Multicolor fluorescent imaging by space-constrained computational spectral imaging

Spectral imaging is a powerful technique used to simultaneously study multiple fluorophore labels with overlapping emissions. Here, we present a computational spectral imaging method, which uses sample spatial fluorescence information as a reconstruction constraint. Our method addresses both the under-sampling issue of compressive spectral imaging and the low throughput issue of scanning spectral imaging. With simulated and experimental data, we have demonstrated the reconstruction precision of our method in two and three-color imaging. We have experimentally validated this method for differentiating cellular structures labeled with two red-colored fluorescent proteins, tdTomato and mCherry, which have highly overlapping emission spectra. Our method has the advantage of totally free wavelength choice and can also be combined with conventional filter-based sequential multi-color imaging to further improve multiplexing capability.

Abstract OT2-01-01: Not presented

This abstract was not presented at the conference.

Citation Format: Yang B, Wu J. Not presented [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-01-01.

Numerical Simulations of Realistic Lead Trajectories and an Experimental Verification Support the Efficacy of Parallel Radiofrequency Transmission to Reduce Heating of Deep Brain Stimulation Implants during MRI

Patients with deep brain stimulation (DBS) implants may be subject to heating during MRI due to interaction with excitatory radiofrequency (RF) fields. Parallel RF transmit (pTx) has been proposed to minimize such RF-induced heating in preliminary proof-of-concept studies. The present work evaluates the efficacy of pTx technique on realistic lead trajectories obtained from nine DBS patients. Electromagnetic simulations were performed using 4- and 8-element pTx coils compared with a standard birdcage coil excitation using patient models and lead trajectories obtained by segmentation of computed tomography data. Numerical optimization was performed to minimize local specific absorption rate (SAR) surrounding the implant tip while maintaining spatial homogeneity of the transmitted RF magnetic field (B₁⁺), by varying the input amplitude and phase for each coil element. Local SAR was significantly reduced at the lead tip with both 4-element and 8-element pTx (median decrease of 94% and 97%, respectively), whereas the median coefficient of spatial variation of B₁⁺ inhomogeneity was moderately increased (30% for 4-element pTx and 20% for 8-element pTx) compared to that of the birdcage coil (17%). Furthermore, the efficacy of optimized 4-element pTx was verified experimentally by imaging a head phantom that included a wire implanted to approximate the worst-case lead trajectory for localized heating, based on the simulations. Negligible temperature elevation was observed at the lead tip, with reasonable image uniformity in the surrounding region. From this experiment and the simulations based on nine DBS patient models, optimized pTx provides a robust approach to minimizing local SAR with respect to lead trajectory.

Numerical Simulations of Realistic Lead Trajectories and an Experimental Verification Support the Efficacy of Parallel Radiofrequency Transmission to Reduce Heating of Deep Brain Stimulation Implants during MRI

Patients with deep brain stimulation (DBS) implants may be subject to heating during MRI due to interaction with excitatory radiofrequency (RF) fields. Parallel RF transmit (pTx) has been proposed to minimize such RF-induced heating in preliminary proof-of-concept studies. The present work evaluates the efficacy of pTx technique on realistic lead trajectories obtained from nine DBS patients. Electromagnetic simulations were performed using 4- and 8-element pTx coils compared with a standard birdcage coil excitation using patient models and lead trajectories obtained by segmentation of computed tomography data. Numerical optimization was performed to minimize local specific absorption rate (SAR) surrounding the implant tip while maintaining spatial homogeneity of the transmitted RF magnetic field (B₁⁺), by varying the input amplitude and phase for each coil element. Local SAR was significantly reduced at the lead tip with both 4-element and 8-element pTx (median decrease of 94% and 97%, respectively), whereas the median coefficient of spatial variation of B₁⁺ inhomogeneity was moderately increased (30% for 4-element pTx and 20% for 8-element pTx) compared to that of the birdcage coil (17%). Furthermore, the efficacy of optimized 4-element pTx was verified experimentally by imaging a head phantom that included a wire implanted to approximate the worst-case lead trajectory for localized heating, based on the simulations. Negligible temperature elevation was observed at the lead tip, with reasonable image uniformity in the surrounding region. From this experiment and the simulations based on nine DBS patient models, optimized pTx provides a robust approach to minimizing local SAR with respect to lead trajectory.

Clinical and genetic features of Chinese patients with lichen and macular primary localized cutaneous amyloidosis

BACKGROUND

Primary localized cutaneous amyloidosis (PLCA) is a chronic pruritic skin disorder. The genetic basis of familial (f)PLCA involves mutations in the oncostatin M receptor (OSMR) and interleukin-31 receptor A (IL31RA) genes, but the disease pathophysiology is not fully understood.

AIM

To investigate the OSMR mutation spectrum in patients with sporadic (s)PLCA/fPLCA, lichen/macular PLCA in mainland China.

METHODS

This study was carried out on 64 patients with sPLCA, along with 36 with fPLCA and 10 unaffected individuals collected from 23 unrelated Chinese families. Genomic DNA was extracted from peripheral blood samples. Mutation screening of 17 OSMR exons was performed by Sanger sequencing.

RESULTS

PLCA lesions are typically localized to the shins, forearm and back. Sequence analysis of OSMR exons demonstrated that the OSMR missense mutation rate in patients with fPLCA (63.89%) was significantly higher than that in patients with sPLCA (34.38%). The male/female ratio of patients carrying a homozygous OSMR mutation (0.29) was significantly lower than that of patients carrying a heterozygous OSMR mutation (1.08; P < 0.05) and of patients with wildtype OSMR (1.75; P < 0.01). Age of onset of PLCA with OSMR homozygous mutation (median age 20 years) was earlier than that of PLCA with OSMR heterozygous mutation (median age 32 years; P < 0.01) or PLCA with wildtype genotype (median age 32 years; P < 0.01).

CONCLUSION

The present data indicate OSMR mutations as not only the main cause of fPLCA, but also the potential source of the pathogenesis of sPLCA, although the exact molecular mechanism remains unknown.

Impact of lactic acid fermentation on acids, sugars, and phenolic compounds in black chokeberry and sea buckthorn juices

The aim of this research was to study the potential of malolactic fermentation to modify the composition of the juices of sea buckthorn, chokeberry and lingonberry. Juices were prepared with and without pectinolytic enzyme treatment, followed by fermentation with commercially available strains of Lactobacillus plantarum, originally isolated from fermented plant materials. The juices before and after the fermentation were analyzed with GC-FID, HPLC-DAD, and HPLC-MS. Enzyme treatment significantly increased the phenolic content in the juices by 11-50%. None of strains showed ability to ferment lingonberry juice. On the other hand, L. plantarum DSM 10492 and DSM 20174 converted all malic acid to lactic acid in sea buckthorn and chokeberry juices, respectively. Fermentation with DSM 10492 reduced the content of flavonols by 9-14% and hydroxycinnamic acids by 20-24% in chokeberry juice. Flavonol glycosides and sugars in sea buckthorn as well as anthocyanins in chokeberry remained unaffected by the fermentation.

[Protective effects and mechanism of keratinocyte growth factor combined with hypoxia inducible factor-1α on intestinal crypt epithelial cells of rats with hypoxia stress]

Objective: To investigate the protective effects and mechanism of keratinocyte growth factor (KGF) combined with hypoxia inducible factor-1α (HIF-1α) on intestinal crypt epithelial cells (IEC-6) of rats with hypoxia stress. Methods: (1) The routinely cultured IEC-6 of rats were collected and divided into normoxia blank group, normoxia KGF group, normoxia HIF-1α group, and normoxia combine group, according to the random number table, and then the previous mediums were respectively replaced with dulbecco's modified eagle medium (DMEM), medium with 0.5 ng/mL KGF, medium with 10.0 ng/mL HIF-1α, and medium with 0.5 ng/mL KGF and 30.0 ng/mL HIF-1α. And the cells were cultured in cell incubator with oxygen volume fraction of 21% for 24 hours. (2) Another batch of routinely cultured IEC-6 were collected and divided into normoxia control group, hypoxia control group, hypoxia KGF group, hypoxia HIF-1α group, and hypoxia combine group, according to the random number table. The previous mediums were replaced with DMEM, DMEM, medium with 0.5 ng/mL KGF, medium with 10.0 ng/mL HIF-1α, and medium with 0.5 ng/mL KGF and 30.0 ng/mL HIF-1α respectively. And then, the cells in normoxia control group were cultured routinely for 24 hours, and cells in the other 4 groups were cultured in cells incubator of 3 gases, with oxygen volume fraction of 5% for 24 hours. Cells cultured in normoxic and hypoxic incubators were collected, with 3 samples in each group, and morphological changes of cells were observed with optical microscope. Cells cultured in normoxic and hypoxic incubators were collected, with 3 samples in each group, and survival rates of cells were detected by cell count kit 8. Cells in normoxia control group and cells cultured in hypoxic incubator were collected, with 3 samples in each group. The cell cycle changes and apoptosis rates were detected by flow cytometer, the content of adenosine triphosphate (ATP) was detected by ultraviolet spectrophotometer, and protein expression of p53 was detected by Western blotting. Data were processed with one-way analysis of variance and least significant difference test. Results: (1) After being cultured for 24 h, cells cultured in normoxic incubator grew well with oval or round shapes and clear cytoplasm, and cells cultured in hypoxic incubator showed irregular shapes such as fusiform or starlike shape, with black particle in cytoplasm. (2) After being cultured for 24 h, cell survival rates of normoxia blank group, normoxia KGF group, normoxia HIF-1α group, and normoxia combine group were (107.4±8.7)%, (109.8±2.9)%, (115.8±7.4)%, and (112.8±10.6)% respectively. There was no significantly statistical difference in general comparison of cell survival rates among the above groups (F=0.685, P=0.586). After being cultured for 24 h, cell survival rates of hypoxia control group, hypoxia KGF group, hypoxia HIF-1α group, and hypoxia combine group were (35.1±4.6)%, (52.9±6.8)%, (56.2±3.1)%, and (71.2±9.6)% respectively, which were significantly lower than (106.3±12.3)% of normoxia control group (P<0.001). Survival rates of cells in hypoxia KGF group, hypoxia HIF-1α group, and hypoxia combine group were significantly higher than the rate of cells in hypoxia control group (P=0.023, 0.009, <0.001). Survival rate of cells in hypoxia combine group was significantly higher than the rates of cells in hypoxia KGF group and hypoxia HIF-1α group (P=0.017, 0.045). (3) After being cultured for 24 h, percentage of cells in G1 phase in hypoxia control group was significantly higher than that of cells in normoxia control group (P=0.030), percentages of cells in S phase in hypoxia control group, hypoxia KGF group, and hypoxia HIF-1α group were obviously lower than the percentage of cells in normoxia control group (P=0.020, 0.031, 0.026), and percentages of cells in different phases in other groups were close to those of cells in normoxia control group (P=0.516, 0.107, 0.052, 0.985, 0.637, 0.465, 0.314, 0.591). After being cultured for 24 h, percentages of cells in G1 phase in hypoxia control group, hypoxia KGF group, and hypoxia HIF-1α group were obviously higher than the percentage of cells in hypoxia combine group (P=0.001, 0.030, 0.014), and percentages of cells in S phase in the above 3 groups were obviously lower than the percentage of cells in hypoxia combine group (P=0.001, 0.012, 0.010). (4) After being cultured for 24 h, compared with that of cells in normoxia control group, apoptosis rate of cells in hypoxia control group obviously increased (P=0.018), and apoptosis rate of cells in hypoxia combine group obviously decreased (P=0.008). After being cultured for 24 h, compared with that of cells in hypoxia control group, apoptosis rates of cells in hypoxia KGF group and hypoxia combine group obviously decreased (P=0.004, 0.001). Apoptosis rate of cells in hypoxia combine group was obviously lower than those of cells in hypoxia KGF group and hypoxia HIF-1α group (P=0.032, 0.002). (5) After being cultured for 24 h, compared with that of cells in normoxia control group, the content of ATP of cells in hypoxia combine group changed unobviously (P=0.209), and content of ATP of cells in the other groups obviously decreased (P= <0.001, 0.001, 0.002). Content of ATP of cells in hypoxia HIF-1α group and hypoxia combine group was obviously higher than that of cells in hypoxia control group (P=0.044, 0.001). Content of ATP of cells in hypoxia combine group was obviously higher than that of cells in hypoxia KGF group and hypoxia HIF-1α group (P=0.011, 0.020). (6) After being cultured for 24 h, protein expressions of p53 of cells in hypoxia control group, hypoxia KGF group, and hypoxia HIF-1α group were obviously higher than that of cells in normoxia control group (P<0.001), and protein expression of p53 of cells in hypoxia combine group was obviously lower than those of cells in hypoxia control group, hypoxia KGF group, and hypoxia HIF-1α group (P=0.001, 0.001, 0.002). Conclusions: KGF combined with HIF-1α have significant protective effects on IEC-6 of rats with hypoxia stress, and can improve its survival in hypoxic environment by inhibiting cell cycle arrest, reducing the level of apoptosis, and increasing level of energy metabolism.

Active ingredients of Inula helenium L. exhibits similar anti-cancer effects as isoalantolactone in pancreatic cancer cells

Isoalantolactone is one of the major active ingredients from Inula helenium L. However, it is low cost-effective to isolate isoalantolactone from Inula helenium L. In this study, we optimized the extraction strategy and obtained a mixture of active ingredients with exact proportion (termed as F35), which were alloalantolactone, alantolactone and isoalantolactone at the ratio of 1/5/4 respectively. The anti-tumor activity of F35 was compared with isoalantolactone on pancreatic cancer cells. As a result, F35 showed nearly the same anti-proliferation activity as isoalantolactone in two cell lines. Both F35 and isoalantolactone could induce mitochondrion-related apoptosis at the concentration of 6 μg/ml. In addition, F35 inhibited colony-formation and migration of PANC-1 and SW1990 cells. To conclude, F35 exhibited similar anti-proliferation and anti-migration effect as isoalantolactone on two pancreatic cancer cell lines, suggesting that alantolactone or alloalantolactone might have comparable anti-tumor effect as isoalantolactone.

Comparing two classification schemes for seizures and epilepsy in rural China

BACKGROUND AND PURPOSE

The International League against Epilepsy (ILAE) updated the classifications of seizures and epilepsies in 2017. The 2017 classifications were compared with the 1980s classifications in rural China.

METHODS

People with epilepsy receiving treatment under the National Epilepsy Control Programme were recruited from rural areas in China. Their seizures and epileptic syndrome were classified using the 1980s ILAE classification system and then re-classified according to the 2017 system. Differences in seizure, epilepsy and aetiology classifications were identified.

RESULTS

A total of 597 individuals (58% males, aged 6-78 years) were included. Amongst them 535 (90%) had a single seizure type, 57 (9.55%) had two types and five (0.84%) had three. There was complete agreement between the 1981 and 2017 classifications for the 525 individuals with focal seizures. Seizures originally classified as generalized in 10 of 65 individuals were re-classified as unknown in the 2017 classification. Compared to the 1980s classifications, the proportion of individuals with unknown seizures and unknown epilepsy increased from 1.2% (7/597) to 2.8% (17/597, P = 0.002), and unknown aetiology increased from 32% (189/597: 182 cryptogenic and seven unclassified) to 39% (230/597; P < 0.001) in the 2017 classifications.

CONCLUSIONS

The 1980s and 2017 classifications had 100% agreement in classifying focal seizures and epilepsy in rural China. A small but significant proportion of generalized seizures and epilepsy and aetiologies classified in the old classifications were re-classified to unknown in the new classifications. These results highlight the need for improvement in clinical evaluation of people with epilepsy in resource-poor settings.

Distinct functions of CXCR3+ and CCR4+CD4+ T-cells accumulated in human tuberculosis pleural fluid

BACKGROUND

Chemokine receptors and their ligands play a prominent role in regulating leucocyte migration. In the local milieu of inflammation, a high concentration of chemokines can recruit different chemokine receptor-expressing lymphocytes.

OBJECTIVE

To understand the distinct immunological functions of CXC chemokine receptor 3 (CXCR3⁺) and CC chemokine receptor 4 (CCR4⁺) cluster of differentiation 4 (CD4⁺) T-cells accumulated in human tuberculosis (TB) pleural fluid after tuberculous antigen stimulation.

METHODS

Mononuclear cells were isolated from the peripheral blood of healthy donors, cord blood and TB pleural fluid, and expression of CXCR3 and CC chemokine receptor 4 (CCR4), cytokines and cytolytic molecules by CD4⁺ T-cells with or without stimulation were analysed using fluorescence-activated cell sorting.

RESULTS

CXCR3 and CCR4 expression on CD4⁺ T-cells from pleural fluid mononuclear cells (PFMCs) was significantly higher than in peripheral blood mononuclear cells (PBMCs). T-cell receptor signalling resulted in the upregulation of CXCR3 and CCR4 expression on CD4⁺ T-cells from cord blood mononuclear cells (CBMCs) and PBMCs in a time-dependent manner, but not from PFMCs. After stimulation with Mycobacterium tuberculosis antigens, CXCR3⁺CCR4^-CD4⁺ T-cells were dominated by multifunctional T-helper 1 cells; however, CXCR3⁺CCR4⁺CD4⁺ T-cells exhibited cytotoxicity and degranulation by expressing granzyme B, perforin, CD107a/b and tumour necrosis factor-related apoptosis-inducing ligand.

CONCLUSION

Our results indicated that CXCR3 or CCR4 expression on CD4⁺ T-cells had different biological activities against tuberculous infection, and could be a potential marker for the diagnosis of TB.

Apical U-shape splitting technique for undercut areas of the anterior alveolar ridge: a prospective non-randomized controlled study

The aim of this study was to investigate a novel apical U-shape splitting technique for horizontal bone augmentation in undercut areas and to compare its efficacy with that of guided bone regeneration (GBR). This was a prospective non-randomized controlled clinical trial. A total of 36 patients, who presented with a labial undercut that was not able to house a normally inclined implant, underwent the new technique or GBR. Radiographic and clinical data were obtained preoperatively, immediately after surgery, and 12 months after surgery. Pairwise comparisons of changes in ridge width gain, marginal bone loss, and pink aesthetic score were performed; correlations with pristine ridge morphology were investigated. The results showed similar marginal bone loss in the two groups. The overall ridge width gains in the new technique group (2.56±1.92mm) and GBR group (0.73±1.21mm) differed significantly (P<0.05). The pink aesthetic score was higher for the new technique group (11.75±1.22) than for the GBR group (9.25±1.86) (P<0.01). The morphology of the concavity had different impacts on regeneration in the two groups. The apical U-shape splitting technique, as a safe and effective alternative to GBR, provided a significant increase in bone volume gain where labial fenestration was inevitable during implant placement.

[Performance of matrix assisted laser desorption ionization time of flight biotyper system in clinical bacteria identification]

Objective: To evaluate the performance of MALDI Biotyper system in identification of clinically isolated pathogens so as to provide a new rapid identification method. Methods: Total 21 270 pathogens strains, isolated from the First Affiliated Hospital of Fujian Medical Universityduring Nov. 2015 to Dec. 2016, were identified by VITEK-Ⅱ, API and MALDI Biotyper system, respectively.The isolated strains were confirmed by DNA sequencing. Results: The identification of common bacteria with MALDI Biotyper and phenotypic system is highly consistent (>95% and >90%). Among 43 strains of anaerobic bacteria, MALDI Biotyper could identify 90.7% bacteria to species level and 97.7% bacteria to genus level with the statistical significance(χ(2)=6.76, P<0.01), while phenotypic system only identified 65.1% bacteria to species and 69.8% bacteria to genus. Also, no statistical significance was shown for Trichosporon and Candida(P>0.05). MALDI Biotyper could identify 76% filamentous fungi and all of Actinomycetes, Nocardia, Mycobacterium and Legionella to genus level. Conclusions: MALDI Biotyper is an easy-performed, sensitive method for the identification of clinically isolated pathogens. Additionally, the pretreatment and reference database has the effect on identification.

Clinicopathologic charcterization of sorafenib-induced endoplasmic reticulum stress in human liver cancer cells

Sorafenib (Sor) is clinical standard therapy for advanced hepatocellular carcinoma (HCC). However, detailed molecular mechanism behind Sor-exerted pharmacological effect remains unknown. In this study, sera samples, staged hepatic cancer tissues from Sor-treated patients with advanced HCC were harvested for a group of biochemical tests and immunoassays. Compared to non-treated control, blood contents of alanine transaminase (ALT), aspartate transaminase (AST), alphafetoprotein (AFP), fibroblast growth factor 21 (FGF21) were decreased in Sor-treated HCC patients, while the level of interleukin 10 (IL-10) were increased. As well, reduced triglyceride (TG), total cholesterol (T-CHOL), interferon gamma (IFN-γ), and tumor necrosis factor alpha (TNF-α) levels in sera were checked in Sor-treated HCC patients. In comparison with non-treated cancer sections, Sor-treated HCC cells showed decreased positive cells of proliferative marker for proliferating cell nuclear antigen (PCNA) and metastasized biomarker for cytokeratin 19 (CK19). In addition, elevated immunofluorescence-labeled cells of endoplasmic reticulum (ER)-stress markers of activating transcription factor 6 (ATF6), eukaryotic initiation factor 2α kinase (eIF2α), glucose-regulated protein (GRP-78), X-box binding protein 1 (XBP1) were observed in Sor-treated HCC livers. Further, validated data from Western blot assay exhibited that hepatocellular expressions of ATF6, eIF2α, GRP78, XBP1 in Sor-treated HCC liver cells were up-regulated. Briefly, our present clinicopathologic findings indicate that Sor-induced ER stress may be responsible for therapeutic mechanism against advanced HCC. In addition, induction of intracellular ER stress functions as a promising strategy for treating advanced HCC.

[Analysis on voluntary blood donation and associated factors in men who have sex with men in 3 cities in China]

Objective: To assess the prevalence of blood donation and associated factors in men who have sex with men (MSM) in China. Methods: Our observational study was conducted between January and August, 2017 in 3 cities: Guangzhou, Shenzhen and Wuxi. Eligible participants were MSM (≥18 years old) who had either ≥2 male sex partners or unprotected anal sex with casual partners, or had been diagnosed with STI in the past 6 months. A self-completed tablet-based questionnaire was used to collect the information about MSM's socio-demographic characteristics, sexual behaviors and blood donation history. Results: A total of 603 MSM were enrolled in our study, including 302 in Guangzhou, 152 in Shenzhen and 149 in Wuxi, with a mean age of 27.9 years (SD=7.8). Overall, 29.2% (176/603) of the MSM reported a history of blood donation, and 33.1% (100/302)in Guangzhou, 27.6% (42/152) in Shenzhen and 22.8% (34/149) in Wuxi, the differences were not significant (χ(2)=6.421, P=0.093). Multivariate logistic regression analysis indicated that MSM had ever tested for HIV for ≥2 times in the past 12 months (vs. MSM tested for HIV one time, aOR=1.49, 95%CI: 1.08-2.19) or who had ever used gay dating app (vs. MSM who not used gay dating app, aOR=2.13, 95%CI: 1.12-4.44) were more likely to donate blood. Conclusions: Blood donation was common in MSM in China. Health education about blood donation in MSM should be strengthened to ensure the blood safety.

Evaluation of the readout electronics based on the center of gravity method for position sensitive radiation detection

In the application of position sensitive radiation detection, the center of gravity method is often used to obtain better spatial resolution. In order to obtain the resolution degradation caused by the readout electronics, an evaluation method is put forward in this paper. The principle of the method is to simulate the signal distribution on sense wires of the MWPC (Multiwire Proportional Chamber) detector. The evaluation software quantizes the simulated data and drives the digital to analog converter to generate test signals. The readout electronics is evaluated with these stimulus signals according to the readout scale. An evaluation board based on this method is implemented. Tests are carried out in the laboratory to evaluate a readout circuit for the MWPC detector. The position resolution contributed by the electronics is better than 15 μm when the swtiching frenquency of the switch array is 12.5 MHz. The test results proved that the evaluation method is correct and practical. It can greatly simplify the evaluation of the readout electronics.

Note: Calibration of majority isotopes for enriched and depleted uranium fission chambers by using the elimination method with fast neutrons

Calibrated miniature pulse fission chambers (MPFCs) can be used for absolute measurement of the fission reaction rate in neutronic experiments. Absolute measurements require the effective number of fissionable atoms (ENFAs) in the coating of the chambers. An elimination method was proposed to calibrate the MPFCs embodying highly enriched and depleted uranium, using 14.75 MeV fast neutrons from the D-T reaction. The ENFAs of ²³⁵U in enriched uranium MPFC and ²³⁸U in depleted uranium MPFC are 8.39 × 10¹⁸ and 9.55 × 10¹⁸, with the uncertainties of 5.27% and 4.76%, respectively.

Polybrominated Diphenyl Ethers Quinone Induced Parthanatos-like Cell Death through a Reactive Oxygen Species-Associated Poly(ADP-ribose) Polymerase 1 Signaling

Polybrominated diphenyl ethers (PBDEs) are emerging organic environmental pollutants, which were accused of various toxic effects. Here, we studied the role of a potential PBDEs quinone metabolite, PBDEQ, on cytotoxicity, oxidative DNA damage, and the alterations of signal cascade in HeLa cells. PBDEQ exposure leads to reactive oxygen species (ROS) accumulation, mitochondrial membrane potential (MMP) loss, lactate dehydrogenase (LDH) release, increasing terminal transferase-mediated dUTP-biotin nick end labeling (TUNEL) positive foci, and the elevation of apoptosis rate. Furthermore, we showed PBDEQ exposure result in increased DNA migration, micronucleus frequency, and the promotion of 8-OHdG and phosphorylation of histone H2AX (γ-H2AX) levels. Mechanism study indicated that PBDEQ caused poly(ADP-ribose) polymerase 1 (PARP-1) activation and apoptosis-inducing factor (AIF) nuclear translocation. All together, these results confirmed the occurrence of parthanatos-like cell death upon PBDEQ exposure.

Investigation of the predisposing factor of pemphigus and its clinical subtype through a genome-wide association and next generation sequence analysis

BACKGROUND

Pemphigus is an autoimmune blistering disease with pemphigus vulgaris (PV) and foliaceus (PF) as the two major histological subtypes. Associations with HLA molecules have been suggested, but specific HLA risk variants as well as non-HLA risk variants remain to be discovered.

METHODS

We performed a two-stage genome-wide association study in the Chinese Han population through a genome-wide discovery analysis and follow-up validation analysis in a total number of 210 PV, 159 PF and 2493 healthy controls. HLA imputation as well as high coverage next generation sequencing based HLA genotyping was employed to investigate the association of classical HLA alleles and amino acid change.

RESULTS

We have discovered independent novel associations with PF at rs2178077 on 12q24.33, located next to RAN (P_PF = 1.57 × 10^-9 ) and rs3888722 within the MHC region (P = 6.73 × 10^-9 ). For the HLA variants, we confirmed independent genome-wide level risk associations in HLA-DQB1 and HLA-DRB1, with DQB1*05:03 to be the strongest association with PV (P = 8.59 × 10^-68 , OR = 31.16) and PF (P = 4.84 × 10^-17 , OR = 5.64). In addition, DRB1*14 was demonstrated to be a second independent variants (P = 4.2 × 10^-63 , OR = 35.47) for PV, while DRB1*04:06 was demonstrated to be the second independent signal (P = 7.44 × 10^-13 , OR = 5.58) for PF.

CONCLUSIONS

These findings advance our understanding of the genetic basis of pemphigus susceptibility and may offer opportunities for risk prediction and preventive treatment for pemphigus, in particular for PV.

Primary Angioplasty without Stenting for Symptomatic, High-Grade Intracranial Stenosis with Poor Circulation

BACKGROUND AND PURPOSE

Although the Stenting versus Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) study demonstrated a high incidence of perioperative complications for Intracranial Atherosclerotic disease (ICAD) treatments with stent placement, some studies have shown that submaximal angioplasty with an undersized balloon limits the risks of perioperative complications, suggesting that intervention may remain an alternative option for ICAD if perioperative complications are minimized. We sought to evaluate clinical and angiographic outcomes after primary angioplasty without stent placement in patients with symptomatic, high-grade intracranial stenosis and poor antegrade flow who were refractory to medical therapy.

MATERIALS AND METHODS

All cases with high-grade, symptomatic intracranial stenosis and poor antegrade flow treated with intracranial angioplasty without stent placement at Xuanwu Hospital, Capital Medical University, from January 2010 to December 2016, were retrospectively reviewed. The main outcomes included the changes in antegrade flow and residual stenosis and any stroke or death within 1 month. We also evaluated functional outcomes, stroke, and restenosis in patients on follow-up.

RESULTS

Thirty-five patients (mean age, 64.3 years) were included, and the mean follow-up time was 9.7 months. The average preprocedural stenosis was 88.4%. The immediate, average postprocedure stenosis rate was 25.3%, and the average postprocedural stenosis rate at last angiographic follow-up was 34.7%. The primary end point of major stroke or death at 30 days was observed in 1 patient (1/35, 2.9%), and no patient had intraprocedural complications. The incidence of stroke or death at the last follow-up was 2.9%, which was superior to the results of the medical and stent-placement arms of the SAMMPRIS study. Severe restenosis was observed in 3 (3/25, 12%) patients but without any symptoms.

CONCLUSIONS

In this retrospective series, primary balloon angioplasty was an effective treatment option for symptomatic intracranial stenosis with a high risk of stroke.

[Clinical characteristics of 13 neuroendocrine prostate cancer patients]

Objective: To explore the radiological, pathological features and clinical characteristics of neuroendocrine prostate cancer patients(NEPC). Methods: The clinical characteristics and pathology data of 13 neuroendocrine prostate cancer patients treated in the Affiliated Hospital of Tianjin Medical University from January 2004 to January 2015 were analyzed retrospectively. Results: Of all 13 patients, three cases were primally diagnosed small cell cancer, and 10 cases were translated to neuroendocrine type from adenocarcinoma after endocrine therapy. Frequent urination, urgency, nocturia, and dysuria were main symptoms. Serum prostate-specific antigen (PSA) was (14.5±3.2)μg/L; the volume of prostate was enlarged, mean volume, range 28-176(45±4)ml. The lesion was moderately low signal intensity in T(2)WI, while slightly higher signal in DWI. Signal characteristic of dynamic enhanced MRI was "fast in fast out" . The expression of Synaptophysin, Chromogranin A , CD56 and Ki-67 in NEPC were highly expressed by immunohistochemistry analysis. Among them, five patients accepted intravenous chemotherapy, two cases received external radiation therapy, three cases received cryoablation and three cases received palliative therapy. Median survival time in all 13 patients was 10 months, while median survival time in patients treated by chemotherapy was 16 months . Conclusion: NEPC is a highly aggressive subtype of prostate cancer characterized by rapid disease progression, lack of treatment and worse prognosis. Therefore, patients with NEPC may benefit from early diagnosis and comprehensive treatment with chemotherapy.

Research on correlation between GALNT3 gene and osteoporosis

OBJECTIVE

The aim of this study was to explore the correlation between GALNT3 gene and osteoporosis.

PATIENTS AND METHODS

In this study, 184 cases of osteoporosis that were treated at our hospital from 2013 to 2014 were selected as research subjects in the observation group. In addition, 84 healthy people were selected as the control group from 2013 to 2014. The bone mineral density of the observation and control groups were detected by x-rays and the expression levels and differences of mRNA of the GALNT3 gene and protein in their body was detected using fluorescence quantitative polymerase chain reaction (qPCR), enzyme-linked immunoassay, and Western blotting.

RESULTS

X-ray results suggest that when compared to the healthy group, bone mineral density of patients in the observation group was significantly lower than that of research subjects in the control group, with significant differences. The fluorescence qPCR results suggest that the expression levels of mRNA of the GALNT3 gene in patients with osteoporosis were significantly lower than that in the healthy group (p<0.05). Enzyme-linked immunosorbent assay (ELISA) results suggest that the expression levels of the GALNT3 gene in patients with osteoporosis (1.26±0.32) μg/L was significantly lower than that in the healthy group (12.41±0.28) μg/L, with significant differences (p<0.05). The Western blotting results agreed with the ELISA results. We also found in our research that the bone mineral density of patients with osteoporosis significantly correlated with the expression levels of the GALNT3 gene (r=0.95).

CONCLUSIONS

Therefore, the GALNT3 gene significantly correlated with osteoporosis and the low expression of GALNT3 gene can promote the occurrence and deterioration of osteoporosis.

[The influence of chemotherapy-induced leucopenia on the disease-free survival of gastric cancer patients after radical gastrectomy]

Objective: To investigate the association between chemotherapy-induced leucopenia and patients' disease-free survival in gastric cancer patients who received radical gastrectomy. Methods: The clinical data of 273 gastric cancer patients who received radical gastrectomy and postoperative adjuvant chemotherapy between January, 2010 and December, 2015 in PLA 309(th) hospital was reviewed retrospectively. Results: A total of 195 (71.4%) patients experienced at least one time of leucopenia, while it was absent in the other 78 (28.6%) patients. The median disease-free survival of patients with or without leucopenia was 49.7 and 44.0 months respectively (P=0.009), leucopenia was an independent factor influencing patients' disease-free survival (HR=2.758, P=0.022), but there was no statistical difference between the disease-free survival of patients with different degrees and frequency of leucopenia (P=0.446, 0.123). Conclusion: Chemotherapy-induced leucopenia is a predictor of good prognosis for gastric cancer patients who receive radical gastrectomy.

Ambipolar ferromagnetism by electrostatic doping of a manganite

Complex-oxide materials exhibit physical properties that involve the interplay of charge and spin degrees of freedom. However, an ambipolar oxide that is able to exhibit both electron-doped and hole-doped ferromagnetism in the same material has proved elusive. Here we report ambipolar ferromagnetism in LaMnO₃, with electron-hole asymmetry of the ferromagnetic order. Starting from an undoped atomically thin LaMnO₃ film, we electrostatically dope the material with electrons or holes according to the polarity of a voltage applied across an ionic liquid gate. Magnetotransport characterization reveals that an increase of either electron-doping or hole-doping induced ferromagnetic order in this antiferromagnetic compound, and leads to an insulator-to-metal transition with colossal magnetoresistance showing electron-hole asymmetry. These findings are supported by density functional theory calculations, showing that strengthening of the inter-plane ferromagnetic exchange interaction is the origin of the ambipolar ferromagnetism. The result raises the prospect of exploiting ambipolar magnetic functionality in strongly correlated electron systems.

Influence of Waveform Characteristics on LiDAR Ranging Accuracy and Precision

Time of flight (TOF) based light detection and ranging (LiDAR) is a technology for calculating distance between start/stop signals of time of flight. In lab-built LiDAR, two ranging systems for measuring flying time between start/stop signals include time-to-digital converter (TDC) that counts time between trigger signals and analog-to-digital converter (ADC) that processes the sampled start/stop pulses waveform for time estimation. We study the influence of waveform characteristics on range accuracy and precision of two kinds of ranging system. Comparing waveform based ranging (WR) with analog discrete return system based ranging (AR), a peak detection method (WR-PK) shows the best ranging performance because of less execution time, high ranging accuracy, and stable precision. Based on a novel statistic mathematical method maximal information coefficient (MIC), WR-PK precision has a high linear relationship with the received pulse width standard deviation. Thus keeping the received pulse width of measuring a constant distance as stable as possible can improve ranging precision.

Editorial: Prevention of Alzheimer's Disease in Chinese Populations: Status, Challenges and Directions

n January 2018, the investigators from Eli Lily’s EXPEDITION3 trial published their negative findings of a large phase 3 trial on the antibody Solanezumab (1). The lacking of statistically significant between-group difference on primary endpoint dampened enthusiasm again, and added the study to a long and growing list of failed trials (including EXPEDITION 1 and EXPEDITION2 from the same company) in the field of AD therapeutics. Without promising disease modifying agents, more and more clinicians and scientists in the field start to believe that prevention is better (and maybe easier) than treatment. In the West, scientists, lobbyists and advocacy groups are working hard in persuading the governments and funding agencies to invest more on efforts related to primary prevention of AD. A major study, the US POINTER will soon be initiated in 2018 in the U.S.

A novel flow sensor based on resonant sensing with two-stage microleverage mechanism

The design, simulation, fabrication, and experiments of a novel flow sensor based on resonant sensing with a two-stage microleverage mechanism are presented in this paper. Different from the conventional detection methods for flow sensors, two differential resonators are adopted to implement air flow rate transformation through two-stage leverage magnification. The proposed flow sensor has a high sensitivity since the adopted two-stage microleverage mechanism possesses a higher amplification factor than a single-stage microleverage mechanism. The modal distribution and geometric dimension of the two-stage leverage mechanism and hair are analyzed and optimized by Ansys simulation. A digital closed-loop driving technique with a phase frequency detector-based coordinate rotation digital computer algorithm is implemented for the detection and locking of resonance frequency. The sensor fabricated by the standard deep dry silicon on a glass process has a device dimension of 5100 μm (length) × 5100 μm (width) × 100 μm (height) with a hair diameter of 1000 μm. The preliminary experimental results demonstrate that the maximal mechanical sensitivity of the flow sensor is approximately 7.41 Hz/(m/s)² at a resonant frequency of 22 kHz for the hair height of 9 mm and increases by 2.42 times as hair height extends from 3 mm to 9 mm. Simultaneously, a detection-limit of 3.23 mm/s air flow amplitude at 60 Hz is confirmed. The proposed flow sensor has great application prospects in the micro-autonomous system and technology, self-stabilizing micro-air vehicles, and environmental monitoring.

[Spatial and temporal clustering characteristics of typhoid and paratyphoid fever and its change pattern in 3 provinces in southwestern China, 2001-2012]

Objective: To analyze the spatial and temporal clustering characteristics of typhoid and paratyphoid fever and its change pattern in Yunnan, Guizhou and Guangxi provinces in southwestern China in recent years. Methods: The incidence data of typhoid and paratyphoid fever cases at county level in 3 provinces during 2001-2012 were collected from China Information System for Diseases Control and Prevention and analyzed by the methods of descriptive epidemiology and geographic informatics. And the map showing the spatial and temporal clustering characters of typhoid and paratyphoid fever cases in three provinces was drawn. SaTScan statistics was used to identify the typhoid and paratyphoid fever clustering areas of three provinces in each year from 2001 to 2012. Results: During the study period, the reported cases of typhoid and paratyphoid fever declined with year. The reported incidence decreased from 30.15 per 100 000 in 2001 to 10.83 per 100 000 in 2006(annual incidence 21.12 per 100 000); while during 2007-2012, the incidence became stable, ranging from 4.75 per 100 000 to 6.83 per 100 000 (annual incidence 5.73 per 100 000). The seasonal variation of the incidence was consistent in three provinces, with majority of cases occurred in summer and autumn. The spatial and temporal clustering of typhoid and paratyphoid fever was demonstrated by the incidence map. Most high-incidence counties were located in a zonal area extending from Yuxi of Yunnan to Guiyang of Guizhou, but were concentrated in Guilin in Guangxi. Temporal and spatial scan statistics identified the positional shifting of class Ⅰ clustering area from Guizhou to Yunnan. Class Ⅰ clustering area was located around the central and western areas (Zunyi and Anshun) of Guizhou during 2001-2003, and moved to the central area of Yunnan during 2004-2012. Conclusion: Spatial and temporal clustering of typhoid and paratyphoid fever existed in the endemic areas of southwestern China, and the clustering area covered a zone connecting the central areas of Guizhou and Yunnan. From 2004 to 2012, the most important clustering area shifted from Guizhou to Yunnan. Findings from this study provided evidence for the identifying key areas for typhoid and paratyphoid fever control and prevention and allocate health resources.

Interleukin-17A participates in podocyte injury by inducing IL-1β secretion through ROS-NLRP3 inflammasome-caspase-1 pathway

Studies show that the Th17/IL-17A axis plays an important role in the pathogenesis of kidney diseases. Previously, we also showed that IL-17A may play a role in the pathogenesis of primary nephrotic syndrome; however, the underlying mechanism(s) is unclear. The aim of this study was to explore the molecular mechanism of IL-17A-inducing podocyte injury in vitro. In this study, the NLRP3 inflammasome activation and the morphology of podocytes were detected by Western blot and immunofluorescence. The results showed that podocytes persistently expressed IL-17A receptor and that NLRP3 inflammasome in these cells was activated upon exposure to IL-17A. Also, activity of caspase-1 and secretion of IL-1β increased in the presence of IL-17A. In addition, IL-17A disrupted podocyte morphology by decreasing expression of podocin and increasing expression of desmin. Blockade of intracellular ROS or inhibition of caspase-1 prevented activation of the NLRP3 inflammasome, thereby restoring podocyte morphology. Taken together, the results suggest that IL-17A induces podocyte injury by activating the NLRP3 inflammasome and IL-1β secretion and contributes to disruption of the kidney's filtration system.

Scanty smears associated with initial loss to follow-up in South African tuberculosis patients

BACKGROUND

Smear-positive patients should be started on anti-tuberculosis treatment promptly. However, studies show that up to 38% of diagnosed patients are initial loss to follow-up (LTFU), meaning they do not start treatment after diagnosis. We investigated determinants of initial LTFU at primary health care facilities.

DESIGN

In a facility-matched case-control study, health care facilities were visited from October 2010 to September 2012. After identification from registers, patients were traced and invited to complete a questionnaire.

RESULTS

Of 973 participants, 233 (24%) were cases and 740 (74%) controls. Initial LTFU was associated with smear grade (pooled adjusted odds ratio [aOR] 0.73, 95% confidence interval [CI] 0.64-0.90, scanty at baseline) for participants identified at facilities, but not with age (overall P = 0.80) or sex (aOR 0.83, 95%CI 0.58-1.20). Of the 233 cases, 197 (85%) were traced in the community, of whom 58 (29%) were found. Among the group found, initial LTFU was associated with age (aOR 3.38, 95%CI 1.15-9.95) and smear grade (aOR 0.08, 95%CI 0.02-0.34, scanty at baseline).

CONCLUSION

Scanty smear positivity was associated with initial LTFU. Tuberculosis programmes should start scanty smear-positive patients on treatment early and develop alternative community tracing strategies. Health care worker training could address the first aspect, and the use of technology to improve treatment initiation, such as mobile phone applications, the second.

Abstract P3-01-06: Can axillary evaluation be omitted in patients preoperatively diagnosed with ductal carcinoma in situ by core needle biopsy?

Background

Patients diagnosed with ductal carcinoma in situ (DCIS) by core needle biopsy (CNB) have a great chance of upgrading invasive cancer on the final pathology. Positive axillary lymph nodes can be found in these patients. The present study sought to identify clinicopathological factors associated with upgrading and axillary lymph nodes metastasis in patients preoperatively diagnosed with DCIS by CNB.

Materials and Methods

This study identified 604 patients (cT1-3N0M0) with preoperative diagnosis of pure DCIS by CNB who had undergone axillary evaluation from August 2006 to December 2015 at Fudan University Shanghai Cancer Center (FUSCC). Predictors of upgrading and axillary lymph nodes metastasis were analyzed, respectively.

Results

Of all 604 patients, 513 (84.93%) and 91 (15.07%) patients had undergone sentinel lymph nodes biopsy (SLNB) and axillary lymph nodes dissection (ALND), respectively. Overall, 121 (20.03%) and 193 (31.95%) patients were upgraded to DCIS with microinvasion (DCISM) and IDC on final pathology, respectively. Positive axillary lymph nodes were identified in 41 (6.79%) patients, of which 35 (5.80%) patients had 1-2 positive axillary lymph nodes, 6 (0.99%) patients had 3 or more positive axillary lymph nodes. Among patients with axillary lymph nodes metastasis, 4 (9.76%), 4 (9.76%) and 33 (80.48%) patients were in DCIS, DCISM and IDC group, respectively. Predictors of upgrading included tumor size on ultrasonography (P=0.001), Ki-67 (P=0.046) and molecular subtype (P=0.007) in univariate analysis. In multivariate analysis, patients with larger tumor size on ultrasonography (&gt;2cm) (OR 1.767, P=0.001) were more likely to be upgraded on final pathology. Also, ER+ HER2+ patients were more likely to be upgraded than ER+ HER2- patients (OR 1.659, P=0.047). Factors associated with axillary lymph nodes metastasis included nipple discharge (P&lt;0.001), tumor size on pathology (P=0.037), number of lesions (P=0.039), axillary evaluation methods (P=0.029) and molecular subtype (P=0.049) in univariate analysis. Whereas, only nipple discharge and larger tumor size on pathology (&gt;2cm) reached statistical significance in multivariate analysis (OR 5.959, P&lt;0.001; OR 2.361, P=0.042). In addition, further analysis showed upgrading on final pathology had a significant influence on axillary lymph nodes status (P&lt;0.001). However, this correlation was not shown between patients with DCIS and DCISM in pairwise comparison.

Conclusion

The data of upgrading and axillary lymph nodes metastasis in patients with an initial diagnosis of DCIS by CNB was comparable in this cohort with published data. Despite of a 51.98% upgrading rate, the rate of axillary lymph nodes metastasis in these patients is low, which supports the omission of axillary evaluation in selected patients.

Citation Format: Si J, Yang B, Guo R, Huang N, Quan C, Chen J, Wu J. Can axillary evaluation be omitted in patients preoperatively diagnosed with ductal carcinoma in situ by core needle biopsy? [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-01-06.

Methylmercury-l-Cysteine targeting L-type amino acid transporter conjugate cytotoxicity on C6 glioma cells

Glioma is the most common primary tumor in the brain, accounting for about 40~50% of intracranial primary tumors. Most chemotherapeutic drugs have difficulty in penetrating the blood-brain barrier, and their clinical applications are greatly limited. We evaluated the effects of methylmercury-L-cysteine (MeHg-L-cys) and methylmercury chloride (MMC) on apoptosis of C6 glioma cells. L-type amino acid transporter (LAT1) was used to investigate the targeted transport function and cytotoxicity of MeHg- L-cys in glioma. MeHg-L-cys enhanced the ability of targeting glioma cells and reduced the adverse reactions to normal brain tissues. Therefore, it is significantly important to develop new anti-glioma drugs targeting the blood-brain barrier.

IL-23 Activated γδ T Cells Affect Th17 Cells and Regulatory T Cells by Secreting IL-21 in Children with Primary Nephrotic Syndrome

This study (1) analysed the percentage of γδ T cells, γδ T cell subsets, Th17 cells and regulatory T cells (Treg cells) and (2) determined the role of IL-23 in primary nephrotic syndrome (PNS) patients with active disease and in remission. Eighty-four patients with PNS and 51 healthy age-matched controls were included in this study. The percentage of γδ T cells, γδ T cell subsets, Th17 cells and Treg cells in peripheral blood mononuclear cells (PBMCs) were analysed by fluorescence-activated cell sorting. PMBCs from PNS patients with active disease were cultured in the presence of IL-23, IL-23 and an IL-23 antagonist, or IL23 and an anti-IL-21 monoclonal antibody (mAb). The percentage of γδ T cells, IL-23R⁺ γδ T cells and IL-17⁺ γδ T cells were significantly increased in PNS patients with active disease. There was a positive correlation between the percentage of γδ T cells, IL-23R⁺ γδ T cells, IL-17⁺ γδ T cells and the Th17/Treg ratio. IL-23 increased the percentage of γδ T cells and Th17 cells and decreased the percentage of Treg cells in PBMCs isolated from PNS patients with active disease. Anti-IL-21 mAb reduced the percentage of γδ T cells and Th17 cells, but increased the percentage of Treg cells. γδ T cells, IL-17⁺ γδ T cells and IL-23R⁺ γδ T cells may be involved in the pathogenesis of paediatric PNS by modulating the balance of Th17/Treg cells. γδ T cells may cause an imbalance in Th17/Treg cells by secreting IL-21 in the presence of IL-23.

SLC14A1: a novel target for human urothelial cancer

Urinary bladder cancer is the second commonly diagnosed genitourinary malignancy. Previously, bio-molecular alterations have been observed within certain locations such as chromosome 9, retinoblastoma gene and fibroblast growth factor receptor-3. Solute carrier family 14 member 1 (SLC14A1) gene encodes the type-B urea transporter (UT-B) which facilitates the passive movement of urea across cell membrane, and has recently been related with human malignancies, especially for bladder cancer. Herein, we discussed the SLC14A1 gene and UT-B protein properties, aiming to elucidate the expression behavior of SLC14A1 in human bladder cancer. Furthermore, by reviewing some well-established theories regarding the carcinogenesis of bladder cancer, including several genome wide association researches, we have bridged the mechanisms of cancer development with the aberrant expression of SLC14A1. In conclusion, the altered expression of SLC14A1 gene in human urothelial cancer may implicate its significance as a novel target for research.

5-Lipoxygenase Knockout Aggravated Apical Periodontitis in a Murine Model

5-Lipoxygenase (5-LO) plays a vital role in the host innate immune response, including bacteria-induced inflammation. Apical periodontitis (AP) is due to immune disorders caused by imbalances between bacterial invasion and subsequent host defense response. In this work, we investigated the role of 5-lipoxygenase in AP by using 5- lo knockout mice (5- lo-/- mice). Results showed that 5- lo-/- mice had greater periapical bone loss and more osteoclasts positive for tartrate-resistant acid phosphatase staining than did wild-type mice, as determined by micro-computed tomography and histologic staining. The inflammation- and osteoclastogenesis-related factors IL-1β, TNF-α, RANK, and RANKL were also significantly elevated in 5- lo-/- mice, whereas osteoprotegerin was reduced. Furthermore, peritoneal macrophages from 5- lo-/- mice revealed an obviously impaired ability to phagocytose the AP pathogenic bacteria Fusobacterium nucleatum. In vivo experiments confirmed that 5- lo knockout led to decreased macrophage recruitment and increased F. nucleatum infection around the periapical area due to decreased leukotriene B₄ and LXA4 production. All these results showed that 5- lo knockout impaired the host innate immune system to promote the release of bone resorption-related factors. Therefore, 5- lo deficiency aggravated AP in an experimental murine AP model.