Bone marrow mesenchymal stem cells improve learning ability of the aging rat / 中国组织工程研究

BACKGROUND: At present, studies have shown that bone marrow mesenchymal stem cells (BMSCs) have self-renewal ability, which can be used as ideal seed cells for repairing tissue and organ damages caused by aging and lesions. OBJECTIVE: To study the changes in the levels of oxidation, inflammatory factors and neurotrophic factors (BDNF) in the brain of aging rats undergoing BMSCs transplantation, and to analyze the mechanism underlying the repair of learning and memory ability in the aging rats. METHODS: A total of 30 clean Sprague-Dawley rats were randomly divided into control group, model group and BMSCs group, 10 rats in each group. Aging models were made in the rats by 3-month subcutaneous injection of D-galactose. After modeling, BMSCs treatment was performed via tail vein injection in the BMSCs group.The injection was performed once a week,for 8 continuous weeks.Morris water maze was used to detect the learning and memory abilities of the rats in each group after the final injection of BMSCs. Superoxide dismutase activity in the brain tissue of rats was detected by xanthine oxidase method. Level of malondialdehyde in the rat brain tissue was detected by thiobarbituric acid method. Total antioxidant capacity of the brain tissue was detected by Fe3+reduction method. Real-time PCR and western blot assay were used to detect the expression of brain-derived neurotrophic factor mRNA and protein in the brain tissue of the aging rat, respectively. RESULTS AND CONCLUSION: Compared with the model group, the BMSCs group exhibited significantly higher activity of superoxide dismutase, stronger total antioxidant capacity, and higher levels of brain-derived neurotrophic factor mRNA and protein (P < 0.05), but the lower malondialdehyde level in the brain (P < 0.05). Compared with the model group, there was less time and higher frequency for passing through the platform in the BMSCs group (P < 0.05). Our findings further indicate that BMSCs can improve the abilities of learning and memory in aging rats, and the underlying mechanism is likely to improve antioxidant capacity and to regulate the level of brain-derived neurotrophic factors.

Vitamin D level in children with bloodstream infection / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the difference in serum 25(OH)D level between children with bloodstream infection and healthy children.</p><p><b>METHODS</b>A case-control study was conducted among 60 children with bloodstream infection who were hospitalized between January 2010 and December 2013 and had positive results of two blood cultures. Meanwhile, 60 aged-matched healthy children who underwent physical examination during the same period of time were enrolled as the healthy control group. Chemiluminescence was applied to measure the serum 25(OH)D level, and the constituent ratios of children with different serum 25(OH)D levels were compared between the two groups.</p><p><b>RESULTS</b>The bloodstream infection group had a significantly lower serum 25(OH)D level than the healthy control group (P<0.01). Compared with the healthy control group, the bloodstream group had significantly lower constituent ratios of children with normal Vitamin D level (8% vs 35%) or vitamin D insufficiency (22% vs 43%) (P<0.05). Compared with the healthy control group, the bloodstream group had significantly higher constituent ratios of children with vitamin D deficiency (42% vs 13%) or severely vitamin D deficiency (28% vs 8%) (P<0.01).</p><p><b>CONCLUSIONS</b>Vitamin D insufficiency prevails among children, and children with bloodstream infection have a significantly lower serum 25(OH)D level than healthy children.</p>

Effect of low-dose methylprednisolone on serum TNF-α level in children with Mycoplasma pneumoniae pneumonia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the effect of low-dose methylprednisolone on serum tumor necrosis factor alpha (TNF-α) level in children with Mycoplasma pneumoniae pneumonia (MPP).</p><p><b>METHODS</b>A case-control study was conducted among 38 children with MPP who received treatment in the Affiliated Hospital of Yan'an University between January and December 2012, and who had not received glucocorticoids before hospitalization. They were randomly divided into methylprednisolone treatment (n=20) and conventional treatment groups (n=18). The methylprednisolone treatment group was administered with methylprednisolone (1 mg/kg·d) by intravenous drip for three days in addition to conventional treatment. Serum samples were collected from both groups before treatment and on days 4 and 7 of treatment. Twenty-five children who underwent physical examination in the healthcare clinic during the same period were randomly selected as a normal control group, and serum samples were collected on the same day that the physical examination was performed. Serum TNF-α levels in the three groups were measured using enzyme-linked immunosorbent assay.</p><p><b>RESULTS</b>On admission, the methylprednisolone treatment and conventional treatment groups had significantly higher serum TNF-α levels than the normal control group (P<0.01), but there was no significant difference between the methylprednisolone treatment and conventional treatment groups. On days 4 and 7 of treatment, the methylprednisolone treatment group had significantly lower serum TNF-α levels than the conventional treatment group (P<0.05; P<0.01). On day 7 of treatment, there was no significant difference in serum TNF-α level between the methylprednisolone treatment and normal control groups, but the conventional treatment group still had a significantly higher serum TNF-α level than the normal control group (P<0.01).</p><p><b>CONCLUSIONS</b>Low-dose methylprednisolone can significantly decrease serum TNF-α level and inhibit inflammatory response in children with MPP, and may reduce damage caused by inflammatory response.</p>

Effects of Recombinant Human Erythropoietin on Immune Function of Chemotherapy Mice / 实用儿科临床杂志

Objective To observe the effects of recombinant human erythropoietin(rh-EPO) on immune function of cyclophosphamide-treated mice.Methods Six-week-old mice were randomly divided into 4 groups.Cyclophosphamide plus normal saline group(CTX(+NS));cyclophosphamide plus lower and higher dosage rh-EPO group(CTX+LDrh-EPO and CTX+HD rh-EPO);normal saline control group(NS).The changes of Hb,WBC,red blood cell immune function((C_3b)-R%),T lymphocyte proliferative responsiveness optical density index A(A score),IL-2,TNF-? of 4 groups were observed.Results The CTX + NS group showed lower levels on Hb,WBC,C_(3b)-R%,A score,IL-2 and TNF-? compared with NS normal control group(P0.05).There were positive correlation between C_(3b)-R% and Ascore,C_(3b)-R% and IL-2.Conclusions 1.Cyclophosphamide treated mice have lower Hb,WBC,C_(3b)-R%,A,IL-2 and TNF-? secretion.2.rh-EPO administration have improvements with Hb,RBC immune function,T lymphocyte proliferative responsiveness and IL2 production.