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Human semilunar donor heart valves can be stored in banks, awaiting transplantation. To evaluate the result of the preservation protocols, a quantitative description of the tissue is necessary. In this study we investigated in a quantitative way the contractile properties of fresh and cryopreserved porcine isolated aortic heart valve leaflets in response to a number of endogenous vasoactive compounds. The responses of strips of the aortic wall were included for comparison. Contraction was measured isometrically in response to potassium (K+; 100 mmol/L), 5-hydroxytryptamine (1 nmol/L to 100 micromol/L), noradrenaline (1 nmol/L to 100 micromol/L), endothelin-1 (0.01 nmol/L to 0.3 micromol/L), and prostaglandin F(2alpha) (0.1 nmol/L to 10 micromol/L). The pharmacologic parameters E(MAX) (the maximal response expressed as a percentage of contraction to a 100 mmol/L dose of K+) and EC50 (the concentration that produces 50% of the maximal effect) were calculated for every compound (n = 6 to 7 each). We observed that all specimens contracted in response to potassium. Its magnitude in fresh leaflets equaled 1.6 +/- 0.14 mN compared with 26.6 +/- 2.6 mN in fresh aortic wall. Noradrenaline, endothelin-1, and prostaglandin F(2alpha) all caused contraction in valvular leaflets and aortic wall, whereas 5-hydroxytryptamine caused contraction in the valvular leaflets but relaxation in aortic wall. After cryopreservation, the response to K+ amounted to 24% of the response of the fresh specimens in valvular leaflets (n = 25) and 14% in aortic wall (n = 26). The values of E(MAX) and EC50 of the responses to noradrenaline, endothelin-1, and prostaglandin F(2alpha) remained unchanged. Although the physiologic relevance of contraction of valvular leaflets needs further study, its measurement may provide an additional model to verify the consequences of alternative methods of preservation.

A patient with an aorticopulmonary paraganglioma was found to have normal plasma norepinephrine and epinephrine levels and elevated dopamine levels. Iodine-123-MIBG scintigraphy did not visualize this tumor. The same finding on a negative MIBG scan in two patients with exclusively dopamine-secreting chemodectomas has been previously reported. In our patient, [111In-DTPA-D-Phe1]-octreotide scintigraphy proved to be an effective imaging technique.

Objective: To study the localisation of treponemes and to analyse the inflammatory infiltrate in biopsy specimens from patients with primary or secondary syphilis, or early infectious yaws., Materials and Methods: Skin biopsies originating from human lesions of primary (29x) or secondary (15x) syphilis (Rotterdam), or early yaws (18x) (West Sumatra) were studied. Different histochemical and immunohistochemical detection methods were used in this study., Results and Conclusion: The histochemical silver staining method according to Steiner revealed the presence of T. pallidum in all cases of primary syphilis studied. In 10 out of 14 cases of secondary syphilis, treponemes were demonstrated. With an immunofluorescence staining technique (IF) using anti-T. pallidum antiserum raised in rabbits (a-Tp), T. pallidum was demonstrated in 28 out of 29 cases of primary syphilis, and in 14 out of 14 studied cases of secondary syphilis. The silver staining method and IF showed identical localisations of T. pallidum (mainly in the dermal-epidermal junction zone or throughout the dermis). Using a-Tp antiserum in the indirect immunofluorescence technique, T. pertenue could be demonstrated in the dermis more often than with Steiner silver staining. However, epidermotropism of T. pertenue in yaws specimens was remarkable, compared with more mesodermotropism of T. pallidum; numbers of T. pertenue in the dermis were limited in all specimens. The dermal inflammatory infiltrate in primary and secondary syphilis was composed mainly of lymphocytes and plasma cells. In most cases more T (CD3 positive) cells than B (CD22 positive) cells were present. Regarding T cell subpopulations, in primary syphilis, T helper/inducer (CD4 positive) cells predominated in 86% of cases. In secondary syphilitic lesions, numbers of T helper/inducer cells were less frequent than or equal to T-suppressor/cytotoxic (CD8 positive) cells in 60% of cases. Remarkably, in yaws specimens the inflammatory infiltrate consisted mainly of IgG, but also IgA and IgM producing plasma cells. T or B lymphocytes were scarce, which is in sharp contrast with findings in syphilitic lesions.

Objectives: The safety and long-term results of directional coronary atherectomy in stented coronary arteries were determined. In addition, tissue studies were performed to characterize the development of restenosis., Methods: Directional coronary atherectomy was performed in restenosed stents in nine patients (10 procedures) 82 to 1,179 days after stenting. The tissue was assessed for histologic features of restenosis, smooth muscle cell phenotype, markers of cell proliferation and cell density. A control (no stenting) group consisted of 13 patients treated with directional coronary atherectomy for restenosis 14 to 597 days after coronary angioplasty, directional coronary atherectomy or laser intervention., Results: Directional coronary atherectomy procedures within the stent were technically successful with results similar to those of the initial stenting procedure (2.31 +/- 0.38 vs. 2.44 +/- 0.35 mm). Of five patients with angiographic follow-up, three had restenosis requiring reintervention (surgery in two and repeat atherectomy followed by laser angioplasty in one). Intimal hyperplasia was identified in 80% of specimens after stenting and in 77% after coronary angioplasty or atherectomy. In three patients with stenting, 70% to 76% of the intimal cells showed morphologic features of a contractile phenotype by electron microscopy 47 to 185 days after coronary intervention. Evidence of ongoing proliferation (proliferating cell nuclear antigen antibody studies) was absent in all specimens studied. Although wide individual variability was present in the maximal cell density of the intimal hyperplasia, there was a trend toward a reduction in cell density over time., Conclusions: Although atherectomy is feasible for the treatment of restenosis in stented coronary arteries and initial results are excellent, recurrence of restenosis is common. Intimal hyperplasia is a nonspecific response to injury regardless of the device used and accounts for about 80% of cases of restenosis. Smooth muscle cell proliferation and phenotypic modulation toward a contractile phenotype are early events and largely completed by the time of clinical presentation of restenosis. Restenotic lesions may be predominantly cellular, matrix or a combination at a particular time after a coronary procedure.

In two unusual cases of pemphigus, classified as pemphigus erythematosus (PE), the clinical and laboratory data are summarized and discussed. In case I, with characteristic immunologic features of PE, acantholysis was detectable only by the EM-technique. Case II with transitory pemphigus and features of SLE was diagnosed as "probable PE". In this case (case II) concomitant incidence was found of benign thymoma. In addition in both cases the patterns of T-cells and T-cell-subsets in blood and lesional skin are briefly discussed.

Linear IgA disease (granular type) associated with chronic active hepatitis in a sixteen-year-old male patient is described. The diagnosis was established by clinical and histopathological findings supported by immunofluorescence studies. The immunofluorescence pattern (granular IgA deposits along the basement membrane, more pronounced at tips of papillae) showed much transition in dermatitis herpetiformis and also to a lesser extent in pemphigoid (linear IgG and IgM deposits along the basement membrane). Chronic active hepatitis as linear IgA disease are significantly correlated with HLA B8. This is the first report of the association of linear IgA disease and chronic active hepatitis.

This report deals with the reaction pattern(s) of two monoclonal antibodies (MoAbs) with normal skin and basal cell carcinomas (BCC). Using indirect immunoperoxidase (IIP) and indirect immunofluorescence (IIF) techniques, MoAb 12 G7 was observed to react with a determinant related to the cell membrane of the epidermal basal cells. In the IIP technique MoAb 12 G7 showed a positive reaction with 32 out of 34 BCC (94%), while in IIF all the 14 BCC that were studied were positive. In most cases only the cells at the periphery of the tumour nests were stained. MoAb 253 B7 reacted with cytoplasmic determinant(s) of the epidermal basal cells both in the IIF as well as in the IIP techniques. Using the IIP technique only 5 out of 34 BCC (15%) showed a positive reaction with this MoAb. Four of the 5 positively staining tumours showed aggressive histological features. Using IIF technique only 2 out of 14 BCC were positive. The results presented in this communication are discussed with regard to the possible expression of selective differentiation and tumor-associated determinant(s) in BCC.

We investigated the peritumoral inflammatory infiltrate in 22 basal cell carcinoma (BCC) from 18 patients using a series of monoclonal antibodies. In all the 22 BCC the infiltrate consisted mainly of T cells (55 +/- 15%) and only in three cases an invasion of the tumor nests by these cells was observed. The T helper (TH) subset predominated over the T suppressor/cytotoxic (TS/C) subset (TH/TS/C ratio of 1.9 +/- 0.8). In 8 of 22 BCC mild infiltrate was observed with 48 +/- 13% T cells and a TH/TS/C ratio of 1.5 +/- 0.6. In 14 of 22 BCC moderate to heavy infiltrate with 59 +/- 15% T cells and a TH/TS/C ratio of 2.0 +/- 1.0 was observed. There was a significant difference in the percentage of T cells in BCC with moderate to heavy infiltrate and that in BCC with mild infiltration. The mean percentage of HLA-DR+ cells was 54 +/- 11%; Langerhans cells (LC) 4 +/- 5%; and Leu-M5+ (monocytes and macrophages) 16 +/- 11%. Less than 2% Leu-14+(B) cells were seen in the infiltrate. The mean percentage of Leu-7+ (natural killer) cells was 4 +/- 4%, and only 1 of 22 BCC Leu-7+ cells invaded tumor nests, contacting with tumor cells. From these results we concluded that T cells play a major role in the defence against BCC proliferation. The main role of Langerhans cells and Leu-M5+ cells may be that of antigen presentation. B cells and NK cells probably play a minor role in the local defence against BCC proliferation.

Two new cases of the rare, nonmucosal and nonscarring localized variety of pemphigoid are described. With reference to the data in the recent literature, the disease was classified as Localized Bullous Pemphigoid (LBP). The ultrastructural and immunologic findings are described and are briefly discussed in the context of the possible mechanisms leading to local subepidermal tissue injury in LBP. Although classical features of humoral responsiveness (in vivo bound IgG and complement at the epidermal basal membrane-zone (BM-zone)) were observed, a possible additional role of T cell mediated immunity in generating this local disease is considered.