RESUMO
<p><b>OBJECTIVE</b>To explore the mechamisms of mitochondria-mediated pathway in apoptosis of platelets resulted from in immune induced bone marrow failure.</p><p><b>METHODS</b>Thirty C57BL/6 mice were randomly divided into 3 groups (10 mice in each group): normal group, model group, cyclosporine A(CsA) group. Mouse model of immune bone marrow failure were established. After mouse model was successfully established, the mice in normal group and model group were given saline orally, the mice in CsA group was treated with CsA orally. Blood routine examination of mice in each group was performed by automatic blood cell analyzer; the mitochondrial membrane potential(ΔΨm), cytochrome C(Cyt C), phosphatidylserine (PS), Cawere measured by flow cytometry; expression of BAX, BAK, caspase-3, caspase-8, caspase-9 was detected by using Western blot method, the changes of bone marrow platelet ultrastructure were observed under transmission electron microscope.</p><p><b>RESULTS</b>Compared with normal group, the platelet count of model group decreased significantly, while the level of ΔΨm, caspase-3, caspase-8, caspase-9 significantly decreased, the level of Cyt C, PS, Ca, BAX, BAK increased significantly (P<0.05). Compared with the model group, the platelet count of CsA group increased obviously, while the level of ΔΨm, caspase-3, caspase-8, caspase-9 of CsA group increased significantly, the level of Cyt C, PS, Ca, BAX, BAK of CsA group decreased significantly (P<0.05). Electron microscopy showed that compared with the model group, platelet damage in CsA group were alleviated.</p><p><b>CONCLUSION</b>mitochondrial pathway plays an important role in the reduction of platelet resulted from immune bone marrow failure.</p>
RESUMO
<p><b>OBJECTIVE</b>To investigate the association of the serum level of vitamin A (VA) with the severity of pneumonia and recurrent respiratory infection (RRI) within one year after treatment in children with pneumonia, and to provide a basis for serum VA level used as an index for judgment of the condition of pneumonia and prediction of the risk of recurrent respiratory infection.</p><p><b>METHODS</b>A total of 88 children with pneumonia aged less than 3 years were enrolled as study subjects. Serum VA level was measured on admission, and the development of RRI was followed up by telephone within 1 year after discharge.</p><p><b>RESULTS</b>The children with pneumonia showed a reduction in the serum level of VA (0.8±0.3 μmol/L). The severe pneumonia group had a significantly lower serum level of VA than the mild pneumonia group (0.7±0.3 μmol/L vs 0.9±0.3 μmol/L; P<0.05), as well as a significantly higher detection rate of vitamin A deficiency (VAD) than the mild pneumonia group (63% vs 28%; P<0.05). The children were followed up for 1 year. The VAD-pneumonia group showed a significantly higher incidence of RRI than the normal VA-pneumonia group (49% vs 18%; P<0.05), while there were no significant differences in the incidence of RRI between the suspected subclinical vitamin A deficiency (SSVAD)-pneumonia group and the normal VA-pneumonia group, as well as between the VAD-pneumonia group and the SSVAD-pneumonia group (P>0.05).</p><p><b>CONCLUSIONS</b>Children with pneumonia often have a low level of VA, and the level of VA is associated with the severity of pneumonia and the development of RRI afterwards.</p>