[Senolytic effects on dental pulp stem cell's proliferation and differentiation during long-term expansion]

Objective: To investigate the impact of intermittent senescent cell clearance on the proliferation and differentiation of dental pulp stem cells (DPSC) in long-term, large-scale expansion, and to explore strategies for maintaining the youthful state of DPSC in vitro. Methods: Human-derived dental pulp stem cells were isolated from healthy permanent teeth extracted for orthodontic or impeding eruption reasons, provided by the Department of Oral and Maxillofacial Surgery at West China Hospital of Stomatology, Sichuan University. Long-term, large-scale in vitro expansion of DPSC was conducted. The study compared young DPSC (passage 5) with aged DPSC (passage 25) using cellular senescence-associated β-galactosidase staining, colony formation assay, and Alizarin Red S staining for osteogenic differentiation induction. To assess the differences between the two cell populations in terms of senescence and amplification and differentiation ability. Medicine screening for the most effective senolytic was compared among 5 common senolytics [Navitoclax (ABT-263), curcumin, dasatinib, fisetin, and quercetin]. The clearance efficacy was compared using cellular senescence-associated β-galactosidase staining to reflect the changes in senescent cell ratio. The senolytic with the highest efficacy was chosen for further experiments. The passage at which the proportion of senescent cells significantly increased was identified, and the selected senolytic was administered three times at three-generation intervals from that passage to remove senescent cells. Both the control and senolytic-treated groups were estimated by fluorescence cellular senescence-associated β-galactosidase staining, real-time flurogenic quantitative PCR (qPCR), colony formation assay, wound healing assay, and Alizarin Red S staining for osteogenic differentiation induction. Subcutaneous heterotopic osteogenesis was performed in nude mice and the grafts were analyzed by HE staining and alkaline phosphatase (ALP) immunohistochemical staining. Results: The proportion of senescent cells increased as the expansion extended, leading to decreased proliferation and osteogenic differentiation ability of senescent DPSC compared to young DPSC (P<0.05). Senescent DPSC exhibited altered mRNA expression levels of senescence-related genes, including p21, p16INK4a, IL-6, and Ki67 (P<0.001). Among the five senolytics, ABT-263 demonstrated higher clearance efficiency (P<0.05). After intermittent ABT-263 treatment during expansion, the proportion of senescent cells in the senolytic-treated group [(6.72±2.34)%] was significantly lower than that in the control group [(31.82±0.57)%] (P<0.001). qPCR confirmed that compared with the control group, mRNA expressions of p21, p16INK4a, and IL-6 in the senolytic-treated group were significantly decreased (P<0.05), while mRNA expressions of Ki67 were significantly increased (P<0.01). Furthermore, the cell healing ability and osteogenic differentiation ability of the senolytic-treated group were higher than those of the control group (P<0.05). In vivo experimental results indicated that the relative new bone area [(2.36±0.48)%] after DPSC transplantation in the senolytic-treated group was greater than that in the control group [(1.00±0.46)%] (P<0.05), and the expression of ALP was higher than that in the control group (P<0.01). Conclusions: ABT-263 can effectively eliminate senescent cells in long-term large-scale DPSC expansion. Continuous: treatment with ABT-263 during cultivation can maintain the proliferation and differentiation ability of DPSC both in vivo and in vitro.

Pretreatment synthetic MRI features for triple-negative breast cancer

AIM

To evaluate the quantitative parameters derived from synthetic magnetic resonance imaging (SyMRI) for predicting triple-negative breast cancer (TNBC).

MATERIALS AND METHODS

This prospective study enrolled participants with invasive ductal breast carcinoma (IDBC) and separated them into a TNBC group and a Non-TNBC group. Preoperative breast MRI included both the SyMRI and conventional MRI sequences. The quantitative parameters derived from the SyMRI included T1 and T2 relaxation times, proton density (PD), and their standard deviations (SD). Clinicopathological characteristics, conventional MRI findings, and quantitative synthetic parameters were assessed for all participants. Multivariable logistic regression analysis was performed to determine the potential independent imaging predictors for TNBC preoperatively. Receiver operating characteristic (ROC) curve analysis was used to evaluate the performance of these parameters.

RESULTS

A total of 231 participants with histopathological proven IDBC were included in this study (n=46 in the TNBC group and n=185 in the Non-TNBC group). The TNBC group had significantly larger tumour size (p=0.011) and more frequent intratumoural cystic or necrotic lesions (p<0.001) as compared to the Non-TNBC group. The univariate analysis showed that the TNBC tumours had significantly higher T1 (p=0.006) and T2 (p<0.001) values than Non-TNBC tumours. Subsequent multivariable analysis indicated that T2 values and the presence of cystic or necrotic lesions were the independent predictors for TNBC.

CONCLUSION

The T2 from synthetic imaging and the presence of cystic degeneration or necrosis within the breast cancer may serve as potential imaging biomarkers for preoperative differentiation of TNBC from Non-TNBC.

Genes associated with N6-methyladenosine regulators provide insight into the prognosis and immune response to renal clear cell carcinoma

As one of the most common messenger ribonucleic acid modifications in eukaryotic organisms, N6-methyladenosine (m6A) is involved in a wide variety of biological functions. The imbalance of m6A RNA modification may be linked to cancer and other disorders, according to a growing body of studies. Its effects on clear cell renal cell carcinoma (KIRC) have not been well discussed, though. Here, we acquired the expression patterns of 23 important regulators of m6A RNA modification and assess how they might fare in KIRC. We observed that 17 major m6A RNA modification regulatory factors had a substantial predictive influence on KIRC. Using the "ConsensusCluster" program, we defined two groupings (Cluster 1 and Cluster 2) depending on the expression of the aforementioned 17 key m6A RNA methylation regulators. The Cluster 2 has a less favorable outcome and is strongly related with a lesser immune microenvironment, according to the findings. We also developed a strong risk profile for three m6A RNA modifiers (METTL14, YTHDF1, and LRPPRC) using multivariate Cox regression analysis. According to further research, the aforementioned risk profile could serve as an independent predicting factor for KIRC, and the chemotherapy response sensitivity was analyzed between two risk groups. Moreover, to effectively forecast the future outlook of KIRC clients, we established a novel prognostic approach according to gender, age, histopathological level, clinical stage, and risk score. Finally, the function of hub gene METTL14 was validated by cell proliferation and subcutaneous graft tumor in mice. In conclusion, we discovered that m6A RNA modifiers play an important role in controlling KIRC and created a viable risk profile as a marker of prediction for KIRC clients.

TNFSF14 mediates the impact of docosahexaenoic acid on atopic dermatitis: a Mendelian randomization study

OBJECTIVE

While current research suggests potential value for docosahexaenoic acid (DHA) in the prevention and management of atopic dermatitis (AD), the causal relationship between DHA and AD remains unclear, and the underlying mechanisms are not well understood.

MATERIALS AND METHODS

To investigate the potential causal relationship between DHA and AD, as well as to explore potential mediating mechanisms, we employed the Mendelian randomization (MR) methods. To study these potential relationships, we conducted MR analysis using publicly available Genome-Wide Association Studies (GWAS) data. Effect estimates were computed using the random-effects inverse-variance weighted method.

RESULTS

Our study demonstrates a negative correlation between DHA levels and AD risk (OR: 0.915, 95% CI: 0.858-0.975, p=0.007). Furthermore, in MR analysis using tumor necrosis factor ligand superfamily member 14 (TNFSF14) levels as an outcome, DHA levels also show a negative association with TNFSF14 levels (OR: 0.933, 95% CI: 0.879-0.990, p=0.022). Subsequently, we performed further analysis to explore the relationship between TNFSF14 and AD risk, revealing a positive correlation (OR: 1.069, 95% CI: 1.005-1.137, p=0.033). This suggests a potential mediating role of TNFSF14 in the impact of DHA on AD risk.

CONCLUSIONS

In summary, our study employs MR analysis to offer genetic evidence indicating a potential role of DHA in reducing the risk of AD, as well as opening avenues for further in-depth investigation into potential mechanisms. These findings emphasize the importance of ongoing research in this field.

Factors influencing the occurrence of hyperuricemia and poor cardiac and renal outcomes in chronic kidney disease

OBJECTIVE

The aim of our study was to analyze the factors influencing the occurrence of hyperuricemia and poor cardiac and renal outcomes in chronic kidney disease (CKD).

PATIENTS AND METHODS

One hundred and sixteen patients with CKD admitted to our hospital from January 2022 to September 2022 were picked as the subjects. Fasting venous blood of these subjects was collected to value the serum uric acid (SUA) levels on an automatic biochemical analyzer. Patients were then grouped as the CKD-only group (n=80) and hyperuricemia group (n=36), according to the SUA results, or the good prognosis group (n=88) and poor prognosis group (n=28), according to the presence of cardiovascular diseases. The changes in laboratory indexes and clinical data were analyzed and compared. Multivariate logistic regression analysis was used to analyze the risk factors for combined hyperuricemia and the risk factors for poor cardiac and renal outcomes in patients with CKD. The correlation between SUA level and cardiac and renal indexes was analyzed by Pearson analysis.

RESULTS

Patients in the CKD hyperuricemia group had markedly higher content of systolic blood pressure (SBP), diastolic blood pressure (DBP), B-type natriuretic peptide (BNP), urinary retinol-binding protein (RBP), urinary N-acetyl-β-D glucosidase (NAG), much higher proportion of heart failure episodes history, and much lower content of total cholesterol (TC), albumin (Alb), hemoglobin (Hb), urinary α1-microglobulin (α1-MG), and glomerular filtration rate (eGFR) than the CKD-only group (p < 0.05). SUA, BNP, SBP, and history of heart failure episodes were independent risk factors for combined hyperuricemia in CKD patients (p < 0.05). Besides, eGFR, albumin, and hemoglobin were independent protective factors for combined hyperuricemia in CKD patients (p < 0.05). Compared with the good prognosis group, the content of BNP, SBP, DBP, urinary RBP, urinary NAG, and SUA was much higher, the proportion of heart failure episodes history was obviously higher, and the levels of Alb, Hb, TC, eGFR, and urinary α1-MG were sharply lower in the poor prognosis group (p < 0.05). SUA, BNP, SBP, and history of heart failure episodes were independent risk factors for poor cardiac and renal outcomes (p < 0.05), and eGFR was an independent protective factor for poor cardiac and renal outcomes in patients with CKD (p < 0.05). The SUA level in CKD patients was positively correlated with BNP and SBP (r=0.463, 0.215, p < 0.05), but negatively correlated with eGFR (r=0.463, 0.215, p < 0.05).

CONCLUSIONS

The serum SUA level was elevated with the aggravation of the CKD stage. High serum SUA level is a risk factor for the development of hyperuricemia and poor cardio-renal outcomes in CKD patients, suggesting that early monitoring of changes in SUA levels may help assess the risk of cardio-renal outcomes in CKD patients.

Outcome of stroke patients eligible to mechanical thrombectomy managed by spoke center, primary stroke center or comprehensive stroke center in the East of France

BACKGROUND AND PURPOSE

Patients with suspected stroke are referred to the nearest hospital and are managed either in a spoke center (SC), a primary stroke center (PSC), or a comprehensive stroke center (CSC) in order to benefit from early intravenous thrombolysis (IVT). In case of large vessel occlusion (LVO), mechanical thrombectomy (MT) is only performed in the CSC, whereas the effectiveness of MT is highly time-dependent. There is a debate about the best management model of patients with suspected LVO. Therefore, we aimed to compare functional and safety outcomes of LVO patients eligible for MT managed through our regional telestroke system.

METHOD

We performed a retrospective analysis of our observational prospective clinical registry in all consecutive subjects with LVO within six hours of onset who were admitted to the SC, PSC, or CSC in the east of France between October 2017 and November 2022. The primary endpoint was the functional independence defined as modified Rankin scale (mRS) score 0 to 2 at 90 days. Secondary endpoints were functional outcome, early neurological improvement, symptomatic intracranial hemorrhage and 90-day mortality.

RESULTS

Among the 794 included patients with LVO who underwent MT, 122 (15.4%) were managed by a SC, 403 (50.8%) were first admitted to a PSC, and 269 (33.9%) were first admitted to the CSC. The overall median NIHSS and ASPECTS score were 16 and 8, respectively. Multivariate analysis did not find any significant difference for the primary endpoint between patients managed by PSC versus CSC (OR 1.06 [95% CI 0.64;1.76], P=0.82) and between patient managed by SC versus CSC (OR 0.69 [0.34;1.40], P=0.30). No difference between the three groups was found except for the parenchymal hematoma rate between PSC and CSC (15.7 versus 7.4%, OR 2.25 [1.07;4.74], P=0.032).

CONCLUSIONS

Compared with a first admission to a CSC, the clinical outcomes of stroke patients with LVO eligible for MT first admitted to a SC or a PSC are similar.

[Epidemiological characteristics and spatio-temporal distribution of pulmonary tuberculosis cases reported in students from Guizhou Province, 2011-2020]

Objective: To analyze the trend of epidemiological characteristics and spatiotemporal distribution of pulmonary tuberculosis (PTB) among smear-positive or other types of students in Guizhou Province from 2011 to 2020, and to provide a reference for improving prevention and control measures. Methods: Data were collected from the Chinese Information System's Notifiable Disease and Tuberculosis Management Information System for disease control and prevention, the Joinpoint 4.9.1.0 software was used to analyze the trend of registration rate; the ArcGIS 10.6 software was used to construct a ring map and to perform spatial autocorrelation analysis; the SaTScan 9.7 software was used for spatial-temporal scan statistics. Results: A total of 32 682 student PTB cases were reported in Guizhou Province from 2011 to 2020, including 5 949 (18.20%) smear-positive cases. Most cases occurred from high school students of 16 to 18 years old (43.99%, 14 376/32 682); the annual average registered rate was 36.22/100 000, the highest in 2018 (52.90/100 000), and the registration rate showed an increasing trend. Meanwhile, a similar trend of registration rate was observed among smear-positive or other types of students. The spatialtemporal heterogeneity was found that the "high-high" clustering patterns of smear-positive or other types were aggregated in Bijie City. Six spatialtemporal clusters with statistically significant (all P<0.001) were detected among smear-positive or other cases, respectively. Conclusions: Upward trend with spatial- temporal clusters of PTB cases reported in students from Guizhou Province from 2011 to 2020. Surveillance should be strengthened for high school students, and regular screening should be conducted in high-risk areas to control the source of infection and reduce the risk of transmission.

Transradial access with Simmons guiding catheter for carotid artery stenting: Feasibility and procedural complications in a single-center experience

BACKGROUND

There is an increasing number of transradial approach (TRA) for carotid artery stenting (CAS), however, similar techniques and materials as for femoral access are used. We report the results of TRA lower profile technique for CAS using a 7 F Simmons guiding catheter, especially in terms of feasibility and procedural safety in a single center.

MATERIALS AND METHODS

We retrospectively analyzed 68 consecutive patients with symptomatic extracranial carotid stenoses who underwent 75 CAS between January 2018 and December 2021. The success and crossover rate, procedural time, fluoroscopy, clinical outcomes, technical considerations, and procedural complications were analyzed.

RESULTS

TRA CAS with Simmons guiding catheter was successful in 67/75 (89.3%) cases, with a 7 (9.3%) crossover rate. Fluoroscopy mean time was 15.8 minutes. Two forearm hematomas were described. No ischemic or surgical site complications were reported.

CONCLUSIONS

In our experience frontline TRA with a 7 F Simmons guiding catheter is feasible with high procedural success and a low rate of access site complications.

MRI parameters for predicting the effect of ultrasound-guided high-intensity focused ultrasound in the ablation of uterine fibroids

AIM

To study the value of magnetic resonance imaging (MRI) parameters in predicting the efficacy of ultrasonic ablation of fibroids.

MATERIALS AND METHODS

A total of 91 patients were divided into groups based on non-perfused volume (NPV) ratio and blood supply type. The preoperative MRI parameters were measured and analysed. A correlation analysis between the MRI parameters and the NPV ratio was performed. Receiver operating characteristic (ROC) curves were used to analyse and determine the cut-off value of MRI parameters to predict the ablation rate of fibroids.

RESULTS

The uterine fibroids group with an NPV ratio <80% and the group with an NPV ratio of ≥80% had significant differences in signal intensity (SI) at MRI T2-weighted imaging (WI), fibroid-to-rectus abdominis SI ratio (SIR) at T2WI, and blood supply type (p<0.05). There were no significant differences in fibroid volume, T2WI signal uniformity, and apparent diffusion coefficient (ADC) values. The ADC value and SI and SIR at MRI T2WI in the group with poor blood supply were lower than those in the group with a rich blood supply (p<0.05). SI at MRI T2WI correlated negatively with the NPV ratio. The cut-off values for SI and SIR at MRI T2WI of fibroids whose NPV ratio exceeds 80% were 220.58 and 1.315, respectively.

CONCLUSION

SI at MRI T2WI and blood supply type could be predictors of the efficacy of ablation. Ultrasonic ablation of fibroids with MRI T2WI hyperintensity and a rich blood supply had poor efficacy.

Morphological analysis of C2-C7 spinous process bifurcation in Chinese population: a study using three-dimensional reconstruction of computed tomography

BACKGROUND

This study aimed to investigate the anatomical morphology of the C2 to C7 spinous process (SP) bifurcation (SPB) in the Chinese population and reveal its potential clinical significance.

MATERIALS AND METHODS

Measurement parameters of the three-dimensional (3D) reconstructions of neck computed tomography scans (n = 92 scans) were retrospectively analysed. The 3D reconstruction and measurements were performed using Mimics Research 19.0 and 3-Matic Research 11.0. Two independent investigators reviewed all the data, including parameters such as the length and angle of the SPB. The effects of age and sex were also analysed.

RESULTS

We identified four morphological types of SPB: fully bifid (n = 252, 45.65%), partially bifid (n = 65, 11.78%), non-bifid (n = 226, 40.94%) and unilateral branch (n = 9, 1.63%). The Kappa coefficients indicated good inter-observer reproducibility (0.776), and the intraclass correlation coefficients (ICC) values demonstrated excellent intra-rater reliability (ICC = 0.9, p < 0.0001) in the classification and measurement of SPB parameters. The percentage of general bifid SP was more than 70% in C2-5 and about 21% in C6, while all C7 SPs presented non-bifid. Morphology was symmetrical in bifid and partially bifid SP, while unilateral SP was not.

CONCLUSIONS

The classification system of SPB in this study proved consistent and reliable, despite the subjective bias. Identifying the cervical level by C6 bifurcation is unreliable, as nearly 80% of C6 SP is non-bifid. Our work provides an accurate and effective anatomical reference for SPB studies in the Chinese population.

BMSC-Derived ApoEVs Promote Craniofacial Bone Repair via ROS/JNK Signaling

Bone defect caused by trauma, neoplasia, congenital defects, or periodontal disease is a major cause of disability and physical limitation. The transplantation of bone marrow mesenchymal stem cells (BMSCs) promotes bone repair and regeneration. However, it has been shown that most BMSCs die within a short period after transplantation. During apoptosis, BMSCs generate a large number of apoptotic cell-derived extracellular vesicles (ApoEVs). This study aims to understand the potential role of ApoEVs in craniofacial bone defect repair and regeneration. First, we confirmed that BMSCs undergo apoptosis within 2 d after transplantation into the defect of the cranium. Abundant ApoEVs were generated from apoptotic BMSCs. Uptake of ApoEVs efficiently promoted the proliferation, migration, and osteogenic differentiation of recipient BMSCs in vitro. ApoEVs from cells in the middle stage of apoptosis were the most efficient to enhance the regenerative capacity of BMSCs. Moreover, a critical size bone defect model in rats was used to evaluate the osteogenic property of ApoEVs in vivo. Local transplantation of ApoEVs promoted bone regeneration in the calvarial defect. Mechanistically, ApoEVs promoted new bone formation by increasing intracellular reactive oxygen species to activate JNK signaling. This study reveals a previously unknown role of the dying transplanted BMSCs in promoting the viability of endogenous BMSCs and repairing the calvarial defects. Since it could avoid several adverse effects and limits of BMSC cytotherapy, treatment of ApoEVs might be a promising strategy in craniofacial bone repair and regeneration.

Effects of nitrogen supply rate on photosynthesis, nitrogen uptake and growth of seedlings in a Eucalyptus/Dalbergia odorifera intercropping system

The introduction of N₂ -fixing species into a Eucalyptus plantation resulted in a successful planting system. It is essential to understand the contribution of nitrogen (N) competition and photosynthetic efficiency to plant dry matter yield to shed more light on the growth mechanism of the Eucalyptus/legume system. We compared N competition, photosynthesis and dry matter yield of Eucalyptus urophylla × E. grandis and the N₂ -fixing tree species Dalbergia odorifera in intercropping and monoculture systems under different N levels. The photosynthesis of E. urophylla × E. grandis was improved, while that of D. odorifera was inhibited in the intercropping system. Intercropped E. urophylla × E. grandis increased the N utilization and the dry matter yield by 6.57-48.46% and 7.59-97.26%, and decreased those of D. odorifera by 10.21-30.33% and 0.48-13.19%, respectively. Furthermore, N application enhanced the competitive ability of E. urophylla × E. grandis relative to D. odorifera and changed the N contents and chlorophyll synthesis to optimize the photosynthetic structure of both species. Our results reveal Eucalyptus for photosynthesis, N absorption and increasing the growth benefit from the introduction of N₂ -fixing species, which hence can be considered to be an effective sustainable management option of Eucalyptus plantations.

A case of atlanto-occipital fusion with other multiple anatomic variations

In the routine anatomic measurement study on Asian dry skulls, a skull of atlanto-occipital fusion with other multiple anatomic variations was observed. The entire right half of the atlas vertebra, including the anterior arch, anterior tubercle, posterior arch, and lateral masses, was fused entirely with the occipital bone, while the left fused partly. Besides the atlanto-occipital fusion, the target skull specimen also includes posterior arch defects of the atlas, metopic suture, wormian bones. So many anatomy variations rarely exist in one specimen. This paper aims to present detailed anatomic case reports and discuss related diseases in an anatomic and clinical study.

Identification of Type H Vessels in Mice Mandibular Condyle

Type H vessel is a specific vessel subtype that is strongly positive for CD31 and endomucin (CD31^hiEmcn^hi). It has already been identified that it can tightly regulate the coupling of angiogenesis and osteogenesis in the long bone of mice and human beings. The long bone is formed through endochondral ossification, which is the same type of process happening in mandibular condyle. Although the ossification of long bone and mandibular condyle has the same developmental process, the existence of type H vessels in the mouse condyle remains unclear. To address this, we identified that abundant type H vessels existed in the subchondral bone of the mouse condylar head and endosteum of the mouse condylar neck. Meanwhile, immunofluorescence imaging of the condyles in different ages of male C57BL/6J mice demonstrated that type H vessels decreased while aging. Furthermore, we validated a positive correlation between type H vessels and Osterix⁺ osteoprogenitors in the condyle induced by mandibular advancement. Mechanistically, we confirmed that deferoxamine mesylate, which promoted the proliferation of type H endothelial cells by activating hypoxia-inducible factor 1α (HIF-1α) signaling pathways, largely prevented the osteopenia in the condyle induced by botulinum toxin type A. Collectively, these results demonstrate that in the mouse condyle, type H vessels in areas of high function positively correlate with bone formation. In addition, we show a novel influence of HIF-1α signaling on osteogenesis via an increase in type H vessels. In conclusion, promoting angiogenesis of type H vessels is a promising strategy for the therapeutic improvement of osteogenesis in mandibular condyle.

Oral Organoids: Progress and Challenges

Oral organoids are complex 3-dimensional structures that develop from stem cells or organ-specific progenitors through a process of self-organization and re-create architectures and functionalities similar to in vivo organs and tissues in the oral and maxillofacial region. Recently, striking advancements have been made in the construction and application of oral organoids of the tooth, salivary gland, and tongue. Dental epithelial and mesenchymal cells isolated from tooth germs or derived from pluripotent stem cells could generate tooth germ-like organoids by self-organization in a specific culture system. Tooth organoids can also be constructed based on tissue engineering principles by seeding stem cells on a scaffold with the bioregulatory functions of odontogenic differentiation. Two main approaches have been used to construct salivary gland organoids: 1) incubation of salivary gland-derived stem/progenitor cells in a 3-dimensional culture system to form the structure of the gland through mimicking regenerative processes and 2) inducing of pluripotent stem cells to generate embryonic salivary glands by replicating the development process. Taste bud organoids can be generated by embedding isolated circumvallate papilla tissue in Matrigel with a mixture of growth factors, while lingual epithelial organoids have been constructed using lingual stem cells in a suitable culture system containing specific signaling molecules. These oral organoids usually maintain the main functions and characteristic structures of the corresponding organ to a certain extent. Furthermore, using cells isolated from patients, oral organoids could replicate specific diseases such as maxillofacial tumors and tooth dysplasia. Until now, oral organoids have been applied in the study of mechanisms of tooth development, pathology and regeneration of the salivary gland, and precision therapeutics for tongue cancer. These findings strongly demonstrate that the organoid technique is a novel paradigm for the study of the development, pathology, and regeneration of oral and maxillofacial tissue.

Effect of sacral neuromodulation on bowel dysfunction in patients with neurogenic bladder

AIM

The aim of this retrospective study was to evaluate the clinical effect of sacral neuromodulation (SNM) on bowel dysfunction in patients with neurogenic bladder using the neurogenic bowel dysfunction (NBD) score.

METHOD

Between July 2012 and July 2019, 41 patients with both neurogenic bladder and bowel dysfunction underwent permanent SNM implantation. The NBD score was used to evaluate the bowel symptoms before the testing phase and at follow-up. The first follow-up was at the time of discharge after permanent implantation. The second follow-up was conducted by telephone after discharge.

RESULTS

The mean NBD score before the testing phase was 11.0 ± 5.83, whilst it significantly decreased to 5.2 ± 5.32 (n = 41, P < 0.05) at the first follow-up (32 ± 3.9 days). Before the testing phase, there were 9 patients with very minor NBD, 10 with minor NBD, 13 with moderate NBD and 9 with severe NBD. At the first follow-up, there were 26 patients with very minor NBD, 7 with minor NBD, 4 with moderate NBD and 4 with severe NBD (P < 0.05). Twenty-six patients were interviewed in the long-term follow-up (34 ± 30.9 months). The NBD score in these 26 patients was 5.6 ± 5.18, which was not significantly different from the NBD score (5.5 ± 5.33) at the first follow-up (n = 26, P > 0.05).

CONCLUSION

SNM facilitates a significant reduction in NBD score in patients with neurogenic bladder and bowel dysfunction. The improvement in NBD symptoms can also be used as a future indicator to determine the clinical efficacy of permanent SNM implantation in the treatment of neurogenic bladder.

Area postrema syndrome as initial manifestation in neuromyelitis optica spectrum disorder patients: A retrospective study

BACKGROUND

Area postrema syndrome (APS) is recognized as a core feature in neuromyelitis optica (NMO) diagnosis. Isolated APS can occur at NMO onset and frequently results in a delay of diagnosis, along with devastating secondary neurologic deficits. To date, few studies have characterized APS-onset neuromyelitis optica spectrum disorder (APSO-NMOSD).

OBJECTIVE

We aimed to describe the clinical and radiologic features of patients with APSO-NMOSD who are initially misdiagnosed in a cohort of patients from Zhengzhou, China.

MATERIALS AND METHODS

We identified 15 patients who presented with APS as an initial manifestation, based on the 2015 international consensus diagnostic criteria for NMOSD, and reviewed their demographic, clinical, laboratory, and magnetic resonance imaging (MRI) data.

RESULT

Fifteen patients (3 men, 12 women) aged 14-50 years old were included in our study. All patients presented with APS that included intractable nausea, vomiting, or hiccups (INVH) as the initial manifestation; many experienced a delay in diagnosis. Serum AQP4 was positive in eleven patients and myelin oligodendrocyte glycoprotein (MOG) in one patient. All patients had a linear medullary lesion or a linear medulla-spinal lesion on sagittal MRI. An "inverted V sign" on axial medulla oblongata images, representing a lesion involving the area postrema, was noted in seven patients in this study.

CONCLUSIONS

APS can occur as a sole and initial manifestation of NMOSD, often leading to misdiagnosis in the early process of disease. Identifying patients with an "inverted V" sign and a linear medullary lesion upon MRI examination can help to quickly identify APS patients and avoid further diagnostic delays.

Inhibition of microRNA-875-5p promotes radioiodine uptake in poorly differentiated thyroid carcinoma cells by upregulating sodium-iodide symporter

BACKGROUND AND AIM

Poorly differentiated thyroid carcinoma (PDTC) is an endocrine malignancy that is challenging to treat due to its limited radioiodine uptake. microRNAs (miRNAs or miRs) have been shown to be useful in treating many types of tumors, including PDTC. This study aims to evaluate the potential effect of miR-875-5p on the radioiodine uptake of PDTC and to clarify the underlying mechanisms.

METHODS

Expression of miR-875-5p and sodium-iodide symporter (NIS) in tissues and cell lines was determined using RT-qPCR. The binding relationship between miR-875-5p and NIS was predicted through in silico analysis and verified by dual-luciferase reporter gene assay. A series of miR-875-5p mimic, miR-875-5p inhibitor, shRNA against NIS, and overexpressed NIS plasmids were introduced into PDTC cells. We then evaluated the cell viability, colony formation, apoptosis, and radioiodine uptake of each PDTC sample via CCK-8 assay, clonogenic assay, flow cytometry, and γ counter, respectively.

RESULTS

miR-875-5p was found to be highly expressed, but NIS was poorly expressed in DTC tissues and PDTC cell lines. NIS was verified to be a target gene of miR-875-5p. Upregulation of miR-875-5p was found to induce PDTC cell proliferation, and reduce apoptosis and radioiodine uptake in vitro through down-regulation of NIS. In an in vivo orthotopic model, the enhancement of miR-875-5p led to the reduction of NIS expression and radioiodine uptake in the thyroid tumors.

CONCLUSIONS

Altogether, the findings of the current study suggest that down-regulated miR-875-5p expression could promote its target gene NIS to increase radioiodine uptake in PDTC, constituting a preventive strategy against PDTC.

MicroRNA-124 regulates lactate transportation in the muscle of largemouth bass (micropterus salmoides) under hypoxia by targeting MCT1

Carbohydrate metabolism switches from aerobic to anaerobic (glycolysis) to supply energy in response to acute hypoxic stress. Acute hypoxic stress with dissolved oxygen (DO) levels of 1.2 ± 0.1 mg/L for 24 h and 12 h re-oxygenation was used to investigate the response of the anaerobic glycolytic pathway in Micropterus salmoides muscle. The results showed that the glucose concentration was significantly lower in muscle, while the lactic acid and pyruvic acid concentrations tended to increase during hypoxic stress. No significant difference was observed in muscle glycogen, and ATP content fluctuated significantly. The activities of gluconeogenesis-related enzymes were slightly elevated, such as phosphoenolpyruvate carboxykinase (PEPCK). The activities of the glycolytic enzymes increased after the induction of hypoxia, such as hexokinase (HK), pyruvate kinase (PK), and lactate dehydrogenase (LDH). Curiously, phosphofructokinase (PFK) activity was significantly down-regulated within 4 h during hypoxia, although these effects were transient, and most indices returned to control levels after 12 h of re-oxygenation. Upregulated hif-1α, ampkα, hk, glut1, and ldh mRNA expression suggested that carbohydrate metabolism was reprogrammed under hypoxia. Lactate transport was regulated by miR-124-5p according to quantitative polymerase chain reaction and dual luciferase reporter assays. Our findings provide new insight into the molecular regulatory mechanism of hypoxia in Micropterus salmoides muscle.

The ophthalmic artery: a new variant involving two branches from the supracavernous internal carotid artery

PURPOSE

We report an extremely rare, double ophthalmic artery configuration.

METHODS

We present 2D- and 3D-angiographic features of an anomalous origin of the ophthalmic artery.

RESULTS

The double ophthalmic artery was the result of the persistence of the primitive dorsal ophthalmic artery combined with the presence of a second orbital artery originating from the supracavernous internal carotid artery, passing through the superior orbital fissure and into the orbit to furnish the muscular, lacrimal and ethmoidal arteries and the medial long posterior ciliary artery.

CONCLUSIONS

A heretofore undocumented instance of ophthalmic artery duplication is presented. Knowledge of such variations is important for the planning of endovascular treatments and the comprehension of unusual angiographic images. Such fine arterial variants may very well be frequent, but difficult to demonstrate on simple 2D angiographies. Multiplanar reconstructions of 3D angiography data make it possible to diagnose rare, but embryologically predictable arterial variants.

[A retrospective analysis of clinical characteristics and mortality risks in elderly patients with acute cholecystitis and cholangitis]

Objective: To analyze the clinical characteristics and explore the risk predictors on mortality in elderly patients with acute cholecystitis and cholangitis. Methods: We conducted a retrospective analysis of elderly patients hospitalized in the Second Medical Center of General Liberation Army Hospital for acute cholecystitis and cholangitis during 2000 to 2018. Clinical data and risk predictors on mortality were assessed. The patients were stratified into three groups based on age:Ⅰ (65-74 years old),Ⅱ (75-84 years old), and Ⅲ (≥85 years old). Logistic regression analysis was used to identify the predictors of mortality. Results: A total of 574 patients were finally enrolled with the mean age 87.6 years including 191 in group Ⅰ, 167 in group Ⅱ, and 216 in group Ⅲ. The main cause of acute cholecystitis and cholangitis was gallstone (76.3%),and the main symptom was abdominal pain (62.9%),followed by chills(62.5%),fever(59.8%),jaundice (47.2%) and septic shock(26.3%). Cholecystitis was the most common diagnosis in groups Ⅰ and Ⅱ,whereas it was cholangitis in group Ⅲ. Percutaneous transhepatic biliary/gallbladder drainage (PTBD/PTGD) and endoscopic retrograde cholangiopancreatography (ERCP) were administrated more frequently in groups Ⅲ. A total of 35 patients (6.1%) died during follow-up. Senior in age (OR=11.1),the Charlson comorbidity index (OR=19.5),cancers (OR=9.6),blood stream infections (OR=7.4),severity of cholecystitis and cholangitis (OR=4.2) were risk factors associated with mortality. Conclusions: Even in the elderly patients with acute cholecystitis and cholangitis,comorbidity is one of the main factors affecting clinical outcomes. Due to the poor performance, this group of population presents more severe disease and undergoes conservative treatment strategies.

Susceptibility-Weighted Angiography for the Follow-Up of Brain Arteriovenous Malformations Treated with Stereotactic Radiosurgery

The criterion standard for assessing brain AVM obliteration postradiosurgery is DSA. To explore the value of susceptibility-weighted angiography, we followed 26 patients with brain AVMs treated by radiosurgery using susceptibility-weighted angiography and DSA. Studies were evaluated by 2 independent readers for residual nidi. Susceptibility-weighted angiography demonstrated good intermodality (κ = 0.71) and interobserver (κ = 0.64) agreement, and good sensitivity (85.7%) and specificity (85.7%). Susceptibility-weighted angiography is a useful radiation- and contrast material-free technique to follow-up brain AVM obliteration postradiosurgery.

Abstract P5-03-11: Sensitivity to cell cycle inhibitors in taxane resistant breast cancer models

Background: The use of anthracycline and taxane chemotherapy has improved overall and disease-free survival in breast cancer. However these agents have significant toxicity. In addition, breast cancers can acquire or possess intrinsic chemoresistance. It is imperative to identify patients who will benefit most from adjuvant taxane treatment and those with resistant tumours who could be spared unnecessary toxicity.

Methods: A panel of in vitro derived cell lines models of taxane resistance were generated by serial culture in escalating doses of either paclitaxel or docetaxel until resistance was achieved. Taxane resistant cells were characterised by 2D growth, cell cycle and apoptosis analyses. Genomic profiling using the NanoString® platform was performed to identify differentially expressed genes. The identification of kinases which target the chemoresistant models was achieved through a small molecule kinase inhibitor screen. Effects of selected target kinases on cell proliferation, cell cycle, apoptosis and protein expression were assessed.

Results:

Resistant cell lines exhibited an IC50 at least 40-fold higher than that of the parental cells and displayed cross-resistance to the non-establishing taxane. Cell cycle analysis revealed taxane treatment failed to induce G2/M arrest in the resistant models. A reduced apoptotic response was demonstrated. Genomic profiling identified pathways associated with the cell cycle as being significantly altered. Dinaciclib, a CDK inhibitor of CDK1, CDK2, CDK5 and CDK9, inhibited taxane resistant cell growth with IC50s comparable to the parental lines. Upon exposure to dinaciclib, cell cycle arrest at G2/M was induced and marked apoptosis demonstrated. A reduction in cyclin B1, PLK1 and pRB was observed by western blotting.

Table 1:Sensitivity of taxane resistant cell lines models to paclitaxel and docetaxelCell line modelPaclitaxel (μM)Docetaxel (μM)MDA-MB-231 Parent0.004 ± 0.0030.002 ± 0.003MDA-MB-231 PACR0.184 ± 0.030.017 ± 0.02MDA-MB-231 DOCR0.414 ± 0.0470.262 ± 0.058MCF7 Parent0.004 ± 0.00050.005 ± 0.001MCF PACR0.769 ± 0.1050.07 ± 0.02

Table 2:Gene ontology enrichment analysis of biological process terms significantly over-represented in MDA-MB-231 PACR cell line modelGO TermP-valueFDRpositive regulation of transcription from RNA polymerase II promoter1.11E-162.44E-13positive regulation of cell proliferation9.99E-161.10E-12activation of cysteine-type endopeptidase activity involved in apoptotic process1.43E-106.27E-08negative regulation of apoptotic process2.13E-095.83E-07extrinsic apoptotic signaling pathway8.33E-091.62E-06cell cycle arrest8.89E-091.62E-06positive regulation of cell migration2.83E-084.42E-06

Conclusion: In this study we identified candidate resistance-associated pathways which were differentially expressed between in vitro derived taxane resistant cell line models and the sensitive parental line. The CDK inhibitor, dinaciclib, demonstrated potent activity against the taxane resistant cell line models. Clinical validation to ascertain the role of dinaciclib as a novel therapeutic in the treatment of chemorefractory breast cancer is required.

Citation Format: Taylor KJ, Lyttle N, Liao L, Gourley C, Cameron DA, Bartlett JM, Spears M. Sensitivity to cell cycle inhibitors in taxane resistant breast cancer models [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 P5-03-11.

Abstract P5-04-24: Molecular stratification of ER+/HER2- breast cancer cell lines to predict sensitivity to targeted agents

Background: Approximately 70% of all breast cancers are estrogen receptor positive (ER+) at diagnosis and are dependent on estrogen signaling for tumour growth and proliferation. Some ER+ breast cancers can be effectively treated with adjuvant endocrine therapies including tamoxifen, but despite favorable improvements in overall survival, resistance to endocrine therapy is common and has been associated with dysregulation of several signaling pathways. These pathways can be targeted with specific inhibitors, many of which are currently under clinical investigation. However currently there is a lack of predictive biomarkers to identify which patients should receive treatment with targeted therapy. The goal of this study was to determine whether alterations in specific signaling pathways can be identified and used to stratify breast cancer cell lines to the most effective experimental treatments.

Methods/Results: Fifteen ER+/HER2- cell lines were characterized using a NanoString PAM50-like assay as well as next generation sequencing and were then stratified according to alterations in three key signaling pathways: CCND/CDK, PI3K/AKT/mTOR and FGFR. High-throughput small-molecule screenings were performed to identify the IC50 values of 24 inhibitors across the strata. Variation in inhibitor sensitivity was observed between cell lines based on molecular alterations. Cell lines with a PIK3CA mutation in combination with a CDK-pathway alteration were more sensitive to CDK inhibitors (50 to 120nM) than cell lines with alterations in the CDK-pathway alone or PIK3CA mutations alone (170nM to &gt;5000nM). In addition, cell lines with the dual alterations demonstrated stronger synergy between CDK and PI3K-pathway inhibitors compared to either alteration alone.

Conclusions: The results suggest that stratification according to molecular alterations in specific signaling pathways may predict sensitivity to targeted inhibitors in a panel of ER+/HER2- luminal breast cancer cell lines. Work is ongoing to identify the optimal synergistic inhibitor combinations for each strata. The ultimate goal is to translate this work into a novel personalized medicine approach, using molecular stratification based on a combination of molecular events in a functional pathway as opposed to single genes.

Citation Format: Bathurst L, Liao L, Crozier C, Lyttle N, Marcellus R, Bayani J, Al-awar R, Bartlett J, Spears M. Molecular stratification of ER+/HER2- breast cancer cell lines to predict sensitivity to targeted agents [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 P5-04-24.

Abstract P3-11-03: Validation of CIN4 in the DBCG 89D clinical cohort

Background: Chromosome instability (CIN) in solid tumours is associated with poor prognosis and results in numerical and structural chromosomal aberrations. Our group previously have developed the CIN signatures and have demonstrated the CIN signatures as prognostic biomarkers in breast cancer cohorts. Furthermore, our work in the BR9601 and MA.5 clinical cohorts CIN4 provided level IIB evidence that CIN4 was predictive of anthracycline sensitivity. An analysis of the DBCG 89D clinical trial was now performed to validate the role of CIN gene expression signatures as a marker of anthracycline sensitivity.

Methods: RNA was extracted from patients in DBCG 89D clinical trial analysed through NanoString technology. The prognostic and predictive values of the signatures on distant relapse-free survival (DRFS) were explored using Cox proportional hazard models. Multivariate models included menopausal status, tumour size, nodal status, ER and Her2 status, histological type and grade, and treatment regimen.

Results: All of the 594 samples available from the DBCG 89D we successfully analysed. CIN25 and CIN70 gene expression signatures did not associate with any of the clinicopathological characteristics tested. In addition, CIN25 and CIN70 were not prognostic or predictive of distant relapse free or breast cancer specific survival in this clinical cohort. Low CIN4 score was associated with ER negativity (p=0.02), HER2 normal expression (p&lt;0.05).

Conclusion: In this study we demonstrated that CIN4 was associated with aggressive disease. We were however in DBCG 89D unable to validate the predictive value of CIN4 concerning anthracycline sensitivity.

Citation Format: Spears M, Jensen M-B, Lyttle N, Liao L, Laenkholm A-V, Ejitlertsen B, Bartlett JM. Validation of CIN4 in the DBCG 89D clinical cohort [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 P3-11-03.

Observation of a Space-Time Crystal in a Superfluid Quantum Gas

Time crystals are a phase of matter, for which the discrete time symmetry of the driving Hamiltonian is spontaneously broken. The breaking of discrete time symmetry has been observed in several experiments in driven spin systems. Here, we show the observation of a space-time crystal using ultracold atoms, where the periodic structure in both space and time is directly visible in the experimental images. The underlying physics in our superfluid can be described ab initio and allows for a clear identification of the mechanism that causes the spontaneous symmetry breaking. Our results pave the way for the usage of space-time crystals for the discovery of novel nonequilibrium phases of matter.

Abstract P2-10-01: Validation that a histone gene signature predicts anthracycline response in early breast cancer

Background: The use of anthracycline-based chemotherapies has improved overall and disease free survival in breast cancer. However, anthracyclines can have significant toxicities including cardiotoxicity and leukemia. It is, therefore, imperative to identify those patients who will benefit from adjuvant anthracycline treatment and patients who could be spared unnecessary toxicities and be considered for alternative adjuvant therapy. Previous work performed by our laboratory identified a histone gene expression signature as a predictive marker of anthracycline benefit in the BR9601 clinical trial. In this study we validate the 18 histone gene signature in the MA.5 clinical trial and examine the role of the signature in individual intrinsic subtypes of breast cancer.

Methods We analysed the CCTG MA.5 clinical trial in a prospectively planned retrospective biomarker approach to validate this signature and tested the role of intrinsic subtyping as predictive markers of anthracycline benefit. RNA was extracted from patients in the MA.5 adjuvant trial evaluating the addition of epirubicin (E) to CMF and analysed using NanoString technology. Log-rank analyses validated the predictive values of the signature on distant relapse-free survival (DRFS). Cox-regression models tested independent predictive value on DRFS in the presence of treatment, age, tumour size, nodal status, HER2, ER status and grade, and treatment by marker interactions.

Results Analysis of the MA.5 clinical cohort revealed that patients whose tumour had low histone gene signature expression experienced increased DRFS (HR: 0.54, 95% CI 0.38-0.76, p=0.001) when treated with CEF compared with patients treated with CMF alone. Conversely, there was no apparent benefit of CEF vs CMF in patients with high histone gene expression signature (HR: 1.01, 95%CI 0.66-1.55, p=0.963). After multivariate analysis and adjustment for HER2, nodal status, age, grade and ER, the treatment by marker interaction for the gene signature was 0.54 (95%CI 0.31-0.94, p=0.030) for DRFS.

The predictive impact of the histone signature was independent of intrinsic subtype.

Conclusion The histone gene expression signature is an independent predictor of anthracycline benefit and could be a potential candidate diagnostic assay for patients with early breast cancer.

Citation Format: Spears M, Kornaga E, Lyttle N, Liao L, Bayani J, Quintayo M-A, Yao CQ, D'Costa A, Boutros PC, Twelves CJ, Pritchard KI, Levine MN, Nielsen TO, Shepherd L, Bartlett JMS. Validation that a histone gene signature predicts anthracycline response in early breast cancer [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 P2-10-01.

Abstract P2-10-04: Targeted sequencing in early breast cancer: Identification of novel candidate mutations predictive of anthracycline benefit

Background The use of chemotherapies such as anthracyclines and taxanes have improved overall and disease free survival in breast cancer. For all patients, anthracyclines can have significant toxicities including cardiotoxicity and leukemia. It is therefore essential to select the subset of patients who will receive the optimal overall benefit from anthracycline therapy and to identify molecular pathways driving resistance. To fully understand the impact of mutations in the context of current breast cancer therapy, requires a comprehensive mapping of key molecular events in the context of treatment. We sequenced 101 genes, that were prioritized based on not only gene frequency, but also taking into account the importance of amino acid substitution, type of mutation and network connectivity, in 692 primary tumours to both identify driver genes and pathway cassettes and to understand their clinical significance in response to anthracycline treatment.

Methods We performed targeted sequencing in patients from the BR9601 (n=374) and CCTG MA.5 (n=703) clinical trials. The BR9601 and MA.5 clinical trials examined the effectiveness of combination chemotherapy consisting of CMF (cyclophosphamide, methotrexate and 5-fluorouracil) with or without epirubicin. DNA was extracted, samples were sequenced using AmpliSeq Technology adapted to Illumina and somatic mutations were called using a novel mutation calling pipeline (ISOWN). A priori analyses were performed using distant recurrence free survival (DRFS) as the primary endpoint.

Results: In 692 successfully analysed samples 509 (73.6%) samples exhibited at least one single nucleotide mutation (range 0-54). 94/101 genes were mutated in at least one patient. Only variants in PIK3CA, TP53, CDH1, TLE6, MLL3 and USH2A were detected in 5% or more of samples. TSC22D1, RB1 and ZNF565 were associated with increased risk of distant relapse in multivariate analyses corrected for clinic-pathological variables. No single genes were predictive of anthracycline treatment compared to CMF in multivariate analyses corrected for clinic-pathological variables. Signaling cassettes/modules were designed based on the pathway database, Reactome. Within the signaling cassettes one module was predictive of anthracycline failure. Patients with one or more mutations in this module had an increased risk of distant relapse (HR 0.52, 95% CI 0.29-0.95, p=0.034) when treated with an anthracycline containing chemotherapy regimen compared to CMF (HR 1.34 95% CI 1.05-1.72, p=0.019).

Conclusions: We successfully performed a signaling pathway-based targeted sequencing analysis within predefined signaling modules. We identified a single signaling cassette linked to anthracycline resistance in early breast cancer. However, further work to validate this study in a separate clinical trial is warranted.

Citation Format: Spears M, Kalatskaya I, Trinh QM, Liao L, Chong TM, Crozier C, Dion D, Heisler L, Timms L, Stein LD, Pritchard KI, Levine MN, Shepherd L, Twelves CJ, Bartlett JMS. Targeted sequencing in early breast cancer: Identification of novel candidate mutations predictive of anthracycline benefit [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 P2-10-04.

Osteochondral Interface Stiffening in Mandibular Condylar Osteoarthritis

Osteoarthritis (OA) of the temporomandibular joint (TMJ) is associated with dental biomechanics. A major change during OA progression is the ossification of the osteochondral interface. This study investigated the formation, radiological detectability, and mechanical property of the osteochondral interface at an early stage, the pathogenesis significance of which in OA progression is of clinical interest and remains elusive for the TMJ. Unilateral anterior crossbite (UAC) was performed on 6-wk-old rats as we previously reported. TMJs were harvested at 4, 12, and 20 wk. The progression of TMJ OA was evaluated using a modified Osteoarthritis Research Society International (OARSI) score system. Osteochondral interface was investigated by quantifying the thickness via von Kossa staining of histological slices and in vivo calcium deposition by calcein injection. Tissue ossification was imaged by micro-computed tomography (CT). Mechanical properties were measured at nanoscale using dynamic indentation. Time-dependent TMJ cartilage lesions were elicited by UAC treatment. Geometric change of the condyle head and increased value of the OARSI score were evident in UAC TMJs. At the osteochondral interface, there was not only enhanced deep-zone cartilage calcification but also calcium deposition at the osseous boundary. The thickness, density, and stiffness of the osteochondral interface were all significantly increased. The enhanced ossification of the osteochondral interface is a joint outcome of the aberrant deeper cartilage calcification at the superior region and promoted formation of subchondral cortical bone at the inferior region. The micro-CT detectable ossification from an early stage thus is of diagnostic significance. Although the environment of the cartilage and subchondral bone could be changed due to the stiffness of the interface, whether or not the stiffened interface would accelerate OA progress remains to be confirmed. With that evidence, the osteochondral interface could be a new diagnostic and therapeutic target of the mechanically initiated OA in the TMJ.

Shapes and Fissility of Highly Charged and Rapidly Rotating Levitated Liquid Drops

We use diamagnetic levitation to investigate the shapes and the stability of free electrically charged and spinning liquid drops of volume ∼1 ml. In addition to binary fission and Taylor cone-jet fission modes observed at low and high charge density, respectively, we also observe an unusual mode which appears to be a hybrid of the two. Measurements of the angular momentum required to fission a charged drop show that nonrotating drops become unstable to fission at the amount of charge predicted by Lord Rayleigh. This result is in contrast to the observations of most previous experiments on fissioning charged drops, which typically exhibit fission well below Rayleigh's limit.

Steroid receptor coactivator-1 can regulate osteoblastogenesis independently of estrogen

Steroid receptor coactivator-1 (SRC-1), a well-studied coactivator of estrogen receptor (ER), is known to play an important and functional role in the development and maintenance of bone tissue. Previous reports suggest SRC-1 maintains bone mineral density primarily through its interaction with ER. Here we demonstrate that SRC-1 can also affect bone development independent of estrogen signaling as ovariectomized SRC-1 knockout (SRC-1 KO) mouse had decreased bone mineral density. To identify estrogen-independent SRC-1 target genes in osteoblastogenesis, we undertook an integrated analysis utilizing ChIP-Seq and mRNA microarray in transformed osteoblast-like U2OS-ERα cells. We identified critical osteoblast differentiation genes regulated by SRC-1, but not by estrogen including alkaline phosphatase and osteocalcin. Ex vivo primary culture of osteoblasts from SRC-1 wild-type and KO mice confirmed the role of SRC-1 in osteoblastogenesis, associated with altered ALPL levels. Together, these data indicate that SRC-1 can impact osteoblast function in an ER-independent manner.

Improvement in detrusor-sphincter dyssynergia by bladder-wall injection of replication-defective herpes simplex virus vector-mediated gene delivery of kynurenine aminotransferase II in spinal cord injury rats

STUDY DESIGN

An experimental study.

OBJECTIVES

To investigate the effect of replication-defective herpes simplex virus (HSV) vectors encoding the kynurenine aminotransferase II (HSVrd-KATII) gene on detrusor-sphincter dyssynergia (DSD) in spinal cord injury (SCI) rats.

SETTING

Beijing, China.

METHODS

Sprague-Dawley rats (240-265 g) were spinalized with complete transaction at the T10 level of the spinal cord. The rats were randomly divided into the following three groups: sham group (n=12, with normal saline); HSVrd group (n=12, with HSVrd) and HSVrd-KATII group (n=12, with HSVrd-KATII). One week after spinalization normal saline, HSVrd or HSVrd-KATII was injected into the bladder walls of the three groups, respectively. Three weeks after virus injection, the urethral pressure profile (UPP) and continuous cystometry were performed under awake conditions and gene expression was evaluated in all of the SCI rats.

RESULTS

In the HSVrd-KATII group, the maximum urethral closure pressure (Pclo.max), maximum voiding pressure (MVP), and the number and amplitude of non-voiding contraction (NVCs) were significantly decreased (34.7-39.1%, 46.7-56.2% and 31.5-32.5%, respectively), along with an increase in voiding efficiency (49.1-52.1%) compared with the sham and HSVrd groups. In addition, the levels of KATII protein and mRNA were significantly increased in the L6-S1 dorsal root ganglia (DRG) and L6-S1 spinal cord segments in the HSVrd-KATII group compared with the HSVrd group.

CONCLUSIONS

HSVrd vector encoding the KATII gene effectively improved DSD and detrusor overactivity by bladder-wall injection, perhaps by blocking N-methyl-d-aspartate receptors in the L6-S1 dorsal root ganglion and L6-S1 spinal cord.

Twist1 promotes breast cancer invasion and metastasis by silencing Foxa1 expression

The heterogeneous breast cancers can be classified into different subtypes according to their histopathological characteristics and molecular signatures. Foxa1 expression is linked with luminal breast cancer (LBC) with good prognosis, whereas Twist1 expression is associated with basal-like breast cancer (BLBC) with poor prognosis owing to its role in promoting epithelial-to-mesenchymal transition (EMT), invasiveness and metastasis. However, the regulatory and functional relationships between Twist1 and Foxa1 in breast cancer progression are unknown. In this study, we demonstrate that in the estrogen receptor (ERα)-positive LBC cells Twist1 silences Foxa1 expression, which has an essential role in relieving Foxa1-arrested migration, invasion and metastasis of breast cancer cells. Mechanistically, Twist1 binds to Foxa1 proximal promoter and recruits the NuRD transcriptional repressor complex to de-acetylate H3K9 and repress RNA polymerase II recruitment. Twist1 also silences Foxa1 promoter by inhibiting AP-1 recruitment. Twist1 expression in MCF7 cells silenced Foxa1 expression, which was concurrent with the induction of EMT, migration, invasion and metastasis of these cells. Importantly, restored Foxa1 expression in these cells largely inhibited Twist1-promoted migration, invasion and metastasis. Restored Foxa1 expression did not change the Twist1-induced mesenchymal cellular morphology and the expression of Twist1-regulated E-cadherin, β-catenin, vimentin and Slug, but it partially rescued Twist1-silenced ERα and cytokeratin 8 expression and reduced Twist1-induced integrin α5, integrin β1 and MMP9 expression. In a xenografted mouse model, restored Foxa1 also increased Twist1-repressed LBC markers and decreased Twist1-induced BLBC markers. Furthermore, Twist1 expression is negatively correlated with Foxa1 in the human breast tumors. The tumors with high Twist1 and low Foxa1 expressions are associated with poor distant metastasis-free survival. These results demonstrate that Twist1's silencing effect on Foxa1 expression is largely responsible for Twist1-induced migration, invasion and metastasis, but less responsible for Twist1-induced mesenchymal morphogenesis and expression of certain EMT markers.

Oral Food Challenges: A Retrospective Review of A Canadian Paediatric Allergy Clinic

BACKGROUND: Food allergies in children can be life threatening and require prompt treatment with epinephrine. The gold standard for food allergy diagnosis is an Oral Food Challenge (OFC).

OBJECTIVES: To demonstrate the safety of OFCs for diagnosing and monitoring food allergies in a Canadian community paediatric population.

DESIGN/METHODS: Retrospective review of 500 paediatric patients that underwent 684 OFCs to a variety of foods from November 2006 to December 2013. Data collected from the patients includes demographics; the food challenged; reasons for the OFC; reactions experienced during the OFC; medical intervention performed; and whether the patient should continue eating the food challenged (OFC success). Anaphylaxis was defined using the World Allergy Organization criteria – i.e. dermatologic and cardiovascular or respiratory involvement after food ingestion; or two of dermatologic, cardiovascular, respiratory or gastrointestinal involvement after a likely allergen; or cardiovascular involvement after a known allergen. Mild reactions involved only 1 non-cardiovascular system; and moderate reactions involved more than 1 non-cardiovascular system, but did not qualify as anaphylaxis. Systems observed included the dermatologic, upper and lower respiratory, gastrointestinal, cardiovascular, and behavioural systems.

RESULTS: Of the 684 OFCs performed, there were 584 OFCs (85.4%) where the patients were successful at eating the food. Reactions occurred in 274 of 684 OFCs (40.1%), including 161 mild reactions (58.8% of reactions), 56 moderate reactions (20.4% of reactions), and 57 anaphylactic reactions (20.8% of reactions). Medical intervention was required in 74 OFCs (27.0% of reactions). All OFCs with no reaction were successful and all OFCs with anaphylaxis were not successful. OFCs with mild and moderate reactions had equivalent odds of being successful (OR [95% CI] = 0.01 [0.0003, 0.08] and 0.006 [0.0001, 0.04], respectively). Most reactions occurred within six hours of exposure to the food (267 of 274 reactions; 97.4%). The most common foods challenged were peanuts, eggs, and cow’s milk. The reasons for the OFCs were to diagnose an allergy (49.7%), monitor outgrowth of a diagnosed allergy (43.7%), or due to a family member having an allergy (6.6%).

CONCLUSION: In this community practice setting, patients undergoing an OFC were able to eat the food afterwards in 85.4% of the cases. Reactions occurred in 40.1% of OFCs. Anaphylaxis occurred in 8.3% of OFCs (57 of 684 OFCs). Most patients reacted within six hours of exposure. The majority of patients undergoing OFCs did not require treatment. OFCs provide a safe environment to diagnose and monitor food allergies in children.

Effects of grafting on key photosynthetic enzymes and gene expression in the citrus cultivar Huangguogan

Grafting influences scion photosynthetic capacity and fruit quality. Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), which strongly affects photosynthetic rate, and Rubisco activase (RCA), which regulates Rubisco activity, are two key photosynthetic enzymes. However, little information is available regarding the effect of grafting on the concentration and expression of Rubisco and RCA in the citrus cultivar Huangguogan. The objective of this study was to investigate the effect of grafting Huangguogan plants onto trifoliate orange, tangerine, and orange on: 1) the concentration of Rubisco and RCA; 2) the mRNA levels of rbcL, rbcS, and rca; and 3) fruit quality. Overall, the results showed that when Huangguogan plants budded on tangerine and orange, they had better fruit quality, while on trifoliate orange they had higher Rubisco concentration. Tangerine and orange are probably the most suitable rootstocks for Huangguogan plants given the environmental conditions of Sichuan Province, China.