Diversity and Distribution of Methanogenic Community Between Two Typical Alpine Ecosystems on the Qinghai-Tibetan Plateau.

Alpine permafrost regions are important sources of biogenic CH4 and methanogens play an important role in the methane-producing process. The alpine permafrost on the Qinghai-Tibetan plateau comprises about one-sixth of China's land area, and there are various types of alpine ecosystems. However, the methanogenic communities in the typical alpine ecosystems are poorly understood. In this study, the active layers and permafrost layers of the natural ecosystem of alpine grassland (DZ2-1) and alpine swamp meadow (DZ2-5) were selected to investigate the diversity and abundance of methanogenic communities. Methanobacterium (63.65%) are overwhelmingly dominant in the active layer of the alpine grassland (DZ2-1A). ZC-I cluster (26.13%), RC-I cluster (19.56%), and Methanobacterium (15.02%) are the dominant groups in the permafrost layer of the alpine grassland (DZ2-1P). Methanosaeta (32.92%), Fen cluster (29.59%), Methanosarcina (16.33%), and Methanobacterium (13.95%) are the dominant groups in the active layer of the alpine swamp meadow (DZ2-5A), whereas the Fen cluster (50.85%), ZC-I cluster (27.63%), and RC-I cluster (14.15%) are relatively abundant in the permafrost layer of the alpine swamp meadow (DZ2-5P). qPCR data showed that the abundance of methanogens was higher in the natural ecosystem of alpine swamp meadow than in alpine grassland. We found that the community characteristics of methanogens were related to environmental factors. Pearson correlation analyses indicated that the relative abundance of Methanobacterium had a significantly positive correlation with hydrogen concentration (P < 0.01), while the relative abundances of Methanosaeta and Methanosarcina were positively correlated with acetate concentration (P < 0.05). This study will help us to understand the methanogenic communities and their surrounding environments in alpine ecosystems.

Comparative evaluation of three archaeal primer pairs for exploring archaeal communities in deep-sea sediments and permafrost soils.

16S rRNA gene profiling is a powerful method for characterizing microbial communities; however, no universal primer pair can target all bacteria and archaea, resulting in different primer pairs which may impact the diversity profile obtained. Here, we evaluated three pairs of high-throughput sequencing primers for characterizing archaeal communities from deep-sea sediments and permafrost soils. The results show that primer pair Arch519/Arch915 (V4-V5 regions) produced the highest alpha diversity estimates, followed by Arch349f/Arch806r (V3-V4 regions) and A751f/AU1204r (V5-V7 regions) in both sample types. The archaeal taxonomic compositions and the relative abundance estimates of archaeal communities are influenced by the primer pairs. Beta diversity of the archaeal community detected by the three primer pairs reveals that primer pairs Arch349f/Arch806r and Arch519f/Arch915r are biased toward detection of Halobacteriales, Methanobacteriales and MBG-E/Hydrothermarchaeota, whereas the primer pairs Arch519f/Arch915r and A751f/UA1204r are biased to detect MBG-B/Lokiarchaeota, and the primers pairs Arch349f/Arch806r and A751f/UA1204r are biased to detect Methanomicrobiales and Methanosarcinales. The data suggest that the alpha and beta diversities of archaeal communities as well as the community compositions are influenced by the primer pair choice. This finding provides researchers with valuable experimental insight for selection of appropriate archaeal primer pairs to characterize archaeal communities.

Shifts of methanogenic communities in response to permafrost thaw results in rising methane emissions and soil property changes.

Permafrost thaw can bring negative consequences in terms of ecosystems, resulting in permafrost collapse, waterlogging, thermokarst lake development, and species composition changes. Little is known about how permafrost thaw influences microbial community shifts and their activities. Here, we show that the dominant archaeal community shifts from Methanomicrobiales to Methanosarcinales in response to the permafrost thaw, and the increase in methane emission is found to be associated with the methanogenic archaea, which rapidly bloom with nearly tenfold increase in total number. The mcrA gene clone libraries analyses indicate that Methanocellales/Rice Cluster I was predominant both in the original permafrost and in the thawed permafrost. However, only species belonging to Methanosarcinales showed higher transcriptional activities in the thawed permafrost, indicating a shift of methanogens from hydrogenotrophic to partly acetoclastic methane-generating metabolic processes. In addition, data also show the soil texture and features change as a result of microbial reproduction and activity induced by this permafrost thaw. Those data indicate that microbial ecology under warming permafrost has potential impacts on ecosystem and methane emissions.

Comparative Analyses of Methanogenic and Methanotrophic Communities Between Two Different Water Regimes in Controlled Wetlands on the Qinghai-Tibetan Plateau, China.

Wetlands are an important methane (CH4) emission source. CH4 is mainly produced during the biogeochemical process, in which methanogens and methanotrophs both play important roles. However, little is known how these two microbial communities change under different water regimes. In this study, the diversity and abundance of methanogens and methanotrophs in wetlands on Qinghai-Tibetan Plateau with different water contents (a high water content site DZ2-14-3 and a low water content site DZ2-14-4) were studied by using phylogenetic analysis and quantitative PCR based on mcrA gene and pmoA gene. A total of 16 methanogenic operational taxonomic units (OTUs) and 9 methanotrophic OTUs are obtained. For methanogens, Fen cluster (58.0%) and Methanosaetaceae (20.3%) are the dominant groups in high moisture samples, whereas Methanosaetaceae (32.4%), Methanosarcinaceae (29.4%), and Methanobacteriaceae (22.1%) are prevalent in low moisture samples. Methylobacter (90.0%) of type I methanotrophs are overwhelmingly dominant in high moisture samples, while Methylocystis (53.3%) and Methylomonas (42.2%) belonging to types II and I methanotrophs are the predominant groups in low moisture samples. Furthermore, qPCR analysis revealed that the abundance of methanogens and methanotrophs were higher in high moisture samples than that in low moisture samples. Overall, this comparative study between wetlands controlled by two different water regimes on the Qinghai-Tibetan Plateau provides fundamental data for further research on microbial functions within extreme ecosystems.

Diversity and distribution of archaea community along a stratigraphic permafrost profile from Qinghai-Tibetan Plateau, China.

Accompanying the thawing permafrost expected to result from the climate change, microbial decomposition of the massive amounts of frozen organic carbon stored in permafrost is a potential emission source of greenhouse gases, possibly leading to positive feedbacks to the greenhouse effect. In this study, the community composition of archaea in stratigraphic soils from an alpine permafrost of Qinghai-Tibetan Plateau was investigated. Phylogenic analysis of 16S rRNA sequences revealed that the community was predominantly constituted by Crenarchaeota and Euryarchaeota. The active layer contained a proportion of Crenarchaeota at 51.2%, with the proportion of Euryarchaeota at 48.8%, whereas the permafrost contained 41.2% Crenarchaeota and 58.8% Euryarchaeota, based on 16S rRNA gene sequence analysis. OTU1 and OTU11, affiliated to Group 1.3b/MCG-A within Crenarchaeota and the unclassified group within Euryarchaeota, respectively, were widely distributed in all sediment layers. However, OTU5 affiliated to Group 1.3b/MCG-A was primarily distributed in the active layers. Sequence analysis of the DGGE bands from the 16S rRNAs of methanogenic archaea showed that the majority of methanogens belonged to Methanosarcinales and Methanomicrobiales affiliated to Euryarchaeota and the uncultured ZC-I cluster affiliated to Methanosarcinales distributed in all the depths along the permafrost profile, which indicated a dominant group of methanogens occurring in the cold ecosystems.

Finite element analysis of endoscopic cross-overtop decompression for single-segment lumbar spinal stenosis based on real clinical cases.

Introduction: For severe degenerative lumbar spinal stenosis (DLSS), the conventional percutaneous endoscopic translaminar decompression (PEID) has some limitations. The modified PEID, Cross-Overtop decompression, ensures sufficient decompression without excessive damage to the facet joints and posterior complex integrity. Objectives: To evaluate the biomechanical properties of Cross-Overtop and provide practical case validation for final decision-making in severe DLSS treatment. Methods: A finite element (FE) model of L4-L5 (M0) was established, and the validity was verified against prior studies. Endo-ULBD (M1), Endo-LOVE (M2), and Cross-Overtop (M3) models were derived from M0 using the experimental protocol. L4-L5 segments in each model were evaluated for the range of motion (ROM) and disc Von Mises stress extremum. The real clinical Cross-Overtop model was constructed based on clinical CT images, disregarding paraspinal muscle influence. Subsequent validation using actual FE analysis results enhances the credibility of the preceding virtual FE analysis. Results: Compared with M0, ROM in surgical models were less than 10°, and the growth rate of ROM ranged from 0.10% to 11.56%, while those of disc stress ranged from 0% to 15.75%. Compared with preoperative, the growth rate of ROM and disc stress were 2.66%-11.38% and 1.38%-9.51%, respectively. The ROM values in both virtual and actual models were less than 10°, verifying the affected segment stability after Cross-Overtop decompression. Conclusion: Cross-Overtop, designed for fully expanding the central canal and contralateral recess, maximizing the integrity of the facet joints and posterior complex, does no significant effect on the affected segmental biomechanics and can be recommended as an effective endoscopic treatment for severe DLSS.

Comparative Analysis of Non-Full and Full Endoscopic Spine Technique via Interlaminar Approach for the Treatment of Degenerative Lumbar Spinal Stenosis: A Retrospective, Single Institute, Propensity Score-Matched Study.

STUDY DESIGN: Retrospective study. OBJECTIVE: To compare the clinical efficacy of posterior lumbar laminectomy decompression under full endoscopic technique (Endo-LOVE) and percutaneous endoscopic medial foraminal decompression (PE-MFD) in the treatment of degenerative lumbar spinal stenosis (DLSS). METHODS: Between April 2017 and April 2018, 96 patients with DLSS underwent Endo-LOVE or PE-MFD, including 58 with Endo-LOVE and 38 with PE-MFD. After propensity score matching (PSM), patient characteristics, operation time, intraoperative fluoroscopy times, postoperative bedridden time, hospital stay and postoperative complications were recorded and compared. The clinical efficacy was evaluated according to Oswestry disability index (ODI), visual analogue scale (VAS), lumbar disease JOA and modified MacNab criteria. RESULTS: A total of 96 patients with DLSS were included in the study. After PSM, the 2 groups were comparable in patient demographic and baseline characteristics. The operation time and intraoperative fluoroscopy times in PE-MFD group were significantly more than those in Endo-LOVE group (P < .05). The operation time in PE-MFD group was significantly less than that in Endo-LOVE group (P < .05).The intraoperative fluoroscopy times in PE-MFD group were significantly more than that in Endo-LOVE group (P < .05). The ODI, VAS and lumbar disease JOA in the 2 groups were significantly improved comparing with those before operation (P < .05). According to the modified MacNab criteria, the excellent and good rates of the 2 groups were 93.5% in Endo-LOVE group and 87.1% in PE-MFD group (P > .05). CONCLUSION: Endo-LOVE and PE-MFD technique can both effectively treat DLSS, and the short-term follow-up results are positive. Endo-LOVE technique has the advantages of fast puncture positioning, less radiation exposure and wider indications. However, PE-MFD needs more radiation exposure and has the possibility of incomplete decompression for complex multiplanar spinal stenosis.

The effectiveness of postoperative exercise based on gait analysis compared with conventional exercise in patients with lumbar spinal stenosis: A randomized clinical trial.

BACKGROUND: Despite being used as a program of postoperative rehabilitation, few randomized controlled trials have compared the effectiveness of postoperative exercise based on gait analysis in patients with lumbar spinal stenosis (LSS). OBJECTIVE: To investigate the effectiveness of postoperative exercise based on gait analysis in patients with LSS and to compare it with the effectiveness of conventional exercise. METHODS: This was a double-blind, randomized clinical trial. Sixty-eight participants with LSS were randomly assigned to one of two groups. After receiving a standardized surgical procedure, the observation group received exercises based on 3-D gait analysis, and the control group received empirical physiotherapy containing 4 basic interventions. Both groups took a one-hour session twice daily for 2 weeks. The Oswestry Disability Index (ODI) scale and the Visual Analog Scale (VAS) were measured before and 2 weeks and 6 months after intervention. The gait indicators were measured before and 6 months after intervention. RESULTS: At baseline, there were no significant differences in the ODI, VAS or absolute symmetry index (ASI) of the gait variables between the observation group and the control group. However, at 6 months, pain intensity, walking, standing, social life and summary scores of ODI and VAS of the leg demonstrated significant differences (p< 0.05, respectively) between groups, and the observation group had greater reductions in ASI of stride length, hip flexion, knee flexion and ankle dorsiflexion compared with the control group (p< 0.05, respectively). CONCLUSIONS: The postoperative rehabilitation scheme based on gait analysis resulted in significant short- to medium-term improvements in pain intensity, walking, standing, social life and the summary score of ODI, VAS of leg and symmetry of stride length, hip flexion, knee flexion and ankle dorsiflexion compared with empirical exercise in patients with LSS.

Response of methanogenic community and their activity to temperature rise in alpine swamp meadow at different water level of the permafrost wetland on Qinghai-Tibet Plateau.

Wetlands are an important source of atmospheric methane (CH4) and are sensitive to global climate change. Alpine swamp meadows, accounting for ~50% of the natural wetlands on the Qinghai-Tibet Plateau, were considered one of the most important ecosystems. Methanogens are important functional microbes that perform the methane producing process. However, the response of methanogenic community and the main pathways of CH4 production to temperature rise remains unknown in alpine swamp meadow at different water level in permafrost wetlands. In this study, we investigated the response of soil CH4 production and the shift of methanogenic community to temperature rise in the alpine swamp meadow soil samples with different water levels collected from the Qinghai-Tibet Plateau through anaerobic incubation at 5°C, 15°C and 25°C. The results showed that the CH4 contents increased with increasing incubation temperature, and were 5-10 times higher at the high water level sites (GHM1 and GHM2) than that at the low water level site (GHM3). For the high water level sites (GHM1 and GHM2), the change of incubation temperatures had little effect on the methanogenic community structure. Methanotrichaceae (32.44-65.46%), Methanobacteriaceae (19.30-58.86%) and Methanosarcinaceae (3.22-21.24%) were the dominant methanogen groups, with the abundance of Methanotrichaceae and Methanosarcinaceae having a significant positive correlation with CH4 production (p < 0.01). For the low water level site (GHM3), the methanogenic community structure changed greatly at 25°C. The Methanobacteriaceae (59.65-77.33%) was the dominant methanogen group at 5°C and 15°C; In contrast, the Methanosarcinaceae (69.29%) dominated at 25°C, and its abundance showed a significant positive correlation with CH4 production (p < 0.05). Collectively, these findings enhance the understanding of methanogenic community structures and CH4 production in permafrost wetlands with different water levels during the warming process.

[Effect of acupotomy on the fat infiltration degree of lumbar multifidus muscle in patients with lumbar disc herniation after percutaneous transforaminal endoscopic discectomy].

OBJECTIVE: To observe the effect of acupotomy on the fat infiltration degree of lumbar multifidus muscle (LMM) in patients with lumbar disc herniation after percutaneous transforaminal endoscopic discectomy (PTED). METHODS: A total of 104 patients with lumbar disc herniation treated with PTED were randomly divided into an observation group (52 cases, 3 cases dropped off) and a control group (52 cases, 4 cases dropped off). Patients of both groups received rehabilitation training of two weeks 48 h after PTED treatment. The observation group was treated with acupotomy (L3-L5 Jiaji [EX-B 2]) once within 24 h after PTED. In the two groups, the fat infiltration cross sectional area (CSA) of LMM was compared before and 6 months after PTED, the visual analogue scale (VAS) score and Oswestry disability index (ODI) score were observed before and 1, 6 months after PTED. The correlation between fat infiltration CSA of LMM in each segment and VAS score was analyzed. RESULTS: Six months after PTED, the fat infiltration CSA of LMM in L4/L5 and the total L3-S1 segments of the observation group was lower than that before PTED (P<0.05), and the fat infiltration CSA of LMM in L4/L5 of the observation group was lower than the control group (P<0.01). One month after PTED, the ODI and VAS scores of the two groups were lower than those before PTED (P<0.01), and those in the observation group were lower than the control group (P<0.05). Six months after PTED, the ODI and VAS scores of the two groups were lower than those before PTED and 1 month after PTED (P<0.01), and those in the observation group were lower than the control group (P<0.01). There was a positive correlation between the fat infiltration CSA of LMM in the total L3-S1 segments and VAS scores in the two groups before PTED (r = 0.64, P<0.01). Six months after PTED, there was no correlation between the fat infiltration CSA of LMM in each segment and VAS scores in the two groups (P>0.05). CONCLUSION: Acupotomy can improve the fat infiltration degree of LMM, pain symptoms and activities of daily living in patients with lumbar disc herniation after PTED.

[Platelet rich plasma intra-articular and extra-articular injection for the treatment of knee osteoarthritis].

OBJECTIVE: To observe clinical effects of platelet-rich plasma (PRP) intra-articular and extra-articular injection for patients with knee osteoarthritis (KOA), and analyze its safety and clinical efficacy. METHODS: From January to December 2017, 48 patients with KOA were randomly divided into observation group and control group, 24 cases in each group. The observation group was treated with intra-articular injection of PRP (2 ml) and extra-articular injection of PRP (2 ml), once a week, for three times, including 8 males and 16 females with an average of (58.04±7.87) years old ranging from 43 to 68 years old, the courses of disease ranged from 1 to 8 years with an average of (4.69±1.96) years, the body mass index (BMI) was (24.53±5.26) kg/m 2 . The control group was treated with intra-articular injection of sodium hyaluronate (20 mg), extra-articular injection of analgesic drug (2 ml for one point), once a week, for three times, including 7 males and 17 females with an average of (60.54±8.93) years old ranging from 47 to 72 years old, the courses of disease ranged from 1.5 to 9 years with an average of (5.27±1.68) years, BMI was (23.47±4.62) kg/m 2 . VAS score and Lysholm score before operation and the 1st, 6th month after treatment were compared between two groups. RESULTS: All patients were followed up at least 6 months without occurrence serious adverse reactions or complications. VAS score in observation group and control group before treatment and 1st, 6th month after treatment were 7.35±1.47, 4.15±1.52, 2.26±1.02 and 7.51±1.39, 3.84±1.76, 3.66±1.18, respectively; VAS score in obsevation group was lower than that of control group at 6 months after treatment. Lysholm score in observation group and control group before treatment and 1st, 6th month after treatment were 55.21±5.78, 79.16±7.25, 85.45±6.87 and 54.65± 6.40, 77.58±6.94, 82.34±7.12. There were significant differences in Lysholm score before and after injection between two groups (P<0.05) . There was no significant difference in Lysholm score between two groups at 1 month after treatment (P>0.05), while Lysholm score in observation group was better than that of control group at 6 months after treatment (P<0.05) . CONCLUSION: Intra-articular and extra-articular injection of PRP could relieve pain symptoms and improve function of knee joint with higher safety, although the short-term effect is not significantly different from traditional treatment, its medium-long-term effect is stable. It is a safe and effective method for the treatment of knee osteoarthritis.

"Tube in tube" interlaminar endoscopic decompression for the treatment of lumbar spinal stenosis: Technique notes and preliminary clinical outcomes of case series.

To describe the Tube in Tube interlaminar endoscopic decompression method and investigate its efficacy and safety in treating lumbar spinal stenosis (LSS).Utilizing the advantages of the micro-endoscopic decompression (MED) operation channel tube, we used a water-medium spinal endoscopy to perform trans-interlaminar canal decompression, that is, the "Tube in Tube" technique. A retrospective study was performed on 35 patients with LSS who were treated with the Tube in Tube technique. All patients were followed up to 12 months postoperatively. Visual analog scale (VAS), Japanese Orthopaedic Association (JOA) score, and Oswestry Disability Index (ODI) were collected preoperatively and at 3, 6, and 12 months postoperatively. Short-form (36) health survey (SF-36) score was used to examine the general health-related quality of life (HRQoL) of patients preoperatively and at 3 and 12 months postoperatively. Modified Macnab criteria were used to examine the clinical outcomes at 3 and 12 months post-surgery.The clinical outcomes were satisfactory, with an improvement in all scoring systems. The VAS, JOA, and ODI scores improved from 6.46 ±â€Š1.85, 12.03 ±â€Š4.96, and 42.17 ±â€Š12.22 preoperatively to 2.20 ±â€Š1.14, 21.40 ±â€Š5.86, and 13.14 ±â€Š7.52 at 12 months postoperatively, respectively (P < .001). The Macnab excellent or good rates reached 65.7% and 77.1% at the 3 and 12 months follow-ups. No severe complications occurred.The Tube in Tube technique had a positive clinical outcome in LSS patients and is safe, reliable, and efficacious. However, a larger number of cases and a multi-center research design will be needed further develop the technique.Level of Evidence: IV.

Microbial diversity of two cold seep systems in gas hydrate-bearing sediments in the South China Sea.

Cold seep is a unique habitat for microorganisms in deep marine sediments, and microbial communities and biogeochemical processes are still poorly understood, especially in relation to hydrate-bearing geo-systems. In this study, two cold seep systems were sampled and microbial diversity was studied at Site GMGS2-08 in the northern part of the South China Sea (SCS) during the GMGS2 gas hydrate expedition. The current cold seep system was composed of a sulfate methane transition zone (SMTZ) and an upper gas hydrate zone (UGHZ). The buried cold seep system was composed of an authigenic carbonate zone (ACZ) and a lower gas hydrate zone (LGHZ). These drill core samples provided an excellent opportunity for analyzing the microbial abundance and diversity based on quantitative polymerase chain reaction (qPCR) and high-throughput 16S rRNA gene sequencing. Compared to previous studies, the high relative abundance of ANME-1b, a clade of anaerobic methanotrophic archaea (ANME), may perform anaerobic oxidation of methane (AOM) in collaboration with ANME-2c and Desulfobacteraceae in the SMTZ, and the high relative abundances of Hadesarchaea, ANME-1b archaea and Aerophobetes bacteria were found in the gas hydrate zone (GHZ) at Site GMGS2-08. ANME-1b, detected in the GHZ, might mainly mediate the AOM process, and the process might occur in a wide depth range within the LGHZ. Moreover, bacterial communities were significantly different between the GHZ and non-GHZ sediments. In the ACZ, archaeal communities were different between the two samples from the upper and the lower layers, while bacterial communities shared similarities. Overall, this new record of cold seep microbial diversity at Site GMGS2-08 showed the complexity of the interaction between biogeochemical reactions and environmental conditions.

Reliability and validity of Simplified Chinese version of Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) questionnaire: cross-cultural adaptation and validation.

OBJECTIVE: To translate and cross-culturally adapt Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) Questionnaire into a Simplified Chinese version (QuickDASH-C), and evaluate the reliability and validity of the QuickDASH-C in patients with upper limb disorders. METHODS: Cross-cultural adaptation was performed according to the internationally recognized guidelines of American Academy of Orthopedic Surgeons Outcome Committee. A total of 150 participants were recruited in this study. Internal consistency was estimated using Cronbach's alpha. Intra-class correlation coefficient (ICC) was used to determine test-retest reliability. Construct validity was analyzed by evaluating the correlations between QuickDASH-C and Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire and visual analogue scale (VAS) as well as the short form (36) health survey (SF-36). RESULTS: The original version of the QuickDASH was well cross-culturally adapted and translated into Simplified Chinese. QuickDASH-C was indicated to have excellent reliability (Cronbach's alpha = 0.818, ICC = 0.907). QuickDASH-C correlated almost perfectly to DASH (r = 0.820, p < 0.001). Moderate to substantial correlations between QuickDASH-C and VAS (r = 0.463, p < 0.001), as well as physical function (r = - 0.630, p < 0.001), role physical (r = - 0.471, p < 0.001), bodily pain (r = - 0.563, p < 0.001) and general health (r = - 0.414, p < 0.001) subscales of SF-36, were observed. CONCLUSION: QuickDASH-C was demonstrated to have excellent acceptability, reliability, and validity in patients with upper limb disorders, which could be recommended for patients in mainland China. KEY POINTS: • This study translated and cross-culturally adapted Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) questionnaire into a Simplified Chinese version. • The reliability and validity of Simplified Chinese version of QuickDASH were good in evaluating patients with upper limb disorders.

[Percutaneously full endoscopic decompressive laminectomy with precise localization for the treatment of lumbar spinal stenosis].

OBJECTIVE: To explore the feasibility of full endoscopic fenestration (FE-FE) via interlaminar approach for the treatment of lumbar spinal stenosis (LSS), and meanwhile, to analyze the related practicability and clinical outcome. METHODS: Referring to the traditional laminectomy and decompression, the lumbar spinal canal decompression was performed by using the water-medium spinal endoscopy (named FE-FE technique). Thirty-seven patients with LSS treated by FE-FE technique were retrospectively analyzed. There were 19 males and 18 females, aged from 55 to 83 years old with an average of (67.1±18.9) years. Visual analogue scale(VAS), Japanese Orthopaedic Association Scores(JOA), Oswestry Disability Index (ODI) and 36-Item Short-Form Health Survey (SF-36) were recorded. The patient's conscious pain and recovery of neurological function were observed, and the clinical efficacy was evaluated according to the improvement rate of JOA score. RESULTS: All 37 patients were followed up for 8 to 24 months with an average of (13.7±6.1) months. The postoperative follow-up and clinical evaluation for conscious pain and neurological function recovery showed that VAS, JOA, ODI and SF-36 scores were significantly improved compared with those before surgery(P<0.05). According to the improvement rate of JOA score to evaluate the clinical effects, at 6 months after opertion, the results were excellent in 17 cases, good in 13 cases, fair in 5 cases, and poor in 2 cases;and the last follow-up, the results were excellent in 19 cases, good in 13 cases, fair in 4 cases, and poor in 1 case. Postoperative imaging showed significant expansion of spine canal volume, and the followed-up clinical symptoms were improved satisfactorily, with the relief of lumbago and leg pain, improvement of daily life quality, and increased adaptability to social activities and no serious complications. CONCLUSIONS: Precise localization is the key to complete the canal decompression under full endoscopic surgery. FE-FE technique can effectively enlarge the narrow lumbar canal with less trauma, positive efficacy, safety and reliability. FE-FE has a broad application prospect though large cases and multi-center studies need to be further carried out.

Biomineralization processes of calcite induced by bacteria isolated from marine sediments.

Biomineralization is a known natural phenomenon associated with a wide range of bacterial species. Bacterial-induced calcium carbonate precipitation by marine isolates was investigated in this study. Three genera of ureolytic bacteria, Sporosarcina sp., Bacillus sp. and Brevundimonas sp. were observed to precipitate calcium carbonate minerals. Of these species, Sporosarcina sp. dominated the cultured isolates. B. lentus CP28 generated higher urease activity and facilitated more efficient precipitation of calcium carbonate at 3.24 ± 0.25 × 10(-4) mg/cell. X-ray diffraction indicated that the dominant calcium carbonate phase was calcite. Scanning electron microscopy showed that morphologies of the minerals were dominated by cubic, rhombic and polygonal plate-like crystals. The dynamic process of microbial calcium carbonate precipitation revealed that B. lentus CP28 precipitated calcite crystals through the enzymatic hydrolysis of urea, and that when ammonium ion concentrations reached 746 mM and the pH reached 9.6, that favored calcite precipitation at a higher level of 96 mg/L. The results of this research provide evidence that a variety of marine bacteria can induce calcium carbonate precipitation, and may influence the marine carbonate cycle in natural environments.

Diversity of culturable moderately halophilic bacteria producing extracellular hydrolytic enzymes from marine sediments / Diversidade de bactérias cultiváveis moderadamente halofílicas que produzem enzimas hidrolíticas extracelulares de sedimentos marinhos

A total of 114 moderately halophilic bacteria were isolated from marine sediment environments. The isolates are belonged to 23 species based on the 16S rRNA sequence analysis. 63, 52, 47, 57, 74, 15 and 4 isolates are able to produce protease, amylase, lipase, pectinase, pulluanase, xylanase, cellulase, respectively. Combined hydrolytic enzyme activity analysis show that 15 strains present 1 hydrolytic activity, 32 strains present 2 hydrolytic activities, 21 strains present 3 hydrolytic activities, 26 strains present 4 hydrolytic activities, 11 strains present 5 hydrolytic activities and 2 strains present 6 hydrolytic activities. Hydrolase activities are widely distributed in a variety of species. The highest rates for production of protease, amylase, lipase, pectinase, pullanase, xylanase and cellulase were observed in species of B. baekryungensis, Hallobacillus sp., B. pumilus, B. megaterium or P. chungwhensis, B. amyloliquefaciens, B. pumilus, B. baekryungensis, respectively. However, the higher activities of protease, pectinase and pulluanase are frequently produced by the species of Halomonas sp. B. amyloliquefaciens or P. chungwhensis, and Vibrio sp. respectively. This investigation show that the diversity of halophilic bacteria from marine sediments could serve as a potential source of hydrolytic enzymes for industrial applications. (AU)

Um total de 114 bactérias moderadamente halofílicas foram isoladas de ambientes de sedimentos marinhos. Os isolados pertencem a 23 espécies com base na análise da sequência 16S rRNA. 63, 52, 47, 57, 74, 15 e 4 isolados são capazes de produzir protease, amilase, lipase, pectinase, pululanase, xilanase, celulase, respectivamente. A análise da atividade enzimática hidrolítica combinada mostra que 15 cepas apresentam 1 atividade hidrolítica, 32 cepas apresentam 2 atividades hidrolíticas, 21 cepas apresentam 3 atividades hidrolíticas, 26 cepas apresentam 4 atividades hidrolíticas, 11 cepas apresentam 5 atividades hidrolíticas e 2 cepas apresentam 6 atividades hidrolíticas. Atividades de hidrolase são amplamente distribuídas em uma variedade de espécies. As maiores taxas de produção de protease, amilase, lipase, pectinase, pululanase, xilanase e celulase foram observadas em espécies de B. baekryungensis, Hallobacillus sp., B. pumilus, B. megaterium ou P. chungwhensis, B. amyloliquefaciens, B. pumilus, B. baekryungensis, respectivamente. No entanto, as atividades mais elevadas de protease, pectinase e pululanase são freqüentemente produzidas pelas espécies de Halomonas sp. B. amyloliquefaciens ou P. chungwhensis e Vibrio sp. respectivamente. Esta investigação mostra que a diversidade de bactérias halofílicas de sedimentos marinhos pode servir como uma fonte potencial de enzimas hidrolíticas para aplicações industriais. (AU)

Biomineralization processes of calcite induced by bacteria isolated from marine sediments

Biomineralization is a known natural phenomenon associated with a wide range of bacterial species. Bacterial-induced calcium carbonate precipitation by marine isolates was investigated in this study. Three genera of ureolytic bacteria, Sporosarcina sp., Bacillus sp. and Brevundimonas sp. were observed to precipitate calcium carbonate minerals. Of these species, Sporosarcina sp. dominated the cultured isolates. B. lentus CP28 generated higher urease activity and facilitated more efficient precipitation of calcium carbonate at 3.24 ± 0.25 × 10−4 mg/cell. X-ray diffraction indicated that the dominant calcium carbonate phase was calcite. Scanning electron microscopy showed that morphologies of the minerals were dominated by cubic, rhombic and polygonal plate-like crystals. The dynamic process of microbial calcium carbonate precipitation revealed that B. lentus CP28 precipitated calcite crystals through the enzymatic hydrolysis of urea, and that when ammonium ion concentrations reached 746 mM and the pH reached 9.6, that favored calcite precipitation at a higher level of 96 mg/L. The results of this research provide evidence that a variety of marine bacteria can induce calcium carbonate precipitation, and may influence the marine carbonate cycle in natural environments.