Nitric oxide metabolities in acute rheumatic fever

Increased serum concentrations of growth differentiation factor-15 in children with acute rheumatic fever

AIM

In this single-centre prospective study, we aimed to evaluate the role of growth differentiation factor-15 in children with acute rheumatic fever.

METHODS

The study group included 25 children with acute rheumatic fever, and the control group included 25 healthy children. In addition to routine laboratory tests used in the diagnosis and treatment of acute rheumatic fever, growth differentiation factor-15 levels of the study group (at the time of diagnosis and after the treatment) and the control group were assessed and compared.

RESULTS

The mean growth differentiation factor-15 level of the study group at the time of diagnosis (918.40 ± 605.65 pg/ml) was significantly higher than the mean post-treatment level (653.08 ± 330.92 pg/ml) (p = 0.015). Similarly, the mean growth differentiation factor-15 level of the study group at the time of diagnosis was significantly higher than the control group (p = 0.04). However, mean growth differentiation factor-15 levels were similar between the groups after the treatment. Growth differentiation factor-15 was positively correlated with both C-reactive protein (p < 0.001) and erythrocyte sedimentation rate (p = 0.001) at the time of diagnosis.

CONCLUSION

Growth differentiation factor-15 levels are significantly increased in children with acute rheumatic fever at the time of diagnosis and return to similar levels with healthy children after treatment. Growth differentiation factor-15 is positively and significantly correlated with erythrocyte sedimentation rate and C-reactive protein at the time of diagnosis.

İnvestigation of endothelial dysfunction in children with acute rheumatic fever

Background:

Acute rheumatic fever (ARF) is an important cause of valvular heart disease in children. Endothelial dysfunction plays an important role in the pathogenesis of valvular heart diseases. The role of endothelial dysfunction in valvular heart diseases due to ARF is not exactly known. In ARF, autoimmune injury, inflammation, oxidative stress, and impairment of nitric oxide in valvular endothelium may be the causes of endothelial dysfunction. The purpose of this study is to evaluate endothelial dysfunction and arterial stiffness in children with ARF.

Materials and Methods:

Thirty-six patients diagnosed with ARF (the mean age was 11.80 ± 2.82 years) and 36 volunteered individuals with similar age, sex, and body mass index were included in the study. The study groups were compared in terms of M-mode echocardiography parameters, carotid arterial strain (CAS), beta-stiffness index (βSI), and flow-mediated dilation (FMD).

Results:

In patients with ARF, there was a decrease in FMD% (10.36 ± 7.26 and 12.76 ± 4.59; P < 0.001) compared to the control group. In addition, CAS (0.16 ± 0.06 and 0.18 ± 0.08; P = 0.44) and βSI (3.65 ± 1.61 and 3.57 ± 2.38; P = 0.24) were similar in the patient and the control groups. Furthermore, no correlation was detected between decreased FMD value and mitral regurgitation (r = −0.07; P = 0.66), aortic regurgitation (r = −0.04; P = 0.78), CAS (r = −0.08; P = 0.61), and βSİ (r = −0.20; P = 0.22).

Conclusion:

In our study, a decrease in FMD value, which is a marker of endothelial dysfunction, was found in children with rheumatic carditis.

Evaluation of serum ischemia modified albumin levels in acute rheumatic fever before and after therapy

OBJECTIVE

To investigate ischemia modified albumin (IMA) levels in children with acute rheumatic fever (ARF) before and after therapy and compare them with those of controls.

METHODS

Twenty seven patients with ARF and 18 healthy, age and sex matched children were included in the study. The diagnosis of ARF was established according to the modified Jones criteria. Follow-up studies were made when acute phase reactants [erythrocyte sedimentation rate (ESR), C-reactive protein (CRP)] levels returned normal. IMA levels were measured using the rapid and colorimetric method with the albumin cobalt binding test.

RESULTS

IMA levels were significantly higher in ARF group (p < 0.001) compared with controls at the time on admission. IMA (absorbance units) was measured as 0.41 ± 0.10 in the control group, 0.55 (0.44-1.13) in the study group before treatment and 0.48 ± 0.12 in the study group after treatment. After treatment, statistically important decrements were determined in the levels of ESR (p<0.001), CRP (p<0.001) and IMA (p<0.01). There was no significant difference for IMA levels between after treatment and control group. IMA levels at the time on admission correlated positively with ESR (r = 0.605, p < 0.01) and CRP (r = 0.543, p < 0.01).

CONCLUSIONS

The present study shows that increased serum IMA levels in patients with ARF at the time of diagnosis is a sign of increased inflammation. Thus, serum IMA levels may be used as a follow-up marker like CRP and ESR for evaluating the efficacy of treatment in ARF.

Fragmented QRS is predictive of myocardial dysfunction, pulmonary hypertension and severity in mitral stenosis

Reliable non-invasive new indices reflecting severity of rheumatic valve disease would be highly beneficial. Recently, presence of fragmented QRS (fQRS) in ECG was accepted as a marker of myocardial fibrosis. fQRS is defined as the presence of RSR' patterns such as additional R wave (R'), notching in the R wave or the S wave in 2 contiguous leads. Purpose of our study was to establish frequency of fQRS in isolated rheumatic mitral stenosis compared with control group. We studied 193 patients with mitral stenosis and age/gender matched 97 healthy subjects. Patients were categorized according to the New York Heart Association (NYHA) functional class. Severity of mitral stenosis, left ventricular ejection fraction, and pulmonary artery pressure were obtained by means of echocardiography. fQRS was defined on routine 12-lead ECG. fQRS was more frequent in subjects with mitral stenosis than in control group (p < 0.001). fQRS was associated with low ejection fraction, pulmonary hypertension, poor functional NYHA class, increased mean mitral valve gradient and decreased mitral valve area (R = 0.1, p = 0.02; R = 0.1, p = 0.001; R = 0.1, p = 0.01; R = 0.1, p = 0.04; and R = -0.1, p = 0.009, respectively). Mitral valve area was the only independent predictor of fQRS in multiple logistic regression analysis. In conclusion, fQRS is predictive of severe mitral stenosis, lower ejection fraction, increased pulmonary artery pressure, and poor functional class. fQRS might be considered as a novel indicator of mitral stenosis severity and associated complications.

Study of correlation between lead-induced cytotoxicity and nitric oxide production in PC12 cells

Despite reduction in its exposure, lead remains a major health problem. The primary target of lead toxicity is the central nervous system. The cellular, intracellular and molecular mechanisms of lead neurotoxicity are numerous, such as induction of apoptosis and interfering with Ca2+ dependent enzyme like nitric oxide synthase (NOS). To investigate the cytotoxic effect of lead on rat pheochromocytoma (PC12) cells, as a suitable model for neuroscience study, and possible correlation between lead toxicity and nitric oxide (NO) production, this study was performed. The current results showed that lead could induce cytotoxicity as well as NO production in a dose dependent manner in PC12 cells after 24h. The cytotoxicity was positively correlated with increased NOx (nitrite and nitrate) production in these cells. L-NAME, a NOS inhibitor, treatment (2.5 mM) could reverse this cytotoxicity. It can be concluded that lead-induced cytotoxicity in PC12 cells could partly be mediated by higher NO production.