in remission on maintenance therapy 9--53 months after starting treatment. In 9 cases PUVA treatment was stopped due to therapeutic failure and in another 15 cases due to various side effects. Maintenance therapy was given weekly, monthly, or at even longer intervals. Maintenance at long intervals seems preferable.