Finite Element Modeling for Biomechanical Comparisons of Multilevel Transforaminal, Posterior, and Lateral Lumbar Approaches to Interbody Fusion Augmented with Posterior Instrumentation.

OBJECTIVE: Verifying the intervertebral stability of each intervertebral fusion procedure, including transforaminal, posterior, and lateral lumbar interbody fusion (TLIF, PLIF, and LLIF, respectively), and the ratio of stress on the rods and pedicle screws during initial fixation may help select a fixation procedure that reduces the risk of mechanical complications, including rod fracture and screw loosening. Thus, we aimed to assess whether these procedures could prevent mechanical complications. METHODS: Using the finite element method (FEM), we designed 4 surgical models constructed from L2-5 as follows: posterior lumbar fusion (PLF), TLIF, PLIF, and LLIF models. Bilateral rods and each pedicle screw stress were tracked and calculated as Von Mises stress (VMS) for comparison among the PLF and other 3 interbody fusion models during flexion, extension, and side-bending movements. RESULTS: The lowest rod VMS was LLIF, followed by PLIF, TLIF, and PLF in flexion and side bending movements. Compared with PLF, intervertebral fixation significantly reduced stress on the rods. No remarkable differences were observed in extension movements in each surgical procedure. A tendency for higher pedicle screw VMS was noted at the proximal and distal ends of the fixation ranges, including L2 and L5 screws for each procedure in all motions. Intervertebral fixation significantly reduced stress on the L2 and L5 screws, particularly in LLIF. CONCLUSIONS: Stress on the rods and pedicle screws in the LLIF model was the lowest compared with that induced by other intervertebral fusion procedures. Therefore, LLIF may reduce mechanical complications occurrence, including rod fracture and screw loosening.

[Evaluation of the Capacity to Produce Histamine by Histamine-Producing Bacteria during Storage at 10℃].

Histamine is produced from histidine using histidine decarboxylase of histamine-producing bacteria. However, associated histamine food poisoning demands microbiological controls. Furthermore, studies reported that histamine production by histamine-producing bacteria is affected by temperature. Therefore, to prevent histamine food poisoning, it is desirable to store foods below 4℃. However, it is challenging to maintain the storage temperature of food substances in refrigerators constantly below 4℃. Thus, we investigated histamine production capacity using seven histamine-producing bacterial strains under storage at 10℃, a more reasonable cold storage condition. Subsequently, we examined the variation of histamine production in buffers, the correlation between bacterial density and histamine production quantities, and the growth rate in broths. Results showed that similar levels of histamine were produced in buffers even after 5 days of storage under certain conditions in which histamine-producing bacteria did not grow. Moreover, bacterial density was proportional to histamine production, and the coefficient of determination was more than 0.97, and the bacterial density required to produce 200 µg/mL of histamine during storage at 10℃ was calculated to be 4×107-4×108 CFU/mL. When the initial bacterial density was 102-103 CFU/mL, psychrophilic bacteria required 2 or 3 days and mesophilic bacteria required more than 4 days to grow above 107 CFU/mL. The above results suggest that understanding the capacity of histamine-producing bacteria to produce histamine and its growth rate in foods is important for the prevention of histamine food poisoning.

Co-administration of a plasmid encoding CD40 or CD63 enhances the immune responses to a DNA vaccine against bovine viral diarrhea virus in mice.

Bovine viral diarrhea virus (BVDV) causes substantial economic losses in the livestock industry worldwide. Plasmids encoding the BVDV E2 protein are potential DNA vaccines against BVDV, but their immunogenicity has been insufficient. Here, we investigated the adjuvant effect of CD40 and CD63 plasmids on the immune responses to a BVDV E2 DNA vaccine in mice. We constructed pUMVC4a-based plasmids encoding the BVDV E2 protein (pE2), mouse CD40 (pCD40), or mouse CD63 (pCD63). Protein expression by each plasmid was confirmed through Western blot analysis and immunofluorescence staining of cultured cell lines. BALB/c mice were immunized intradermally twice with pE2 in combination with, or without, pCD40 or pCD63, with 3 weeks between the two doses. pE2 with pCD40 induced significantly higher neutralizing antibody titers against BVDV than pE2 alone. pE2 with pCD63 induced significantly higher anti-E2 IgG2a antibody titers than pE2 alone. Furthermore, pE2 with pCD40 or pCD63 induced significantly increased lymphocyte proliferation and interferon (IFN)-γ production in response to BVDV, compared with E2 alone. These results suggest that a plasmid encoding CD40 or CD63 can be used as an adjuvant to enhance immune responses to DNA vaccines against BVDV.

Comparison of the Susceptibility to Implant Failure in the Lateral, Posterior, and Transforaminal Lumbar Interbody Fusion: A Finite Element Analysis.

OBJECTIVE: There are several techniques for lumbar interbody fusion, and implant failure following lumbar interbody fusion can be troublesome. This study aimed to compare the stress in posterior implant and peri-screw vertebral bodies among lateral lumbar interbody fusion (LLIF), posterior lumbar interbody fusion (PLIF), and transforaminal lumbar interbody fusion (TLIF) and to select the technique that is least likely to cause implant failure. METHODS: We created an intact L3-L5 model and simulated the LLIF, PLIF, and TLIF techniques at L4-L5 using finite element methods. All models at the lower portion of L5 were fixed and imposed a preload of 400 N and a moment of 7.5 Nm on the upper portion of L3 to simulate flexion, extension, lateral bending, and axial rotation. We investigated the peak stresses and stress concentration in the posterior implant and peri-screw vertebral bodies for the LLIF, PLIF, and TLIF techniques. RESULTS: The extension, flexion, bending, and rotation peak stresses and stress concentration in the posterior implant, as well as the peri-screw vertebral bodies, were the lowest in LLIF, followed by PLIF and TLIF. CONCLUSIONS: It was found that implant failure was least likely to occur in LLIF, followed by PLIF and TLIF. Hence, surgeons should be aware of these factors when selecting an appropriate surgical technique and be careful for implant failure during postoperative follow-up.

Comparison of Hybrid Posterior Fixation and Conventional Open Posterior Fixation Combined with Multilevel Lateral Lumbar Interbody Fusion for Adult Spinal Deformity.

We compared radiological and clinical outcomes between multilevel lateral lumbar interbody fusion (LLIF) + hybrid posterior fixation (PF) and multilevel LLIF + conventional open PF in patients with adult spinal deformity (ASD). Patients who underwent minimally invasive surgery for ASD in a single institution between 2014 and 2018 were retrospectively reviewed. Fifty-six patients (hybrid PF, 30; open PF, 26) who underwent ASD correction surgery were enrolled between 2014 and 2018. We evaluated patients' demographics, clinical outcomes, and radiographical parameters in each group. There was significantly less estimated blood loss in the hybrid PF group (662.8 mL vs. 1088.8 mL; p = 0.012). The CRP level 7 days after surgery was significantly lower in the hybrid PF group (2.9 mg/dL vs. 4.3 mg/dL; p = 0.035). There was no significant difference between the two groups in other demographic variables, visual analog scores for back pain and leg pain, Oswestry Disability Index, coronal Cobb angle, lumbar lordosis, pelvic tilt, pelvic incidence-lumbar lordosis mismatch, and sagittal vertical axis. There was a significantly higher percentage of major complications in the open PF group (42.3% vs. 13.3%; p = 0.039). Thus, LLIF + hybrid PF for ASD corrective surgery may be comparable to LLIF + open PF in terms of clinical and radiographic outcomes.

Characterization of microRNA expression in B cells derived from Japanese black cattle naturally infected with bovine leukemia virus by deep sequencing.

Bovine leukemia virus (BLV) is the causative agent of enzootic bovine leukosis (EBL), a malignant B cell lymphoma. However, the mechanisms of BLV-associated lymphomagenesis remain poorly understood. Here, after deep sequencing, we performed comparative analyses of B cell microRNAs (miRNAs) in cattle infected with BLV and those without BLV. In BLV-infected cattle, BLV-derived miRNAs (blv-miRNAs) accounted for 38% of all miRNAs in B cells. Four of these blv-miRNAs (blv-miR-B1-5p, blv-miR-B2-5p, blv-miR-B4-3p, and blv-miR-B5-5p) had highly significant positive correlations with BLV proviral load (PVL). The read counts of 90 host-derived miRNAs (bta-miRNAs) were significantly down-regulated in BLV-infected cattle compared to those in uninfected cattle. Only bta-miR-375 had a positive correlation with PVL in BLV-infected cattle and was highly expressed in the B cell lymphoma tissue of EBL cattle. There were a few bta-miRNAs that correlated with BLV tax/rex gene expression; however, BLV AS1 expression had a significant negative correlation with many of the down-regulated bta-miRNAs that are important for tumor development and/or tumor suppression. These results suggest that BLV promotes lymphomagenesis via AS1 and blv-miRNAs, rather than tax/rex, by down-regulating the expression of bta-miRNAs that have a tumor-suppressing function, and this downregulation is linked to increased PVL.

Electrochemical Crystal Growth of Titanium Oxyfluorides-A Strategy for Development of Electron-Doped Materials.

We report on the growth of single crystals of an electron-doped titanium oxyfluoride, Li2Ti(O,F)3, employing high-temperature electrolysis of TiO2 with a eutectic Li2MoO4-LiF melt. Greenish octahedral-shaped crystals (∼30 µm in size) with a cubic rocksalt-type structure were successfully obtained by precisely tuning the applied voltage. The temperature-dependent magnetic susceptibility data revealed a paramagnetic behavior at low temperatures, ensuring the presence of Ti3+ ions (mean valence number of +3.78; F/Ti ∼ 0.15). The crystals exhibited clear visible-light absorption and produced H2 from water in the presence of a sacrificial reagent under UV-light irradiation. Li2Ti(O,F)3 more efficiently produced H2 compared with a nondoped oxyfluoride Li5Ti2O6F, likely due to the doped electrons for the former. This work highlights a promising electrochemical approach toward growing electron-doped oxyfluoride crystals.

Dynamic ionic radius of alkali metal ions in aqueous solution: a pulsed-field gradient NMR study.

The dynamic behavior of alkali metal ions, Li+, Na+, K+, Rb+ and Cs+ in aqueous solutions is one of the most important topics in solution chemistry. Since these alkali metals contain nuclear magnetic resonance (NMR) active nuclei, it is possible to directly measure the diffusion constants of the alkali metal ions using the pulsed field gradient (PFG) NMR method. In this paper, the 7Li, 23Na, 87Rb, 133Cs and 1H resonances are observed for diffusion constants in aqueous solution and the solvent H2O. Until now, the values of the diffusion constant have been lacking when discussing hydration effects around alkali metal ions. It is known that the static ionic radius (R ion) increases with increasing the atomic number, and the experimental diffusion constants also increase with increasing the atomic number, which is opposite to the Stokes-Einstein (SE) relation. It suggests that alkali metal ions diffuse through a space of 10-6 m accompanying the hydrated spheres with a time interval of 10-3 s. For each alkali metal ion, the dynamic ionic radius is evaluated.

Effectiveness of on-farm continuous flow high-temperature short-time pasteurization for inactivation of bovine leukemia virus in milk.

The effectiveness of on-farm continuous flow high-temperature short-time (HTST) pasteurization (i.e., 72°C for 15 s) for the inactivation of bovine leukemia virus (BLV) in milk was investigated with a sheep bioassay. Four sheep that had been inoculated with completely pasteurized milk containing approximately 3.4 × 107 BLV-infected peripheral blood mononuclear cells (PBMC) and treated by either HTST pasteurization or laboratory-scale low-temperature long-time (LTLT) pasteurization (i.e., 60°C for 30 min), remained negative for BLV for at least 17 weeks after inoculation. In contrast, all sheep inoculated with unpasteurized or inadequately pasteurized milk containing the same number of BLV-infected PBMC were tested positive for BLV and anti-BLV antibodies within 3 weeks after inoculation. These results suggest that on-farm continuous flow HTST pasteurization was equivalent value with inactivated BLV on the LTLT procedure and can effectively inactivate BLV in the milk. Therefore, on-farm HTST pasteurization of the pooled colostrum or milk used in automated feeding systems is likely to protect group-housed preweaned calves from BLV infection, thereby improving animal health on dairy farms.

Nationwide Survey of Infectious Bronchitis Virus on Layer Farms in Japan During 2015.

After accumulating data through a nationwide survey, we characterized the recent prevalences and geographic distributions of various genotypes of infectious bronchitis virus (IBV) on layer farms in Japan. Reverse transcription PCR analysis of fecal samples revealed the presence of the IBV nucleoprotein (N) gene on approximately 30% of the farms surveyed. N-gene detection rates were higher in the Chugoku and Kyushu regions than in the remaining surveyed regions. Phylogenetic analysis of S1 gene sequences revealed that JP-I, JP-II, JP-III, and Massachusetts genotypes were particularly prevalent, with JP-I isolated throughout the country. Additionally, JP-II was the genotype detected most frequently in Chugoku, and JP-III was the most frequent in Kyushu. Unlike the previous results obtained in 1998 through 2003, the European-prevalent 4/91 genotype was no longer circulating in Japan. Moreover, the number of prefectures where multiple genotypes were detected simultaneously increased during that time.

Nota de Investigación- Muestreo nacional en Japón de los virus de la bronquitis infecciosa en granjas de postura durante el año 2015. Después de acumular datos a través de un muestreo a nivel nacional, se caracterizaron las prevalencias recientes y las distribuciones geográficas de varios genotipos del virus de la bronquitis infecciosa (IBV) en granjas de gallinas de postura en Japón. El análisis mediante transcripción reversa y PCR de muestras fecales reveló la presencia del gene de la nucleoproteína (N) del virus de la bronquitis infecciosa en aproximadamente el 30% de las granjas muestreadas. Las tasas de detección del gene N fueron más altas en las regiones de Chugoku y Kyushu en comparación con las regiones encuestadas restantes. El análisis filogenético de las secuencias del gene S1 reveló que los genotipos JP-I, JP-II, JP-III y Massachusetts eran particularmente prevalentes, siendo JP-I el genotipo aislado en todo el país. Además, JP-II fue el genotipo detectado con mayor frecuencia en Chugoku, y el genotipo JP-III fue el más frecuente en Kyushu. A diferencia de los resultados anteriores obtenidos desde el año 1998 hasta el 2003, el genotipo 4/91 prevalente en Europa ya no circulaba en Japón. Además, el número de prefecturas donde se detectaron de manera simultánea múltiples genotipos aumentó durante ese tiempo.

Quantification of metal-induced susceptibility artifacts associated with ultrahigh-field magnetic resonance imaging of spinal implants.

Reports on spinal-implant metallic artifacts in 7-T magnetic resonance imaging (MRI) are lacking. Thus, we investigated the magnitude of metal artifacts derived from spinal implants in 7-T MRI and analyzed the differences obtained with spinal rods manufactured from pure titanium, titanium alloy, and cobalt-chrome (5.5-mm and 6.0-mm diameters and 50-mm length). Following the American Society for Testing and Materials guidelines, we measured the artifact size and artifact volume ratio of each rod during image acquisition using 7-T MRI scanners with three-dimensional (3D) T1-weighted and 3D T2* spoiled gradient echo (GRE), 3D T2-weighted fast spin echo, zero echo time (ZTE), and diffusion-weighted imaging sequences. Pure titanium and titanium alloy rods yielded significantly smaller artifacts than did cobalt-chrome rods, with no significant difference between pure titanium and titanium alloy rods. The artifact sizes of the 5.5-mm and 6.0-mm diameter rods were similar. The artifact magnitude increased in the following sequence order: ZTE, 3D T2 fast spin echo, 3D T1 spoiled GRE, 3D T2* spoiled GRE, and diffusion-weighted imaging. Artifacts obtained using the spin echo method were smaller than those obtained with the GRE method. Because the echo time in ZTE is extremely short, the occurrence of artifacts because of image distortion and signal loss caused by differences in magnetic susceptibility is minimal, resulting in the smallest artifacts. ZTE can be a clinically useful method for the postoperative evaluation of patients after instrumentation surgery, even with 7-T MRI.

Efficient luminescent properties and cation recognition ability of heavy group 13 element complexes of N2O2- and N2O4-type dipyrrins.

The first mononuclear 1 : 1 complexes of heavy group 13 elements (Ga and In) and N2O2/N2O4-type dipyrrins were synthesized and characterized. The N2O2-type complexes showed efficient luminescent properties even in polar solvents. The N2O4-type complexes exhibited fluorometric responses to alkaline earth metal ions.

Two-step template method for synthesis of axis-length-controlled porphyrin-containing hollow structures.

π-Conjugated porphyrin-containing hollow structures with defined axis-length were successfully synthesized by a two-step template method, i.e., template-assisted cyclization and oligomerization. During the oligomerization, templates played important roles in controlling the reaction rates and the axis lengths. The hollow structures exhibited an extended effective π-conjugation because of the high coplanarity between porphyrins.

Evaluation of the serum ionic fluoride concentration as a biomarker of bone metabolism post-spinal fusion surgery.

BACKGROUND: Bone union after spinal fusion surgery with instrumentation has been determined only with imaging studies. We evaluated the usefulness of the serum ionic fluoride (SIF) concentration as a biomarker of the bone union status. METHODS: We enrolled 25 patients who underwent spinal surgery in our institution, and we divided patients into three groups with and without instrumentation (G1, G2, and G3). We collected the fasting serum level preoperatively and on day 1 (D1), week 1 (D7), week 2 (D14), month 1 (D30), month 3 (D90), and month 6 (D180) postoperatively, and measured SIF concentrations using the flow injection method with an ion-selective electrode. RESULTS: Although preoperative SIF concentrations were similar among the 3 groups, postoperative SIF concentrations were different among the groups. SIF concentrations in groups with instrumentation (G2 and G3) increased between D14 and D90 postoperatively and decreased at D180 postoperatively. SIF concentrations in the group without instrumentation (G1) decreased between D30 and D180 postoperatively. CONCLUSIONS: An SIF concentration that is higher postoperatively than preoperatively may indicate unstable bone union, whereas a lower SIF concentration postoperatively than preoperatively may indicate stable bone union. We concluded that the SIF concentration may be useful for diagnosing bone union.

Hetero Face-to-Face Porphyrin Array with Cooperative Effects of Coordination and Host-Guest Complexation.

We successfully synthesized a hetero face-to-face porphyrin array composed of ZnTPP and RuTPP(DABCO)2 (TPP: 5, 10, 15, 20-tetraphenylporphyrin, DABCO: 1,4-diazabi-cyclo[2.2.2]octane) in 2:1 molar ratio. A cyclic Zn porphyrin dimer (ZnCP) was also used as the host molecule for the Ru porphyrin. In the latter, the Ru-DABCO bonding in RuTPP(DABCO)2 was stabilized by the host-guest complexation. Reaction progress kinetic analysis of the ligand substitution reaction of RuTPP(DABCO)2 and that in ZnCP revealed the stabilization mechanism of the Ru-DABCO bonding. Photoinduced electron transfer (PET) from the Zn porphyrin to the Ru porphyrin was observed in the porphyrin array. The host-guest stabilization of unstable complex for construction of a donor-acceptor-donor structure is expected to be a new method for an artificial photosynthesis.

Dynamics of different bacterial communities are capable of generating sustainable electricity from microbial fuel cells with organic waste.

The relationship between the bacterial communities in anolyte and anode biofilms and the electrochemical properties of microbial fuel cells (MFCs) was investigated when a complex organic waste-decomposing solution was continuously supplied to MFCs as an electron donor. The current density increased gradually and was maintained at approximately 100 to 150 mA m(-2). Polarization curve analyses revealed that the maximum power density was 7.4 W m(-3) with an internal resistance of 110 Ω. Bacterial community structures in the organic waste-decomposing solution and MFCs differed from each other. Clonal analyses targeting 16S rRNA genes indicated that bacterial communities in the biofilms on MFCs developed to specific communities dominated by novel Geobacter. Multidimensional scaling analyses based on DGGE profiles revealed that bacterial communities in the organic waste-decomposing solution fluctuated and had no dynamic equilibrium. Bacterial communities on the anolyte in MFCs had a dynamic equilibrium with fluctuations, while those of the biofilm converged to the Geobacter-dominated structure. These bacterial community dynamics of MFCs differed from those of control-MFCs under open circuit conditions. These results suggested that bacterial communities in the anolyte and biofilm have a gentle symbiotic system through electron flow, which resulted in the advance of current density from complex organic waste.

Differential epigenetic regulation of BDNF and NT-3 genes by trichostatin A and 5-aza-2'-deoxycytidine in Neuro-2a cells.

To understand epigenetic regulation of neurotrophins in Neuro-2a mouse neuroblastoma cells, we investigated the alteration of CpG methylation of brain-derived neurotrophic factor (BDNF) promoter I and neurotrophin-3 (NT-3) promoter IB and that of histone modification in Neuro-2a cells. Bisulfite genomic sequencing showed that the CpG sites of BDNF promoter I were methylated in non-treated Neuro-2a cells and demethylated following 5-aza-2'-deoxycytidine (5-aza-dC) treatment. In contrast, methylation status of the NT-3 promoter IB did not change by 5-aza-dC treatment in Neuro-2a cells. Furthermore, we demonstrated that BDNF exon I-IX mRNA was induced by trichostatin A (TSA) treatment. However, NT-3 exon IB-II mRNA was not induced by TSA treatment. Chromatin immunoprecipitation assays showed that the levels of acetylated histones H3 and H4 on BDNF promoter I were increased by TSA. These results demonstrate that DNA methylation and/or histone modification regulate BDNF gene expression, but do not regulate NT-3 gene expression in Neuro-2a cells.

Robust stimulation of TrkB induces delayed increases in BDNF and Arc mRNA expressions in cultured rat cortical neurons via distinct mechanisms.

In cultures of rat cortical neurons, we found that stimulation of tyrosine receptor kinase B (TrkB) with brain-derived neurotrophic factor (BDNF) induced a biphasic expression of BDNF exon IV-IX mRNA, which became obvious 1-3 h (primary induction) and 24-72 h (delayed induction) after the stimulation, and characterized the delayed induction in relation to the mRNA expression of activity-regulated cytoskeleton-associated protein (Arc). Withdrawal of BDNF from the medium after stimulation for 3 h allowed the delayed induction, which was caused at the transcriptional level and dependent upon the initial contact between exogenously added BDNF and TrkB, the effect of which was time- and dose-dependent. The primary induction was controlled by the extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK) whereas the secondary induction by the calcium (Ca(2+)) signaling pathway. The enhanced Arc or Zif268 mRNA expression was controlled by activation of the ERK/MAPK pathway, both of which were repressed by blocking the binding of endogenously synthesized BDNF to TrkB. Thus, robust stimulation of TrkB autonomously induces delayed BDNF mRNA expression in an activity-dependent manner in rat cortical neurons, resulting in the stimulation of Arc mRNA expression through endogenously synthesized BDNF, the process being orchestrated by the Ca(2+) and ERK/MAPK signaling pathways.