Re-watering solution facilitates seed germination and seedling growth of Carex schmidtii: Implication for species re-introduction in degraded semi-arid wetlands.

Water deficiency threatens the health and function of wetlands in semi-arid areas. Optimum re-watering is an effective method for close-to-natural restoration to mitigate wetland degradation. Although the ecological importance of optimal re-watering as a nature-based solution for promoting wetland plant growth has been widely recognized, the response mechanisms of seed germination and seedling growth to re-watering are still poorly understood despite their decisive impact on plant life history. To fill this gap, this study compared the characteristics of seed germination and seedling growth in Carex schmidtii under initial water content with three levels (30%, 50%, and 70%) and five re-watering treatments (maintained at constant water content and re-watering to 100% on 7th, 14th, 21st, and 28th day). Moreover, the degree of reserve mobilization during four germination stages (seed suckering, sprouting, 20% germination, and seedling growth) was investigated. The results showed that water deficiency and re-watering treatments significantly affected C. schmidtii seed germination, seedling growth, and reserve mobilization. Compared with the other treatments, 50% moisture content and re-watering to 100% on the 14th day (50%-RT3) treatment significantly improved germination traits (germination rate, daily germination rate, germination index, and vigor index) and seedling growth characteristics (shoot length, root length, shoot biomass, root biomass, and total biomass). Furthermore, the degree of mobilization of starch, soluble protein, fat, and soluble sugar accumulation in C. schmidtii seeds under 50%-RT3 was higher than that in the other treatments. The structural equation model showed that the characteristics of seed germination and seedling growth of C. schmidtii were directly related to water deficiency and re-watering treatments, whereas reserve mobilization indirectly affected seed germination and seedling growth. These findings demonstrated that water deficiency and re-watering treatments have a crucial regulatory effect on seed germination and seedling growth of wetland plant species through a dual mechanism. This study provides information for the formulation of an optimum re-watering strategy for wetland vegetation restoration in semi-arid areas of the world.

Hydrological and biogeochemical processes controlling riparian groundwater quantity and quality during riverbank filtration.

Groundwater exploitation in a riparian zone causes water infiltration from the river into the aquifer. Owing to adsorption and redox reactions along the flow path, the quality of water flowing from the river to groundwater wells is variably altered. The riverbed composition often involves spatiotemporal differences due to frequent changes in hydrological conditions. These changes create uncertainties in the transport and removal of solutes in the river water. In this study, the hydrodynamic field associated with riparian groundwater, changes in the structure of riverbed sediments caused by erosion and deposition, fluctuations in surface water and groundwater levels, and the removal efficiency of pollutants from groundwater through pumping were investigated. This involved in situ monitoring and sample testing of the composition of the river water, riverbed sediments, riverbed pore water, and groundwater during dry and wet seasons. Implementation of field in situ column experiments and molecular biology evidences were conducive to identifying the main biogeochemical processes occurring in the riverbed. The findings indicated that riparian groundwater exploitation alters the natural groundwater flow field, while fine sand deposition and microbial adsorption can reduce river recharge to aquifers by diminishing riverbed hydraulic conductivity. Shallow sediments within 1 m depth mainly involve NO3- reduction and E. coli adsorption. Reductive dissolution of Mn dominates in the deeper sediments. Additionally, reductive dissolution of Fe and dissimilatory nitrate reduction to ammonium (DNRA) drive high Fe2+ and NH4+ concentrations in groundwater. The findings can improve the management of riparian groundwater and aid in the optimization of a plan for its exploitation.

Experiments and simulation of co-migration of copper-resistant microorganisms and copper ions in saturated porous media.

Heavy metal (HV) pollutants may migrate to the groundwater environment through leaching, causing groundwater pollution. Compared with surface water pollution, groundwater pollution is complex and hidden. Existing methods for treating HV pollution in the vadose zone have had limited application owing to various problems. In recent years, microorganisms have been used in the field of pollution control and remediation owing to their outstanding adsorption and degradation properties and low cost, but their environmental safety and behavior in porous media are still poorly understood. This study aimed to investigate the migration behavior and mechanisms of copper ions in saturated porous media under the action of copper-resistant microorganisms and to establish a corresponding numerical model to simulate the results. The key parameters of adsorption and migration were determined through batch adsorption and soil column experiments. A one-dimensional soil column was used to conduct a co-migration experiment using copper-resistant microorganisms and Cu2+ in water-saturated quartz sand, and a co-migration mathematical model was constructed. It was found that the existence of microorganisms had an inhibitory effect on the migration of Cu2+ in quartz sand, and Cu2+ promoted the migration of microorganisms, reduced their adsorption, and increased their concentration in the column experiment effluent. The selected solute transport mathematical model had a good fitting effect on the breakthrough curves of copper ion and copper-resistant microorganisms during their co-migration. The results can provide parameters and a theoretical basis for the risk assessment and prevention of HV pollution in the saturated zone or aquifers.

Water quality attribution and simulation of non-point source pollution load flux in the Hulan River basin.

Surface water is the main source of irrigation and drinking water for rural communities by the Hulan River basin, an important grain-producing region in northeastern China. Understanding the spatial and temporal distribution of water quality and its driving forces is critical for sustainable development and the protection of water resources in the basin. Following sample collection and testing, the spatial distribution and driving forces of water quality were investigated using cluster analysis, hydrochemical feature partitioning, and Gibbs diagrams. The results demonstrated that the surface waters of the Hulan River Basin tend to be medium-weakly alkaline with a low degree of mineralization and water-rock interaction. Changes in topography and land use, confluence, application of pesticides and fertilizers, and the development of tourism were found to be important driving forces affecting the water quality of the basin. Non-point source pollution load fluxes of nitrogen (N) and phosphorus (P) were simulated using the Soil Water and Assessment Tool. The simulation demonstrated that the non-point source pollution loading is low upstream and increases downstream. The distributions of N and P loading varied throughout the basin. The findings of this study provide information regarding the spatial distribution of water quality in the region and present a scientific basis for future pollution control.

A novel 3D printed cage with microporous structure and in vivo fusion function.

In this study, a novel 3D printed porous titanium cage (3D printed cage) with interconnected pores inside was designed and manufactured. Observations by scanning electron microscopy showed that the inside of the 3D printed cage had an octahedral porous structure, with the pores uniform in size and connected to each other. The mechanical properties analysis found that the Young's modulus and compressive strength of the porous structure were close to those of the bone structure, and the overall stiffness was slightly higher than that of the polyether ether ketone (PEEK) material, but was significantly lower than that of the titanium alloy solid module. Animal experiments indicated that the new 3D printed cage was equivalent to PEEK cage in fusion time. At 3 months, the new bone grew into the cage through the pores of the new 3D printed cage surface, which had a high bone contact rate. These results demonstrate that the 3D printed porous titanium cage has good biocompatibility and osseointegration, and has a potential clinical value as bone implants. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2019.

An adaptive Kriging surrogate method for efficient joint estimation of hydraulic and biochemical parameters in reactive transport modeling.

Groundwater reactive transport models that consider the coupling of hydraulic and biochemical processes are vital tools for predicting the fate of groundwater contaminants and effective groundwater management. The models involve a large number of parameters whose specification greatly affects the model performance. Thus model parameters calibration is crucial to its successful application. The Bayesian inference framework implemented by Markov chain Monte Carlo (MCMC) sampling provides a comprehensive framework to estimate the model parameters. However, its application is hampered by the large computational requirements caused by repeated evaluations of the model in MCMC sampling. This study develops an adaptive Kriging-based MCMC method to overcome the bottleneck of Bayesian inference by replacing the simulation model with a computationally inexpensive Kriging surrogate model. In the adaptive Kriging-based MCMC method, instead of constructing a globally accurate surrogate of the simulation model, we sequentially build a locally accurate surrogate with an iterative refinement to the high probability regions. The performance of the proposed method is demonstrated using a synthetic groundwater reactive transport model for describing sequential Kinetic degradation of Tetrachloroethene (PCE), whose hydraulic and biochemical parameters are jointly estimated. The results suggest that the adaptive Kriging-based MCMC method is able to achieve an accurate Bayesian inference with a hundredfold reduction in the computational cost compared to the conventional MCMC method.

Biogeochemical zonation of sulfur during the discharge of groundwater to lake in desert plateau (Dakebo Lake, NW China).

As one of the important elements of controlling the redox system within the hyporheic and hypolentic zone, sulfur is involved in a series of complex biogeochemical processes such as carbon cycle, water acidification, formation of iron and manganese minerals, redox processes of trace metal elements and a series of important ecological processes. Previous studies on biogeochemistry of the hyporheic and hypolentic zones mostly concentrated on nutrients of nitrogen and phosphorus, heavy metals and other pollutants. Systematic study of biogeochemical behavior of sulfur and its main controlling factors within the lake hypolentic zone is very urgent and important. In this paper, a typical desert plateau lake, Dakebo Lake in northwestern China, was taken for example within which redox zonation and biogeochemical characteristics of sulfur affected by hydrodynamic conditions were studied based on not only traditional hydrochemical analysis, but also environmental isotope evidence. In the lake hypolentic zone of the study area, due to the different hydrodynamic conditions, vertical profile of sulfur species and environmental parameters differ at the two sites of the lake (western side and center). Reduction of sulfate, deposition and oxidation of sulfide, dissolution and precipitation of sulfur-bearing minerals occurred are responded well to Eh, dissolved oxygen, pH, organic carbon and microorganism according to which the lake hypolentic zone can be divided into reduced zone containing H2S, reduced zone containing no H2S, transition zone and oxidized zone. The results of this study provide valuable insights for understanding sulfur conversion processes and sulfur biogeochemical zonation within a lake hypolentic zone in an extreme plateau arid environment and for protecting the lake-wetland ecosystem in arid and semiarid regions.

How to Calculate the Exact Angle for Two-level Osteotomy in Ankylosing Spondylitis?

STUDY DESIGN: A prospective case series study. OBJECTIVE: To describe and assess a two-level osteotomy method for the management of severe thoracolumbar kyphosis (TLK) in patients with ankylosing spondylitis (AS). SUMMARY OF BACKGROUND DATA: To achieve better postoperative outcomes in these patients, a sophisticated preoperative surgical plan is required. Most deformities are managed using a one-level osteotomy and a two-level osteotomy is seldomly reported. Till date, no study has described a two-level osteotomy for these cases. METHODS: From January 2011 to December 2012, 10 consecutive patients with ankylosing spondylitis who underwent two-level spinal osteotomy were studied. Pre- and postoperative full-length free-standing radiographs, including the whole spine and pelvis, were available for all patients. Pre- and postoperative radiological parameters, including T5-S1 Cobb angles, TLK, lumbar lordosis, pelvic incidence, pelvic tilt, sacral slope, and sagittal vertical axis were measured. Health related quality of life , including Oswestry Disability Index and Scoliosis Research Society-22 surveys were administered before surgery and at 1-year follow up. RESULTS: The preoperative and postoperative T5-S1 Cobb angles was 51.3° and -7.1°, respectively (P < 0.001). All patients demonstrated changes in postoperative radiographic parameters including decreased pelvic tilt (from 37.1° to 14.3°, P < 0.001), TLK (from 36.9° to 12.6°, P < 0.001), and sagittal vertical axis (from 21.4 cm to 7.1 cm, P < 0.001), increased lumbar lordosis (from -5.1° to -47.1°, P < 0.001), sacral slope (from 13.4° to 37.7°, P < 0.001), but no significant change in pelvic incidence. Health related quality of life scores at 1-year follow up were significantly improved compared to those before surgery. CONCLUSION: This calculation of two-level osteotomy provides an accurate and reproducible method for ankylosing spondylitis correction. By which, we can obtain satisfactory radiological parameters and clinical outcomes. LEVEL OF EVIDENCE: 4.

Optimal chin-brow vertical angle for sagittal visual fields in ankylosing spondylitis kyphosis.

PURPOSE: Chin-brow vertical angle (CBVA) is very important in correction of thoracolumbar kyphotic deformity in ankylosing spondylitis (AS), especially for the patients with cervical ankylosis. In previous study, Suk et al. stated that the patients with CBVA between -10° and 10° had better horizontal gaze. Unfortunately, in our clinical practice, we found the patients with CBVA between -10° and 10° after surgery usually complained of difficulty in cooking, cleaning, desk working and the like, although they had excellent horizontal gaze. In other words, for the patients with cervical ankylosis, good horizontal gaze existed together with poor downward gaze. Then, which condition do the patients prefer? Is there a compromise solution that makes a better quality life possible for the patients? In this research, we studied AS patients with cervical ankylosis, aiming to investigate the optimal CBVA for deformity correction. METHODS: 25 AS thoracolumbar kyphotic patients with cervical ankylosis were studied, whose function and expectation of visual field related to life quality were assessed by questionnaire before and after surgery. Pre- and post-operative CBVA were obtained on lateral photos of the patients with free-standing posture, and 50 cases of CBVA were included, which were divided into six groups according to the angle irrespective of surgery (Group A, CBVA <0°; Group B, 0° ≤ CBVA < 10°; Group C, 10° ≤ CBVA < 20°; Group D, 20° ≤ CBVA < 30°; Group E, 30° ≤ CBVA < 40°; Group F, CBVA ≥ 40°). Kruskal-Wallis test was used to assess all the groups in terms of various items in the questionnaire, while Mann-Whitney test was used to assess every two groups. RESULTS: In overall evaluation, Group C (10°-20°) obtained the optimal expectation (p < 0.05); Group B, C and D (0°-30°) obtained better function (p < 0.05), and there was no significant difference between the 3 groups. In appearance, Group A, B and C (<20°) were better than the other groups both in function and expectation (p < 0.05), without dramatic difference among the three groups. In outdoor activities, Group A, B, C and D (<30°) were better in most of the items (p < 0.05). In indoor activities, Group C and D (10-30°) were much better (p < 0.05). CONCLUSION: AS thoracolumbar kyphotic patients with cervical ankylosis had the best satisfaction when 10° ≤ CBVA < 20°.

Effects of Hindlimb Unweighting on MBP and GDNF Expression and Morphology in Rat Dorsal Root Ganglia Neurons.

With the development of technology and space exploration, studies on long-duration space flights have shown that microgravity induces damage to multiple organs, including the dorsal root ganglia (DRG). However, very little is known about the effects of long-term microgravity on DRG neurons. This study investigated the effects of microgravity on lumbar 5 (L5) DRG neurons in rats using the hindlimb unweighting (HU) model. Male (M) and female (F) Sprague-Dawley rats were randomly divided into M- and F-control (CON) groups and M- and F-HU groups, respectively (n = 10). At the end of HU treatment for 4 weeks, morphological changes were detected. Myelin basic protein (MBP) and degenerated myelin basic protein (dgen-MBP) expressions were analyzed by immunofluorescence and western blot assays. Glial cell line-derived neurotrophic factor (GDNF) protein and mRNA expressions were also analyzed by immunohistochemistry, western blot, and RT-PCR analysis, respectively. Compared with the corresponding CON groups, the HU groups exhibited slightly loose junctions between DRG neurons, some separated ganglion cells and satellite cells, and lightly stained Nissl bodies that were of smaller size and had a scattered distribution. High levels of dgen-MBP and low MBP expressions were appeared and GDNF expressions were significantly decreased in both HU groups. Changes were more pronounced in the F-HU group than in the M-HU group. In conclusion, HU treatment induced damage of L5 DRG neurons, which was correlated with decreased total MBP protein expression, increased dgen-MBP expression, and reduced GDNF protein and mRNA expression. Importantly, these changes were more severe in F-HU rats compared with M-HU rats.

Selection of Lowest Instrumented Vertebra for Thoracolumbar Kyphosis in Ankylosing Spondylitis.

STUDY DESIGN: Retrospective study. OBJECTIVE: To determine the optimal osteotomized vertebra (OV) and lowest instrumented vertebra (LIV) in ankylosing spondylitis (AS) kyphosis. SUMMARY OF BACKGROUND DATA: Although most of AS kyphosis cases are treated by pedicle subtraction osteotomy (PSO), few studies have focused on the selection of the LIV relative to distal OV. METHODS: We reviewed all AS kyphosis cases surgically treated at our institution between 2010 and 2013. Patients were divided into groups based on the relative position of LIV and distal OV: group OV+2, the LIV was the second vertebra below OV; group OV+3, the LIV was the third vertebra below OV; group OV+4, the LIV was the fourth vertebra below OV. The preoperative and 2-year postoperative radiographic parameters and clinical data of the former two groups were compared. In addition, if the LIV was S1, patients were included in group S1, and those remaining were included in group non-S1 (the LIV was L5 or above). RESULTS: None of the patients presented fixation failure. Groups OV+2 and OV+3 had similar magnitudes of kyphosis (P > 0.05) and sagittal vertical axis corrections (P > 0.05) at the last follow-up. There was no difference in the incidence of proximal junctional kyphosis (PJK) between groups (P > 0.05). Between groups S1 and non-S1, the incidence of PJK and the magnitudes of kyphosis and sagittal vertical axis corrections were not significantly different (P > 0.05). The lumbosacral visual analogue scale and the incidence of pressure sores in group S1 were higher than in group non-S1 (P < 0.05). CONCLUSION: When PSO is performed at the level of L2 or L3, the instrumentation can be limited to the two caudal vertebra that follow. Extending the fixation to more vertebra or to the sacrum does not appear to improve the stability of the instrumentation and the fusion rate, and it is not suitable to carry out PSO at L4. LEVEL OF EVIDENCE: 4.

Changes in Sexual Activity in Male Patients Surgically Treated for Kyphosis due to Ankylosing Spondylitis.

STUDY DESIGN: A retrospective study. OBJECTIVE: The aim of this study was to assess the changes in sexual activities in male patients surgically treated for ankylosing spondylitis (AS)-induced kyphosis and the correlation between these changes and spinal sagittal realignment. SUMMARY OF BACKGROUND DATA: Sexual function may be affected by AS. However, little is known about the effect of spinal surgery on the sexual activity of patients with AS-induced kyphosis. METHODS: Data of 45 male patients who had been surgically treated for AS-induced kyphosis were retrospectively reviewed. Changes in sexual activity were evaluated by the international index of erectile function (IIEF), frequency of sexual activity, and time point at which sexual activity began postoperatively. We compared the above-mentioned parameters before and 24 months postoperatively and analyzed the correlation of the changes in the IIEF with the changes in radiological characteristics. RESULTS: Each domain of the IIEF and the total IIEF were increased postoperatively. Improved sexual function was correlated with changes in spinal sagittal characteristics, among which lumbar lordosis (LL) and the chin-brow vertical angle (CBVA) were the most significant causes (P < 0.05). Most patients (71.1%) resumed their sexual activity 5 to 12 weeks after surgery. At the 24-month follow-up, the frequency of patients' sexual activity was higher than that before surgery (P < 0.05). CONCLUSION: Surgical correction of spinal deformity may improve sexual function and increase the frequency of sexual activity in men with AS. Spinal sagittal realignment and pelvic rotation may be correlated with improvement of sexual function. LEVEL OF EVIDENCE: 4.

The radiologic, clinical results and digestive function improvement in patients with ankylosing spondylitis kyphosis after pedicle subtraction osteotomy.

BACKGROUND CONTEXT: Although there have been several reports describing the radiologic and clinical outcomes of pedicle subtraction osteotomy (PSO) in ankylosing spondylitis (AS) with spinal kyphotic deformity, little is known about the digestive function improvement in AS kyphosis after PSO. PURPOSE: The aim was to assess radiologic and clinical results and digestive function improvement in patients with AS kyphosis after PSO. STUDY DESIGN/SETTING: This was a retrospective clinical study. PATIENT SAMPLE: From January 2009 to July 2013, 53 patients in our department with AS kyphotic deformity who underwent PSO were reviewed. OUTCOME MEASURES: The globe kyphosis (GK) was measured. A health-related quality of life included Oswestry Disability Index (ODI) and Scoliosis Research Society outcomes instrument-22 (SRS-22). The acreage of the abdominal median sagittal plane (AMSPA) and the minimum distance (MD) between the xiphoid process and the spine or between the abdominal wall and the spine when the abdominal wall was folded into abdomen were measured on the three-dimensional computed tomography scans. The positional changes of abdominal viscera, such as the liver, spleen, and kidney, were also measured. Digestive function assessment included weight and the food intake (FI), and the change of the defecate frequency was recorded. METHODS: A paired sample t test was performed to determine the differences between the preoperative and postoperative MD, AMSPA, and weight, respectively. A paired sample t test was also performed to determine the differences between preoperative and postoperative Cobb angles and Oswestry Disability Index (ODI), SRS-22 for all the patients, respectively. A paired sample t test was also performed to determine the positional changes of abdominal viscera. Description date was presented as mean±standard deviation. Additionally, an independent sample t test was performed to determine the differences between the patients (Group 1) who had defecate frequency change and the remaining patients (Group 2) for preoperative GK, age, and disease duration, respectively. An independent sample t test was also performed to determine the differences between the patients (Group A) who had obviously increased FI and the remaining patients (Group B) for preoperative GK, age, and disease duration, respectively. RESULTS: All the patients had good radiologic and clinical results, postoperatively. The postoperative positions of the abdominal viscera were changed significantly. The weight, the mass of FI, and the defecate frequency were also changed significantly, postoperatively. The preoperative GK, age, and disease duration were not significantly statistical different between the patients who had defecate frequency change and the remaining patients, respectively. There were also not significantly statistical differences between the patients who had obviously increased FI and the remaining patients in preoperative age and disease duration. There was a significantly statistical difference between the patients who had obviously increased FI and the remaining patients for preoperative GK. CONCLUSIONS: The single-level or two-level PSO is an effective and safe technique to correct AS kyphosis. And the conditions of extrusion of viscera by trunk flexion decreased volume of the abdominal cavity, and abnormal visceral positions were improved by the osteotomy, followed with digestive function improvement.

Effect of Preoperative Tracheal Stretch Exercise on Anterior Cervical Spine Surgery: A Retrospective Study.

STUDY DESIGN: We designed a retrospective study on preoperative tracheal stretch exercise (TSE) before anterior cervical spine surgery. The changes in vital signs before and during the surgery and the postoperative clinical outcome were recorded and compared with none treated patients. OBJECTIVE: The aim of this study was to evaluate whether the preoperative TSE is beneficial to the anterior cervical spine surgery and clinical outcome. SUMMARY OF BACKGROUND DATA: Anterior approach to the cervical spine surgery requires prolonged retraction of the trachea and esophagus. Although the surgery can be managed to complete, related potential complications may occur. METHODS: This is a retrospective study on 128 patients scheduled for anterior cervical spine surgery. Patients in the stretched group received preoperative TSE for 3 consecutive days before surgery, whereas the control group did not. During the preoperative exercise and the surgery, the changes in the vital signs were recorded and compared with the control group. The visual analogue scale, neck disability index (NDI), and the Clinical Symptom Score of the Japanese Orthopaedic Association (JOA) were also compared at different follow-up intervals, including 1, 3, and 6 months postoperation. RESULTS: The changes in blood pressure, heart rate, and respiratory and swallowing rates during the first exercise are significantly greater than those during the last exercise (P<0.05). During the surgery, changes in the vital signs in the exercise patients are also significantly smaller than those in control patients (P<0.05), excluding the blood oxygen saturation. The significant differences were also observed with the postoperative NDI and JOA scores between the exercise and control group at 6 months (P<0.05). CONCLUSIONS: Proper and systematic preoperative TSE has great significance for the success of anterior cervical spine surgery.

Different angiogenic abilities of self-setting calcium phosphate cement scaffolds consisting of different proportions of fibrin glue.

To investigate the different angiogenic abilities of the self-setting calcium phosphate cement (CPC) consisting of different proportions of fibrin glue (FG), the CPC powder and the FG solution were mixed at the powder/liquid (P/L) ratios of 1 : 0.5, 1 : 1, and 1 : 2 (g/mL), respectively, and pure CPC was used as a control. After being implanted into the lumbar dorsal fascia of the rabbit, the angiogenic process was evaluated by histological examination and CD31 immunohistochemistry to detect the new blood vessels. The result of the new blood vessel showed that the P/L ratio of 1 : 1 group indicated the largest quantity of new blood vessel at 4 weeks, 8 weeks, and 12 weeks after implantation, respectively. The histological evaluation also showed the best vascular morphology in the 1 : 1 group at 4 weeks, 8 weeks, and 12 weeks after the operation, respectively. Our study indicated that the CPC-FG composite scaffold at the P/L ratio of 1 : 1 (g/mL) stimulated angiopoiesis better than any other P/L ratios and has significant potential as the bioactive material for the treatment of bone defects.

Mitochondrial regulation of NADPH oxidase in hindlimb unweighting rat cerebral arteries.

Exposure to microgravity results in post-flight cardiovascular deconditioning and orthostatic intolerance in astronauts. Vascular oxidative stress injury and mitochondrial dysfunction have been indicated in this process. To elucidate the mechanism for this condition, we investigated whether mitochondria regulated NADPH oxidase in hindlimb unweighting (HU) rat cerebral and mesenteric arteries. Four-week HU was used to simulate microgravity in rats. Vascular superoxide generation, protein and mRNA levels of Nox2/Nox4, and the activity of NADPH oxidase were examined in the present study. Compared with control rats, the levels of superoxide increased in cerebral (P<0.001) but not in mesenteric vascular smooth muscle cells. The protein and mRNA levels of Nox2 and Nox4 were upregulated significantly (P<0.001 and P<0.001 for Nox2, respectively; P<0.001 and P<0.001 for Nox4, respectively) in HU rat cerebral arteries but not in mesenteric arteries. NADPH oxidases were activated significantly by HU (P<0.001) in cerebral arteries but not in mesenteric arteries. Chronic treatment with mitochondria-targeted antioxidant mitoTEMPO attenuated superoxide levels (P<0.001), decreased the protein and mRNA expression levels of Nox2/Nox4 (P<0.01 and P<0.05 for Nox2, respectively; P<0.001 and P<0.001 for Nox4, respectively) and the activity of NADPH oxidase (P<0.001) in HU rat cerebral arteries, but exerted no effects on HU rat mesenteric arteries. Therefore, mitochondria regulated the expression and activity of NADPH oxidases during simulated microgravity. Both mitochondria and NADPH oxidase participated in vascular redox status regulation.

Two-level spinal osteotomy for severe thoracolumbar kyphosis in ankylosing spondylitis. Experience with 48 patients.

STUDY DESIGN: A retrospective study. OBJECTIVE: To report surgical results for severe thoracolumbar kyphosis secondary to ankylosing spondylitis (AS) corrected with 2-level spinal osteotomy. SUMMARY OF BACKGROUND DATA: Transpedicular osteotomy in the lumbar spine is the major approach to correct kyphosis in AS. Most surgical procedures were performed at 1 level and only few literature report 2-level osteotomy in 1 patient. METHODS: From January 2003 to June 2011, we reviewed 48 patients experiencing AS with severe thoracolumbar kyphosis who underwent stage 2-level spinal osteotomy in our hospital. The osteotomies were performed at T12 and L2 or L1 and L3, according to the apex of kyphosis. Preoperative and postoperative height, chin-brow vertical angle, sagittal balance, and the sagittal Cobb angle of the vertebral osteotomy segment were documented. Intraoperative, postoperative, and general complications were recorded. RESULTS: The chin-brow vertical angle improved from 65.0° ± 28.0° to 5.0°± 10.0° (P = 0.000) and the sagittal imbalance distance improved from 26.9 ± 10.4 cm to 10.6 ± 5.6 cm (P = 0.000). The mean amount of correction was 24.9° at the superior site of the osteotomy and 38.1° at the inferior site of the osteotomy. Postoperatively, all patients could walk with horizontal vision and lie on their backs. No major acute complications such as death or complete paralysis occurred. Five patients experienced complications such as infections (n = 1) and cerebrospinal fluid leaks (n = 4). Both Oswestry Disability Index and Scoliosis Research Society scores improved largely. Fusion at the osteotomy site was achieved in each patient, and no implant failures were noted. CONCLUSION: Single-stage 2-level osteotomy can effectively and safely correct kyphotic deformities of the thoracolumbar spine caused by AS. LEVEL OF EVIDENCE: 3.

Simulated microgravity-induced mitochondrial dysfunction in rat cerebral arteries.

Exposure to microgravity results in cardiovascular deconditioning, and cerebrovascular oxidative stress injury has been suggested to occur. To elucidate the mechanism for this condition, we investigated whether simulated microgravity induces mitochondrial dysfunction in rat arteries. Four-week hindlimb unweighting (HU) was used to simulate microgravity in rats. Mitochondrial reactive oxygen species (ROS), mitochondrial membrane potential (Δψm), mitochondrial permeability transition pore (mPTP) opening, mitochondrial respiratory control ratio (RCR), MnSOD/GPx activity and expression, and mitochondrial malondialdehyde (MDA) were examined in rat cerebral and mesenteric VSMCs. Compared with the control rats, mitochondrial ROS levels, mPTP opening, and MDA content increased significantly (P<0.001, P<0.01, and P<0.01, respectively), Δψm, RCR, MnSOD/GPx activity (P<0.001 for Δψm and RCR; P<0.05 for MnSOD; and P<0.001 for GPx activity) and protein abundance of mitochondrial MnSOD/GPx-1 decreased (P<0.001 for MnSOD and GPx-1) in HU rat cerebral but not mesenteric arteries. Chronic treatment with NADPH oxidase inhibitor apocynin and mitochondria-targeted antioxidant mitoTempol promoted recovery of mitochondrial function in HU rat cerebral arteries, but exerted no effects on HU rat mesenteric arteries. Therefore, simulated microgravity resulted in cerebrovascular mitochondrial dysfunction, and crosstalk between NADPH oxidase and mitochondria participated in the process.

ARHI overexpression induces epithelial ovarian cancer cell apoptosis and excessive autophagy.

OBJECTIVE: ARHI is a maternally imprinted tumor suppressor gene that is responsible for initiating programmed cell death and inhibiting cancer cell growth. However, the influence of ARHI on epithelial ovarian cancer cell death and the underlying mechanisms behind how ARHI regulates cancer cells still require further studies. METHODS: Epithelial ovarian cancer cells TOV112D and ES-2 were used in this in vitro study. Cell proliferation, apoptosis, and autophagy activities were compared in TOV112D and ES-2 cells transfected with ARHI vectors or control vectors. Bcl-2 siRNA was transfected into TOV112D cells to investigate the roles of Bcl-2 played in regulating apoptosis and autophagy. RESULTS: ARHI expression was reduced in TOV112D and ES-2 cells compared with normal epithelial ovarian cells (NOE095 and HOSEpiC). Overexpressed ARHI inhibited cancer cell proliferation, whereas induced forced cell apoptosis and excessive formation of autophagosomes inhibited promoted cell death. Furthermore, we found that Bcl-2 expression moderately declined in response to ARHI overexpressing in ES-2 and TOV112D cells; meanwhile, more apoptotic cells and higher LC3 level presented after silence of Bcl-2 in TOV112D cells. Reduced Bcl-2-Beclin 1 complex were observed in ARHI overexpressing cells. Moreover, modulation of ARHI to Bcl-2 expression could be ascribed partially to the activation of PI3k/AKT pathway. The addition of LY294002 enabled to suppress Bcl-2 expression and cell proliferation. CONCLUSIONS: The silence of ARHI expression in vitro seems to accelerate the malignant transformation of healthy ovarian cells by restraining apoptosis and autophagy. The overexpressed ARHI in TOV112D cancer cells suppresses the activation of PI3K/AKT and reduces the expression of Bcl-2, leading to enhanced cell apoptosis and autophagic cancer cell death.

Hilus pulmonis as the center of gravity for AS thoracolumbar kyphosis.

INTRODUCTION: The sagittal vertical axis (SVA) is a meaningful measurement and widely used for evaluating sagittal balance, and is considered a design standard for surgery, including most ankylosing spondylitis (AS) kyphotic deformity planning. However, recent research indicates that the C7 plumb line is actually not the center of gravity (CG) line. Therefore, whether there is a better radiological marker as the CG of the trunk for AS thoracolumbar kyphosis remains unknown. This research is to investigate a radiological marker for the CG of the trunk in lateral radiographs for AS thoracolumbar kyphosis. MATERIALS AND METHODS: The center of gravity of an irregular object can be obtained by hanging or supporting it in different points and directions, and the CG will be on the point of intersection. According to this principle of mechanics, we could use the pre- and post-operative hip axis vertical lines to locate the CG of the trunk. We evaluated 38 AS-fixed thoracolumbar kyphotic patients with pedicle subtraction osteotomies. Full-length, free-standing lateral radiographs, including the spine and pelvis, were available for all patients. Pre- and post-operative radiological parameters were measured, including SVA, horizontal distance between hip axis and C7 (HDHC), horizontal distance between hip axis and T5 (HDHT5), horizontal distance between hip axis and T9 (HDHT9), and horizontal distance between hip axis and hilus pulmonis (HDHH). Pre- and post-operative radiological parameter changes were compared by paired samples t tests. The intraclass correlation coefficient (ICC) was used to determine the intra- and interobserver reliabilities of HDHH. RESULTS: Pre-operative SVA, HDHC, HDHT5, HDHT9, and HDHH values were, respectively, 21.1, 12.7, 3.5, -3.8, and 2.7 cm, and their post-operative values were, respectively, 9.1, 4.2, -2.1, -5.6, and 0.9 cm. Changes in SVA, HDHC, HDHT5, and HDHT9 were significant (p < 0.05), while the change in HDHH was not (p > 0.05). The ICC for overall interobserver reliability was 0.958 (p < 0.001), and it was 0.963 (p < 0.001) for overall intraobserver reliability. CONCLUSION: The hilus pulmonis fell approximately on the hip axis both pre- and post-operatively. It was a better marker as the center of gravity of the trunk for deformity planning for AS thoracolumbar kyphosis.