Implantation of muscle satellite cells overexpressing myogenin improves denervated muscle atrophy in rats

This study evaluated the effect of muscle satellite cells (MSCs) overexpressing myogenin (MyoG) on denervated muscle atrophy. Rat MSCs were isolated and transfected with the MyoG-EGFP plasmid vector GV143. MyoG-transfected MSCs (MTMs) were transplanted into rat gastrocnemius muscles at 1 week after surgical denervation. Controls included injections of untransfected MSCs or the vehicle only. Muscles were harvested and analyzed at 2, 4, and 24 weeks post-transplantation. Immunofluorescence confirmed MyoG overexpression in MTMs. The muscle wet weight ratio was significantly reduced at 2 weeks after MTM injection (67.17±6.79) compared with muscles injected with MSCs (58.83±5.31) or the vehicle (53.00±7.67; t=2.37, P=0.04 and t=3.39, P=0.007, respectively). The muscle fiber cross-sectional area was also larger at 2 weeks after MTM injection (2.63×103±0.39×103) compared with MSC injection (1.99×103±0.58×103) or the vehicle only (1.57×103±0.47×103; t=2.24, P=0.049 and t=4.22, P=0.002, respectively). At 4 and 24 weeks post-injection, the muscle mass and fiber cross-sectional area were similar across all three experimental groups. Immunohistochemistry showed that the MTM group had larger MyoG-positive fibers. The MTM group (3.18±1.13) also had higher expression of MyoG mRNA than other groups (1.41±0.65 and 1.03±0.19) at 2 weeks after injection (t=2.72, P=0.04). Transplanted MTMs delayed short-term atrophy of denervated muscles. This approach can be optimized as a novel stand-alone therapy or as a bridge to surgical re-innervation of damaged muscles.

Study on detecting antibodies to Toxoplasma gondii in pooled serum of blood donors by Dot-IGSS.

To prevent post-transfusion toxoplasmosis, the sera of blood donors, per six of which were mixed as a pool, were examined for anti-Toxoplasma gondii antibiodies by Dot-immunogold silver staining (Dot-IGSS) with the single serum specimens examined simultaneously. The results showed that the sensitivity and specificity of serum pool method were 92.31% and 99.96% respectively. The consistent rate between the two methods was 99.73% and kappa value was 0.947 (p<0.01). Considering the mean infection rate of Toxoplasma gondii being 4.86% in China, if the serum pool method be adoped, with pool size k=5, a 57% reduction in the number of tests, as well as the cost of the screen, can be expected. Beside the social benefit, consequent upon the interruption of the Toxoplasma gondii infection spread through blood transfusion also can be expected.

Dose findings of dihydroartemisinin in treatment of falciparum malaria.

Forty patients with uncomplicated P. falciparum malaria were respectively treated in an open randomized comparative study of dihydroartemisinin tablets given at total doses of 480 mg over 5 days and 640 mg over 7 days in a drug-resistant malaria endemic area in Hainan, China. The result showed that all patients were clinically cured. In 5-day and 7-day groups, the mean fever clearance times (FCT) were 26.1+/-10.2 and 21.1+/-11.8 hours respectively; the mean parasite clearance times (PCT) were 58.7+/-20.9 and 59.4+/-20.9 hours respectively, which showed no significant difference. 28-day follow-ups were accomplished on 39 and 37 cases respectively in two groups, the recrudescence rates were 20.5% (8/39) in 5-day group, while 2.7% (1/37) in 7-day group with significant difference (chi2=4.19, p<0.05). No clinical drug-related side effect was found in two groups during treatment.