BACKGROUND:Current researches on whether the intramuscular injection of heterogeneous umbilical cord mesenchymal stem cells (UC-MSCs) is safe or not lack theoretical basis. OBJECTIVE:To explore the effects of intramuscular injection of heterogeneous UC-MSCs on expression of myocardial vascular endothelial growth factor (VEGF), cardiac troponin I (cTnI) and serum VEGF, hepatocyte growth factor (HGF), insulin-like growth factor 1 (IGF-1) and granulocyte macrophage colony stimulating factor (GM-CSF) in normal Wistar rats. METHODS:A total of 60 Wistar rats were divided into six groups randomly. Rats in the six groups were respectively administrated with intramuscular injection of PBS, Dulbecco’s modified Eagle’s medium, hUC-MSC supernatant, 0.25×105, 1.0×105, 4.0×105 hUC-MSCs. Rats received a second intramuscular injection 4 weeks after first injection. Eight weeks later, the blood sample and myocardial tissue were taken. The serum concentration of VEGF, HGF, IGF-1 and GM-CSF were measured with enzyme-linked immunosorbent assay kit. The myocardial VEGF and cTnI expression were detected by immunohistochemical technique. RESULTS AND CONCLUSION:There was no significant difference in the serum concentration of the VEGF, HGF, IGF-1 and GM-CSF among the groups before and after injection (P>0.05). In the same group, no statistical significant changes in the serum concentration of the VEGF, HGF, IGF-1 and GM-CSF were found among the rats before and after injection (P>0.05). Eight weeks after injection, weak positive expression of the VEGF in the cytoplasm of cardiocytes in the six groups was observed, and strong positive expression of the cTnI in the cytoplasm of cardiocytes in the six groups was observed. There was no significant difference in the VEGF and cTnI content in the myocardium among the groups (P>0.05). Intramuscular injection of hUC-MSCs or the supernatant of hUC-MSCs had no effects on the serum concentration of the VEGF, HGF, IGF-1, GM-CSF and the myocardial VEGF and cTnI expression in normal Wistar rats.

Objective To investigate the immunological pathogenesis of Kawasaki disease( KD)through examination of changes in the expression of suppressors of cytokine signaling 1(SOCS1)and SOCS3,helper T cells and CD4 + CD25 + regulatory T cells(CD4 + CD25 + Treg)in peripheral blood from children with acute KD. Methods Six-teen children[10 boys,6 girls,aged 1 - 2 years old,averaged(1. 6 ± 0. 3)years old]in the acute phase of KD(KD group),16 children[9 boys,7 girls,aged 1 - 3 years old,averaged(1. 5 ± 1. 1)years old]with pneumonia(pneumo-nia group)and 8 normal children[5 boys,3 girls,aged 1 - 5 years old,averaged(2. 0 ± 1. 1)years old]of the same age(normal control group)from the Affiliated Hospital of Qingdao University who were admitted from October 2012 to March 2013 were recruited. The mRNA levels of SOCS1 and SOCS3 in the T cells from peripheral blood were examined by way of reverse transcription - polymerase chain reaction(RT - PCR). Interferon - γ( IFN - γ),interleukin - 4 (IL - 4)and CD4 + CD25 + Treg were quantified by means of fluorescence activated cell sorting(FACS). Results The expressions of SOCS1 and SOCS3,the percentage of IL - 4 T cells observed in the peripheral blood of the pneumonia group were similar to the normal control group(P ﹥ 0. 05),but significantly decreased in the percentage of INF - γ and the level of CD4 + CD25 + Treg(t = 3. 71,12. 81,all P ﹤ 0. 05). Compared to the normal control group and the pneumo-nia group,the expressions of SOCS1 and SOCS3,the percentage of INF - γ and IL - 4 T cells decreased significantly in the peripheral blood of the KD group(t = 2. 27,4. 48,17. 64,2. 73,2. 74,1. 25,2. 36,2. 59,all P ﹤0. 05 ). On the other hand,the level of CD4 + CD25 + Treg in the peripheral blood of the KD group was markedly lower than that in the normal control group(t =7. 70,P ﹤0. 05),but similar to the pneumonia group(P ﹥0. 05). Conclusions The function of helper T cells is inhibited in acute KD. The CD4 + CD25 + Treg may be involved in the immunological pathogenesis of KD.

Objective The 3243A ＞ G mutation in mitochondrial DNA is a common cause of the classical mitochondrial diseases characterized by neuro-muscular disorders.This study reports a rare case with the main manifestations of mitochondrial disease in children of mitochondrial cardiomyopathy and respiratory muscle damage.Methods The clinical characteristics,diagnosis and treatment,biochemical,pathological and genetic features of a 10-year-old girl were studied.Results The girl was admitted because of heart failure and respiratory failure at the age of 10.Ragged red fibers in skeletal muscles had been noticed.On her mitochondrial gene,3243A ＞ G mutation,Leu tRNA (UUR),was detected.The mutation rate in the peripheral blood cells was 94％.After the treatment with a high dose of creatine phosphate sodium,coenzyme Q10 and L-carnitine with assisted ventilation,the patient improved rapidly.The child was followed up for 2 years without recurrence.Meanwhile the growth,development and daily life were normal.Conclusions Cardiac and respiratory muscle impairments that appeared at the same time as the first manifestations of the children's mitochondrial disease is not common,and it is rare to have cardiomyopathy based mitochondrial gene 3243A ＞ G mutation is seldom seen clinically.Skeletal muscle biopsy and genetic test is the key for accurate diagnosis.Improving mitochondrial metabolism and assisted ventilation appear to be helpful treatments.

Objective:To summarize the clinical phenotype and genotype features of 2 children with adenosine deaminase 2 (ADA2) deficiency, and to review the related literature so as to enhance the understanding of this disease.Methods:The phenotype and genotype of 2 cases with ADA2 deficiency who visited the Affiliated Hospital of Qingdao University from March to December 2019 were analyzed.Literature was searched from foreign and domestic databases and studied to summarize clinical and gene mutation characteristics of children with ADA2 deficiency.Results:(1) ADA2 gene mutation was found in both children.One case was characterized by recurrent fever, livedo reticularis, polyarteritis nodosa and immunodeficiency.The mutation site c. 571delC(p.Q191Sfs*5)of the ADA2 gene detected in this case was a homozygous mutation, which was a new mutation point and not reported in China or abroad previously.The other case was characterized by recurrent fever, panniculitis, vasculitis with legs, and immunodeficiency.The mutation site c. 1358A>G(p.Y453C)was a homozygous mutation that was not reported in China previously.(2)There were 171 cases of children diagnosed with ADA2 deficiency in foreign countries, but only 5 cases (3 previously reported cases and 2 cases in this study) were detected in China.The main clinical phenotypes were recurrent fever(5/5 cases), livedo reticularis(4/5 cases), panniculitis(1/5 cases), cutaneous gangrene(1/5 cases), growth retardation(1/5 cases), cerebral infarction(3/5 cases), humoral immunodeficiency(4/5 cases), blood system involvement(3/5 cases), and myalgia(2/5 cases), elevated inflammatory markers(C-reactive protein, erythrocyte sedimentation rate)(5/5 cases). Conclusions:Children with ADA2 deficiency have various clinical phenotypes, and a good understanding of phenotypes can improve the level of clinical diagnosis and treatment.The mutation point of c. 571delC is a novel ADA2 gene mutation type, which further enriches the ADA2 gene spectrum.