Objective: Circulating proteins linked to atherosclerosis may improve cardiovascular (CV) disease prediction. Here, we applied proteomic profiling, feature selection and unbiased clustering to identify proteins associated with carotid atherosclerosis and integrate them in a protein-based classification system for prediction of future CV events. Design and method: 491 community-dwelling participants (mean age, 58±11 years; 51% women) underwent carotid ultrasonography and proteomic profiling (CVD II panel, Olink Proteomics) at baseline. Subsequently, we collected cardiovascular outcome for a median follow-up period of 10.2 years. We applied partial least squares (PLS) and a machine learning algorithm (Random Forest, RF) to identify proteins associated with carotid intima-media thickness (cIMT) and the presence of atherosclerotic plaques. Next, we assessed the association of future CV events with protein-based phenogroups defined by unbiased clustering (Gaussian Mixture modelling) based on influential proteins in PLS and RF. Results: Of 92 measured proteins, 13 were labelled as important by PLS and RF and were independently associated with cIMT and/or the presence of plaques after multivariable adjustment: pro-adrenomedullin, agouti-related protein, brother of CDO, CD40 ligand, CD84, GLO1, HB-EGF, HSP27, lipoprotein lipase, lymphotactin, PAR-1, PDGF subunit B and TGM2. Based on these proteins, the clustering algorithm subdivided the cohort into two distinct phenogroups. Compared to the first (n = 174), participants in the second phenogroup (n = 317) had: i) a more unfavourable lipid profile with higher total cholesterol and triglycerides and lower HDL cholesterol (P<0.014 for all), but no differences in other CV risk factors such as age, blood pressure, smoking status and diabetes mellitus (P>0.061 for all); ii) higher cIMT (P = 0.0020); and iii) a significantly higher risk for future CV events during follow-up (multivariable-adjusted hazard ratio (95% CI) versus cluster 1: 2.63 (1.25 to 5.56); P = 0.01). Conclusions: Carotid atherosclerosis was linked to proteins reflecting haemostasis, angiogenesis, blood pressure regulation and inflammation. Focused proteomic phenomapping adequately identified individuals at high risk for future CV events and may thus complement current CV risk stratification strategies.

The retraction of dog platelet-rich plasma (PRP) clotted with Reptilase in the presence of inducers and inhibitors of the platelet adhesion-aggregation reaction was studied. In contrast to human cells, dog platelets fail to support retraction in an ADP-Reptilase system. With Thrombofax as aggregation inducer, slight (without additional CaCl2-MgCl2) to moderate (with additional CaCl2-MgCl2) retraction occurs. In contrast to human samples, such retraction is inhibited by platelet release inhibitors. Electron-microscopic examinations show that Thrombofax, but not ADP, induces the formation of large cytoplasmic protrusions from dog platelets. Such formation is inhibited by release-inhibitors. The results of the study support the concept that platelet pseudopod formation, rather than the release reaction, is a prerequisite for clot retraction.

Although insufficient milk production in lactating sows may cause tremendous economic losses, reliable methods for estimating milk production in sows under field conditions are not available. This study aimed to investigate whether urine parameters could be used to predict milk production in sows. The milk production of 18 sows was determined during early and mid-lactation. Morning (a.m.) and afternoon (p.m.) urinary levels of potassium (K), sodium (Na), calcium (Ca), magnesium (Mg), lactose and creatinine were analysed. The absolute concentrations, the ratios relative to creatinine, and the fractional excretions of all elements in urine were not significantly associated with milk production. The p.m./a.m. ratios of K, Na and Ca concentrations in urine (K(R), Na(R), and Ca(R)) were significant predictors for milk production, but only during mid-lactation. The total variation in milk production (r(2) value) explained by K(R), Na(R), Ca(R) amounted to 72%, 55%, 42%, respectively. Analysis of minerals and especially K in the a.m. and p.m. urine of sows during mid-lactation provided an acceptable indication of milk production. Further research is necessary to investigate whether the present results can be used to estimate milk production in hypogalactic sows under field conditions.

Abstract In the Eocene to Oligocene transitional strata in Belgium, clay mineral associations vary in response to the climatic evolution and to tectonic pulses. Decreasing smectite to illite ratios and the systematic occurrence of illite-smectite irregular interlayers are consequences of a cooling climate. A marked increase in kaolinite content occurs just after a major unconformity formed at the Bartonian/Priabonian boundary and consequently is interpreted as resulting from the breakdown of uplifted saprolites.

The entity 'benign summer light eruption' (BSLE) has been introduced to make a clinical subdivision in the heterogeneous group of polymorphous light eruptions (PLE). Provocation tests for PLE are not always easy to perform and require expensive apparatus. Our purpose was to evaluate a provocation test that could be readily done by a dermatologist with a UVA cabin. Provocation tests are currently required in order to obtain a financial contribution from the social security services in Belgium. In addition, we were interested in determining whether the results of the provocation test would permit us to differentiate between the clinical entities of BSLE and PLE. We studied the efficacy of whole-body UVA irradiation for BSLE and PLE patients. A total of 45 patients was tested, of whom 26 were diagnosed as having BSLE and 19 PLE. In the BSLE group, 24 patients (92%) presented lesions. In the PLE group, 15 patients (79%) had a reaction, but 3 had a positive UVB test. The mean dose to induce lesions was 65.96 J/cm2 for the BSLE group and 52.86 J/cm2 for the PLE group. We conclude that the whole-body UVA test is a high-performance provocation test for both BSLE and PLE patients although it cannot differentiate the two entities from one another.

Polymorphic light eruption (PLE) lesions were induced in 26 patients after an average of 60 J total body UVA irradiation. Using the criteria of the French literature, that make a distinction between PLE and benign summer light eruption (BSLE), the group of 26 patients with PLE was divided into 12 patients with BSLE and 14 patients with PLE, on the basis of historical criteria. Biopsies were taken and compared immunohistochemically with biopsies from 15 unirradiated normal control subjects, in order to find evidence in support of the hypothesis that PLE involves a delayed-type hypersensitivity reaction. The provoked lesions showed: ICAM-1 expression on the keratinocytes of the basal and suprabasal cell layers in 18 of 25 patients, i.e. 72%; HLA-DR expression on the keratinocytes of the basal, squamous and granular cell layer in 13 of 25 patients, i.e. 52%; and OKM5 expression on the keratinocytes of the granular cell layer in 13 of 26 patients, i.e. 50% of the cases. The control samples showed no such antigen expression on the keratinocytes, except for two cases where weak and very localized ICAM-1 positivity was observed; one of these also had a slight localized positivity for HLA-DR and OKM5. The results of the phototesting procedures and the immunohistochemical investigations were similar in both BSLE and PLE. This suggests that they are the same condition, and the term BSLE should therefore probably be discarded. The results of our investigations support the theory of an immunological basis for PLE.

ABSTRACTThe cyclic related growth and regression of the corpus luteum during four consecutive oestrous cycles of the regular four‐day‐cycling (ie, 16 days), virgin albino Wistar rat were followed up by light and electron microscopic investigation of the ovaries. After ovulation, follicular granulosa cells differentiated into luteal cells in the newly formed corpus luteum. Based on their specific histological characteristics, four various types of corpus luteum in each stage of the oestrous cycle could be identified. As soon as the luteal cells started to degenerate, the number of fibroblasts progressively increased and apoptotic degeneration of luteal cells was initiated and became most prominent during oestrus. Complete regression of the corpus luteum was seen after 15 days. This study shows a strictly organised pattern of luteal cell growth and degeneration in the corpus luteum of the regular four‐day‐cycling, virgin Wistar rat. The morphological alterations may be regulated by a hormonal fluctuation.

In the present study an animal model is described in which a sustained non-specific airway hyperresponsiveness is induced. Guinea pigs were inoculated intratracheally with parainfluenza type 3 (PI-3) virus or control solution. Two, 4, 8, and 16 days after inoculation the tracheae, bronchi, and lung strips were isolated and mounted in organ baths. Two days after inoculation no difference between the control solution and PI-3 virus group was observed, with respect to the histamine concentration/response curve obtained from tracheae, bronchi and lung strips of the respective groups. However, histamine concentration/response curves were significantly (P < 0.01) shifted upwards in all parts of the airways 4, 8, and 16 days after PI-3 inoculation as compared with the control solution. The excessive contraction of the trachea was not specific for histamine, since an increase in the maximal response was obtained also for the cholinergic receptor agonist, arecoline on day 4 (32%, P < 0.05), day 8 (24%, P < 0.05), and day 16 (28%). Morphological examination of the central airways obtained from control solution-inoculated animals revealed no signs of inflammation. However, 2, 4, and 8 days, but not 16 days, after the viral infection, epithelial damage with loss of cilia and mucus-depleted goblet cells were observed. Thus, morphological changes were not directly associated with changes in airways responsiveness. Histological examination of the peripheral airways revealed an influx of inflammatory cells, as shown by typical lesions of patchy alveolitis and bronchiolitis. Bronchiolar epithelium was variously hyperplastic and dysplastic with degenerative changes, and the lumens of the bronchioli were occluded with mucus and inflammatory cells. In conclusion, the virus-induced airway hyperresponsiveness in guinea pigs shows similarities with the human situation, in which a sustained non-specific airway hyperresponsiveness is observed after a respiratory viral infection. In addition, the hyperresponsiveness seems to be accompanied by an influx of inflammatory cells in the airways but not with other morphological changes.

The effect of ridogrel, a combined thromboxane A2 synthase inhibitor/prostaglandin endoperoxide receptor antagonist, on the lysis of platelet-rich thrombi with recombinant tissue-type plasminogen activator (rt-PA) was studied in everted (inside-out) femoral arterial grafts inserted in the left anterior descending coronary arteries of heparinised dogs. Thrombotic occlusion of the everted segment graft with a platelet-rich thrombus, persisting for at least 30 min, occurred spontaneously within 4.3±3.9 min (mean±SD). These dogs were then heparinised and randomised to 1 of 4 blinded treatment groups: double placebo infusion, bolus injections of 0.5 mg/kg rt-PA, repeated at 15 min intervals until recanalisation occurred or up to 4 doses, ridogrel infusion (5 mg/kg bolus followed by continuous infusion of 5 mg/kg over 150 min), or the combination of rt-PA and ridogrel. In the control group, stable occlusion as measured with an electromagnetic flow probe was maintained throughout the observation period. rt-PA produced reperfusion in 3 of 5 dogs, associated with cyclic reocclusion and reflow in 1 dog. Ridogrel administration did not produce recanalisation in any of the animals. The combined administration of ridogrel and rt-PA produced stable reperfusion without reocclusion in all of 5 dogs (p<0.003 vs control groups), within 41±17 min. Coronary blood flow after recanalisation was significantly higher (p<0.05) in dogs given rt-PA and ridogrel (29±6 ml/min after 10 min and 30±9 ml/min after 60 min) than in dogs given rt-PA alone (10±5 ml/min after 10 min and 14±6 ml/min after 60 min). Ridogrel, alone or in combination with rt-PA, prolonged the template bleeding time from approximately 3.5 min to more than 20 min, whereas rt-PA alone did not significantly affect the bleeding time. The results indicate that ridogrel enhances and sustains recanalisation of platelet-rich arterial thrombosis with rt-PA.

For the investigation of whether inflammatory cells were responsible for virus-induced airway hyperresponsiveness, tracheal spirals from healthy guinea pigs were incubated in organ baths with different numbers of bronchoalveolar cells obtained from guinea pigs 4 days after their inoculation with parainfluenza-3 (P-3) virus or control solution. Airway responsiveness was measured by performance of histamine concentration/response (C/R) curves on the Preparations incubated with 5 x 10(5) cells/ml obtained from guinea pigs treated with P-3 virus demonstrated a significant upward shift of the histamine C/R curve. The maximal contraction was increased by 26% as compared with the tissues incubated with the same number of cells from animals inoculated with control solution. When the number of cells was increased further to 5 x 10(6) cells/ml, no additional upward shift of the C/R curve was seen; the increase in maximal contraction was 24%. Tracheal spirals incubated with 5 x 10(4) cells/ml did not affect the histamine C/R curves. Addition of P-3 virus to the organ bath during the incubation period with the cells did not affect the histamine C/R curve either, irrespective of the inoculation solution or the number of bronchoalveolar cells used. The relative number of alveolar macrophages in bronchoalveolar lavage fluid decreased significantly from 86.3% +/- 2.6% in the control group to 71.8% +/- 3.3% in the P-3 virus group as a consequence of a significant increase in the percentage of monocytes, lymphocytes, and eosinophils. These results suggest that bronchoalveolar cells are causally involved in the virus-induced airway hyperresponsiveness.

A buffered solution was perfused at a constant flow rate (2 ml/min) through both iliac arteries in rat hindquarters. Perfusion pressures were measured in normal and collateralized vascular beds of the left and right hind-leg, respectively. Bolus injections of various agonists produced concentration-dependent increases in perfusion pressure in both collateralized and normal circulatory beds. Serotonin, in particular, and noradrenaline, to a lesser extent, produced more pronounced vasoconstriction on the collateral side than on the normal side. The difference in vasoreactivity to serotonin was related to a difference in both vascular structure and sensitivity of both types of vascular bed. Vasoconstriction induced by serotonin was inhibited by 5-HT2 antagonists. Selective blockade of alpha 1,alpha 2,beta 1-beta 2 adrenoceptors and amine uptake blockade were ineffective. This study indicates that, in rat hind-legs, the collateralized vascular bed is superreactive to serotonin in comparison with the normal bed. This resetting of reactivity to serotonin is due to the specific vascular structure as well as to an increased 5-HT2 receptor-mediated sensitivity.

Both lupus anticoagulant and anticardiolipin antibody are groups of antiphospholipid antibodies associated with high frequency of thrombosis, fetal loss and thrombocytopenia. The hall marks of their identification is the prolongation of phospholipid-dependant coagulation tests. Much is written in literature about the successful management of lupus anticoagulant during pregnancy, via corticosteroid and acetyl salicylic acid (Aspirin) therapy; however, up to now only little has been mentioned about maternal and fetal complications associating lupus anticoagulant and its management. Here we present three cases with significant complications among patients with lupus anticoagulant managed in Sint Augustinus Hospital over the last 3 years. These complications were secondary to antiphospholipid syndrome or to therapy. Maternal complications included gastritis, atrophy of quadriceps muscle, resistant premature contractions and pre-eclampsia. One of our patients developed small lymphocytic lymphoma 1 year after her last labour. Fetal complications included: prematurity, suprarenal insufficiency (temporary) and delayed neuromuscular development found at the 2 year follow-up. As far as we know, some of these complications have never been mentioned in literature.