Cardiac involvement in hypereosinophilic syndrome.

Hypereosinophilic syndrome is a heterogeneous group of disorders characterised by hypereosinophilia and organ involvement of varying intensity. We describe involvement of the heart in patients with hypereosinophilic syndrome,and the diagnostic and therapeutic clinical management of these patients.

Salade malade: malignant ventricular arrhythmias due to an accidental intoxication with Aconitum napellus.

Intoxication with Aconitum napellus is rare in our regions. Aconite alkaloids can cause ventricular arrhythmia by a prolonged activation of sodium channels. Because the margin of safety is low between the analgesic and toxic dose, intoxication is not rare when Aconite is used in herbal medicine. We present a case in which a 39-year-old male was accidentally intoxicated with Aconite. Even though no antidote or adequate therapy is available he was successfully resuscitated. (Neth Heart J 2008;16:96-9.).

[Total atrioventricular block following a tick bite]. / Totaal atrioventriculair blok na een tekenbeet.

A 40-year-old man was referred to the cardiology outpatient clinic with dizziness, palpitations and shortness of breath. He remembered being bitten by a tick two to three years previously, but had not noticed a characteristic skin rash. The ECG showed a prominent first degree atrioventricular (AV) block and ambulatory electrocardiographic monitoring showed an intermittent complete AV block. A definitive pacemaker was implanted. Antibodies to Borrelia were found. The patient was treated with ceftriaxone. In the weeks and months following implantation, the AV block disappeared completely. The reversibility of the AV block secured the diagnosis 'Lyme carditis with secondary AV block', and the pacemaker was explanted.

Glutathione metabolism in non-ischemic and postischemic rat hearts in response to an exogenous prooxidant.

The objective of the present study was to determine whether mild ischemia hampers the use of tissue concentration of glutathione disulfide (GSSG) and release of GSSG as indices of oxidative stress in postischemic hearts. To this end, the response of the glutathione redox cycle to the prooxidant cumene hydroperoxide (CumOOH) was compared in non-ischemic and postischemic rat hearts perfused in vitro. Perfusion of non-ischemic and postischemic hearts with CumOOH (20-25 microM) for 10 min followed by 20 min of perfusion without CumOOH resulted in similar changes in tissue concentration of GSSG, and similar patterns of GSSG release. The similar response in tissue concentration of GSSG is consistent with the finding that mild ischemia did not affect the formation and reduction of GSSG. While release of GSSG from non-ischemic hearts was solely due to active transport of GSSG, release of GSSG from postischemic hearts was due to both active transport of GSSG and aspecific leakage of GSSG. In conclusion, tissue concentration of GSSG can be reliably used to investigate oxidative stress in postischemic hearts. However, the occurrence of aspecific leakage of GSSG, which is not indicative of oxidative stress, renders release of GSSG from postischemic hearts an unreliable index of oxidative stress.

Myelodysplastic syndrome with vasculitic manifestations.

Vasculitis in patients with the myelodysplastic syndrome (MDS) is a rare phenomenon. We describe a patient who presented with necrotic lesions of his toes, which proved to be the result of immune complex mediated vasculitis. This unusual combination of vasculitis and MDS prompted us to review the literature. Forty-four cases of vasculitis in association with MDS were found. The pathogenesis of the vasculitis in MDS remains speculative, although several reports suggest an immunological mechanism. The temporal relationship could not be determined in 20 (45%) of reported cases. The prognosis of these patients appears to be worse than in patients with MDS without vasculitis. Steroids were used in 41 (93%) of the reported cases. Our patient did not receive any drug therapy, nevertheless his necrotic lesions improved within a few weeks.

Risk of overestimation of free malondialdehyde in perfused rat hearts due to homogenization artifacts.

OBJECTIVES: The aims of the present study were to determine (1) whether free malondialdehyde (MDA) was artifactually formed during homogenization of myocardial tissue and (2) whether free MDA was increased in reperfused rat hearts. METHODS: Groups of isolated buffer-perfused rat hearts were subjected to control perfusion, or 20 min of ischemia, or 20 min of ischemia followed by 5 or 30 min of reperfusion. The hearts were subsequently assayed for free MDA by ion-pairing high-performance liquid chromatography following homogenization in the absence or presence of the antioxidant butylated hydroxytoluene (0.01%). RESULTS: Tissue homogenates prepared in the absence of butylated hydroxytoluene contained significantly higher (P < 0.001) free MDA levels than tissue homogenates from the same hearts prepared in the presence of butylated hydroxytoluene. Free MDA levels of tissue homogenates prepared in the presence of butylated hydroxytoluene were below the detection limit (20 pmol/mg protein) in 27 of 30 tissue homogenates, irrespective of the perfusion protocol. Control experiments showed that the presence of butylated hydroxytoluene did not interfere with the detection of free MDA. CONCLUSIONS: These results indicate that free MDA was formed artifactually during tissue homogenization in the absence of butylated hydroxytoluene. Furthermore, free MDA could not be detected in perfused rat hearts after control perfusion, or 20 min of ischemia, or 20 min of ischemia followed by 5 or 30 min of reperfusion.

Postischemic injury in isolated rat hearts is not aggravated by prior depletion of myocardial glutathione.

The aim of this study was to test the hypothesis that a decreased myocardial concentration of reduced glutathione (GSH) during ischemia renders the myocardium more susceptible to injury by reactive oxygen species generated during early reperfusion. To this end, rats were pretreated with L-buthionine-S,R-sulfoximine (2 mmol/kg), which depleted myocardial GSH by 55%. Isolated buffer-perfused hearts were subjected to 30 min of either hypothermic or normothermic no-flow ischemia followed by reperfusion. Prior depletion of myocardial GSH did not lead to oxidative stress during reperfusion, as myocardial concentration of glutathione disulfide (GSSG) was not increased after 5 and 30 min of reperfusion. In addition, prior depletion of GSH did not exacerbate myocardial enzyme release, nor did it impair the recoveries of tissue ATP, coronary flow rate and left ventricular developed pressure during reperfusion after either hypothermic or normothermic ischemia. Even administration of the prooxidant cumene hydroperoxide (20 microM) to postischemic GSH-depleted hearts during the first 10 min of reperfusion did not aggravate postischemic injury, although this prooxidant load induced oxidative stress, as indicated by an increased myocardial concentration of GSSG. These results do not support the hypothesis that a reduced myocardial concentration of GSH during ischemia increases the susceptibility to injury mediated by reactive oxygen species generated during reperfusion. Apparently, myocardial tissue possesses a large excess of GSH compared to the quantity of reactive oxygen species generated upon reperfusion.

Glutathione disulfide as an index of oxidative stress during postischemic reperfusion in isolated rat hearts.

The objectives of this study were to determine 1) whether reactive oxygen species generated upon postischemic reperfusion lead to oxidative stress in rat hearts, and 2) whether an exogenous prooxidant present in the early phase of reperfusion causes additional injury. Isolated buffer-perfused rat hearts were subjected to 30 min of hypothermic no-flow ischemia followed by 30 min of reperfusion. Increased myocardial content of glutathione disulfide (GSSG) and increased active transport of GSSG were used as indices of oxidative stress. To impose a prooxidant load, cumene hydroperoxide (20 microM) was administered during the first 10 min of reperfusion to a separate group of postischemic hearts. Reperfusion after 30 min of hypothermic ischemia resulted in a recovery of myocardial ATP from 28% at end-ischemia to 50-60%, a release of 5% of total myocardial LDH, and an almost complete recovery of both coronary flow rate and left ventricular developed pressure. After 5 and 30 min of reperfusion, neither myocardial content of GSSG nor active transport of GSSG were increased. These indices were increased, however, if cumene hydroperoxide was administered during early reperfusion. After stopping the administration of cumene hydroperoxide, myocardial GSSG content returned to control values and GSH content increased, indicating an unimpaired glutathione reductase reaction. Despite the induction of oxidative stress, reperfusion with cumene hydroperoxide did not cause additional metabolic, structural, or functional injury when compared to reperfusion without cumene hydroperoxide. We conclude that reactive oxygen species generated upon postischemic reperfusion did not lead to oxidative stress in isolated rat hearts. Moreover, even a superimposed prooxidant load during early reperfusion did not cause additional injury.

Characterization of ultraviolet laser-induced autofluorescence of ceroid deposits and other structures in atherosclerotic plaques as a potential diagnostic for laser angiosurgery.

Unstained frozen sections of normal and atherosclerotic human aorta and coronary artery were examined using histochemical and fluorescence microscopic techniques to identify the structures responsible for autofluorescence under 351 to 364 nm laser excitation. These structures included elastin and collagen in normal and atherosclerotic specimens, calcium deposits in calcified plaques, and granular or ring-shaped deposits histochemically identified as ceroid found in both calcified and non-calcified plaques. Qualitatively, both the color and intensity of ceroid autofluorescence differed greatly from that of elastin or collagen. The emission spectra of elastin, collagen, and ceroid were examined by microscopic spectrofluorimetry, and were found to differ significantly as well. When compared with spectra of elastin and collagen, spectra of ceroid were broader, shifted to the red, and were somewhat resistant to bleaching. We conclude that detection of laser-induced ceroid autofluorescence may aid in identifying plaques for laser ablation.

Circulating buttock cells in non-Hodgkin's lymphoma.

Leukemic B cells with a characteristically sharp nuclear cleft seemingly dividing the nucleus into two or more parts have been entitled "buttock cells" and are subject of this study. These cells were found in leukemic non-Hodgkin's lymphomas (NHL) and usually have been related to follicular center cell lymphomas. However, buttock cells also closely resemble cells present in intermediate lymphocytic lymphoma (ILL) and mantle zone cells of reactive lymphoid tissues. Ultrastructurally, it became apparent that the separate nuclear lobes of buttock cells were connected by chromatin bridges. Immunophenotypically, circulating buttock cells had a variable phenotype, which may indicate either a follicle center or mantle zone origin. The use of CD5 and FMC7 monoclonal antibodies might be of discriminative help. These leukemic NHL have to be differentiated from classical chronic lymphocytic leukemia (CLL) with help of cytomorphology and immunophenotyping, since the former usually have a worse prognosis and generally will require a different treatment.