Morphology and function of platelets stored in modified platelet additive solution at low temperature / 中国实验血液学杂志

The aim of study was to evaluate the function of modified platelet additive solution (PAS-IIIM) with trehalose as a substitute of plasma for the storage of platelet concentrates at low temperature (10 degrees C). Apheresis platelets from 6 donors were divided and added with different media (group A: 100% plasma; group B: 70% PAS-IIIM/30% plasma; group C: 100% plasma/trehalose). Groups A, B, C were stored at 10 degrees C, 22 degrees C and -85 degrees C separately. In addition, group D (platelet concentrates stored with 100% plasma at 4 degrees C) was set up as control group for scan electronmicroscopy. The samples of each platelets were collected on day 0, 1, 5, 7 and 9 after storage respectively, while samples of platelets stored at -85 degrees C (group C) were collected on day 20 after storage. CD62p, hypotonic shock response (HSR), platelet aggregation, lactic dehydrogenase (LDH) and morphology of platelets were evaluated. The results showed that the expressions of CD62p in groups A and B increased in a time-dependent manner, but HSR and platelet aggregations decreased. The expression of CD62p, LDH release, and platelet aggregation in group A were significant higher than that in group B (p < 0.05). HSR in group A was significant lower than that in group B (p < 0.05). LDH release was significant high in samples of group C and the expression of CD62p was lower than that in other two groups (p < 0.05). It is concluded that the protective effects of 70% PAS-IIIM/30% plasma (10 degrees C) and plasma platelets (22 degrees C) on morphology of platelets are similar, but better than those of plasma platelets (4 degrees C) and plasma/trehalose (-85 degrees C). In short, PAS-IIIM serves as a good substitute of plasma for platelet storage, and protects the chilled platelets.

Optimization of culture measure for bovine-bovine and goat-bovine cloned embryos in vitro / 生物工程学报

<p><b>UNLABELLED</b>This study is conducted to explore an effective culture method for supporting the embryo development. The cattle fetal ear fibroblasts and the goat fetal ear fibroblasts are transplanted into the enucleated cattle oocytes separately by oocyte intraplasmic nuclear injection method to construct bovine cloned embryos and goat-bovine cloned embryos. The embryos are first cultivated in modified charles rosenkrans 2 amino acid medium (mCR2aa) and modified synthetic oviduct fluid medium (mSOF) separately. Then BSA (8 mg/mL) or FBS (10%) can be added to mSOF according to the different culture period. The supplements and orders, added during the first three days and after three days are as follow: BSA and BSA, BSA and FBS, FBS and BSA, FBS and FBS. On the basis of the cleavage rate, 8/16-cell rate, blastocysts rate and total cell number of blastocysts, the best culture way can be screened out.</p><p><b>RESULT</b>First, cleavage rate, 8/16-cell rate, blastocysts rate and total cell number of blastocysts, cultivated in mSOF solution are all higher than those cultivated in mCR2aa( P < 0.05). Second, the cleavage rate and 8/16-cell rate, adding BSA and FBS into mSOF, are in turn 79.8% +/- 7.1%, 49.7% +/- 3.5%, 21.5% +/- 1.8%, and 115.2 +/- 4.3 in bovine cloned embryo, and 40.1% +/- 6.3%, 29.2% +/- 2.0%, 13.4% +/- 2.1% and 100.1 +/- 3.0 in goat-bovine cloned embryo, which are significant higher than other culture groups (P < 0.05).</p><p><b>CONCLUSION</b>The goat-bovine cloned embryo can be cultivated by the optimized culture measure of bovine cloned embryo. The best culture ways of bovine cloned embryo and goat-bovine cloned embryo are all to use mSOF supplemented BSA in the first three days and then use mSOF supplemented FBS in the next five days.</p>

The application of co-culture system on the in vitro development of bovine somatic nuclear transferred embryos / 生物工程学报

To establish a co-culture system of nuclear transferred embryos in bovine, effects of co-culture cell types, passages and cryopreservation as well as addition of BFF or FBS were investigated. The results showed that embryos co-cultured with oviductal epithelial cell and granulosa cell achieved significantly higher blastocyst rate compared with the control group (P < 0.05) and co-cultured with oviductal epithelial cell had more embryo cell number than those with granulosa cell. Passages of co-culture cells significantly affected the blastocyst rate and embryo cell number (P < 0.05), and cryopreservation decreased the blastocyst rate and embryo cell number remarkably. Supplemention of BFF increased blastocyste rate significantly (P < 0.05). In conclusion, co-cultured with fresh primary oviductal epithelial cell along with addition of 10% BFF in SOFaa could improve development of nuclear transferred bovine embryo in vitro.

Gene transfer of von Hippel-Lindau inhibits the growth of transplanted solid tumors / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To explore the effect of von Hippel-Lindau(VHL) gene on growth of EL-4 solid tumors in vivo.</p><p><b>METHODS</b>C57BL/6 mice model of solid tumors was established by subcutaneous injection of EL-4 lymphoma cells. Mice were randomly divided into two groups as treatment group (n=6) and control group (n=6) when tumor diameter increased to 0.1 cm and 0.4 cm respectively. Plasmid pcDNA3-VHL was injected into solid tumor in treatment group, empty pcDNA3 vector in control group. The growth of tumor was observed. Immunohistochemistry and Western blot analysis were used to examine the transgenic expression of VHL, hypoxia inducible factor-1alpha (HIF)-1alpha, bcl-2 and VEGF. Microvessel density (MVD) and apoptosis index (AI) of tumors were also detected.</p><p><b>RESULTS</b>VHL gene transfer eradicated tumors with small size (0.1 cm diameter), but it only retarded the growth of large tumors (0.4 cm diameter). VHL was overexpressed, the expression levels of VEGF, HIF-1alpha and bcl-2 were reduced in treatment group compared with those in the control group. The level of MVD was significantly lower in treatment group (P< 0.05), but AI was higher in treatment group compared with those in the control group (P< 0.01).</p><p><b>CONCLUSION</b>VHL gene therapy can inhibit the growth of EL-4 solid tumor in vivo.</p>

Study on anti-HBV effects of genetically engineered replication-defective hepatitis B virus expressing dominant negative mutants of core protein / 中华实验和临床病毒学杂志

<p><b>BACKGROUND</b>To explore the possibility of using HBV as a gene delivery vector, and to test the anti-HBV effects by intracellular expression of dominant negative mutants of core protein.</p><p><b>METHODS</b>Two kinds of full length mutant HBV genome, which express Core-partial P and Core-S fusion protein, were transfected into HepG 2.2.15 cell lines. Positive clones were selected and mixed in respective groups with hygromycin in the culture medium. HBsAg and HBeAg, which exist in the culture medium, were tested by ELISA and intracellular HBc related HBV DNA was examined by dot blot hybridization. The existence of recombinant HBV virion in the culture medium was examined by PCR.</p><p><b>RESULTS</b>The mean inhibitory rates of HBsAg were 2.74+/-3.83%, 40.08+/-2.05% (P less than 0.01) and 52.94+/-1.93% (P less than 0.01) in group 2.2.15-pMEP4, 2.2.15-CP and 2.2.15-CS, respectively. The mean inhibitory rates of HBeAg were 4.46+/-4.25%, 52.86+/-1.32% (P less than 0.01) and 41.60+/-1.65% (P less than 0.01), respectively. The inhibitory rates of HBc related HBV DNA were 15.3%, 82.0% and 67.2%, respectively. Recombinant HBV virion was detectable in the culture medium of only group 2.2.15-CP.</p><p><b>CONCLUSION</b>Dominant negative mutants of core protein can efficiently suppress wt-HBV replication and the expressions of HBV antigens. With the help of wild-type HBV, the recombinant HBV genome can form and secret HBV like particles, which provides evidence that the antiviral gene will be hepatotropic expression and the antiviral effects will be amplified.</p>