P1358 New insights into cardiac dysfunction assessed by left atrial function in patients with type 1 diabetes mellitus

BACKGROUND

There have been many reports of heart failure due to diabetic cardiomyopathy and decreased left ventricular (LV) function with increasing age in patients with type 1 diabetes mellitus (T1DM). Recently, although left atrial (LA) function has been occasionally reported to be a more useful prognostic indicator than LV function in acquired heart diseases, LA function in patients with T1DM has not yet been studied.

PURPOSE

To investigate LA dysfunction in patients with T1DM.

METHODS

Fifty patients with T1DM were recruited (age, 5–41 years). We excluded patients who had a history of heart disease, hypertension, and those taking cardioprotective agents. The patients and 50 age-matched controls were classified into 3 age groups (D1, C1, 5–14 years; D2, C2, 15–29 years; D3, C3, 30–41 years). The LA phasic function serving as the reservoir, conduit, and pump strains; the LA strain rate (SR) in the systole, early diastole, and late diastole; and the LV global longitudinal strain (LV-LS) as determined via 2-dimensional speckle tracking imaging were measured from the apical four- and two-chamber views. We also calculated the LA stiffness index as the ratio of E/e’ to the LA reservoir strain.

RESULTS

There was no significant difference in left ventricular ejection fraction in each age group. The LA reservoir strains in D2 and D3 were significantly lower than those in C2 (40.8 ± 5.7% vs. 47.2 ± 5.5%, p = 0.005) and C3 (39.2 ± 5.5% vs. 47.3 ± 5.7%, p = 0.004), respectively. The LA conduit strain in D2 was significantly lower than that in C2 (28.9 ± 5.8% vs. 35.0 ± 5.0%, p = 0.006). The LA pump strain and the three phases of LA SR were not significantly different among the age groups. The LA stiffness index in D3 increased significantly compared to that in N3 (0.18 ± 0.05 vs. 0.13 ± 0.01, p <0.001). The LV-LS in D2 and D3 was significantly lower than that in C2 (-15.7 ± 1.7% vs. -18.7 ± 2.1%, p <0.001) and C3 (-15.3 ± 1.8% vs. -19.3 ± 2.0%, p <0.001), respectively. The LA reservoir strain significantly correlated with LV-LS (r = -0.468, p < 0.001). Both the LA reservoir strain and LV-LS in patients with T1DM decreased significantly (p = 0.028, p < 0.042, respectively) and correlated with increasing age (r = -0.323, r = 0.286, respectively). The LV stiffness index did not correlate with age or LV-LS.

CONCLUSIONS

The LA reservoir strain might be as useful as LV-LS as an early marker of cardiac dysfunction in patients with T1DM. The correlation coefficient between the LA reservoir strain and LV-LS was not strong. Therefore, although LV-LS might affect the LA reservoir strain, it might represent other aspects of cardiac dysfunction. The increase of LA stiffness might represent the changes in LA wall properties and could be another useful indicator of cardiac dysfunction during long-term follow-ups, which is independent of LV-LS. Overall, these findings provide new insights into cardiac dysfunction in patients with T1DM.

Cytokines in the gastric mucosa of children with Helicobacter pylori infection

AIM

Few studies have looked at the cytokine profile in gastric mucosa in children with Helicobacter pylori infection. This study investigated cytokines and their effects on histological abnormalities in the gastric mucosa of children with H. pylori infection.

METHODS

The levels of interferon-gamma (IFN-gamma), interleukin-4 (IL-4) and IL-8 proteins were measured in biopsy specimens from the gastric antrum and corpus of children with H. pylori infection, and related to inflammatory cell infiltrations.

RESULTS

The antral and corporal mucosal levels of IFN-gamma and IL-8 proteins were significantly higher in children with H. pylori infection than in uninfected children, but there was no such difference in the levels of IL-4 protein. The antral mucosal level of IL-8 protein was significantly higher than the corporal mucosal level of IL-8 protein in the infected children. Inflammatory cell infiltration was significantly higher in the infected children than in the uninfected children, but there were no significant correlations between mucosal cytokine levels and inflammatory cell infiltrations.

CONCLUSION

The results suggest that the predominant Th1 cytokine response and enhanced IL-8 production in the mucosa may be involved in the gastric inflammation seen in children infected with H. pylori, as well as in adult patients.

Cytokines in the gastric mucosa of children with Helicobacter pylori infection

AIM

Few studies have looked at the cytokine profile in gastric mucosa in children with Helicobacter pylori infection. This study investigated cytokines and their effects on histological abnormalities in the gastric mucosa of children with H. pylori infection.

METHODS

The levels of interferon-gamma (IFN-gamma), interleukin-4 (IL-4) and IL-8 proteins were measured in biopsy specimens from the gastric antrum and corpus of children with H. pylori infection, and related to inflammatory cell infiltrations.

RESULTS

The antral and corporal mucosal levels of IFN-gamma and IL-8 proteins were significantly higher in children with H. pylori infection than in uninfected children, but there was no such difference in the levels of IL-4 protein. The antral mucosal level of IL-8 protein was significantly higher than the corporal mucosal level of IL-8 protein in the infected children. Inflammatory cell infiltration was significantly higher in the infected children than in the uninfected children, but there were no significant correlations between mucosal cytokine levels and inflammatory cell infiltrations.

CONCLUSION

The results suggest that the predominant Th1 cytokine response and enhanced IL-8 production in the mucosa may be involved in the gastric inflammation seen in children infected with H. pylori, as well as in adult patients.

Urine-based enzyme-linked immunosorbent assay for the detection of Helicobacter pylori antibodies in children

OBJECTIVE

Recent studies of urine-based enzyme-linked immunosorbent assays (ELISA) for detection of antibody to Helicobacter pylori (H. pylori) have already shown high sensitivity and specificity in adults. The diagnostic accuracy of these assays in children was investigated.

METHODS

The results of serum and urine-based ELISAs were compared with those of 13C-urea breath tests (13C-UBT) and/or detection of faecal H. pylori antigen in 68 children. The effect of urine total immunoglobulin G (IgG) levels on the ELISA results for anti-H. pylori antibodies in urine was also examined.

RESULTS

The sensitivity, specificity and accuracy of the serum ELISA were 72.7%, 96.3%, and 92.3% respectively, while those of the urine-based ELISA were 92.3%, 76.4%, and 79.4% respectively. The level of urine total IgG in children with false-positive results in the urine-based ELISA, was significantly higher than that in children who showed negative results in both the urine-based ELISA and the 13C-UBT and/or faecal H. pylori antigen tests. Human gamma-globulin affected the urine-based ELISA results at final concentrations of 2.0 mg/dL, 3.0 mg/dL, and 4.0 mg/dL; the anti-H. pylori antibody values were significantly higher than the ELISA values without the addition of human gamma-globulin.

CONCLUSION

The findings suggested that the specificity of urine-based ELISA for detection of H. pylori antibodies is low in children, since high urinary levels of total IgG increase the likelihood of false-positive results.

Effects of stool dilution on the faecal Helicobacter pylori antigen test

OBJECTIVE

To examine the effects of stool dilution on the results of the faecal Helicobacter pylori antigen test.

METHODS

Stool samples from nine children with H. pylori infection were diluted with normal saline at dilutions of 1, 5, 10, 50, 100 and 500 times, and optical density (OD) was measured.

RESULTS

The faecal H. pylori antigen test yielded positive results for all samples at dilutions of 1:10 and less, although the sample from the case whose original stool showed the lowest OD value changed from positive to negative at a dilution of 1:50.

CONCLUSION

Our results suggest that stools at dilutions of less than 1:10 usually do not yield false-negative results in the faecal H. pylori antigen test, even in patients with low faecal antigen levels.

[Relation between serum eosinophil cationic protein (ECP) level and asthma attack in children]

Serum eosinophil cationic protein (sECP) levels were measured in 339 patients with childhood asthma, and the clinical courses of these patients were followed for 57 weeks. While considering the history and characteristics of each patient, we examined the correlation between asthma attack frequency and sECP, blood eosinophil count, and serum total IgE (tIgE) to determine their usefulness in predicting asthma attacks. Among patients with no other allergic diseases, sECP levels in patients who had no asthma attacks two weeks before or after the measurement were significantly lower than those of patients who had attacks during the same four-week period. Among patients who had attacks, those patients with no attack for a year after the measurement were also found to have low sECP levels. Similarly, even among patients with asthma attacks and high sECP levels, there were cases where attacks were well controlled using nebulizer treatments with DSCG or BDP. The incident rate of attacks for patients with other allergic diseases and a low sECP was low. Yet, there was no common trend in patients with high sECP levels. Moreover, this study detected a significant correlation between sECP level and blood eosinophil count as well as between sECP level and serum tIgE. The most significant correlation with asthma attack frequency was sECP level. Thus, sECP level seems to reflect the allergy activity level, especially two weeks prior to and after the measurement. For patients without other allergic diseases, asthma attack prediction during the two weeks period after the measurement of sECP also seems possible. Therefore, periodic measurement of sECP level is useful in objectively monitoring the improvement of symptoms and establishing the treatment plan, including treatment with DSCG or BDP.

Abnormalities of B cells and dendritic cells in SAMP1 mice

The age-related changes in the function of antigen-presenting cells (APC) were examined using a substrain of senescence-accelerated mouse (SAMP1). In the primary mixed lymphocyte reaction (MLR), dendritic cells (DC) from aged SAMP1 mice showed less stimulatory activity than those of age-matched BALB/c or young SAMP1 mice. In the secondary MLR, the stimulatory activity of B cells was found to be lower in aged SAMP1 mice but not in age-matched BALB/c or young SAMP1 mice. In addition, these age-related decreases in the stimulatory activity of APC were found to be related to changes in the surface density of major histocompatibility complex class II and intercellular adhesion molecule-1 (ICAM-1) (but not B7-1 or B7-2 molecule) on APC (DC and B cells).

Activation of thymic B cells by signals of CD40 molecules plus interleukin-10

We have previously found that thymic B cells, particularly thymic CD5+ B cells, show low responsiveness to the usual B cell stimulants such as lipopolysaccharide or anti-IgM plus interleukin (IL)-4, although they proliferate and produce antibodies after direct interaction with major histocompatibility complex class II-restricted T blasts. These findings raise the possibility that a CD40-CD40 ligand (L) interaction is involved in the activation of thymic B cells. In the present study, we therefore examine this possibility using CD40L-transfected Chinese hamster ovary (CHO) cells or anti-CD40 monoclonal antibody (mAb). When B cells in the spleen and peritoneal cavity were stimulated, they proliferated and produced immunoglobulin (Ig) in the presence of CD40L-CHO cells or anti-CD40 mAb alone. However, another signal delivered by IL-10 in addition to CD40L-CHO cells or anti-CD40 mAb was found to be necessary for thymic B cells to proliferate and secrete Ig. Other interleukins acting on B cells, such as IL-4, IL-5, and IL-6, had no effect on the activation of thymic B cells, which thus have unique characteristics not found in peripheral B cells. This report discusses the physiological significance of IL-10- and CD40-driven signals in the activation of thymic B cells.

Effect of bone marrow transplantation on antiphospholipid antibody syndrome in murine lupus mice

The (NZW x BXSB)F1 (W/BF1) mouse is known to be an animal model of systemic lupus erythematosus (SLE) and immune thrombocytopenic purpura (ITP). These mice produce not only anti-DNA antibodies but also anti-platelet antibodies, resulting in decreased platelet counts. They show a high level of proteinuria, increased white blood cell (WBC) counts, hypertension, and myocardial infarction due to the high levels of anti-cardiolipin antibodies. When W/BF1 mice (4-5 months) were lethally irradiated and then reconstituted with T cell-depleted bone marrow cells of normal BALB/c mice (8 weeks), 60% of the mice survived more than one year. The WBC and platelet counts in the mice were normalized, and the levels of anti-DNA and anti-platelet antibodies decreased. The renal dysfunction was also ameliorated as indicated by a lower level of proteinuria, lower levels of serum creatinine (S-CRTN) and blood urea nitrogen (BUN), and by improved histology. The blood pressure (BP) of the treated W/BF1 mice decreased due to the improved renal functions. In contrast to the non-treated W/BF1 mice which died of myocardial infarction or renal failure by the age of 7 months, the treated W/BF1 mice showed no evidence of myocardial infarction even one year after BMT. This was due to the lower cardiolipin levels.