The segment-dependent changes in lumbar intervertebral space height during flexion-extension motion

Objectives

Many studies have investigated the kinematics of the lumbar spine and the morphological features of the lumbar discs. However, the segment-dependent immediate changes of the lumbar intervertebral space height during flexion-extension motion are still unclear. This study examined the changes of intervertebral space height during flexion-extension motion of lumbar specimens.

Methods

First, we validated the accuracy and repeatability of a custom-made mechanical loading equipment set-up. Eight lumbar specimens underwent CT scanning in flexion, neural, and extension positions by using the equipment set-up. The changes in the disc height and distance between adjacent two pedicle screw entry points (DASEP) of the posterior approach at different lumbar levels (L3/4, L4/5 and L5/S1) were examined on three-dimensional lumbar models, which were reconstructed from the CT images.

Results

All the vertebral motion segments (L3/4, L4/5 and L5/S1) had greater changes in disc height and DASEP from neutral to flexion than from neutral to extension. The change in anterior disc height gradually increased from upper to lower levels, from neutral to flexion. The changes in anterior and posterior disc heights were similar at the L4/5 level from neutral to extension, but the changes in anterior disc height were significantly greater than those in posterior disc height at the L3/4 and L5/S1 levels, from neutral to extension.

Conclusions

The lumbar motion segment showed level-specific changes in disc height and DASEP. The data may be helpful in understanding the physiologic dynamic characteristics of the lumbar spine and in optimising the parameters of lumbar surgical instruments.

Cite this article: M. Fu, Q. Ye, C. Jiang, L. Qian, D. Xu, Y. Wang, P. Sun, J. Ouyang. The segment-dependent changes in lumbar intervertebral space height during flexion-extension motion. Bone Joint Res 2017;6:245–252. DOI: 10.1302/2046-3758.64.BJR-2016-0245.R1.

Spontaneous wormlike micelles formed in a single-tailed zwitterionic surface-active ionic liquid aqueous solution

Wormlike micelles were successfully fabricated by the self-assembly of a single-tailed zwitterionic surface-active ionic liquid (SAIL), 3-(1-hexadecyl-3-imidazolio) propanesulfonate β-naphthalene sulfonate (C₁₆IPS-Nsa), in aqueous solutions without any additives. With increasing zwitterionic SAIL concentration, spontaneous transition from micelles to wormlike micelles and then a hexagonal phase occurs. Interestingly, the wormlike micelles are closed, stretched and directionally arranged, which was rarely found in previous research studies. This kind of wormlike micelle is useful to serve as novel soft template in the synthesis of functional materials. ¹H NMR illustrated that the introduced π-π stacking and hydrophobic interactions originated from the hydrophobic aromatic counterions are responsible for the structural transformation. Density functional theory (DFT) simulated the optimum configuration of C₁₆IPS-Nsa and calculated the interaction energy of C₁₆IPS-Nsa-H₂O is 39.6 kJ mol^-1. This work paves the way for regulating the self-assembly structures of amphiphiles through changing specific weak interactions.

[Preventive and therapeutic effects of rapamycin against autoimmune hepatitis and liver fibrosis and possible mechanisms]

OBJECTIVE

To investigate the preventive and therapeutic effects of rapamycin (RAPA) on autoimmune hepatitis and liver fibrosis induced by concanavalin A (ConA) and possible mechanisms.

METHODS

Female C57BL/6 mice aged 8 weeks were randomly divided into normal control group, ConA model group, and ConA+RAPA treatment group. The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured; hematoxylin-eosin and Masson staining and Knodell HAI and Ishak scoring systems were used to evaluate the degrees of liver inflammation and fibrosis. Gradient centrifugation was used to separate mononuclear cells, flow cytometry was used to measure CD4(+)/CD8(+) ratio, and intracellular cytokine staining was performed to measure the levels of interferon-γ (IFN-γ), interleukin-4 (IL-4), interleukin-10 (IL-10), and transforming growth factor β (TGF-β) in immune cells. The t-test was used for data comparison between groups.

RESULTS

The RAPA treatment group showed a significant reduction in serum ALT level compared with the ConA model group (P < 0.05). Liver inflammatory injury was reduced significantly, and there was no obvious fibrous tissue proliferation. The level of TGF-β in mononuclear cells was reduced significantly, and the treatment group had a significantly lower level of TGF-β than the model group (8.91%±1.25% vs 16.65%±2.05%, P < 0.05). The proportions of CD4(+) and CD8(+)T cells in the liver were reduced, and the treatment group had significantly lower proportions of CD4(+) and CD8(+)T cells than the model group (proportion of CD4(+)T cells: 4.09%±1.20% vs 8.91%±0.69%, P < 0.05; proportion of CD8(+)T cells: 3.28%±0.66% vs 9.68%±1.46%, P < 0.05). The proportion of Th1 cells was reduced, and the treatment group had a significantly lower proportion of Th1 cells than the model group (1.02%±0.06% vs 2.83%±0.21%, P < 0.05); the proportions of Th3 and Tr1 regulatory T cells were increased, and the treatment group had significantly higher proportions of Th3 and Tr1 regulatory T cells than the model group (proportion of Th3 regulatory T cells: 59.53%±9.82% vs 47.13%±4.79%, P < 0.05; proportion of Tr1 regulatory T cells: 10.63%±2.27% vs 7.09%±1.66%, P < 0.05), but the proportion of Th2 cells showed no significant difference between the two groups (P > 0.05).

CONCLUSION

RAPA can promote the differentiation of Th3/Tr1 cells, reduce the expression of TGF-β in mononuclear cells, slow down the progression of chronic hepatitis induced by ConA into liver fibrosis, and thus prevent liver fibrosis.

Does adjuvant radiation therapy benefit women with small mammography-detected breast cancers?

BACKGROUND

Women with small nonpalpable breast tumours have an excellent prognosis. The benefit of radiotherapy in this group of low-risk women is unknown.

METHODS

A cohort of 1595 women with stages i-iii invasive breast cancer treated with breast-conserving surgery were followed for local recurrence. Using t-tests, baseline demographic data and tumour characteristics were compared for the women who had palpable (n = 1023) and mammography-detected (n = 572) breast cancers. The 15-year actuarial risk of local recurrence was estimated using a Kaplan-Meier method, stratified for adjuvant radiation therapy (yes or no), tumour palpability (palpable or not), and tumour size (≤1 cm or >1 cm). Hazard ratios (hrs) and 95% confidence intervals (95% cis) were calculated using a multivariate Cox regression model. Results were considered statistically significant if 2-tailed p values were less than 0.05.

RESULTS

Among women with a nonpalpable tumour, the 15-year actuarial rates of local recurrence were, respectively, 13.9% and 18.3% for those treated and not treated with adjuvant radiation therapy (hr: 0.65; 95%ci: 0.40 to 1.06; p = 0.08). Among women with small nonpalpable breast cancers (≤1.0 cm), the rates were 14.6% and 13.4% respectively (p = 0.67). The absolute reduction in 15-year local recurrence was 11.0% for women with palpable tumours.

CONCLUSIONS

Our results suggest that women with small (<1 cm) screen-detected nonpalpable breast cancers likely derive little benefit from adjuvant radiotherapy; however, an adequately powered randomized trial would be required to make definitive conclusions.

Abstract P5-09-01: Plasma osteoprotegerin and the risk of breast cancer in BRCA1 and BRCA2 mutation carriers

This abstract was withdrawn by the authors.

One-Pot Solvothermal in Situ Growth of 1D Single-Crystalline NiSe on Ni Foil as Efficient and Stable Transparent Conductive Oxide Free Counter Electrodes for Dye-Sensitized Solar Cells

One-dimensional single-crystal nanostructural nickel selenides were successfully in situ grown on metal nickel foils by two simple one-step solvothermal methods, which formed NiSe/Ni counter electrodes (CEs) for dye-sensitized solar cells (DSSCs). The nickel foil acted as the nickel source in the reaction process, a supporting substrate, and an electron transport "speedway". Electrochemical testing indicated that the top 1D single-crystal NiSe exhibited prominent electrocatalytic activity for I₃^- reduction. Due to the metallic conductivity of Ni substrate and the outstanding electrocatalytic activity of single-crystal NiSe, the DSSC based on a NiSe/Ni CE exhibited higher fill factor (FF) and larger short-circuit current density (J_sc) than the DSSC based on Pt/FTO CE. The corresponding power conversion efficiency (6.75%) outperformed that of the latter (6.18%). Moreover, the NiSe/Ni CEs also showed excellent electrochemical stability in the I^-/I₃^- redox electrolyte. These findings indicated that single-crystal NiSe in situ grown on Ni substrate was a potential candidate to replace Pt/TCO as a cheap and highly efficient counter electrode of DSSC.

Controllable hierarchical self-assembly of gemini supra-amphiphiles: the effect of spacer length

Gemini supra-amphiphiles with different spacer lengths, [M-n-M]²⁺@2[DBS]^- (n = 2, 6, 10), were easily constructed. The conformational flexibility and hydrophobicity of the spacer group can be effectively tailored through regulating the spacer length, leading to the fine control of the topologies and subsequent hierarchical self-assemblies of [M-n-M]²⁺@2[DBS]^-. Vesicles are primarily fabricated by [M-n-M]²⁺@2[DBS]^-, and then successively fused into vesicle clusters, nanotubes, and planar bilayers, whose bilayer curvatures are gradually decreased, with increasing spacer length. Coating [M-10-M]²⁺ with β-CD can reduce the flexibility and hydrophobicity of the decyl spacer, resulting in the reversion from planar bilayers to vesicles. Furthermore, stable aqueous two-phase systems (ATPSs) that spontaneously formed via vesicle fusion in the solutions of [M-n-M]²⁺@2[DBS]^- (n = 6, 10) can act as functional supramolecular systems in the isolation and purification of oil-soluble biomaterials.

[Occupational hazard risk assessment of workers exposed to benzene in a petrochemical enterprise in Shanghai, China]

Objective: To investigate the exposure to benzene, methylbenzene, and dimethylbenzene in workers in a petrochemical enterprise in Shanghai, China, and to conduct occupational hazard risk assessment. Methods: The environmental monitoring data on benzene series in the workplace of this petrochemical enterprise from 2010 to 2014 were collected, as well as workers' general status. The inhalation risk assessment model developed by United States Environmental Protection Agency (EPA) was used for risk assessment to determine the occupational hazard risk level of benzene, methylbenzene, and dimethylbenzene. Results: The pass rate of the monitoring concentration of benzene, methylbenzene, and dimethylbenzene in the workplace of this petrochemical enterprise was 100%. The results of the EPA model showed that benzene had a high carcinogenic risk, benzene and dimethylbenzene had a high non-carcinogenic risk, and methylbenzene had a low non-carcinogenic risk. Conclusion: The workers exposed to benzene in this petrochemical enterprise have a high health risk, and the EPA model can be used for occupational hazard risk assessment in chemical industry.

Photoresponsive Self-Assembly of Surface Active Ionic Liquid

A novel photoresponsive surface active ionic liquid (SAIL) 1-(4-methyl azobenzene)-3-tetradecylimidazolium bromide ([C14mimAzo]Br) with azobenzene located in the headgroup was designed. Reversible vesicle formation and rupture can be finely controlled by photostimuli without any additives in the aqueous solution of the single-tailed ionic liquid. The photoisomerization of the azobenzene derivative was investigated by (1)H NMR and UV-vis spectroscopy. Density functional theory (DFT) calculations further demonstrate that trans-[C14mimAzo]Br has less negative interaction energy, which is beneficial to aggregate formation in water. The incorporation of trans-azobenzene group increases the hydrophobicity of the headgroup and reduces the electrostatic repulsion by delocalization of charge, which are beneficial to the formation of vesicles. However, the bend of cis-azobenzene makes the cis-isomers have no ability to accumulate tightly, which induces the rupture of vesicles. Our work paves a convenient way to achieve controlled topologies and self-assembly of single SAIL.

DNA-fueled molecular machine for label-free and non-enzymatic ultrasensitive detection of telomerase activity

Herein, a non-enzymatic and label-free strategy based on DNA-fueled molecular machine was developed for ultrasensitive detection of telomerase activity in cancer cell extracts even at the single-cell level.

TRI6 and TRI10 play different roles in the regulation of deoxynivalenol (DON) production by cAMP signalling in Fusarium graminearum

The biosynthesis of mycotoxin deoxynivalenol (DON) in Fusarium graminearum is regulated by two pathway-specific transcription factors Tri6 and Tri10 and affected by various host and environmental factors. In this study, we showed that cyclic adenosine monophosphate (cAMP) treatment induced DON production by stimulating TRI gene expression and DON-associated cellular differentiation in F. graminearum. Interestingly, exogenous cAMP had no effects on the tri6 mutant but partially recovered the defect of tri10 mutant in DON biosynthesis. Although the two cAMP phosphodiesterase genes PDE1 and PDE2 had overlapping functions in vegetative growth, conidiation, sexual reproduction and plant infection, deletion of PDE2 but not PDE1 activated intracellular PKA activities and increased DON production. Whereas the tri6 pde2 mutant failed to produce DON, the tri10 pde2 double mutant produced a significantly higher level of DON than the tri10 mutant. Cellular differentiation associated with DON production was stimulated by exogenous cAMP or deletion of PDE2 in both tri10 and tri6 mutants. These data indicate that TRI6 is essential for the regulation of DON biosynthesis by cAMP signalling but elevated PKA activities could partially bypass the requirement of TRI10 for TRI gene-expression and DON production, and Pde2 is the major cAMP phosphodiesterase to negatively regulate DON biosynthesis in F. graminearum.

The squaramide-catalyzed asymmetric Michael/cyclization tandem reaction for the synthesis of chiral trifluoromethylated hydroxyimino tetrahydrobenzofuranones

An enantioselective synthesis of trifluoromethylated hydroxyimino tetrahydrobenzofuranones has been developed. 1,3-Dicarbonyl carbocyclic compounds react with β-CF3-β-disubstituted nitroalkenes in the presence of a chiral squaramide catalyst, providing efficient access to diverse hydroxyimino tetrahydrobenzofuranones featuring a trifluoromethyl group at the C3-position of an all-carbon quaternary stereocenter with good yields (up to 81%) and enantioselectivities (up to 89% ee).

Deletion of the BAC sequences from recombinant meq-null Marek's disease (MD) virus increases immunosuppression while maintaining protective efficacy against MD

Marek's disease virus (MDV) GX0101 is a field strain of MDV with a naturally occurring insertion of the reticuloendotheliosis virus (REV) long terminal repeat (LTR) fragment. Both copies of the meq gene were knocked out in the GX0101 bacterial artificial chromosome (BAC) clone to construct the recombinant virus SC9-1, resulting in a complete lack of pathogenicity and providing better protection against MD than CVI988/Rispens. In the present study, the BAC sequences in SC9-1 were removed using a cre-loxP system, and the virus termed SC9-2. SC9-2 showed a significant increase in replication in vitro and in vivo. There was a significant decrease in chicken weight, immune organ index, and antibody levels compared with those of SC9-1-inoculated chickens. The immune protection index of SC9-2 was similar to that of SC9-1, and the difference was not significant. The results of our studies demonstrate that the SC9-2 virus provides protection in specific pathogen free (SPF) chickens when challenged with a very virulent MDV rMd5, but it induces immunosuppressive effects in SPF chickens.

Aggregation behavior of zwitterionic surface active ionic liquids with different counterions, cations, and alkyl chains

The effects of anionic type, cationic structure and alkyl chain length are illustrated to regulate the self-assembly of zwitterionic SAILs.

Synthesis of porous Al doped ZnO nanosheets with high adsorption and photodecolorizative activity and the key role of Al doping for methyl orange removal

Porous Al doped ZnO (AZO) nanosheets have been prepared as an efficient multifunctional water treatment material.

Effect of the bis-imidazolium-based poly(ionic liquid) on the microstructure and the properties of AAEMs based on polyvinyl alcohol

The conductivity of AAEMs can be improved by building the ionic channel based on bis-imidazolium-based poly(ionic liquid).

Nanostructured proton-conducting membranes based on polymerizable zwitterionic ionic liquid microemulsions

Polymerizable zwitterionic ionic liquid microemulsions were fabricated for the first time to prepare ionic liquid based proton-conductors.

Prevalence of hepatitis A viral RNA and antibodies among Chinese blood donors

Like other developing countries, China was reported to have a relatively high seroprevalence of anti-hepatitis A antibodies (anti-HAV). However, no studies have evaluated the prevalence of anti-HAV and HAV RNA among voluntary blood donors with or without elevated serum alanine transaminase (ALT) levels. Anti-HAV antibodies were detected using an enzyme-linked immunosorbent assay, and reverse transcription quantitative polymerase chain reaction was carried out for detection of HAV RNA. In the current study, we analyzed a total of 450 serum samples with elevated ALT levels (≥40 U/L) and 278 serum samples with non-elevated ALT levels. Seroprevalence rates of anti-HAV were 51.6% in donors with elevated ALT and 41.4% in donors with non-elevated ALT; however, none of the samples was positive for HAV RNA. The results of our study showed lower seroprevalence rates of anti-HAV in blood donors (irrespective of ALT levels) than those in published data on Chinese populations. Although donors with elevated ALT had statistically higher prevalence rates of anti- HAV than did those with non-elevated ALT, none of the serum samples had detectable levels of the active virus. In conclusion, our results demonstrate that the transmission of hepatitis A by blood transfusion will occur rarely.