Oropharyngeal Cancer Early Outcomes and Challenges During the COVID-19 Pandemic

Purpose/Objective(s)

The COVID-19 pandemic triggered a national emergency which drastically affected the practice of medicine. Studies have already shown that delays in cancer screening/diagnosis/treatment have ensued, and some project this will translate into increased mortality. We aimed to evaluate if early oropharyngeal cancer (OPC) outcomes with radiation therapy (RT) were affected.

Materials/Methods

On 3/17/2020, in response to the crisis in New York City, telemedicine consultations were implemented at our institution and patients followed prospectively. The Covid cohort (COV) includes new patients through July 2020. They were compared to a contemporary pre-Covid (PC) historical cohort of new patients from November 2019 to 3/16/2020. We reviewed medical records and collected clinicopathologic factors for OPC patients treated with curative intent RT. The Kaplan-Meier method was used to estimate time-to-event outcomes.

Results

Median follow-up was 8.6 [1.0-13.8] months for all (5.8 months COV, 10.1 months PC). Both cohorts encompassed ∼19 weeks, but half as many consults were seen during the pandemic (n = 38 COV, n = 78 PC). The COV cohort included: 74% telehealth, 92% definitive RT (no surgery), and 89% chemoRT. The PC cohort included: 0% telehealth, 88% definitive RT (no surgery), and 94% chemoRT. There was no difference in COV vs. PC median times from consultation to simulation (1.1 [0-6.4] weeks vs. 1.4 [0-10.6] weeks) or simulation to RT start (2.1 [1.3-4.9] weeks vs. 2.0 [1.1-9.9] weeks). There was no difference in 6 month outcomes between COV vs. PC cohorts: local control (100% vs. 100%, P = 0.70), regional control 100% vs. 100%, P = 0.70), distant control (95.2% vs. 97.2%, P = 0.91), cancer-specific survival (100% vs. 98.7%, P = 0.48). There was no difference in outcomes between telemedicine vs. in-person consults. There were numerically more patients with very advanced disease during the pandemic: T4 (13.2% COV vs. 7.7% PC) or N3/M1 (5.2% COV vs. 2.6% PC), but differences were not statistically significant due to limited numbers. More patients treated during the pandemic developed grade 3 dysphagia requiring feeding tubes (10.5% COV vs. 5.1% PC), not significant due to limited numbers. No patients diagnosed with COVID (1 before, 2 during, and 5 after RT) had recurrence at last follow-up.

Conclusion

There was no difference in early 6 month outcomes between COV and PC cohorts, no difference in outcomes with telemedicine, and RT delivery was sustained at pre-pandemic timelines. Several important clinical trends were identified in the COV cohort: about half as many consultations were seen during the pandemic, patients appeared more likely to present with very advanced disease, and more patients required feeding tubes during treatment. These findings may have important post-pandemic healthcare delivery implications related to delays in diagnosis, threats to long-term outcomes, and increased supportive care needs.

Mechanical properties of three-dimensionally printed titanium plates used in jaw reconstruction: preliminary study

The aim of this study was to compare the mechanical properties of three-dimensionally (3D)-printed and conventional surgical plates used for the repair of maxillary or mandibular defects under the same experimental conditions, and to provide experimental evidence for the future application and clinical trial of 3D-printed individualized surgical plates. For the experimental group, two groups of surgical plates with thicknesses of 2.0 mm and 2.5 mm were designed and 3D-printed by electron beam melting, using Ti-6Al-4V as raw material. Conventional commercially available surgical plates with the same thickness were adopted as the control group. A Vickers hardness tester and universal testing machine were used to measure the mechanical properties of the plates (hardness, bending strength, tensile strength, and yield strength). The mechanical properties of 3D-printed surgical plates were significantly better than those of conventional surgical plates of the same thickness (P < 0.001). Comparing the surgical plates of different thickness, the 2.5 mm-thick plates had the highest bending strength in the experimental group (P < 0.001) and the best hardness (P < 0.001), bending strength (P = 0.001), tensile strength (P = 0.001), and yield strength (P = 0.001) in the control group. No statistical difference was found between the two kinds of plates in the experimental group in terms of hardness (P = 0.060), tensile strength (P = 0.096), and yield strength (P = 0.496). The 3D-printed surgical plates have better mechanical properties than the conventional ones.

Insight into biosorption of heavy metals by extracellular polymer substances and the improvement of the efficacy: a review

Heavy metals are continuously released into aquatic environments in which they accumulate. This phenomenon endangers public health because heavy metals accumulate along the food chain. However, conventional remediation methods are inefficient, expensive and yield toxic intermediate products, which adversely affect the environment. The discovery of green bio-adsorbents such as microbial extracellular polymer substance (EPS) has quickly attracted considerable worldwide attention because of their low cost, high removal efficiency of heavy metals and industrial availability. Hence, this review considers the sources, hazards and treatment methods of heavy metals pollution, particularly the biosorption mechanism of EPS to heavy metals and the influencing factors of the bio-adsorption process, which are significant in the efficient removal of heavy metals-containing wastewater treatment. This review also focuses on strengthening the process of EPS adsorption of heavy metals, which can further contribute to heavy metals removal. Finally, it has been proposed that improving the yield, stability, selectivity and recoverability of EPS is the key direction of further research.

Optogenetic actuation in ChR2-transduced fibroblasts alter excitation-contraction coupling and mechano-electric feedback in coupled cardiomyocytes: a computational modeling study

With the help of the conventional electrical method and the growing optogenetic technology, cardiac fibroblasts (Fbs) have been verified to couple electrically with working myocytes and bring electrophysiological remodeling changes in them. The intrinsic properties of cardiac functional autoregulation represented by excitation-contraction coupling (ECC) and mechano-electric feedback (MEF) have also been extensively studied. However, the roles of optogenetic stimulation on the characteristics of ECC and MEF in cardiomyocytes (CMs) coupled with Fbs have been barely investigated. In this study, we proposed a combined model composed of three modules to explore these influences. Simulation results showed that (1) during ECC, an increased light duration (LD) strengthened the inflow of ChR2 current and prolonged action potential duration (APD), and extended durations of twitch and internal sarcomere deformation through the decreased dissociation of calcium with troponin C (CaTnC) complexes and the prolonged duration of Xb attachment-detachment; (2) during MEF, an increased LD was followed by a longer muscle twitch and deformation, and led to APD prolongation through the inward ChR2 current and its inward rectification kinetics, which far outweighed the effects of the delaying dissociation of CaTnC complexes and the prolonged reverse mode of Na⁺-Ca²⁺ exchange on AP shortening; (3) due to the ChR2 current's rectification feature, enhancing the light irradiance (LI) brought slight variations in peak or valley values of electrophysiological and mechanical parameters while did not change durations of AP and twitch and muscle deformation in both ECC and MEF. In conclusion, the inward ChR2 current and its inward rectification feature were found to affect significantly the durations of AP and twitch in both ECC and MEF. The roles of optogenetic actuation on both ECC and MEF should be considered in future cardiac computational optogenetics at the tissue and organ scale.

Three Novel Structural Variations at MHC and IL12B Predisposing to Psoriasis

BACKGROUND

Structural variations (SVs, defined as DNA variants ≥50 bp) have been associated with various complex human diseases. However, research to screen the whole genome for SVs predisposing to psoriasis is still lacking.

OBJECTIVES

This study aimed to investigate the association of SVs and psoriasis.

METHODS

We performed a genome-wide screen on SVs using an imputation method on 5 independent cohorts with 45,386 subjects from the Chinese Han population. Fine mapping analysis, genetic interaction analysis and RNA expression analysis were conducted to explore the mechanism of SVs.

RESULTS

We obtained 4,535 SVs in total and identified 2 novel deletions (esv3608550, OR=2.73, P<2.00×10^-308 ; esv3608542, OR=0.47, P=7.40×10^-28 ) at 6q21.33 (MHC), 1 novel Alu element insertion (esv3607339, OR=1.22, P=1.18×10^-35 ) at 5q33.3 (IL12B), and confirmed 1 previously reported deletion (esv3587563, OR=1.30, P=9.52×10^-60 ) at 1q21.2 (LCE) for psoriasis. Fine mapping analysis including SNPs and small Insertions/Deletions (InDels) revealed that esv3608550 and esv3608542 were independently associated with psoriasis, and a novel independent SNP (rs9378188, OR=1.65, P=3.46×10^-38 ) was identified at 6q21.33. By genetic interaction analysis and RNA expression analysis, we speculate that the association of 2 deletions at 6q21.33 with psoriasis might relate to their influence on the expression of HLA-C.

CONCLUSIONS

Our study constructed the most comprehensive SV map for psoriasis thus far and enriched the genetic architecture and pathogenesis of psoriasis as well as highlighted the nonnegligible impact of SVs on complex diseases.

Genetic parameters and weighted single-step genome-wide association study for supernumerary teats in Holstein cattle

Supernumerary teats (SNT) are a common epidermal abnormality of udders in mammals. The SNT negatively affect machine milking ability, udder health, and animal welfare and sometimes act as reservoirs for undesirable bacteria, resulting in economic losses on calves and lactating cows due to the cost of SNT removal surgery, early culling, and low milk yield. This study aimed to analyze the incidence and genetic parameter of SNT and detect SNT-related genes in Chinese Holstein cattle. In this study, the incidence of SNT was recorded in 4,670 Chinese Holstein cattle (born between 2008 and 2017) from 2 farms, including 734 genotyped cows with 114,485 SNPs. The SNT had a total frequency of 9.8% and estimated heritability of 0.22 (SE = 0.07), which were obtained using a threshold model in the studied Chinese Holstein population. Furthermore, we calculated approximate genetic correlations between SNT and the following indicator traits: 12 milk production, 28 body conformation, 5 fertility and reproduction, 5 health, and 9 longevity. Generally, the estimated correlations, such as 305-d milk yield for third parity (-0.55; SE = 0.02) and age at first calving in heifer (0.19; SE = 0.03), were low to moderate. A single-step GWAS was implemented, and 10 genes associated with SNT located in BTA4 were identified. The region (112.70-112.90 Mb) on BTA4 showed the highest genetic variance for SNT. The quantitative trait loci on BTA4 was mapped into the RARRES2 gene, which was previously shown to affect adipogenesis and hormone secretion. The WIF1 gene, which was located in BTA5, was also considered as a candidate gene for SNT. Overall, these findings provide useful information for breeders who are interested in reducing SNT.

Association of maternal gestational weight gain with intellectual developmental disorder in the offspring: a nationwide follow-up study in Sweden

OBJECTIVES

To investigate the association between maternal gestational weight gain (GWG) and offspring's intellectual developmental disorders (IDD); how this association is modified by maternal early-pregnancy BMI.

DESIGN

Population-based cohort study.

SETTING AND POPULATION

All liveborn singletons with information on maternal GWG in the Swedish Medical Register during 1992-2006 (n = 467 485).

METHODS

We used three GWG classifications, (1) Institute of Medicine (IOM) guidelines ('ideal' GWG: maternal underweight = 12.7-18.1 kg; normal = 11.3-15.9 kg; overweight = 6.8-11.3 kg; obesity = 5.0-9.1 kg), (2) LifeCycle project recommendation ('ideal' GWG: maternal underweight = 14.0-16.0 kg; normal = 10.0-18.0 kg; overweight = 2.0-16.0 kg; obesity class I = 2.0-6.0 kg; obesity class II ≤0.0-4.0 kg; obesity class III ≤0.0-6.0 kg) and (3) GWG centiles. Hazard ratio (HR) and 95% CI for offspring's IDD risk using Cox regression.

MAIN OUTCOME MEASURES

IDD was extracted from Swedish National Patient Register (code ICD-9:317-319/ICD-10:F70-F79).

RESULTS

Forty-one per cent of children were born to mothers with excessive GWG, 32.8% with ideal GWG and 26.2% with inadequate GWG according to IOM guidelines. Inadequate GWG was associated with 21% higher risk of offspring's IDD (95% CI 1.11-1.31) relative to ideal GWG. In contrast, when using the LifeCycle classification, children of mothers with inadequate GWG (HR 1.14, 95% CI 1.05-1.24) or excessive GWG (HR 1.09, 95% CI 1.01-1.17) had higher risks of IDD than those of mothers with ideal GWG. When using GWG centiles, extremely low GWG (<20th centile) and low GWG (20th-40th centile) were associated with elevated offspring's IDD risk. Further stratified analysis by maternal early-pregnancy body mass index (BMI) showed that overweight/obese mothers (BMI ≥25 kg/m² ) with extremely excessive GWG (>25 kg) was associated with an increased offspring's IDD.

CONCLUSION

Our findings suggest that inadequate maternal GWG may increase offspring's IDD risk, irrespective of maternal early-pregnancy BMI. Extremely excessive GWG (>25 kg) may increase offspring's IDD risk, but only among mothers with an early-pregnancy BMI ≥25 kg/m² .

TWEETABLE ABSTRACT

Inadequate maternal weight gain during pregnancy may increase the risk of offspring's intellectual disability, regardless of maternal BMI.

Observation of D_{s}^{±}/D^{0} Enhancement in Au+Au Collisions at sqrt[s_{NN}]=200 GeV

We report on the first measurement of charm-strange meson D_{s}^{±} production at midrapidity in Au+Au collisions at sqrt[s_{NN}]=200  GeV from the STAR experiment. The yield ratio between strange (D_{s}^{±}) and nonstrange (D^{0}) open-charm mesons is presented and compared to model calculations. A significant enhancement, relative to a pythia simulation of p+p collisions, is observed in the D_{s}^{±}/D^{0} yield ratio in Au+Au collisions over a large range of collision centralities. Model calculations incorporating abundant strange-quark production in the quark-gluon plasma and coalescence hadronization qualitatively reproduce the data. The transverse-momentum integrated yield ratio of D_{s}^{±}/D^{0} at midrapidity is consistent with a prediction from a statistical hadronization model with the parameters constrained by the yields of light and strange hadrons measured at the same collision energy. These results suggest that the coalescence of charm quarks with strange quarks in the quark-gluon plasma plays an important role in D_{s}^{±}-meson production in heavy-ion collisions.

Alternative wetting boundary condition for the chemical-potential-based free-energy lattice Boltzmann model

The free-energy lattice Boltzmann (LB) method is a multiphase LB approach based on the thermodynamic theory. Compared with traditional free-energy LB models, which employ a nonideal thermodynamic pressure tensor, the chemical-potential-based free-energy LB model has attracted much attention in recent years as it avoids computing the thermodynamic pressure tensor and its divergence. In this paper, we propose an improved wetting boundary condition for the chemical-potential-based free-energy LB model. Different from the original wetting boundary condition in the literature, the improved wetting boundary condition utilizes a surface chemical potential that is compatible with the chemical potential of the fluid domain. Accordingly, the thermodynamic consistency of the chemical-potential-based free-energy LB model can be retained by the improved wetting boundary condition. Numerical simulations are performed for droplets resting on flat and cylindrical surfaces with different contact angles. The numerical results show that the improved wetting boundary condition yields more reasonable results and the maximum spurious velocities are found to be smaller by 2 ∼ 3 orders of magnitude than those produced by the original wetting boundary condition.

P–757 The risk of aspirin and prednisone using in women with antithyroid antibodies undergoing assisted reproductive technology

Study question

Is it safe using aspirin (A) and prednisone (P) before pregnancy among women with antithyroid antibodies (ATAbs) undergoing assisted reproductive technology?

Summary answer

Combination therapy of aspirin and prednisone didn’t improve likelihood of clinical pregnancy, but increased miscarriage rate.

What is known already

Compared with women with negative-ATAb, women with positive-ATAb had a lower live birth rate and a higher miscarriage rate. Insufficient evidence existed to determine whether aspirin and prednisone therapy improved the success of pregnancy following assisted reproductive technology (ART) in ATAb-positive euthyroid women. Aspirin and prednisone were used frequently in clinical practice, but the use of these medicines before pregnancy during ART process is still controversial, and the risks of these medicines were not well understood.

Study design, size, duration

A prospective study involving 268 women with unexplained reason for infertility who tested positive for antithyroperoxidase antibody (TPOAb) and/or thyroglobulin antibody (TgAb) were being treated for infertility at the Second Affiliated Hospital of Zhejiang University School of Medicine, Ningbo Women and Children’s Hospital and People’s Hospital of Jinhua from October 2017 to July 2020. Their TSH level ranged from 0.35–4.0mIU/ml and they all underwent fresh embryo transfer.

Participants/materials, setting, methods

Overall, a total of 268 ATAb-positive women were divided 2 groups: group A: no treatment; B: A+P. Both medicines were used in the lowest effective dose. Between the two groups, we measured oocytes retrieved, fertilization rate, high-quality embryo rate, blastulation rate, cleavage rate,implantation rate, likelihood of clinical pregnancy and miscarriage rate. Kruskal-Wallis test was used in nonnormally distributed variables, and the χ2 test or Fisher exact test was used to compare categorical variables.

Main results and the role of chance

A total of 268 infertile women with unexplained reason who tested positive for TPOAb and/or TgAb were recruited in our study. According to assignment, they were divided into two groups. All women in different groups had the similar age, BMI, number of miscarriage and duration of infertility. Levels of FSH, AMH, TSH, FT4, FT3, fibrinogen and d-dimer were similar in all groups. The use of A+P reduced cleavage rate (F = 23.982, P &lt; 0.001) and implantation rate (F = 4.388, P = 0.036). The fertilization rate (P = 0.407), high-quality embryo rate (P = 0.208) and blastulation rate (P = 0.157) were not influenced by the use of medication. In this study, likelihood of clinical pregnancy (P = 0.066) did not change significantly after therapy, and miscarriage rate (P = 0.042) increased after medical treatment.

Limitations, reasons for caution

Firstly, Aspirin is just one representation of anticoagulation therapy, so additional consideration of low molecular heparin should also be considered. Secondly, further randomized controlled trials of aspirin and prednisone alone are needed.

Wider implications of the findings: In this study, use of A+P showed no positive effect, and reduced cleavage rate and implantation rate, while increased miscarriage rate. So, the use of medication for interfile women should be cautious.

Trial registration number

n/a

[Analysis of six children with 3-methylglutaconic aciduria]

Objective: To explore the clinical characteristics, genotypes and long-term outcomes of individuals with 3-methylglutaconic aciduria. Methods: The clinical features, biochemical data, genetic test results and treatment outcomes of six children with 3-methylglutaconic aciduria admitted to the Department of Endocrinology, Genetics and Metabolism, Xinhua Hospital from February 2017 to February 2019 were retrospectively analyzed and the Gesell developmental diagnosis schedule was performed to evaluate the development of four patients. Results: Among 6 children with 3-methylglutaconic aciduria 2 were males and 4 were females.Four cases had 3-methylglutaconic aciduria type Ⅰ and 2 cases had 3-methylglutaconic aciduria with deafness,encephalopathy, and Leigh-like syndrome. Five of 6 patients were detected by newborn screening among whom 4 remained asymptomatic, and only one had a postmortem diagnosis. Among them, 4 patients remained asymptomatic, while two presented with clinical symptoms such as jaundice and dyspnea and the age of disease onset was 1 and 2 days respectively. The concentration of 3-methylglutaconic acid in urine of all affected individuals was between 22.38 and 77.09 mmol/molCr, which was above the normal value. Genetic tests were performed for all patients. Eleven variants were identified in 2 genes, of which 10 variants were novel and only c.442C>T p.(R148X) has been previously reported; Seven variants (c.656-2delA, EX5-EX6 Del, c.942+3A>G, c.373C>T p.(R125W), c.895-3C>G, c.667C>T p.(R223X) and c.894+5G>A) were in AUH gene. The others (c.548G>A p.(R138Q), c.442C>T p.(R148X), c.1339C>T p.(R447X) and c.973dupA p.(M325Nfs*5) were in SERAC1 gene. After being treated with leucine diet restriction and L-carnitine, 4 patients with AUH gene variation who were from asymptomatic phase developed normally, whereas those 2 patients with SERAC1 gene variation had a poor prognosis. During the follow-up, 2 patients exhibited varying degrees of psychomotor retardation, the rest had normal course of development. Conclusions: There are significant clinical heterogeneities among individuals with 3-methylglutaconic aciduria. The most common pathogenic variants are splicing variations, followed by nonsense, missense and frameshift mutations. Leucine-free diet and oral L-carnitine therapy are effective for some patients. Newborn screening is essential for early diagnosis and improvement of prognosis.

[Inhibition of mitochondrial reactive oxygen species reduces high glucose-induced pyroptosis and ferroptosis in H9C2 cardiac myocytes]

OBJECTIVE

To observe the effect of inhibiting mitochondrial oxidative stress and NLRP3 inflammasomes on high glucose (HG)-induced pyroptosis and ferroptosis in H9C2 cardiac muscle cells and explore the possible interactions between mitochondrial reactive oxygen species (ROS) and inflammasomes.

METHODS

H9C2 cells exposed to high glucose (35 mmol/L) were treated with the mitochondrial antioxidant mitoquinone (MitoQ), the NLRP3 antagonist MCC950, or both MCC950 and rotenone (a mitochondrial electron transport antagonist), and the cell viability was measured with CCK-8 assay. The cellular and mitochondrial ROS levels were measured using CellRox and Mitosox fluorescent probes, respectively. The cellular NLRP3 inflammasome level was detected with immunofluorescence assay, and the expressions of the key proteins related with pyroptosis and ferroptosis were determined with Western blotting.

RESULTS

HG exposure significantly lowered the viability of H9C2 cells (P < 0.01), reduced the expression of GPX4 protein (a key protein related with ferroptosis) (P < 0.01), and increased the fluorescence intensities of NLRP3 (P < 0.01) and ROS (at both the cellular and mitochondrial levels, P < 0.01) and the protein expressions of NLRP3 and GSDMD-NT (P < 0.01). Treatment with either MitoQ or MCC950 significantly increased the viability of HG-exposed cells (P < 0.01), increased GPX4 expression (P < 0.01), and reduced the fluorescence intensities of NLRP3 (P < 0.01) and cellular and mitochondrial ROS (P < 0.01) and the protein expressions of NLRP3 and GSDMD-NT (P < 0.05). Compared with MCC950 treatment, treatment with both MCC950 and rotenone significantly reduced the viability of HG-exposed cells (P < 0.01), lowered GPX4 expression (P < 0.01), and increased the fluorescence intensities of ROS and NLRP3 (P < 0.01) and the protein levels of NLRP3 and GSDMD-NT (P < 0.05).

CONCLUSION

MitoQ inhibits mitochondrial ROS production to reduce HGinduced NLRP3 inflammasome activation and thus suppress pyroptosis and ferroptosis of cardiac muscle cells. There may be an interaction between mitochondrial ROS and NLRP3 inflammasomes.

Whole exome sequencing and system biology analysis support the "two-hit" mechanism in the onset of Ameloblastoma

BACKGROUND

Ameloblastoma is the most frequent odontogenic tumor. Various evidence has highlighted the role of somatic mutations, including recurrent mutation BRAF V600E, in the tumorigenesis of Ameloblastoma, but the intact genetic pathology remains unknown.

MATERIAL AND METHODS

We sequenced the whole exome of both tumor tissue and healthy bone tissue from four mandibular ameloblastoma patients. The identified somatic mutations were integrated into Weighted Gene Co-expression Network Analysis on publicly available expression data of odontoblast, ameloblast, and Ameloblastoma.

RESULTS

We identified a total of 70 rare and severe somatic mutations. We found BRAF V600E on all four patients, supporting previous discovery. HSAP4 was also hit by two missense mutations on two different patients. By applying Weighted Gene Co-expression Network Analysis on expression data of odontoblast, ameloblast, and Ameloblastoma, we found a proliferation-associated gene module that was significantly disrupted in tumor tissues. Each patient carried at least two rare, severe somatic mutations affecting genes within this module, including HSPA4, GNAS, CLTC, NES, and KMT2D. All these mutations had a ratio of variant-support reads lower than BRAF V600E, indicating that they occurred later than BRAF V600E.

CONCLUSIONS

We suggest that a severe somatic mutation on the gene network of cell proliferation other than BRAF V600E, namely second hit, may contribute to the tumorigenesis of Ameloblastoma.

Recent progress in magnetic nanoparticles and mesoporous materials for enzyme immobilization: an update

Enzymes immobilized onto substrates with excellent selectivity and activity show a high stability and can withstand extreme experimental conditions, and their performance has been shown to be retained after repeated uses. Applications of immobilized enzymes in various fields benefit from their unique characteristics. Common methods, including adsorption, encapsulation, covalent attachment and crosslinking, and other emerging approaches (e.g., MOFs) of enzyme immobilization have been developed mostly in recent years. In accordance with these immobilization methods, the present review elaborates the application of magnetic separable nanoparticles and functionalized SBA-15 and MCM-41 mesoporous materials used in the immobilization of enzymes.

[Occurrence of rod fracture and salvage methods after primary surgery of the congenital lumbosacral deformity associated with sacral agenesis]

Objective: To analyze the occurrence of rod fracture after surgery for lumbosacral deformity associated sacral agenesis and discuss the relevant salvage methods. Methods: The clinical records of 19 patients who underwent surgical treatment for lumbosacral deformity associated sacral agenesis from January 2001 to January 2018 were retrospectively reviewed, including 11 boys and 8 girls. The average age was (9.6±5.2) years. The outcomes of surgical correction and internal fixation were evaluated by postoperative regular follow-up. We also recorded the time and position of rod fracture occurrence. The Cobb angle, coronal balance and sagittal balance were measured and compared to analyze the corresponding salvage methods and revision outcomes. Results: Three patients encountered rod fracture during follow-up, so the incidence of rod fracture after surgery for lumbosacral deformity associated sacral agenesis was 15.8%(3/19). Based on their own conditions, we formulated the individualized strategy and performed the revision surgery through the posterior-only approach. The most critical step was abundant bone-grafting and fusion in the defected sacroiliac joint. After revision, the scoliotic Cobb angle improved in two patients (91.5° vs 47.5°, 49.0° vs 28.0°) and coronal balance improved in one patient (40.3 mm vs 24.3 mm). No complication reoccurred during follow-up. Conclusion: The rod fracture after surgery for lumbosacral deformity associated sacral agenesis is quite common, which is probably correlated with its unique deformed structure and biomechanical characteristics. The individualized salvage methods and adequate bone-grafting and fusion for the defected sacroiliac joint will guarantee the reconstruction and maintenance of spine balance after revision.

Tissue at Risk and Ischemic Core Estimation Using Deep Learning in Acute Stroke

BACKGROUND AND PURPOSE

In acute stroke patients with large vessel occlusions, it would be helpful to be able to predict the difference in the size and location of the final infarct based on the outcome of reperfusion therapy. Our aim was to demonstrate the value of deep learning-based tissue at risk and ischemic core estimation. We trained deep learning models using a baseline MR image in 3 multicenter trials.

MATERIALS AND METHODS

Patients with acute ischemic stroke from 3 multicenter trials were identified and grouped into minimal (≤20%), partial (20%-80%), and major (≥80%) reperfusion status based on 4- to 24-hour follow-up MR imaging if available or into unknown status if not. Attention-gated convolutional neural networks were trained with admission imaging as input and the final infarct as ground truth. We explored 3 approaches: 1) separate: train 2 independent models with patients with minimal and major reperfusion; 2) pretraining: develop a single model using patients with partial and unknown reperfusion, then fine-tune it to create 2 separate models for minimal and major reperfusion; and 3) thresholding: use the current clinical method relying on apparent diffusion coefficient and time-to-maximum of the residue function maps. Models were evaluated using area under the curve, the Dice score coefficient, and lesion volume difference.

RESULTS

Two hundred thirty-seven patients were included (minimal, major, partial, and unknown reperfusion: n = 52, 80, 57, and 48, respectively). The pretraining approach achieved the highest median Dice score coefficient (tissue at risk = 0.60, interquartile range, 0.43-0.70; core = 0.57, interquartile range, 0.30-0.69). This was higher than the separate approach (tissue at risk = 0.55; interquartile range, 0.41-0.69; P = .01; core = 0.49; interquartile range, 0.35-0.66; P = .04) or thresholding (tissue at risk = 0.56; interquartile range, 0.42-0.65; P = .008; core = 0.46; interquartile range, 0.16-0.54; P < .001).

CONCLUSIONS

Deep learning models with fine-tuning lead to better performance for predicting tissue at risk and ischemic core, outperforming conventional thresholding methods.

Reduced order integration for the radiation efficiency of a rectangular plate

A reduced order integration is proposed for the prediction of radiation efficiency and radiation impedance for a rectangular plate. The formula is simplified using the spatial windowing approach and avoids the singular point at zero radiation distance. Compared with other formulas using similar approaches, the formulation in this letter is computationally efficient and does not require the assumption of an equivalent square plate to reduce the calculation time.

LncRNA FOXC2-AS1 stimulates proliferation of melanoma via silencing p15 by recruiting EZH2

OBJECTIVE

The aim of this study was to elucidate the role of FOXC2-AS1 in promoting the proliferative ability and inhibiting apoptosis of melanoma by silencing p15, thereafter regulating the progression of melanoma.

PATIENTS AND METHODS

FOXC2-AS1 levels in melanoma patients with or without metastasis and those with the tumor in different stages were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Regulatory effects of FOXC2-AS1 on viability and apoptosis in melanoma cells were assessed, and subcellular distribution of FOXC2-AS1 was analyzed. Subsequently, the interactions of FOXC2-AS1 with EZH2 and SUZ12 were explored by RNA-Binding Protein Immunoprecipitation (RNA-RIP) assay. Through chromatin immunoprecipitation (ChIP) assay, the role of FOXC2-AS1 to regulate p15 transcription by recruiting EZH2 was verified. At last, regulatory effects of FOXC2-AS1/p15 axis on viability and apoptosis in melanoma cells were investigated.

RESULTS

It was found that FOXC2-AS1 was upregulated in melanoma tissues, especially those with metastasis or stage II-IV. Melanoma patients expressing high level of FOXC2-AS1 showed worse survival than those with low level. Knockdown of FOXC2-AS1 inhibited viability, and stimulated apoptosis in A375 and sk-mel-110 cells. Besides, P15 level was upregulated in melanoma cells transfected with si-FOXC2-AS1, and FOXC2-AS1 was mainly distributed in cytoplasm. RNA-RIP assay confirmed that FOXC2-AS1 was mainly enriched in anti-EZH2 and aniti-SUZ12. Knockdown of EZH2 could markedly upregulate protein level of p15 in melanoma cells. Furthermore, it was verified that FOXC2-AS1 inhibited p15 transcription via recruiting EZH2, and the knockdown of p15 could partially reverse the regulatory effects of FOXC2-AS1 on viability and apoptosis in melanoma.

CONCLUSIONS

FOXC2-AS1 stimulates proliferative ability in melanoma via silencing p15.

[Initial exploration of transfusion-free liver transplantation]

Objective: To evaluate the effect of transfusion-free techniques on the prognosis of liver transplant patients. Methods: The recipients of adult liver transplantation at Tianjin First Central Hospital from August to December 2019 were included in the clinical observation. Liver transplantation without allogeneic blood transfusion was performed through anesthesia management techniques such as acute hemodilution or phlebotomy without volume replacement,maintaining decreased baseline central venous pressure and cell saver. According to the actual results,the patients were divided into two groups: transfusion-free group(n=21) and allogeneic transfusion group(n=28). There were 13 males and 8 females aged of (56.3±11.6) years in the transfusion-free group;and there were 16 males and 12 females aged (54.3±14.2)years in the allogeneic transfusion group. The transplant recipients who had not adopted transfusion management strategy from January to July 2019 were included as control group(27 males and 13 females,aged of (58.9±14.1)years). The clinical data of patients in perioperative period were collected to compare whether there were differences in the recovery of liver function and early complications among the three groups, one-way ANOVA test, rank-sum test, and χ² test were used for data analysis. Results: The amount of intraoperative blood loss in both the transfusion-free group and the transfusion group was less than that in the control group((454.2±271.3)ml vs.(673.6±333.4)ml vs.(890.3±346.7)ml;q=-6.342,-5.286,both P<0.05).The duration of stay in ICU of the transfusion-free group was less than that of the transfusion group and control group((36.4±9.1)hours vs.(44.3±14.9)hours vs.(58.2±21.1)hours;q=-4.432,-3.824,both P<0.05).The mean ALT level at 7 days after operation was significantly lower in the transfusion-free group than in the control group((56.8±32.1)U/L vs.(89.6±45.6)U/L;q=-3.358,P<0.05). Conclusions: The improvement of multi-disciplinary transfusion management technology aimed at transfusion-free liver transplantation can effectively reduce intraoperative hemorrhage and help to avoid surgical transfusion. Transfusion-free liver transplantation is beneficial to the early postoperative recovery,and its long-term clinical significance is worthy of further clinical research.

Effect of radiomics from different virtual monochromatic images in dual-energy spectral CT on the WHO/ISUP classification of clear cell renal cell carcinoma

AIM

To investigate the effect of radiomics obtained from different virtual monochromatic images (VMIs) in dual-energy spectral computed tomography (CT) on the World Health Organization/International Association for Urological Pathology (WHO/ISUP) classification of clear cell renal cell carcinoma (ccRCC).

MATERIALS AND METHODS

A retrospective study of 99 ccRCC patients who underwent contrast-enhanced dual-energy CT was undertaken. ccRCC was confirmed at surgery or biopsy and graded according to the WHO/ISUP pathological grading criteria as low grade (n=68, grade I and II) or high grade (n=31, grade III and IV). Radiomics risk scores (RRSs) for differentiating high and low grades of ccRCC were constructed from 11 sets of VMI in (40-140 keV, 10 keV interval) the cortical phase. Receiver operating characteristic (ROC) curves were drawn and the area under the curves (AUCs) was calculated to evaluate the discriminatory power of RRS for each VMI. The Hosmer-Lemeshow test was used to evaluate the goodness-of-fit of each model and the decision curve was used to analyse its net benefit to patients.

RESULTS

The AUC values for distinguishing low-from high-grade ccRCC with RRS of 40-140 keV VMIs were all >0.920. The Hosmer-Lemeshow test showed that the p-values of RRS of VMIs were >0.05, suggesting good fits. In the decision curve analysis, RRS from the 40-140 keV VMIs had similar decision curves and provided better net benefits than considering all patients either as high-grade or low-grade.

CONCLUSIONS

The RRS obtained from multiple VMIs in dual-energy spectral CT have high diagnostic efficiencies for distinguishing between low- and high-grade ccRCC with no significant differences between different VMIs.

CircRNA_010763 promotes growth and invasion of lung cancer through serving as a molecular sponge of miR-715 to induce c-Myc expression

OBJECTIVE

This study aims to investigate the regulatory effect of circRNA_010763 on the growth and invasion of non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

qRT-PCR was performed to detect the expressions of circRNA_010763 and c-Myc in human NSCLC tissues and cells. CCK-8 assay was performed to evaluate the A549 cells proliferation and transwell assay was performed to evaluate the A549 cells migration. The correlation between miR-715 and circRNA_010763 was detected by statistical analysis. Bioinformatics prediction and Luciferase assay were performed to explore the interaction and binding site of circRNA_010763 and miR-715, miR-715 and c-Myc, respectively.

RESULTS

We found that both circRNA_010763 and c-Myc were upregulated in human NSCLC tissues and cells. qRT-PCR and CCK-8 assay showed that circRNA_010763 expression is associated with the proliferation of NSCLC cells. Transwell assay showed that circRNA_010763 regulated the migration ability of NSCLC cells. The bioinformatics prediction and Luciferase assay demonstrated that circRNA_010763 can sponge with miR-715, serving as a molecular sponge to further regulate the expression of c-Myc.

CONCLUSIONS

In this study, we found that circRNA_010763 was highly expressed in human NSCLC tissues, which could promote tumor proliferation, migration and invasion through serving as a molecular sponge by modulating the inhibitory effect of miR-715 on oncogene c-Myc.

Global Polarization of Ξ and Ω Hyperons in Au+Au Collisions at sqrt[s_{NN}]=200 GeV

Global polarization of Ξ and Ω hyperons has been measured for the first time in Au+Au collisions at sqrt[s_{NN}]=200  GeV. The measurements of the Ξ^{-} and Ξ[over ¯]^{+} hyperon polarization have been performed by two independent methods, via analysis of the angular distribution of the daughter particles in the parity violating weak decay Ξ→Λ+π, as well as by measuring the polarization of the daughter Λ hyperon, polarized via polarization transfer from its parent. The polarization, obtained by combining the results from the two methods and averaged over Ξ^{-} and Ξ[over ¯]^{+}, is measured to be ⟨P_{Ξ}⟩=0.47±0.10(stat)±0.23(syst)% for the collision centrality 20%-80%. The ⟨P_{Ξ}⟩ is found to be slightly larger than the inclusive Λ polarization and in reasonable agreement with a multiphase transport model. The ⟨P_{Ξ}⟩ is found to follow the centrality dependence of the vorticity predicted in the model, increasing toward more peripheral collisions. The global polarization of Ω, ⟨P_{Ω}⟩=1.11±0.87(stat)±1.97(syst)% was obtained by measuring the polarization of daughter Λ in the decay Ω→Λ+K, assuming the polarization transfer factor C_{ΩΛ}=1.

[Establishment of animal models of epidermal growth factor receptor inhibitor-related rashes]

OBJECTIVE

To establish animal models epidermal growth factor receptor inhibitor-related skin rashes using cetuximab, gefitinib or erlotinib.

OBJECTIVE

Female SCID mice were randomly divided into blank control group and high-, moderate-, and low-dose cetuximab groups. The mice in control group received intraperitoneal injection of saline, and those in the 3 cetuximab groups were injected with 80, 40, and 20 mg/kg cetuximab (3 times a week for 4 weeks), respectively. The general skin appearance and skin pathologies of the mice were observed. Female BN rats were randomly divided into blank group, ovalbumin group, gefitinib group and erlotinib group, and in the latter 3 groups, the rats were given ovalbumin (1 mg), gefitinib (37.5 mg/kg), and erlotinib (23.5 mg/kg) by lavage once daily for 45 days, respectively. Skin pathologies of the rats were observed, and serum levels of TNF-α, IL-6 and other inflammatory factors were detected using ELISA.

OBJECTIVE

Intraperitoneal injection of cetuximab did not induce typical skin rashes, scabs or obvious skin inflammation in the mice. In female BN rats, lavage of gefitinib caused obvious skin rashes, scabs and exudation, and obvious inflammatory cell infiltration, keratinosis, spinous layer release and epidermal thickening were observed in the skin. No obvious skin inflammation were observed in the rats in the control, ovalbumin or erlotinib groups. While IgE (P=0.061) and TNF-α concentrations (P=0.057) did not differ significantly among the groups, serum levels of IL-6 was significantly higher in gefitinib group than in the blank control group (P=0.016) but similar between erlotinib group and the blank group (P=0.910).

OBJECTIVE

Intraperitoneal injection of cetuximab can not induce epidermal growth factor receptor inhibitor-related skin rashes in SCID mice. Lavage of gefitinib, but not erlotinib, can be used to establish models of epidermal growth factor receptor inhibitor-related rashes in BN rats.

[Clinical features and gene mutations of 6 patients with carnitine palmitoyltransferase 1A deficiency]

The clinical and biochemical data and gene sequencing results of patients with carnitine palmitoyltransferase 1A deficiency were analyzed, in order to improve the understanding of the disease. Six patients (5 males and 1 female, aged from 1 to 8 years old) with carnitine palmitoyltransferase 1A deficiency from Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital between 2008 and 2019 were included. Two cases were detected by neonatal screening and had no clinical symptoms. The remaining 4 cases all showed seizures induced by fever, vomiting or diarrhea. All the 6 patients showed increased serum free carnitine (C0), decreased hexadecanoylcarnitine (C16) and octadecanoylcarnitine (C18), and increased C0/(C16+C18). Meanwhile, compound heterozygous mutations of CPT1A gene were detected in all 6 patients, of which 2 were reported mutations (c.281+1G>A and c.968-8C>T), and 10 were new mutations. The new mutations included 6 missense mutations, 1 nonsense mutation, 1 deletion mutation and 2 splicing mutations. Detection of free carnitine and acyl carnitine by tandem mass spectrometry is helpful for early screening and diagnosis of carnitine palmitoyltransferase 1A deficiency.

MicroRNA-936 promotes proliferation and invasion of gastric cancer cells by down-regulating FGF2 expression and activating P13K/Akt signaling pathway

OBJECTIVE

This study was designed to investigate whether microRNA-936 can be involved in the development of gastric cancer (GCa) by down-regulating FGF2 expression and activating the phosphatidylinositol 3-kinase/protein kinase B (P13K/Akt) signaling pathway.

PATIENTS AND METHODS

Quantitative polymerase chain reaction (qPCR) was carried out to examine microRNA-936 and FGF2 levels in GCa tissue samples and adjacent normal ones, and further in GCa cell lines. After transfection of microRNA-936 inhibitor in GCa cell lines BGC and SGC, cell invasion, and proliferation abilities were evaluated by transwell and cell counting kit-8 (CCK-8) assays, respectively. In addition, the Dual-Luciferase reporting assay was conducted to verify the binding relationship between microRNA-936 and FGF2. After simultaneous transfection of microRNA-936 inhibitor and si-FGF2 in GCa cells, we detected the expression of FGF2/P13K/Akt by performing qPCR and Western blot experiments to further verify the regulation of microRNA-936 on FGF2 and PI3K/AKT pathway.

RESULTS

QPCR detection revealed that microRNA-936 was remarkably up-regulated while FGF2 was conversely down-regulated in GCa tissue samples, indicating a negative correlation between the two. In addition, compared with normal gastric mucosal cells GES, microRNA-936 showed a significant increased expression in GCa cell lines. Meanwhile, down-regulation of microRNA-936 caused a marked reduction in invasive and proliferation ability of GCa cells. Dual-Luciferase reporting assay demonstrated a direct binding of microRNA-936 to FGF2. QPCR and Western blot showed that microRNA-936 can inhibit FGF2 expression and activate the PI3K/AKT pathway at the same time. Further studies found that silencing FGF2 induced an enhancement in cell proliferation and invasiveness, which could be reversed by simultaneous downregulation of microRNA-936. The above observations suggested that microRNA-936 may accelerate the progression of GCa by inhibiting FGF2 expression and activating the PI3K/AKT pathway.

CONCLUSIONS

Overexpression of microRNA-936 can be conducive to the development of GCa, mainly through the down-regulation of FGF2 and activation of the P13K/Akt signaling pathway.

A vascularized bone graft harvested from the dorsal base of the third metacarpal bone for the treatment of scaphoid nonunion

The purpose of this retrospective study was to introduce the use of an alternative vascularized bone graft for treating scaphoid non-union. The vascularized bone graft was harvested from the dorsal base of the third metacarpal bone. From May 2014 to September 2017, 29 patients with scaphoid non-union were treated. Grip and pinch strengths were compared to the contralateral side. The patients rated wrist joint pain on a visual analogue scale. Wrist function was assessed on Mayo Wrist Score. p < 0.05 was considered statistically significant. 18 scaphoids healed at 6 weeks and the other 11 at 16 weeks. Follow-up ranged from 28 to 73 months, for a mean 48 months. At final follow-up, mean wrist flexion had improved from 65° (range, 51°-81°) preoperatively to 72° (range, 61-78°) (p > 0.05), for a contralateral value of 74° (range, 65°-86°). Mean extension had improved from 56° (range, 44°-72°) to 60° (range, 47°-76°) (p > 0.05) for a contralateral value of 66° (range, 52°-80°). Mean wrist pain improved from 4 (range, 3-8) to 2 (range, 0-4) (p < 0.05). Mean pinch strength improved from 6.4 kg (range, 5.2-7.3 kg) to 8.6 kg (6.1-9.9 kg) (p < 0.05). Mayo Wrist Score improved from 49 (range, 10-65) to 92 (range, 70-100) (p < 0.05). Transferring a vascularized bone graft harvested from the base of the third metacarpal bone was an effective alternative for the treatment of scaphoid non-union, achieving bone healing and normal wrist function without significant donor-site morbidity. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

[Efficacy of 1 384 cases of peritoneal carcinomatosis underwent cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy]

Objective: Peritoneal carcinomatosis refers to a group of heterogeneous (primary or secondary) malignancies in the surface of the peritoneum. Cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) is a comprehensive treatment strategy aiming at peritoneal carcinomatosis. This study analyzed the efficacy and safety of CRS+HIPEC in patients with peritoneal carcinomatosis, and explored prognostic factors. Methods: In this descriptive case-series study, the clinicopathological data of 1384 consecutive patients with peritoneal carcinomatosis treated in Zhongnan Hospital of Wuhan University (330 patients) and Shijitan Hospital of Capital Medical University (1054 patients) from January 2004 to January 2020 were collected retrospectively. Treatment patterns of CRS+HIPEC characteristics (operative time, number of resected organs, number of stripped peritoneum, number of anastomosis, and HIPEC regimens), safety [blood loss volume, postoperative severe adverse event (SAE) and treatment outcome], survival time and prognostic factors influencing survival were analyzed. The SAE was defined as grade III-IV adverse event according to the Peritoneal Surface Oncology Group International Textbook. Perioperative period was defined from the day of CRS+HIPEC to postoperative 30th day. OS was calculated from the day of CRS+HIPEC to the date of death or the last follow-up. Kaplan-Meier method was used for survival analysis, and log-rank test was used for comparison between groups. Cox regression model was used to identify the prognostic factors. Results: Among 1384 peritoneal carcinomatosis patients, 529 (38.2%) were male; median age was 55 (10-87) years old; median body mass index (BMI) was 22.6 kg/m(2); peritoneal carcinomatosis of 164 (11.8%) patients were from gastric cancer, 287 (20.7%) from colorectal cancer, 356 (25.7%) from pseudomyxoma peritonei, 90 (6.5%) from malignant peritoneal mesothelioma, 300 (21.7%) from gynecological cancer or primary peritoneal carcinoma, and 187 (13.5%) from retroperitoneal sarcoma, lung cancer, breast cancer, and other rare tumors. The median duration of CRS+HIPEC was 595 (90-1170) minutes, median number of resected organs was 2 (0-10), median number of resected peritoneal area were 4 (0-9), median peritoneal cancer index (PCI) was 21(1-39). Completeness of cytoreduction (CC) score of 0-1 was observed in 857 cases (61.9%). Regarding HIPEC regimens, there were 917 cases (66.3%) with cisplatin plus docetaxel, 183 cases (13.2%) with cisplatin plus mitomycin, 43 cases (3.1%) with adriamycin plus ifosfamide, and the other 240 cases (17.3%) with modified regimens. Perioperative SAE developed in 331 peritoneal carcinomatosis patients (23.9%) with 500 cases, of whom 21 patients (1.5%) died during the perioperative period due to ineffective treatment, while the others recovered after active treatment. During median follow-up time of 8.6 (0.3-82.7) months, there were 414 deaths (29.9%). The median OS was 38.2 months (95% CI: 30.6-45.8), and the 1-, 3-, 5-year survival rate was 73.5%, 50.4% and 39.3%, respectively. The median OS of peritoneal carcinomatosis patients from gastric cancer, colorectal cancer, pseudomyxoma peritonei, malignant peritoneal mesothelioma and female genital cancer or primary peritoneal carcinomatosis was 11.3 months (95% CI: 8.9-13.8), 18.1 months (95% CI: 13.5-22.6), 59.7 months (95% CI: 48.0-71.4), 19.5 months (95% CI: 6.0-33.0) and 51.7 months (95% CI: 14.6-88.8), respectively, and the difference among groups was statistically significant (P<0.001). Univariate and multivariate analyses revealed that the primary gastric cancer (HR=4.639, 95% CI: 1.692-12.724), primary colorectal cancer (HR=4.292, 95% CI: 1.957-9.420), primary malignant peritoneal mesothelioma (HR=2.741, 95% CI: 1.162-6.466), Karnofsky performance status (KPS) score of 60 (HR=4.606, 95% CI: 2.144-9.895), KPS score of 70 (HR=3.434, 95% CI: 1.977-5.965), CC score of 1 (HR=2.683, 95% CI: 1.440~4.999), CC score of 2-3 (HR=3.661,95% CI: 1.956-6.852) and perioperative SAE (HR=2.588, 95% CI: 1.846-3.629) were independent prognostic factors influencing survival with statistically significant differences (all P<0.05). Conclusions: CRS+HIPEC is an effective integrated treatment strategy for patients with peritoneal carcinomatosis, which can prolong survival with acceptable safety. Preoperative evaluation of patients' general condition is necessary and CRS+HIPEC should be carefully considered to perform for patients with preoperative KPS score <80. During the operation, the optimal CRS should be achieved on condition that safety is granted. In addition, it is necessary to prevent perioperative SAE to reduce the risk of death in peritoneal carcinomatosis patients.

Three-dimensional morphological analysis of neocondyle bone growth after fibula free flap reconstruction

The aim of this retrospective study was to verify the three-dimensional morphological change in neocondyle bone growth after fibula free flap (FFF) reconstruction. The independent variables were age, sex, and diagnosis. Outcome variables included the direction and volume of neocondyle bone growth, and the time to a stable neocondyle following bone growth. The outcome variables were measured on postoperative computed tomography scans using iPlan 3.0. Of the 35 patients included, 25 showed neocondyle bone growth. The direction of neocondyle bone growth included the direction of lateral pterygoid traction (DLPT) and the direction towards the glenoid fossa (DGF). The bone growth of the neocondyle showed three patterns: only DLPT (eight patients), only DGF (two patients), and a combination of DLPT and DGF (15 patients). The average volume of bone growth in the 25 patients was 0.479 ± 0.380 cm³. The average volume of neocondyle bone growth was significantly greater in patients aged <18 years (0.746 ± 0.346 cm³) than in patients aged >18 years (0.219 ± 0.191 cm³) (P < 0.001). The time to a stable neocondyle following bone growth was 5.6 months postoperatively. In conclusion, neocondyle bone growth after FFF reconstruction occurred in two different directions, DLPT and DGF. Osteogenesis of the lateral pterygoid muscle affects neocondyle growth with DLPT. Neocondyle bone growth is more marked in paediatric patients than in adults.

Nonmonotonic Energy Dependence of Net-Proton Number Fluctuations

Nonmonotonic variation with collision energy (sqrt[s_{NN}]) of the moments of the net-baryon number distribution in heavy-ion collisions, related to the correlation length and the susceptibilities of the system, is suggested as a signature for the quantum chromodynamics critical point. We report the first evidence of a nonmonotonic variation in the kurtosis times variance of the net-proton number (proxy for net-baryon number) distribution as a function of sqrt[s_{NN}] with 3.1  σ significance for head-on (central) gold-on-gold (Au+Au) collisions measured solenoidal tracker at Relativistic Heavy Ion Collider. Data in noncentral Au+Au collisions and models of heavy-ion collisions without a critical point show a monotonic variation as a function of sqrt[s_{NN}].

A45 A NOVEL PH-SENSITIVE OPIOID ANALGESIC THAT SELECTIVELY INHIBITS NOCICEPTION IN DSS-INDUCED COLITIS

Background

Opioid drugs are used to treat pain in inflammatory bowel disease (IBD) but their side effects can cause serious morbidity. Therefore, we tested a novel opioid analgesic, ±)-N-(3-fluoro-1-phenethylpiperidine-4-yl)-N-phenylpropionamide (NFEPP) which selectively activates peripheral µ-opioid receptors at acidic pH, as occurs in inflamed tissue.

Aims

Evaluate whether NFEPP causes analgesia in the inflamed colon of DSS-colitis mice using both in vitro and in vivo techniques.

Methods

To measure the visceral motor reflex (VMR) in response to colorectal distention, EMG electrodes connected to a telemetric transmitter were implanted in mice (c57BL/6), after 10 days recovery acute dextran sodium sulfate (DSS) colitis was induced (5 days 2.5% DSS, 2 days water). VMR was measured 30 min after s.c. injection of vehicle or 0.2 mg/kg of NFEPP or fentanyl. Motility was assessed by fecal pellet count 1 hour after NFEPP. Colonic tissue pH was evaluated using the SNARF-4F-5 carboxylic acid probe. Excitability of mouse dorsal root ganglia (DRG) neurons was measured by recording the rheobase (minimum input current to fire an action potential) after superfusion of NFEPP (300 nM, 10 min) or vehicle at pH 6.5 or 7.4. Colonic afferent nerve responses to probing with a von Frey filament (1 gm) were examined before and after exposure to NFEPP (300 nM, 5 min superfusion) at pH 6.5 and 7.4 respectively. The data was analyzed with Welch’s t-test, 1- or 2-way ANOVA with post hoc Dunnett or Bonferroni or Tukey’s test.

Results

NFEPP significantly inhibited the VMR in response to distension in mice with colitis compared to vehicle (decreased response by 65%, P&lt;0.001). NFEPP had no effect in control mice. Conversely, fentanyl caused a similar decreased response in both groups (DSS 79% and control 67%, P&lt;0.001). Pelleting was not affected by NFEPP injection in either group compared to vehicle. The pH measurement revealed a more acidic environment in DSS colonic tissue (ΔpH0.37±0.14, P&lt;0.05) compared to controls. In patch-clamp studies, NFEPP decreased DRG excitability at pH 6.5 compared to the baseline and vehicle (increased rheobase 53.84%, P&lt;0.01 and 36.36%, P&lt;0.05 respectively) but had no effect at pH 7.4. In colonic afferent nerve recordings, NFEPP significantly attenuated afferent responses (28.9% P&lt;0.01) to probing at pH 6.5 but also had no effect at pH 7.4.

Conclusions

This pH-selective opioid agonist significantly inhibits pain at the site of inflammation where the tissue pH is acidic but has no effect in tissues where the pH is in the physiological range. Thus, NFEPP could be an effective opioid analgesic in IBD while being devoid of any unwanted side effects.

Funding Agencies

CCC

A10 FOOD ANTIGEN-STRESS INTERACTION LEADS TO INCREASE PAIN SIGNALING IN ILEUM AND COLON VIA STAT6 IN AN IBS MODEL

Background

Abdominal pain can be triggered by food ingestion in IBS patients. Previously we have shown that a food antigen induces local release of immune mediators in the colon that increase dorsal root ganglion (DRG) neuron excitability when there is previous antigen exposure in the presence of psychological stress. However, it is unknown if this effect is limited to the colon. Furthermore, the involvement of histamine in the neuronal hyperexcitability suggests that the stress-food antigen interaction evokes a Th2 immune response. Thus, we sought to investigate the role of STAT6, a transcription factor downstream of Th2 cytokines and important for IgE production.

Aims

1) Determine if stress-food antigen interaction leads to release of mediators within the small intestine that increase DRG neuron excitability. 2) Determine the involvement of STAT6 on neuronal hyperexcitability induced by the stress-food antigen interaction.

Methods

BALB/c mice were exposed to water avoidance stress (WAS) or sham stress (SHAM) for 1 hr daily for 10 days. On day 2–10, mice were exposed to ovalbumin (OVA) or saline (SAL). Seven days later, mice were re-exposed to either OVA or SAL every 2 days for 2 weeks yielding 3 groups: WAS/OVA+OVA, WAS/SAL+OVA, and SHAM/OVA+OVA. STAT6 deficient mice were also exposed to WAS/OVA+OVA protocol. Ileum or colonic supernatants were obtained 4 hours after tissue collection. DRG neurons were incubated overnight with supernatants prior to perforated patch clamp recordings. Neuronal excitability was evaluated by measuring the rheobase (minimum current to elicit an action potential, decreased rheobase indicates increased excitability). Mechanosensitivity of extrinsic afferent nerves innervating distal ileum was examined using ex vivo extracellular afferent nerve recordings. Data was analyzed by one or two-way ANOVA with Bonferroni post-hoc test.

Results

Ileum supernatants from WAS/OVA+OVA mice increased DRG neuron excitability compared to WAS/SAL+OVA and SHAM/OVA+OVA mice (63.3 ± 6.2 pA vs 83.2 ± 5.4 pA, 86.7 ± 4.5 pA, p&lt;0.05). Ileum afferent nerve response to distention was significantly augmented in WAS/OVA+OVA mice compared to WAS/SAL+OVA and SHAM/OVA+OVA (P&lt;0.05, n=4–7). DRG neurons incubated with WAS/OVA+OVA supernatant from STAT6 deficient mice were less excitable compared to neurons incubated with colonic supernatants from wild type mice (86.5 ± 4.1 pA vs 67.6 ± 4.8 pA, p&lt;0.05).

Conclusions

Stress-food antigen interaction releases mediators in both the small intestine and colon to increase nociceptive signaling, an important finding as IBS can involve both areas. The release of excitatory mediators within the gut appears to involve STAT6. Thus, a stress-food antigen interaction evoking a Th2 immune response in the gut may be a mechanism underlying food induced symptoms in IBS.

Funding Agencies

Queen’s University, Department of Medicine