BACKGROUND:Bone marrow mesenchymal stem cells (BMSCs) transplantation can promote cardiac repair after myocardial infarction, but it has been limited by the low cellsurvival rate.
OBJECTIVE:To study the effect of hydrogen sulfide (H 2 S) on the BMSCs transplantation for treatment of myocardial infarction.
METHODS:BMSCs were separated and cultivated form Sprague-Dawley rats weighing (100±20) g. The 4th generation cells were used for later experiment, and marked by DAPI at 2 hours before use. Fifty male Sprague-Dawley rats, weighing (200±20) g had been divided into five groups:Sham group (n=10) and four transplantation groups:BMSCs (n=10), H 2 S-BMSCs (n=10), H 2 S (n=10), normal saline (n=10). The myocardial infarction model of four groups was established except of sham group (only thread without ligation). The cardiac function was measured by echocardiogram at 4 weeks after celltransplantation. The col agen in the infarction area was tested by Masson staining.
RESULTS AND CONCLUSION:Severe myocardial fibrosis was found in the normal saline group, with no myocardial regeneration in the infarct area. H 2 S-BMSCs group had less col agen and more cardiac muscle tissue than BMSCs or H 2 S groups. Left ventricular ejection fraction and left ventricular fractional shortening of the H 2 S-BMSCs group were significantly higher than those of the BMSCs or H 2 S groups (P<0.05). The cells survival rate and cardiac function of myocardial infarction rats can be promoted by H 2 S-preconditioned BMSCs transplantation, which is superior to BMSCs or H 2 S alone.

Objective To compare the efficacy of tibial tuberosity osteotomy (TTO) combined with medial patellofemoral ligament reconstruction (MPFLR) with simple TTO in treatment of recurrent patella dislocation associated with patella alta.Methods From July 2010 to December 2015,50 patients with recurrent patella dislocation and patella alta were included in this study.There were 15 males and 35 females with an average age of 20.6 years.These patients received surgical treatment and their clinical data were collected and retrospectively analyzed by case-control study.According to surgical methods,patients were divided into TTO group (32 cases) and MPFLR + TTO group (18 cases).The differences between preoperative status and postoperative status were evaluated by knee function scores including Tegner,international knee documentation committee (IKDC),Kujala scores,knee injury and osteoarthritis outcome score (KOOS).Patellar stability was checked at the last follow-up visit.Results The TTO group and MPFLR + TTO group were followed up for (50.9 ± 17.8) months and (22.3± 10.1)months,respectively.Two patients occurred recurrent dislocation in TTO group,who showed positive in both extrapolation test and extrapolation apprehension test at 0°flexions of knee.All patients in MPFLR + TTO group did not occur recurrent dislocation,who showed negative in both extrapolation test and extrapolation apprehension test at 0° flexions of knee.There was no significant difference between preoperative and postoperative results in TTO group in Tegner score (P ＞ 0.05),KOOS scores in pain and daily life activities subdomains (P ＞ 0.05),while differences in the rest of scores were statistically significant (P ＜ 0.05).Compared with TFO group,the differences of all scores were statistically significant (P ＜ 0.05) and KOOS scores in the pain and daily life activities subdomains were significantly improved postoperatively in MPFLR + TTO group P ＜0.05).Conclusions For patients with recurrent patellar dislocation associated with patella alta,both surgical methods are found to be effective.Postoperative improvements in pain and daily life activities are less obvious in TTO.While postoperative improvements in pain and daily life activities in MPFLR + TTO are superior to those of TTO.

ObjectiveTo investigate the effects of Dihuang Yinzi on the cognitive function in the mouse model of learning and memory impairments induced by scopolamine （SCOP） and explore the treatment mechanism. MethodsA mouse model of learning and memory impairment was induced by intraperitoneal injection of SCOP. Sixty male C57BL/6J mice were randomized into six groups： control （0.9% NaCl， n=10）， model （SCOP 1 mg·kg^-1·d^-1， n=10）， low-， medium-， and high-dose Dihuang Yinzi （SCOP 1 mg·kg^-1·d^-1 + Dihuang Yinzi 5.5， 11.0， and 22.0 g·kg^-1·d^-1， n=10）， and donepezil （SCOP 1 mg·kg^-1·d^-1 + donepezil 0.84 mg·kg^-1·d^-1， n=10）. Mice were administrated with corresponding drugs for 6 weeks. Modeling started in the 4th week， and mice in other groups except the control group were injected with SCOP intraperitoneally 40 min after daily gavage. Behavioral testing began in the 5th week， 30 min after modeling each day. The Morris water maze and novel object recognition tests were carried out to evaluate the spatial learning and memory function of mice. Nissl staining was employed to observe the survival of neurons and Nissl bodies in the hippocampal CA1 region. Western blot was employed to determine the protein levels of silent information regulator 2 （SIRT2）， α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid （AMPA） receptor 1 （GluA1）， protein kinase A （PKA）， cAMP response element-binding protein （CREB）， phosphorylated-CREB （p-CREB）， postsynaptic density protein 95 （PSD95）， growth-associated protein-43 （GAP-43）， and synaptophysin （SYN） in the hippocampus. Immunofluorescence was used to detect the expression of doublecortin （DCX） in the hippocampal dentate gyrus （DG） region. ResultsCompared with the control group， the model group showed impaired learning and memory （P<0.01）， obvious neuronal damage in the hippocampal CA1 region， a reduction in neuron survival （P<0.01）， a decrease in DCX expression in the hippocampal DG region （P<0.01）， down-regulated proteins levels of GluA1， PKA， p-CREB/CREB， PSD95， SYN， and GAP-43 in the hippocampal tissue （P<0.05， P<0.01）， and an up-regulated protein level of SIRT2 （P<0.01）. Compared with the model group， the medium- and high-dose Dihuang Yinzi groups and the donepezil group showed improvements in learning and memory （P<0.05， P<0.01）， while the low-， medium-， and high-dose Dihuang Yinzi groups and the donepezil group had increased neuron survival （P<0.05， P<0.01）. The medium-dose Dihuang Yinzi group and the donepezil group showed increased DCX expression （P<0.05， P<0.01）. The medium- and high-dose Dihuang Yinzi groups and the donepezil group showed up-regulation in the protein levels of GluA1， PKA， p-CREB/CREB， PSD95， SYN， and GAP-43 （P<0.05， P<0.01） and down-regulation in the protein level of SIRT2 （P<0.01）. ConclusionDihuang Yinzi can improve the cognitive function in the mouse model of learning and memory impairments induced by SCOP by inhibiting the upregulation of SIRT2， activating the PKA/CREB signaling pathway， improving synaptic plasticity， and reducing hippocampal neuronal damage.