Verification of suitable and reliable reference genes for quantitative real-time PCR during adipogenic differentiation in porcine intramuscular stromal-vascular cells.

Intramuscular fat (IMF) is an important trait influencing meat quality, and intramuscular stromal-vascular cell (MSVC) differentiation is a key factor affecting IMF deposition. Quantitative real-time PCR (qPCR) is often used to screen the differentially expressed genes during differentiation of MSVCs, where proper reference genes are essential. In this study, we assessed 31 of previously reported reference genes for their expression suitability in porcine MSVCs derived form longissimus dorsi with qPCR. The expression stability of these genes was evaluated using NormFinder, geNorm and BestKeeper algorithms. NormFinder and geNorm uncovered ACTB, ALDOA and RPS18 as the most three stable genes. BestKeeper identified RPL13A, SSU72 and DAK as the most three stable genes. GAPDH was found to be the least stable gene by all of the three software packages, indicating it is not an appropriate reference gene in qPCR assay. These results might be helpful for further studies in pigs that explore the molecular mechanism underlying IMF deposition.

Comparison between meat quality of Hanzhong White pigs and carcass weight.

A total of 48 carcasses of crossbred Hanzhong White pigs were divided into 3 groups (I, 90-99 kg; II, 100-109 kg; III, 110-119 kg) to investigate the influence of carcass weight on meat quality. The intramuscular fat content of the 3 groups increased from 1.90 to 4.90%; for meat color, Warner-Bratzler shear force, drip loss, and oxidation-type muscle fiber percentage, and muscle fiber diameter of the longissimus lumborum, the indices in group II and group III were better than those in group I (P < 0.05). The saturated fatty acid and polyunsaturated fatty acid percentages of the longissimus lumborum muscle (2.80 and 37.30%, respectively) in group II were significantly lower than those in the other 2 groups, while the monounsaturated fatty acid percentage was the highest (59.10%). In conclusion, our results suggest that a carcass weight of 100-109 kg is sufficient to produce acceptable meat quality of Hanzhong White pigs.

Correlation of forkhead box transcription factor O1 and myosin heavy chain isoforms in porcine skeletal muscle.

We examined the expression of myosin heavy chain (MyHC) isoforms and forkhead box transcription factor O1 (FoxO1) in porcine soleus and extensor digitorum longus (EDL) muscles to clarify the correlation of FoxO1 and the relative abundance of transcripts of MyHC isoforms. Soleus muscle was found to be redder than EDL muscles in pigs, and immunohistochemical fast MyHC staining showed more oxidative type I fibers compared to EDL. qRT-PCR quantification of MyHC isoforms I, IIa, IIx, and IIb showed that expression of MyHC I and MyHC IIa mRNAs was much higher, whereas expression of MyHC IIx and MyHC IIb mRNAs was much lower in porcine soleus muscle compared to EDL muscle. Expression of FoxO1 mRNA and p-FoxO1 protein was significantly more abundant in porcine soleus muscle compared to EDL muscle. The expression of phosphorylated FoxO1 (p-FoxO1) was positively correlated with the expression of MyHC I (R = 0.9747, P < 0.01) and negatively correlated with the expression of MyHC IIx (R = -0.9963, P < 0.01) and MyHC IIb (R = -0.9834, P < 0.01). Taken together, these results suggested that FoxO1 may play a pivotal role in the determination of muscle fiber type.

Combined endovascular embolization of large intracranial arteriovenous malformations and their subsequent surgical resection.

Twelve patients with large arteriovenous malformations (AVMs) were subjected to endovascular embolization followed by surgery. Of the 12 patients, 9 were males and 3 females. Their age ranged from 11 to 37 years. Eleven AVM nidi were more than 6 cm in diameter and one AVM, located in a crucial brain area, was 4 cm in diameter. More than 70% of the AVM masses were excised in 11 of the patients, while under 50% was excised in the remaining patient. Complete excisions of the lesions were achieved in all 12 patients 7-10 days after endovascular embolization. No new major neurological deficits occurred. The results showed that the cerebral AVMs can be effectively operated on after endovascular embolization.