Novel database for accA gene revealed a vertical variability pattern of autotrophic carbon fixation potential of ammonia oxidizing archaea in a permeable subterranean estuary.

The autotrophic carbon fixation pathway of ammonia-oxidizing archaea (AOA) was the 3-hydroxypropionate/4-hydroxybutyrate (3-HP/4-HB) cycle, of which the acetyl-CoA carboxylase α-submit (accA) gene is widely recognized as the indicator. To date, there is no reference database or suitable cut-off value for operational taxonomic unit (OTU) clustering to analyze the diversity of AOA based on the accA gene. In this study, a reference database with 489 sequences was constructed, all the accA gene sequences was obtained from the AOA enrichment culture, pure culture and environmental samples. Additionally, the 79% was determined as the cut-off value for OTU clustering by comparing the similarity between the accA gene and the 16S rRNA gene. The developed method was verified by analyzing samples from the subterranean estuary and a vertical variation pattern of autotrophic carbon fixation potential of AOA was revealed. This study provided an effective method to analyze the diversity and autotrophic carbon fixation potential of AOA based on accA gene.

[Tibialis anterior allograft versus hamstring tendon autograft for anterior cruciate ligament reconstruction:long-term clinical outcomes].

OBJECTIVE: To compare the clinical outcomes of arthroscopic anterior cruciate ligament (ACL) reconstruction (ACLR) with a tibialis anterior allograft (TAA)versus hamstring tendon autograft (HTA) after 10 years follow-up. METHODS: A clinical data of 107 patients who underwent arthroscopic ACLR with a single bundle tendon between March 2007 and March 2010 was retrospectively analyzed. Among the patients, 48 patients were reconstructed with a tibialis anterior allograft (TAA group), including 26 males and 22 females, ranging in age from 16 to 38 years, with a mean of 27.2±6.2 years;59 patients were reconstructed with a hamstring tendon autograft (HTA group), including 31 males and 28 females, ranging in age from 16 to 40 years, with a mean of 28.0±7.6 years. The preoperative tibial anterior displacement and knee joint function, as well as knee joint stability, tibial anterior displacement and knee joint function at 10 years after operation were observed. Lachman test was used to evaluate the forward joint stability and pivot shift test to evaluate the rotational stability of the knee;KT-2000 side-to-side difference (SSD) was used to measure tibial anterior displacement;International Knee Documentation Committee(IKDC) score and Lysholm score were used to evaluate knee function. RESULTS: The incisions of both groups were healed by first intention, and no early complications occurred after operation. All patients were followed-up 10 to 13 years, the mean time was 11.7 years. There was no graft failure were found during the follow up period. The KT-2000 SSD of the TAA group and the HTA group at ten years after operation were 1.9±0.7 and 1.8±0.6 respectively, which were significantly improved than 8.8±0.9 and 8.6±1.0 preoperatively(P<0.05), but there were no significant difference between the two groups(P>0.05). The total Lysholm score of the TAA group and the HTA group at ten years after operation were 90.4±4.4 and 90.7±3.4 respectively, which were significantly improved than 51.4±13.3 and 51.2±14.6 preoperatively(P<0.05), but there were no significant difference between the two groups(P>0.05). The total IKDC score of the TAA group and the HTA group at ten years after operation were 91.5±4.1 and 90.9±3.2 respectively, which were significantly improved than 45.8±12.2 and 47.0±14.5 preoperatively(P<0.05), but there were no significant difference between the two groups(P>0.05). No significant difference were found between the two groups in Lachman test and pivot shift test at 10 years after operation (P>0.05). CONCLUSION: The TAA and HTA have equal long term effect in ACL reconstruction, doctors and patients can choose the graft according to the actual situation.