Prediction,identification and progression of histopathological liver disease activity in children with intestinal failure

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IgE Reactivity of the Dog Lipocalin Allergen Can f 4 and the Development of a Sandwich ELISA for Its Quantification

Purpose

Divergent results on the IgE reactivity of dog-allergic subjects to Can f 4 have been reported. The aim of this study was to evaluate the significance of Can f 4 in dog allergy and to develop an immunochemical method for measuring Can f 4 content in environmental samples.

Methods

We purified the natural dog allergen Can f 4 from a dog dander extract by monoclonal antibody-based affinity chromatography and generated its variant in a recombinant form. Sixty-three dog-allergic patients and 12 nonallergic control subjects were recruited in the study. The IgE-binding capacity of natural Can f 4 and its recombinant variant was assessed by ELISA, immunoblotting, and skin prick tests (SPT).

Results

Eighty-one percent of the dog-allergic patients showed a positive result to the immunoaffinity-purified natural Can f 4 in IgE ELISA, but only 46% in IgE immunoblotting. Respective results with the recombinant Can f 4 variant were 54% and 49%. SPT results reflected those obtained in ELISA and immunoblotting. The overall IgE reactivity of the immunoaffinity-purified natural Can f 4 was found to depend strongly on the integrity of the allergen''s conformation. A sandwich ELISA based on monoclonal antibodies was found to be functional for measuring Can f 4 in environmental samples.

Conclusions

Can f 4 is a major allergen of dog together with Can f 1 and Can f 5. In combination with other dog allergens, it improves the reliability of allergy tests in dog allergy.     

Cardiac troponin in ischemic cardiomyocytes: Intracellular decrease before onset of cell death

Aim

Cardiac troponin I (cTnI) and T (cTnT) are the most important biomarkers in the diagnosis of acute myocardial infarction (AMI). Nevertheless, they can be elevated in the absence of AMI. It is unclear if such elevations represent irreversible cardiomyocyte-damage or leakage from viable cardiomyocytes. Our objective is to evaluate whether cTn is released from viable cardiomyocytes in response to ischemia and to identify differences in the release of cTn and its molecular forms.

Methods and results

HL-1 cardiomyocytes (mouse) were subjected to ischemia (modeled by anoxia with glucose deprivation). The total contents and molecular forms of cTn were determined in culture media and cell lysates. Cell viability was assessed from the release of lactate dehydrogenase (LDH). Before the release of LDH, the intracellular cTn content in ischemic cells decreased significantly compared to control (52% for cTnI; 23% for cTnT) and was not matched by a cTn increase in the medium. cTnI decreased more rapidly than cTnT, resulting in an intracellular cTnT/cTnI ratio of 25.5 after 24 h of ischemia. Western blots revealed changes in the relative amounts of fragmented cTnI and cTnT in ischemic cells.

Conclusions

HL-1 cardiomyocytes subjected to simulated ischemia released cTnI and cTnT only in combination with the release of LDH. We find no evidence of cTn release from viable cardiomyocytes, but did observe a significant decrease in cTn content, before the onset of cell death. Intracellular decrease of cTn in viable cardiomyocytes can have important consequences for the interpretation of cTn values in clinical practice.     

Human monoclonal Fab and human plasma antibodies to carbamyl‐epitopes cross‐react with malondialdehyde‐adducts

Oxidized low‐density lipoprotein (OxLDL) plays a crucial role in the development of atherosclerosis. Carbamylated LDL has been suggested to promote atherogenesis in patients with chronic kidney disease. Here we observed that plasma IgG and IgM antibodies to carbamylated epitopes were associated with IgG and IgM antibodies to oxidation‐specific epitopes (ρ = 0·65–0·86, P < 0·001) in healthy adults, suggesting a cross‐reaction between antibodies recognizing carbamyl‐epitopes and malondialdehyde (MDA)/malondialdehyde acetaldehyde (MAA) ‐adducts. We used a phage display technique to clone a human Fab antibody that bound to carbamylated LDL and other carbamylated proteins. Anti‐carbamyl‐Fab (Fab106) cross‐reacted with oxidation‐specific epitopes, especially with MDA‐LDL and MAA‐LDL. We showed that Fab106 bound to apoptotic Jurkat cells known to contain these oxidation‐specific epitopes, and the binding was competed with soluble carbamylated and MDA‐/MAA‐modified LDL and BSA. In addition, Fab106 was able to block the uptake of carbamyl‐LDL and MDA‐LDL by macrophages and stained mouse atherosclerotic lesions. The observed cross‐reaction between carbamylated and MDA‐/MAA‐modified LDL and its contribution to enhanced atherogenesis in uraemic patients require further investigation.     

Systematic review of medical therapy to prevent recurrent diverticulitis

Aim and background

One of today’s controversies remains the prevention of recurrent diverticulitis. Current guidelines advise a conservative approach, based on studies showing low recurrence rates and a high operative morbidity and mortality. Conservative measures in prevention recurrence are dietary advises and medical therapies, including probiotics and 5-aminosalicylic acid.

Objectives

The aim of this systematic review is to assess whether medical or dietary therapies can prevent recurrent diverticulitis after a primary episode of acute diverticulitis.

Method and search strategy

We searched different databases for papers published between January 1966 and January 2011.

Study selection

Clinical studies were eligible for inclusion if they assessed the prevention of recurrent diverticulitis with a medical or dietary therapy. Exclusion criteria were studies without a control group.

Results

Three randomized controlled trials (RCT), all with a Jadad quality score of 2 out of 5, were included in this systematic review. Mesalazine results in significantly less disease recurrence and fewer symptoms after an acute episode. The use of probiotics decreases symptoms but does not reduce recurrence. No difference in effect is seen when Balsalazide is added to probiotics compared to probiotics only. No relevant studies on dietary therapy/advices or antibiotics for prevention of recurrent diverticulitis were found.

Conclusion

The evidence that supports medical therapy to prevent recurrent diverticulitis is of poor quality. Treatment with 5-aminosalicylic acid seems promising. Based on current data, no recommendation of any non-operative relapse prevention therapy for diverticular disease can be made.     

Associations between inflammatory markers, candidate polymorphisms and physical performance in older Danish twins

Inflammation may play an essential role in the decline of physical performance. In this study we investigated the associations between inflammatory markers, candidate polymorphisms and physical performance in elderly people. Plasma levels of TNF-α, IL-6, CRP, fibrinogen, sICAM-1 and candidate polymorphisms were measured in 600 twin individuals aged 73 years and older participating in the Longitudinal Study of Aging Danish Twins. Physical performance was assessed using a self-reported measure. The inclusion of twins allowed both traditional and within-twin-pair analysis which permitted control for shared environment and genetic factors. Higher levels of inflammatory markers were generally associated with a lower level of physical performance. The TNFα-238G/A polymorphism was significantly associated with physical performance in men, with A allele carriers having significantly better performance than GG homozygotes. However, this gene variation seems to have only a minor role in explaining the associations between the levels of inflammatory markers and physical performance. When using twin pair analysis to test whether genetic factors in general account for this association, results showed that the association between the level of fibrinogen and physical performance could be caused by genetic factors. Also the association between the level of TNF-α and physical performance in males could be caused by genetic factors. However, other gene variations than the candidate gene polymorphisms studied here seem to explain the major part of the genetic proportion of this association.     

The Effect of Stimulus Parameters on TMS–EEG Muscle Artifacts

BackgroundWhen transcranial magnetic stimulation (TMS) is delivered close to the lateral aspects of the head, large-amplitude (～10–1000 μV) biphasic electroencephalographic (EEG) deflections, peaking at around 4–10 and 8–20 ms, appear.ObjectiveTo characterize the spatiotemporal features of these artifacts, to quantify the effect of stimulus parameters on them, and thus, to study the feasibility of different measurement procedures to decrease the artifacts online. Furthermore, to show that these deflections, when measured with a sample-and-hold system, mainly result from excitation of cranial muscles.MethodsThree subjects received TMS to 16 sites over the left hemisphere. TMS-compatible EEG was recorded simultaneously. Four other subjects received TMS to M1 with different coil rotation and tilt angles and stimulation intensities. We also stimulated a conductive phantom and recorded simultaneous EEG to exclude the possibility of residual electromagnetic artifacts.ResultsThe artifacts were largest when the stimulator was placed above cranial muscles, whereas stimulation of relatively central sites far from the muscles produced muscle artifact-free data. The laterally situated EEG channels were most severely contaminated. The artifacts were significantly reduced when reducing the intensity or when tilting or rotating the coil so that coil wings moved further away from the temporal muscle, while brain responses remained visible. Stimulation of the phantom did not produce such large-amplitude biphasic artifacts.ConclusionAltering the stimulation parameters can reduce the described artifact, while brain responses can still be recorded. The early, laterally appearing, large biphasic TMS-evoked EEG deflections recorded with a sample-and-hold system are caused by cranial muscle activation.