Treatment of degenerative lumbar scoliosis using transforaminal lumbar interbody fusion based on the concept of intervertebral correction.

PURPOSE: The study aimed to examine the outcomes of posterior approach transforaminal lumbar interbody fusion (TLIF) in the treatment of degenerative lumbar scoliosis (DLS) based on the concept of intervertebral correction. METHODS: A retrospective analysis was performed on 76 surgical patients (36 males and 40 females) who underwent posterior TLIF and internal fixation based on the concept of intervertebral correction in Shenzhen Traditional Chinese Medicine Hospital from February 2014 to March 2021.The operation duration, intraoperative blood loss, incision length, and complications were recorded. Clinical efficacy was evaluated preoperatively and postoperative time points through the visual analog scale (VAS) and the Oswestry disability index (ODI). The changes in the coronal scoliosis curve (Cobb angle), coronal balance distance (CBD), the sagittal vertical axis (SVA), lumbar lordosis (LL), and pelvic tilt angle (PT) were assessed perioperatively at the last follow-up. RESULTS: All patients successfully underwent the operation. The average operation duration was 243.81 ± 35.35 (220 - 350) min; the average intraoperative blood loss was 836.27 ± 50.28 (700 - 2500) mL; the average incision length was 8.30 ± 2.33 (8 - 15) cm. The total complication rate was 18.42% (14/76). The VAS score of low back pain, lower extremity pain, and ODI score of patients at the last follow-up was significantly improved compared with those before the operation (P < 0.05). At the last follow-up, the Cobb Angle, CBD, SVA, and PT of patients were significantly lower than those before the operation (P < 0.05), and LL was higher than those before the operation (P < 0.05). CONCLUSION: TLIF based on the concept of intervertebral correction for the treatment of DLS may provide favourable clinical outcomes.

Preliminary evidence for an influence of exposure to polycyclic aromatic hydrocarbons on the composition of the gut microbiota and neurodevelopment in three-year-old healthy children.

BACKGROUND: During the second and third year after birth the gut microbiota (GM) is subjected to important development. The polycyclic aromatic hydrocarbon (PAH) exposure could influence the GM in animal and early postnatal exposure is associated with neurodevelopment disorder in children. This study was designed to explore the possible influence of the polycyclic aromatic hydrocarbons (PAHs) on the composition of the gut microbiota (GM) and neurodevelopment in a sample of 38 healthy children at the age of 3 years. METHODS: A brief development (Gesell Development Inventory, GDI) and behavior test (Child Behavior Checklist, CBCL) were completed on 3-yr-olds and stool samples were collected for 16S rRNA V4-V5 sequencing. The PAH-DNA adduct in the umbilical cord blood and the urinary hydroxyl PAHs (OH-PAHs) at the age of 12 months were measured as pre- and postnatal PAH exposure, respectively. RESULTS: The most abundant two phyla were Bacteroidetes (68.6%) and Firmicutes (24.2%). The phyla Firmicutes, Actinobacteria, Proteobacteria, Tenericutes, and Lentisphaerae were positively correlated with most domain behaviors of the GDI, whereas the Bacteroidetes, Cyanobacteria, and Fusobacteria were negatively correlated. Correspondingly, the phyla Bacteroidetes, Actinobacteria, and Fusobacteria showed positive correlations with most CBCL core and broadband syndromes, whereas the Firmicutes, Verrucomicrobia, Synergistetes, Proteobacteria and Tenericules were negatively correlated. The OH-PAH levels were not significantly associated with the Firmicutes phylum whereas the Bacteroidetes, Bacteroidia, and Bacteroidales all showed significant negative association with the OH-PAH levels. CONCLUSION: The current findings suggest that composition of the GM is associated with neurodevelopment of the child. PAHs seem to change the relative abundance of some taxa (some deleted and some recruited) to counteract the negative effects of the PAHs.

[Regulation of single herb pilose antler on the expression of Smad2 and Smad3 in the cartilage of OA rats: an experimental research].

OBJECTIVE: To observe the effect of single herb pilose antler (PA) on the expression of Smad2 and Smad3 in the cartilage of osteoarthritis (OA) rats. METHODS: One hundred 3-month old female healthy SD rats, (200 +/- 20) g, were recruited and routinely fed for 1 week. They were randomly divided into 5 groups, i.e., the low dose PA group, the high dose PA group, the normal saline control group, the model group, and the normal control group, 20 in each group. The model was prepared using classic Hulth method except the normal control group. After 6-week modeling, the model was confirmed successful by pathologic observation. PA at 0.021 g/100 g and 0.084 g/1 00 g was given by gastrogavage to rats in the low dose PA group and the high dose PA group respectively. Normal saline was administered to those in the normal saline control group. No treatment was given to rats in the normal control group and the model group. Bilateral knee cartilages were harvested at week 2,4, and 6. mRNA and protein expressions of Smad2 and Smad3 were detected by immunohistochemical assay, fluorescent quantitative PCR, and Western blot. RESULTS: OA model was successfully prepared by pathological observation. Results of immunohistochemical assay showed that Smad2 and Smad3 expressed extensively in the cartilage, and located inside the chondrocyte membrane. Compared with the model group, mRNA expression of Smad2 and Smad3 obviously increased in the low dose PA group and the high dose PA group at week 2, 4, and 6, showing statistical difference (P < 0.05). Compared with the same group at week 4 after gastrogavage, mRNA expression of Smad2 and Smad3 obviously decreased in the low dose PA group and the high dose PA group at week 6, showing statistical difference (P < 0.05). Compared with the model group, protein expression of Smad2 and Smad3 obviously increased in the chondrocytes of the low dose PA group and the high dose PA group at week 2 and 4, showing statistical difference (P < 0.01). Compared with the same group at week 2 after gastrogavage, protein expression of Smad2 and Smad3 obviously increased in the low dose PA group and the high dose PA group at week 4, showing statistical difference (P < 0.01). Compared with the same group at week 4 after gastrogavage, protein expression of Smad2 and Smad3 obviously decreased in the low dose PA group and the high dose PA group at week 6, showing statistical difference (P < 0.01). CONCLUSIONS: (1) The pilose antler could repair cartilages by regulating mRNA and protein expressions of Smad2 and Smad3. (2) Up-regulating mRNA and protein expressions of Smad2 and Smad3 might be one of important mechanisms for the pathogenesis of OA.

Sagittal balance parameters measurement on cervical spine MR images based on superpixel segmentation.

Introduction: Magnetic Resonance Imaging (MRI) is essential in diagnosing cervical spondylosis, providing detailed visualization of osseous and soft tissue structures in the cervical spine. However, manual measurements hinder the assessment of cervical spine sagittal balance, leading to time-consuming and error-prone processes. This study presents the Pyramid DBSCAN Simple Linear Iterative Cluster (PDB-SLIC), an automated segmentation algorithm for vertebral bodies in T2-weighted MR images, aiming to streamline sagittal balance assessment for spinal surgeons. Method: PDB-SLIC combines the SLIC superpixel segmentation algorithm with DBSCAN clustering and underwent rigorous testing using an extensive dataset of T2-weighted mid-sagittal MR images from 4,258 patients across ten hospitals in China. The efficacy of PDB-SLIC was compared against other algorithms and networks in terms of superpixel segmentation quality and vertebral body segmentation accuracy. Validation included a comparative analysis of manual and automated measurements of cervical sagittal parameters and scrutiny of PDB-SLIC's measurement stability across diverse hospital settings and MR scanning machines. Result: PDB-SLIC outperforms other algorithms in vertebral body segmentation quality, with high accuracy, recall, and Jaccard index. Minimal error deviation was observed compared to manual measurements, with correlation coefficients exceeding 95%. PDB-SLIC demonstrated commendable performance in processing cervical spine T2-weighted MR images from various hospital settings, MRI machines, and patient demographics. Discussion: The PDB-SLIC algorithm emerges as an accurate, objective, and efficient tool for evaluating cervical spine sagittal balance, providing valuable assistance to spinal surgeons in preoperative assessment, surgical strategy formulation, and prognostic inference. Additionally, it facilitates comprehensive measurement of sagittal balance parameters across diverse patient cohorts, contributing to the establishment of normative standards for cervical spine MR imaging.

Helical fused 1,2:8,9-dibenzozethrene oligomers with up to 201° end-to-end twist: "one-pot" synthesis and chiral resolution.

Twisted polyarenes with persistent chirality are desirable but their synthesis has remained a challenge. In this study, we present a "one-pot" synthesis of 1,2:8,9-dibenzozethrene (DBZ) and its vertically fused dimers and trimers using nickel-catalyzed cyclo-oligomerization reactions. X-ray crystallographic analysis confirmed highly twisted helical structures that consist of equal parts left- and right-handed enantiomers. Notably, the end-to-end twist between the terminal anthracene units measured 66°, 130°, and 201° for the DBZ monomer, dimer, and trimer, respectively, setting a new record among twisted polyarenes. Furthermore, the chiral resolution by HPLC yielded two enantiomers for the fused DBZ dimer and trimer, both of which maintained stable configurations and showed absorption dissymmetry factors of around 0.008-0.009. Additionally, their optical and electrochemical properties were investigated, which exhibited a chain-length dependence.

[Robot-assisted PVP for the treatment of osteoporotic fractures of the upper thoracic vertebra].

OBJECTIVE: To investigate the clinical effect of "Tianji" orthopedic robot-assisted percutaneous vertebro plasty(PVP) surgery in the treatment of upper thoracic osteoporotic fracture. METHODS: A retrospective analysis was performed on 32 patients with upper thoracic osteoporotic fracture who underwent PVP surgery in Shenzhen Hospital of Traditional Chinese Medicine from August 2016 to June 2022. There were 8 males and 24 females, ranging in age from 58 to 90 years old, with a mean of (67.75±12.27) years old. Fifteen patients were treated with robot-assisted PVP surgery (robot group), including 3 males and 12 females, with an average age of (68.5±10.3) years. Fracture location:1 case of T2 fracture, 1 case of T3 fracture, 3 cases of T4 fracture, 3 cases of T5 fracture, and 7 cases of T6 fracture. The follow-up period ranged from 1.0 to 3.0 months, with a mean of (1.6±0.7) months. Seventeen patients underwent routine PVP surgery (conventional group), including 5 males and 12 females, with an average age of (66.8±11.6) years old. Fracture location:1 case of T1 fracture, 5 cases of T4 fracture, 2 cases of T5 fracture and 9 cases of T6 fracture. The follow-up period ranged from 0.5 to 4.0 months, with a mean of (1.5±0.6) months. Preoperative and postoperative visual analogue scale(VAS) and Oswestry disability index(ODI) scores were compared between the two groups, and the number of punctures, perspective times, operation time, intraoperative blood loss, bone cement distribution, bone cement leakage, and intraoperative radiation dose were compared between the two groups. RESULTS: Number of punctures times, perspective times, operation time, intraoperative blood loss, bone cement distribution, bone cement leakage and intraoperative radiation dose in the robot group were all significantly better than those in the conventional group(P<0.05). VAS of 2.03±0.05 and ODI of (22.16±4.03) % in the robot group were significantly better than those of the robot group before surgery, which were (8.67±0.25) score and (79.40±7.72)%(t=100.869, P<0.001;t=25.456, P<0.001). VAS of 2.17±0.13 and ODI of (23.88±6.15)% in the conventional group were significantly better than those before surgery, which were (8.73±0.18) score and (80.01±7.59)%(t=121.816, P<0.001;t=23.691, P<0.001). There was no significant difference in VAS and ODI between the two groups after operation (t=-3.917, P=0.476;t=-0.922, P=0.364). CONCLUSION: Robot-assisted PVP in the treatment of upper thoracic osteoporotic fractures can further improve surgical safety, reduce bone cement leakage, and achieve satisfactory clinical efficacy.

Synovial Fluid Mesenchymal Stem Cells for Knee Arthritis and Cartilage Defects: A Review of the Literature.

Mesenchymal stem cells (MSCs) are adult stem cells that have the ability to self-renew and differentiate into several cell lineages including adipocytes, chondrocytes, tenocytes, bones, and myoblasts. These properties make the cell a promising candidate for regenerative medicine applications, especially when dealing with sports injuries in the knee. MSCs can be isolated from almost every type of adult tissue. However, most of the current research focuses on MSCs derived from bone marrow, adipose, and placenta derived products. Synovial fluid-derived MSCs (SF-MSCs) are relatively overlooked but have demonstrated promising therapeutic properties including possessing higher chondrogenic proliferation capabilities than other types of MSCs. Interestingly, SF-MSC population has shown to increase exponentially in patients with joint injury or disease, pointing to a potential use as a biomarker or as a treatment of some orthopaedic disorders. In this review, we go over the current literature on synovial fluid-derived MSCs including the characterization, the animal studies, and discuss future perspectives.

Effect of hydroxyl on antioxidant properties of 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one to scavenge free radicals.

It is well known that 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one (DDMP) is usually formed in the Maillard reaction and it contributes to the antioxidant properties of Maillard reaction intermediates. A series of hydroxyl group protected DDMP derivatives were synthesized to further understand the source of antioxidant activity. Antioxidant abilities of the DDMP derivatives were evaluated by scavenging the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) cationic radical (ABTS˙+), 2,2'-diphenyl-1-picrylhydrazyl radical (DPPH), and galvinoxyl radical, respectively. It was found that the introduction of protecting groups to the free hydroxyl groups of DDMP decreases their reducing abilities. In particular, the hydroxyl group at the olefin position exhibited a remarkable impact on the antioxidant activity of DDMP, indicating that the unstable enol structure in the DDMP moiety is the key factor for its antioxidant activity.

Influence of postnatal polycyclic aromatic hydrocarbon exposure on the neurodevelopment of toddlers at the age of 12 months.

OBJECTIVES: To investigate the possible influence of polycyclic aromatic hydrocarbons (PAHs) exposure on neurodevelopment of toddlers at the age of 12 months. METHODS: Totally 306 subjects were recruited from the Qingdao Birth Cohort established in 2014. PAH-DNA adducts in toddlers' umbilical cord blood samples, hydroxyl-PAH metabolites in their urine samples and the developmental quotients (DQs) were measured. Sex, gestational age, birth weight, and maternal educational background were adjusted to analyze the influence of the PAH exposure on the neurodevelopment of the toddlers using multivariate linear regression model. RESULTS: Pearson correlation test showed that the logarithmic values of hydroxyl-PAH were negatively correlated with the DQs. Multivariate linear regression analysis indicated that logarithmic concentration of 1(9)- hydroxyphenanthrene was still associated with the DQs of the fine motor behaviors with ß and 95% confidential interval (CI) of -1.137 (-2.053, -0.222), together with PAH-DNA adducts [ß (95% CI): -0.577 (-0.930, -0.225)]. PAH-DNA adducts presented an independently negative influence on the DQs of the gross motor and personal social behaviors with ß (95%CI) of -0.470 (-0.814, -0.126) and -0.526 (-0.859, -0.193), respectively. CONCLUSIONS: The exposure to PAHs in toddlers at 12 months could influence their neurodevelopment. Additionally, prenatal exposure to PAHs should also be considered.

Curcumol Alleviates the Inflammation of Nucleus Pulposus Cells via the PI3K/Akt/NF-κB Signaling Pathway and Delays Intervertebral Disk Degeneration.

BACKGROUND: Intervertebral disk degeneration (IVDD) is closely associated with inflammatory environments. Curcumol has been shown to alleviate inflammation in various disease models, but its effects on IVDD remain unclear. In this study, we sought to determine the mechanism of curcumol in tumor necrosis factor (TNF)-α-induced nucleus pulposus cells and a mouse IVDD model. METHODS: Nucleus pulposus cells were pretreated with curcumol and then exposed to TNF-α. Cell viability was analyzed using CCK-8, and the messenger ribonucleic acid and protein levels of inflammatory cytokines and PI3K/Akt/NF-κB-related signaling molecules were detected using real-time polymerase chain reaction, enzyme-linked immunosorbent assay, and western blotting. The mouse IVDD model was established by puncturing the C6/7 level of the caudal spine, and then it was treated with curcumol after surgery. Alcian blue/orange G staining was performed to evaluate the severity of intervertebral disk damage, and immunohistochemistry was performed to detect the expression of TNF-α. Toxicologic effects of curcumol were measured by performing hematoxylin-eosin staining and enzyme-linked immunosorbent assay. RESULTS: Curcumol reduced IL-1ß, IL-6, and TNF-α production in NPCs, and the phosphorylation of proteins in the PI3K/Akt/NF-κB signaling pathway was also decreased. The PI3K/Akt/NF-κB-related signaling molecules decreased when TNF-α-induced NPCs were treated with a PI3K inhibitor; however, curcumol did not reverse these effects. In vivo, curcumol ameliorated the progression of IVDD at the early stage and did not exert toxicologic effects. CONCLUSIONS: These results suggest a potential therapeutic use of curcumol to alleviate inflammation via the PI3K/Akt/NF-κB signaling pathway and delay the progression of IVDD.

Aberrant spinal mechanical loading stress triggers intervertebral disc degeneration by inducing pyroptosis and nerve ingrowth.

Aberrant mechanical factor is one of the etiologies of the intervertebral disc (IVD) degeneration (IVDD). However, the exact molecular mechanism of spinal mechanical loading stress-induced IVDD has yet to be elucidated due to a lack of an ideal and stable IVDD animal model. The present study aimed to establish a stable IVDD mouse model and evaluated the effect of aberrant spinal mechanical loading on the pathogenesis of IVDD. Eight-week-old male mice were treated with lumbar spine instability (LSI) surgery to induce IVDD. The progression of IVDD was evaluated by µCT and Safranin O/Fast green staining analysis. The metabolism of extracellular matrix, ingrowth of sensory nerves, pyroptosis in IVDs tissues were determined by immunohistological or real-time PCR analysis. The apoptosis of IVD cells was tested by TUNEL assay. IVDD modeling was successfully produced by LSI surgery, with substantial reductions in IVD height, BS/TV, Tb.N. and lower IVD score. LSI administration led to the histologic change of disc degeneration, disruption of the matrix metabolism, promotion of apoptosis of IVD cells and invasion of sensory nerves into annulus fibrosus, as well as induction of pyroptosis. Moreover, LSI surgery activated Wnt signaling in IVD tissues. Mechanical instability caused by LSI surgery accelerates the disc matrix degradation, nerve invasion, pyroptosis, and eventually lead to IVDD, which provided an alternative mouse IVDD model.

GISSD: Group I Intron Sequence and Structure Database.

Group I Intron Sequence and Structure Database (GISSD) is a specialized and comprehensive database for group I introns, focusing on the integration of useful group I intron information from available databases and providing de novo data that is essential for understanding these introns at a systematic level. This database presents 1789 complete intron records, including the nucleotide sequence of each annotated intron plus 15 nt of the upstream and downstream exons, and the pseudoknots-containing secondary structures predicted by integrating comparative sequence analyses and minimal free energy algorithms. These introns represent all 14 subgroups, with their structure-based alignments being separately provided. Both structure predictions and alignments were done manually and iteratively adjusted, which yielded a reliable consensus structure for each subgroup. These consensus structures allowed us to judge the confidence of 20 085 group I introns previously found by the INFERNAL program and to classify them into subgroups automatically. The database provides intron-associated taxonomy information from GenBank, allowing one to view the detailed distribution of all group I introns. CDSs residing in introns and 3D structure information are also integrated if available. About 17 000 group I introns have been validated in this database; approximately 95% of them belong to the IC3 subgroup and reside in the chloroplast tRNA(Leu) gene. The GISSD database can be accessed at http://www.rna.whu.edu.cn/gissd/

Suppression of Oxygen Vacancy Defects in sALD-ZnO Films Annealed in Different Conditions.

Zinc oxide (ZnO) has drawn much attention due to its excellent optical and electrical properties. In this study, ZnO film was prepared by a high-deposition-rate spatial atomic layer deposition (ALD) and subjected to a post-annealing process to suppress the intrinsic defects and improve the crystallinity and film properties. The results show that the film thickness increases with annealing temperature owing to the increment of oxide layer caused by the suppression of oxygen vacancy defects as indicated by the X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) spectra. The film transmittance is seldom influenced by annealing. The refractive index increases with annealing temperature at 300-700 °C, possibly due to higher density and crystallinity of the film. The band gap decreases after annealing, which should be ascribed to the decrease in carrier concentration according to Burstein-Moss model. The carrier concentration decreases with increasing annealing temperature at 300-700 °C since the oxygen vacancy defects are suppressed, then it increases at 800 °C possibly due to the out-diffusion of oxygen atoms from the film. Meanwhile, the carrier mobility increases with temperature due to higher crystallinity and larger crystallite size. The film resistivity increases at 300-700 °C then decreases at 800 °C, which should be ascribed primarily to the variation of carrier concentration.

Comparison of the Safety and Effectiveness of Percutaneous Endoscopic Lumbar Discectomy for Treating Lumbar Disc Herniation Under Epidural Anesthesia and General Anesthesia.

OBJECTIVE: To assess the safety and effectiveness of percutaneous endoscopic lumbar discectomy (PELD) under epidural anesthesia (EA) and general anesthesia (GA) for treating lumbar disc herniation (LDH). METHODS: A retrospective study involving 86 patients with LDH managed by PELD under EA and GA was conducted from July 2018 to March 2019. These patients were divided into 2 groups according to the type of anesthesia. Patient's demographics data as well as the operation time, complications, fluoroscopy shots, visual analog scale (VAS), Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA), and MacNab scores of the 2 groups were recorded. All of the patients were followed-up at 6 months after operation. RESULTS: There were no significant differences were detected in the preoperative demographics between the groups (p > 0.05). Two cases (4.8%) under GA developed transient motor weakness, 3 cases (7.4%) presented numbness of lower limb, and 1 case (2.4%) had cauda equina syndrome after operation. In EA group, 1 case (2.2%) had motor weakness and 3 cases (6.7%) had lower limb numbness, which resolved completely at the last follow-up. There was significant difference between preoperative VAS, JOA, and ODI scores and postoperative scores (p < 0.01). Moreover, there were no differences in the operation time, fluoroscopy shots, and MacNab scores between the 2 groups (p > 0.05). CONCLUSION: EA and GA in PELD are effective and safe, and no significant difference in complications was observed. Based on our experience, we recommended junior surgeons to perform PELD under EA for getting feedback from the patient to avoid nerve injury and reduce the radiation dose. The concentration of ropivacaine in EA should be considered carefully.

Zinc Oxide Films with High Transparency and Crystallinity Prepared by a Low Temperature Spatial Atomic Layer Deposition Process.

Zinc oxide (ZnO) attracts much attention owing to its remarkable electrical and optical properties for applications in optoelectronics. In this study, ZnO thin films were prepared by spatial atomic layer deposition with diethylzinc and water as precursors. The substrate temperature was varied from 55 to 135 °C to investigate the effects on the optical, electrical, and structural properties of the films. All ZnO samples exhibit an average transmittance in visible and near-infrared light range exceeding 80% and a resistivity in the range of (3.2-9.0) × 10-3 Ω·cm when deposited on a borosilicate glass with a refractive index of ≈1.52. The transmittance, band gap, refractive index, and extinction coefficient are rarely affected, while the resistivity only slightly decreases with increasing temperature. This technique provides a wide process window for depositing ZnO thin films. The results revealed that the films deposited at a substrate of 55 °C were highly crystalline with a preferential (1 0 0) orientation. In addition, the grains grow larger as the substrate temperature increases. The electrical properties and reliability of ZnO/PET samples are also studied in this paper.

Investigation of growth kinetics and partial denitrification performance in strain Acinetobacter johnsonii under different environmental conditions.

A denitrifying strain ZY04 with a high nitrite-accumulating rate was isolated and purified from activated sludge in a laboratory-scale A2/O reactor. The strain was characterized and identified as Acinetobacter johnsonii by 16S rDNA phylogenetic analysis. The sequences of the key functional genes (napA, nirB, nirD) involved in partial denitrification were amplified via polymerase chain reaction, which provided a basis for exploring gene expression. The effects of different environmental factors (C/N ratio, pH and temperature) on the partial denitrification performance and transcriptional levels of the functional genes during the logarithmic growth phase were investigated by batch experiments. The results showed that the partial denitrification performance was optimal when the C/N ratio was 5, the pH value was 6-8 and the temperature was 25°C. The gene expression during the logarithmic growth phase indicated the good performance of partial denitrification under different environmental conditions. All three functional genes exhibited the highest expression levels at 25°C. The results of inhibitory kinetics analysis revealed that three biokinetic models (Aiba, Edwards and Andrews) simulated the growth pattern of strain ZY04 inhibited by a single substrate (nitrate or sodium acetate) well. In the double-substrate inhibitory model, five models of nine combinations successfully fitted the growth characteristics of the strain affected by the double substrate of nitrate and sodium acetate. The relevant semi-saturation parameters and substrate inhibition parameters were obtained, and the correlation coefficient (R 2) reached 98%.

[Finite element analysis of maxillary anterior teeth retraction of posterior teeth with different alveolar bone absorption heights under orthodontic force].

OBJECTIVE: This study applied the direct orthodontic force system to explore the applicability of the finite element method in the simulation of alveolar bone absorption and analyze periodontal stress distribution and the overall displacement trend. METHODS: The horizontal balanced alveolar bones of model 2, 3 and 4 were reduced by 2, 4, and 6 mm by deleting elements in reference to the established height of the normal alveolar bone model 1. Then, stress distribution on the posterior set of teeth and initial total tooth displacement under the simulated load of 1.47 N of orthodontic force were investigated. RESULTS: The total displacement of posterior teeth increased and parodontium Von Mises stress gradually increased as the alveolar bone height decreased. The total displacement trend and parodontium stress drastically increased when alveolar bone absorp-tion reached the height of 4 mm. CONCLUSIONS: When treating patients with alveolar bone loss, stress should be avoided or drasti-cally reduced to prevent irreversible damage to periodontal tissue and to improve the quality of medical treatment.

Simultaneous nitrification and denitrification by a novel isolated Pseudomonas sp. JQ-H3 using polycaprolactone as carbon source.

The novel isolated strain JQ-H3 exhibited heterotrophic nitrification-aerobic denitrification (HN-AD) ability using poly (ε-caprolactone) (PCL) as a sole carbon source under aerobic conditions. This was the first time that a PCL-degrading bacterium was characterized to be with capability of nitrifying and denitrifying performances. Strain JQ-H3 removed approximately 95.40% of NH4+-N (102.40 mg/L), about 91.1% of NO3--N (99.01 mg/L), with the maximum specific removal rates of 0.308 mg NH4+-N/mg DCW/h and 0.220 mg NO3--N/mg DCW/h, respectively. The functional genes amoA, napA, nirS, cnorB, and nosZ were successfully expressed during the nitrogen removal process. An increasing PCL concentrations caused a decline in cell growth and nitrogen removal efficiency, which was attributed to the decrease in the rate of the PCL hydrolysis and the amount of dissolved organic carbon (DOC) release. These results demonstrated the strain as an ideal candidate for nitrogen removal from wastewater by using PCL as carbon source.

Combining YESS and TESSYS techniques during percutaneous transforaminal endoscopic discectomy for multilevel lumbar disc herniation.

The authors retrospectively characterized the clinical outcomes of combining the Yeung endoscopic spine system (YESS) and transforaminal endoscopic surgical system (TESSYS) techniques during percutaneous transforaminal endoscopic discectomy (PTED) to treat multilevel lumbar disc herniation.PTED using both YESS and TESSYS was performed on 52 patients with multilevel lumbar disc herniations who had shown no apparent response to previous conservative treatments. Postsurgical follow-ups were conducted at weeks 1, 26, and 48. Patients' preoperative and postoperative performances were assessed by modified MacNab classification, Japanese Orthopedic Association (JOA) scores, Oswestry disability index (ODI), and visual analog scale (VAS), and compared with 34 and 45 patients who were treated only by YESS and TESSYS, respectively.The postsurgery surgeon-performed assessment showed satisfactory results in 98% of the YESS + TESSYS-treated cases. The average operative time was 116 ±â€Š23 minutes, intraoperative bleeding was 19 ±â€Š12 mL, and bed stay was 3 days. No complications occurred, including infection, nerve injury, or spinal canal hematoma. One week after surgery, the modified MacNab classifications of the patients were excellent in 45, good in 6, fair in 1, and poor in 0 (98% were excellent or good). JOA, ODI, and VAS scores for low back pain significantly improved relative to the preoperative assessment (P < .01) and had remained stable at 26 and 48 weeks.PTED that combined YESS and TESSYS techniques, depending on the predominant type of lumbar disc herniation at individual levels, is safe, minimally invasive, and effective.

A Randomized Trial Comparing Clinical Outcomes Between Zero-Profile and Traditional Multilevel Anterior Cervical Discectomy and Fusion Surgery for Cervical Myelopathy.

STUDY DESIGN: Prospective randomized study from a single center OBJECTIVE.: The purpose of this study was to compare outcomes between a zero-profile (ZP) anterior cervical discectomy and fusion (ACDF) construct to a traditional ACDF with anterior cervical plate (ACP) in the treatment of multilevel cervical spondylotic myelopathy. SUMMARY OF BACKGROUND DATA: Multilevel cervical spondylotic myelopathy can be treated by a variety of techniques, most commonly with corpectomy, ACDF, posterior cervical fusion, or a combination of the three. Examples in the literature of comparative effectiveness of different anterior approach types are few. METHODS: A total of 104 patients with multilevel cervical spondylotic myelopathy were randomized in equal proportion between treated with ACDF and ZP or ACDF with ACP. Clinical efficacy of two groups was evaluated preoperatively and at all postoperative time points through 2 years postoperative by the Japanese Orthopedic Association score and the neck disability index. Radiographic changes from baseline, including disc height and cervical lordosis, were evaluated at the same postoperative time points. Complications were assessed perioperatively and through 2 years postoperatively. RESULTS: The ZP and ACP ACDF groups demonstrated substantially equivalent Japanese Orthopaedic Association, neck disability index, disc height, and lordosis improvements from baseline, which were maintained through 2 years postoperatively. Complications occurred in 4% of ZP and 17% of ACP patients (P = 0.052), and zero (0%) ZP and four (8%) ACP patients reported hoarseness or dysphagia. CONCLUSION: ZP used in multilevel ACDF may obtain favorable clinical outcomes and a lower postoperative complication. LEVEL OF EVIDENCE: 2.