TRPM7 facilitates fibroblast-like synoviocyte proliferation, metastasis and inflammation through increasing IL-6 stability via the PKCα-HuR axis in rheumatoid arthritis

Transient receptor potential melastatin 7 (TRPM7) is a cation channel that plays a role in the progression of rheumatoid arthritis (RA), yet its involvement in synovial hyperplasia and inflammation has not been determined. We previously reported that TRPM7 affects the destruction of articular cartilage in RA. Herein, we further confirmed the involvement of TRPM7 in fibroblast-like synoviocyte (FLS) proliferation, metastasis and inflammation. We observed increased TRPM7 expression in FLSs derived from human RA patients. Pharmacological inhibition of TRPM7 protected primary RA-FLSs from proliferation, metastasis and inflammation. Furthermore, we found that TRPM7 contributes to RA-FLS proliferation, metastasis and inflammation by increasing the intracellular Ca2+ concentration. Mechanistically, the PKCα-HuR axis was demonstrated to respond to Ca2+ influx, leading to TRPM7-mediated RA-FLS proliferation, metastasis and inflammation. Moreover, HuR was shown to bind to IL-6 mRNA after nuclear translocation, which could be weakened by TRPM7 channel inhibition. Additionally, adeno-associated virus 9-mediated TRPM7 silencing is highly effective at alleviating synovial hyperplasia and inflammation in adjuvant-induced arthritis rats. In conclusion, our findings unveil a novel regulatory mechanism involved in the pathogenesis of RA and suggest that targeting TRPM7 might be a potential strategy for the prevention and treatment of RA.

Ginkgolic acid inhibits the expression of SAE1 and induces ferroptosis to exert an anti-hepatic fibrosis effect

BACKGROUND

Finding a drug for early intervention in the hepatic fibrosis process has important clinical significance. Previous studies have suggested SUMOylation as a potential target for intervention in hepatic fibrosis. However, the role of SAE1, a marker of SUMOylation, in hepatic fibrosis is unknown. Additionally, whether ginkgolic acid (GA), a SUMOylation inhibitor, inhibits hepatic fibrosis by inhibiting SUMO1-activating enzyme subunit 1 (SAE1) should be further investigated.

METHODS

Liver tissues of patients with hepatic cirrhosis and a rat model of hepatic fibrosis constructed with CCl4 (400 mg/kg, twice weekly) or TAA (200 mg/kg, twice weekly) were selected, and the degree of hepatic fibrosis was then evaluated using H&E, Sirius red, and Masson's trichrome staining. After knockdown or overexpression of SAE1 in hepatic stellate cells, the expression levels of ferroptosis and hepatic fibrosis markers were measured in vitro. After intervention with a ferroptosis inhibitor, the expression levels were again measured in vivo and in vitro.

RESULTS

We first demonstrated that SAE1 increased in patients with hepatic cirrhosis. Subsequently, testing of the rat hepatic fibrosis model confirmed that GA reduced the expression of SAE1 and improved hepatic fibrosis in rats. Then, we used hepatic stellate cell lines to confirm in vitro that GA inhibited SAE1 expression and induced ferroptosis, and that overexpression of SAE1 or inhibition of ferroptosis reversed this process. Finally, we confirmed in vivo that GA induced ferroptosis and alleviated the progression of hepatic fibrosis, while inhibiting ferroptosis also reversed the progression of hepatic fibrosis in rats.

CONCLUSION

SAE1 is a potential anti-fibrotic target protein, and GA induces ferroptosis of hepatic stellate cells by targeting SAE1 to exert an anti-hepatic fibrosis effect, which lays an experimental foundation for the future clinical application of its anti-hepatic fibrosis effect.

Personalized Computational Causal Modeling of the Alzheimer Disease Biomarker Cascade

BACKGROUND

Mathematical models of complex diseases, such as Alzheimer's disease, have the potential to play a significant role in personalized medicine. Specifically, models can be personalized by fitting parameters with individual data for the purpose of discovering primary underlying disease drivers, predicting natural history, and assessing the effects of theoretical interventions. Previous work in causal/mechanistic modeling of Alzheimer's Disease progression has modeled the disease at the cellular level and on a short time scale, such as minutes to hours. No previous studies have addressed mechanistic modeling on a personalized level using clinically validated biomarkers in individual subjects.

OBJECTIVES

This study aimed to investigate the feasibility of personalizing a causal model of Alzheimer's Disease progression using longitudinal biomarker data.

DESIGN/SETTING/PARTICIPANTS/MEASUREMENTS

We chose the Alzheimer Disease Biomarker Cascade model, a widely-referenced hypothetical model of Alzheimer's Disease based on the amyloid cascade hypothesis, which we had previously implemented mathematically as a mechanistic model. We used available longitudinal demographic and serial biomarker data in over 800 subjects across the cognitive spectrum from the Alzheimer's Disease Neuroimaging Initiative. The data included participants that were cognitively normal, had mild cognitive impairment, or were diagnosed with dementia (probable Alzheimer's Disease). The model consisted of a sparse system of differential equations involving four measurable biomarkers based on cerebrospinal fluid proteins, imaging, and cognitive testing data.

RESULTS

Personalization of the Alzheimer Disease Biomarker Cascade model with individual serial biomarker data yielded fourteen personalized parameters in each subject reflecting physiologically meaningful characteristics. These included growth rates, latency values, and carrying capacities of the various biomarkers, most of which demonstrated significant differences across clinical diagnostic groups. The model fits to training data across the entire cohort had a root mean squared error (RMSE) of 0.09 (SD 0.081) on a variable scale between zero and one, and were robust, with over 90% of subjects showing an RMSE of < 0.2. Similarly, in a subset of subjects with data on all four biomarkers in at least one test set, performance was high on the test sets, with a mean RMSE of 0.15 (SD 0.117), with 80% of subjects demonstrating an RMSE < 0.2 in the estimation of future biomarker points. Cluster analysis of parameters revealed two distinct endophenotypic groups, with distinct biomarker profiles and disease trajectories.

CONCLUSION

Results support the feasibility of personalizing mechanistic models based on individual biomarker trajectories and suggest that this approach may be useful for reclassifying subjects on the Alzheimer's clinical spectrum. This computational modeling approach is not limited to the Alzheimer Disease Biomarker Cascade hypothesis, and can be applied to any mechanistic hypothesis of disease progression in the Alzheimer's field that can be monitored with biomarkers. Thus, it offers a computational platform to compare and validate various disease hypotheses, personalize individual biomarker trajectories and predict individual response to theoretical prevention and therapeutic intervention strategies.

Targeting regulated chondrocyte death in osteoarthritis therapy

In vivo articular cartilage degeneration is an essential hallmark of osteoarthritis (OA), involving chondrocyte senescence, extracellular matrix degradation, chondrocyte death, cartilage loss, and bone erosion. Among them, chondrocyte death is one of the major factors leading to cartilage degeneration. Many studies have reported that various cell death modes, including apoptosis, ferroptosis, and autophagy, play a key role in OA chondrocyte death. Currently, there is insufficient understanding of OA pathogenesis, and there remains a lack of treatment methods to prevent OA and inhibit its progression. Studies suggest that OA prevention and treatment are mainly directed to arrest premature or excessive chondrocyte death. In this review, we a) discuss the forms of death of chondrocytes and the associations between them, b) summarize the critical factors in chondrocyte death, c) discuss the vital role of chondrocyte death in OA, d) and, explore new approaches for targeting the regulation of chondrocyte death in OA treatment.

TRPM7 channel inhibition attenuates rheumatoid arthritis articular chondrocyte ferroptosis by suppression of the PKCα-NOX4 axis

A role for ferroptosis in articular cartilage destruction associated with rheumatoid arthritis (RA) has not been identified. We previously reported transient receptor potential melastatin 7 (TRPM7) expression was correlated with RA cartilage destruction. Herein, we further characterized a role for TRPM7 in chondrocyte ferroptosis. The expression of TRPM7 was found to be elevated in articular chondrocytes derived from adjuvant arthritis (AA) rats, human RA patients, and cultured chondrocytes treated with the ferroptosis inducer, erastin. TRPM7 knockdown or pharmacological inhibition protected primary rat articular chondrocytes and human chondrocytes (C28/I2 cells) from ferroptosis. Moreover, TRPM7 channel activity was demonstrated to contribute to chondrocyte ferroptosis by elevation of intracellular Ca2+. Mechanistically, the PKCα-NOX4 axis was found to respond to stimulation with erastin, which resulted in TRPM7-mediated chondrocyte ferroptosis. Meanwhile, PKCα was shown to directly bind to NOX4, which could be reduced by TRPM7 channel inhibition. Adeno-associated virus 9-mediated TRPM7 silencing or TRPM7 blockade with 2-APB alleviated articular cartilage destruction in AA rats and inhibited chondrocyte ferroptosis. Collectively, both genetic and pharmacological inhibitions of TRPM7 attenuated articular cartilage damage and chondrocyte ferroptosis via the PKCα-NOX4 axis, suggesting that TRPM7-mediated chondrocyte ferroptosis is a promising target for the prevention and treatment of RA.

Worsening hearing was associated with higher β-amyloid and tau burden in age-related hearing loss

Age-related hearing loss (ARHL) represents the frequently occurring disability that affects the elderly worldwide. The recent evidence has calculated ARHL to be most potential risk factor to predict dementia. β-amyloid plaques and tau accumulation in brain are hallmarks pathologic feature of Alzheimer's disease (AD), which is a leading cause resulting in dementia. However, the potential mechanistic associations between ARHL and dementia remains unknown. We performed the present cross-sectional cohort study by enrolling 72 patients from research on hearing as well as the pathologic hallmarks of AD in brain. The exposure of hearing was measured by either word recognition score or mean pure-tone of the superior ear. The brain β-amyloid and tau standardized uptake value ratio (SUVR) were measured by positron emission tomography (PET). The covariates included gender, age, cardiovascular disease, education and hearing aid use. To analyze the association between hearing and β-amyloid/tau, linear regression was used and adjusted for potentially confounding covariates. Our data showed that the mean age was 67.1 ± 2.9 years. After adjusted for all the covariates, SUVR of β-amyloid showed an increase of 0.028 [95% confidence interval (CI) 0.004-0.061; P = 0.026], while that of tau exhibited an increase of 0.026 (95% CI 0.003-0.056; P = 0.033) per mean pure-tone increase by 10 dB (worsening). Likewise, per mean word-recognition score increase by 10%, the SUVR of β-amyloid showed an increase of 0.060 (95% CI 0.008-0.113; P = 0.023), while that of tau exhibited an increase of 0.059 (95% CI 0.009-0.111; P = 0.031). Taken together, our data demonstrates that hearing worsening was related to the increased burdens of β-amyloid as well as tau detected by PET, which were the AD pathological markers.

[Impact of obstructive sleep apnea on the long-term cardiovascular outcomes in patients with acute coronary syndrome]

Objective: To investigate the impact of obstructive sleep apnea (OSA) on long-term cardiovascular outcomes in patients with acute coronary syndrome (ACS). Methods: This is a single-center, prospective cohort study. Between June 2015 to January 2020, consecutive ACS patients hospitalized at Beijing Anzhen Hospital, Capital Medical University were enrolled. All patients underwent portable sleep breathing monitoring, and they were then divided into moderate/severe OSA group (apnea-hypopnea index (AHI)≥15 events/hour) and no/mild OSA group (AHI<15 events/hour). The primary endpoint was major adverse cardiac and cerebrovascular event (MACCE), defined as a composite of cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, ischemia-driven revascularization and hospital admission for unstable angina or heart failure. MACCE were compared yearly by the log-rank test. Multivariable Cox regression analyses were performed to determine the independent predictors of MACCE. Results: A total of 1 927 patients with ACS were enrolled, including 1 629 males (84.5%), aged (56.4±10.5) years. Moderate/severe OSA was present in 1 014 (52.6%) patients. Compared with no/mild OSA group, moderate/severe OSA group exhibited a higher body mass index (P<0.05). Hypertension, prior PCI were more prevalent in moderate/severe OSA group (both P<0.05). The difference of ACS category between the two groups was statistically significant (P=0.021). The rate of patients who underwent PCI and the number of stents were higher in the moderate/severe OSA group. During a 5-year follow-up (median 2.9 years (IQR 1.5-3.6 years)), the cumulative incidence of MACCE was significantly higher in the moderate/severe OSA group than in the no/mild OSA group (34.0% vs. 24.0%, HR=1.346, 95%CI 1.100-1.646, log-rank P=0.004). The cumulative incidence of MACCE remained statistically higher at 4 and 5 year in the moderate/severe OSA group as compared to the no/mild OSA group (33.3% vs. 22.9%, HR=1.397, 95%CI 1.141-1.710, log-rank P=0.001; 34.0% vs. 24.0%, HR=1.341, 95%CI 1.096-1.640, log-rank P=0.004, respectively). Multivariate analysis showed that moderate/severe OSA (HR=1.312, 95%CI 1.054-1.631, P=0.015) was an independent predictor of long-term MACCE in ACS patients. Conclusions: Moderate/severe OSA is observed in more than 52% ACS patients. Moderate/severe OSA is an independent predictor of long-term MACCE.

Effects of oral sialic acid on gut development, liver function and gut microbiota in mice

Sialic acid (N-acetylneuraminic acid), a 9-carbon monosaccharide, has been widely studied in immunology, oncology and neurology. However, the effects of sialic acid on organ and intestinal development, liver function and gut microbiota were rarely studied. In this study, we found that oral sialic acid tended to increase the relative weight of liver and decreased the serum aspartate aminotransferase (GPT) activity. In addition, sialic acid treatment markedly reduced gut villus length, depth, the ratio of villus length/depth (L/D), areas, width and the number of goblet cells. Furthermore, gut microbes were changed in response to oral sialic acid, such as Staphylococcus lentus, Corynebacterium stationis, Corynebacterium urealyticum, Jeotgalibaca sp_PTS2502, Ignatzschineria indica, Sporosarcina pasteurii, Sporosarcina sp_HW10C2, Facklamia tabacinasalis, Oblitimonas alkaliphila, Erysipelatoclostridium ramosum, Blautia sp_YL58, Bacteroids thetaiotaomicron, Morganella morganii, Clostridioides difficile, Helicobacter tryphlonius, Clostridium sp_Clone47, Alistipes finegoldii, [pseudomonas]_geniculata and Pseudomonas parafulva at the species level. In conclusion, oral sialic acid altered the intestinal pathological state and microbial compositions, and the effect of sialic acid on host health should be further studied.

Facial Nerve Schwannoma Extending to Jugular Foramen: A Case Report

Facial nerve schwannoma (FNS) is a benign, slow-growing schwannoma that originates from Schwann cells. Facial nerve schwannoma is the most common tumor of the facial nerve but rare and only accounts for 0.15% to 0.8% of intracranial neurinomas. It may be manifested as asymmetric hearing loss, facial palsy, and hemifacial spasm. A 56-year-old woman was transferred to our department, because of pain behind the right ear and spasm of the right lateral muscle for more than 2 years and pulsatile tinnitus for half a year. Based on the preoperative medical history, physical signs, and auxiliary examination, it was diagnosed with jugular foramen (JF) space-occupying lesion. We removed the tumor through the infratemporal fossa type A approach and found that the tumor originated from the facial nerve. After the tumor resection, sural nerve transplantation was performed. The patient demonstrated postoperative facial palsy (House-Brackman grade VI) and was smoothly discharged after good recovery. Facial nerve schwannoma rarely invades the JF, and the most common tumor in the JF is the glomus jugular tumor, followed by the posterior cranial schwannoma. They have common symptoms, making it difficult to obtain a correct diagnosis. Clinical data, medical history, and auxiliary examinations should be carefully analyzed to avoid misdiagnosis or mistreatment. Infratemporal fossa type A approach is an effective method for treating FNS of JF.

MiR-122-3p regulates the osteogenic differentiation of mouse adipose-derived stem cells via Wnt/β catenin signaling pathway

OBJECTIVE

To explore the regulatory mechanism of micro-ribonucleic acid (miR)-122-3p in the osteogenic differentiation of mouse adipose-derived stem cells (mADSCs).

MATERIALS AND METHODS

The regulatory mechanism of miR-122-3p in the osteogenic differentiation of mesenchymal stem cells was investigated through its overexpression and knockdown.

RESULTS

The overexpression of miR-122-3p inhibited the osteogenic differentiation of mADSCs. On the contrary, its knockdown promoted the osteogenic differentiation of mADSCs. The further study on the molecular mechanism of miR-122-3p regulating mADSCs' osteogenic differentiation showed that the overexpression of miR-122-3p could activate the Wingless and int-1 (WNT)/β-catenin signaling pathway, but the knockdown of miR-122-3p could repress this signaling pathway.

CONCLUSIONS

MiR-122-3p influences the osteogenic differentiation of mADSCs by modulating the WNT/β-catenin signaling pathway.

0727 Study Onthe Effect Of Obstructive Sleep Apnea-hypopnea Syndrome Onperioperative Management Inendoscopic Sinussurgerypatients

Introduction

To determine the frequency of undiagnosed OSA patients in patients received endoscopic sinus surgery (ESS) and to investigate the effect of OSA on the perioperative management in those patients.

Methods

308 patients undergoing ESS from 2017-2019 were enrolled. The patients were divided into two groups according to whether OSA was combined. STOP-Bang questionnaire scoring system was used to classify patients into high risk and low risk for OSA. The differences between perioperative management and complications between the two groups were compared.

Results

308 consecutive cases were included, 46 cases (14.9%) combined with OSA and 108 cases (35.0%) were at high risk of OSA. OSA patients have higher morbidity of hypertension (OR, 2.05; CI, 1.07-3.92; P=0.03), hyperlipidemia (OR, 2.19; CI, 1.06- 4.51; P=0.03), longer hospitalization time(7.0±2.7 vs. 5.4±3.6, P≤0.01) and higher incidence of intubation difficulties (OR, 3.74; CI,1.39-10.1; P=0.01). Patients at high risk of OSA also had increased rates of hypertension, hyperlipidemia, coronary heart disease and post-operative cardiovascular and respiratory complications.

Conclusion

OSA or high scores of STOP-Bang are associated with increased perioperative complications in ESS patients. Preoperative OSA screening should be strengthened to improve the safety and prognosis of ESS surgery.

Support

National Natural Science Foundation of China under Grant [number 81670903]; and Beijing Municipal Administration of Hospitals Ascent Plan under Grant [number DFL20150602]

Long non-coding RNA AC023794.4-201 exerts a tumor-suppressive function in laryngeal squamous cell cancer and may serve as a potential prognostic biomarker

After the expression level of lncRNA AC023794.4-201 was upregulated in 2 laryngeal squamous cell carcinoma (LSCC) cell lines (AMC-HN-8 and TU-212) and LSCC xenografts, the biological function of lncRNA AC023794.4-201 in LSCC was further investigated using in vitro and in vivo experiments, such as cell function experiments and nude mice transplantation. In our previous study, it was demonstrated that the expression level of the long non-coding RNA (lncRNA) AC023794.4-201 were decreased in laryngeal squamous cell carcinoma, particularly in cases of LSCC with lymphatic metastasis. Moreover, low expression levels of AC023794.4-201 were revealed to be an adverse prognostic factor for patients with LSCC. In the present study, lentiviruses were used to overexpress AC023794.4-201 before a series of cell function assays were performed and a xenograft nude mouse model was constructed, in order to further investigate the functions of AC023794.4-201 in LSCC. AC023794.4-201 inhibited the proliferation and the cloning capacity of LSCC cells compared with the negative control group as indicated by real-time cell analysis and the plate colony formation assay. Flow cytometry and transwell migration assays demonstrated that AC023794.4-201 inhibited the migration, induced cell cycle arrest and increased the apoptotic rate of LSCC cells. The results of the in vivo studies demonstrated that AC023794.4-201 significantly inhibited the growth of LSCC xenografts, and promoted apoptosis. In conclusion, the findings of the present study suggested that AC023794.4-201 may exert tumor-suppressive functions in the progression of LSCC and may serve as a potential prognostic biomarker for LSCC.

In-vivo assessment of T cell kinetics in individuals at risk for type 1 diabetes

We previously assessed the kinetics of T cell turnover in vivo by labeling cells with ² H-H₂ O over 42 days in individuals with type 1 diabetes (T1D) and demonstrated an increased turnover of CD4 memory T cells. We have now tested T cell turnover in individuals at risk for T1D using a 3-4-day labeling protocol with ² H-glucose. We studied 30 relatives with T1D with and without autoantibodies, and 10 healthy controls. Peripheral blood mononuclear cells (PBMC) were flow-sorted into T cell subsets of interest; ² H-DNA enrichment was measured by mass spectrometry and in-vivo turnover was calculated as maximum fractional enrichment of deuterated adenosine (F_max ). Among CD4⁺ cells, F_max was highest in regulatory T cells (T_reg ), followed by effector and central memory T cells and lowest in naive cells. Similarly, CD8⁺ central and effector memory T cells had a higher turnover than CD8⁺ terminally differentiated effector memory T cells (TEMRA) and CD8⁺ -naive T cells. Relatives as a group showed significantly increased T_reg turnover by F_max compared to controls (1·733 ± 0·6784% versus 1·062 ± 0·3787%, P = 0·004), suggesting pre-existing immune dysfunction within families with T1D. However, there was no significant difference in F_max between groups according to autoantibody or glucose tolerance status. Repeat testing in 20 subjects 1 year later demonstrated relatively higher within-subject compared to between-subject variability for the measurement of F_max in various T cell subsets. The short labeling protocol with ² H-glucose should be applied in the context of a clinical trial in which the therapy is expected to have large effects on T cell turnover.

Expression of the long noncoding RNA RP11-169D4.1-001 in Hypopharyngeal Squamous cell carcinoma tissue and its clinical significance

Background

Increased research efforts have demonstrated that lncRNAs are associated with multiple head and neck tumors and play important roles in cancer. We previously found that RP11‐169D4.1‐001 plays a tumor‐suppressive role in laryngeal cancer, but its function in human hypopharyngeal squamous cell carcinoma (HSCC) remains unknown. Thus, this research aimed to analyze the relationship between RP11‐169D4.1‐001 expression and HSCC clinicopathological features.

Methods

Real‐time quantitative reverse transcription‐polymerase chain reaction (qRT‐PCR) was used to detect the expression of RP11‐169D4.1‐001 in 70 pairs of HSCC and adjacent normal tissues.

Results

The expression level of RP11‐169D4.1‐001 in HSCC tissues was significantly lower than that in adjacent normal tissues (P = .001). The expression of RP11‐169D4.1‐001 had no significant relationship with tumor differentiation, stage, smoking, drinking, age, tumor location, or treatment. RP11‐169D4.1‐001 expression was associated with T category (P = .008) and lymph node metastasis (P = .001). Survival data were assessed by Kaplan‐Meier curves. Patients with high RP11‐169D4.1‐001 expression were found to have a shorter overall survival than patients with low RP11‐169D4.1‐001 expression. Multivariate analysis also indicated that target RNA was an independent factor for prognosis. The ROC curve was constructed to clarify the diagnostic value of RP11‐169D4.1‐001.

Conclusions

RP11‐169D4.1‐001 may serve as a new biomarker and potential drug target and can be used as a new biomarker and a potential drug target for the detection and treatment of hypopharyngeal cancer, respectively. Furthermore, RP11‐169D4.1‐001 expression may be an independent prognostic factor affecting the survival of hypopharyngeal cancer patients.

ESRRG promoter hypermethylation as a diagnostic and prognostic biomarker in laryngeal squamous cell carcinoma

Background

Estrogen‐related receptor gamma (ESRRG) has been identified as a tumor suppressor gene in several cancers. We aimed to evaluate ESRRG promoter methylation in laryngeal squamous cell carcinoma (LSCC) and its relative clinical value in LSCC.

Methods

Bisulfite pyrosequencing assays were performed on 91 pairs of tumor and paracancer tissues from LSCC patients in China. The diagnostic value and overall survival (OS) were analyzed descriptively by receiver operating characteristic (ROC) curves and the Kaplan‐Meier methods, respectively.

Results

The ESRRG promoter was more frequently hypermethylated in tumor tissues than in adjacent tissues (P < 0.01). ESRRG promoter methylation was significantly increased in advanced T stage tumors (P < 0.01) and advanced clinical stage patients (P < 0.01). Moreover, the area under the ROC curve (AUC) value (0.81) indicated high discrimination accuracy. Furthermore, ESRRG hypermethylation was associated with poor OS, as confirmed by Kaplan‐Meier survival curves (P < 0.01).

Conclusion

Our study indicated that ESRRG promoter hypermethylation contributed to LSCC‐related risks, primarily tumor progression and survival prognosis, in patients. ESRRG promoter methylation could, therefore, be a diagnostic and prognostic biomarker in LSCC.

Abstract P1-18-03: Phase I trial to assess the safety, pharmacokinetics and pharmacodynamics of receptor activator of nuclear factor-κB ligand inhibitor (TK006) in patients with bone metastases from breast cancer

Background

Within the bone microenvironment, tumor cells secrete factors that stimulate osteoblasts to express and secrete receptor activator of nuclear factor-κB ligand (RANKL), which binds to its receptor RANK on the surface of osteoclasts, thus enhancing the osteoclast-mediated bone resorption and promoting skeletal complications.TK006 is a fully human monoclonal antibody that binds and inhibits RANKL, thus inhibiting osteoclast-mediated bone destruction.

Objective

To investigate the safety, pharmacokinetics and pharmacodynamics of TK006 in patients with bone metastases from breast cancer.

Patients and methods

In this dose-escalating study, patients were sequentially enrolled into 60 mg, 120 mg, 180 mg single-dosing and 120 multiple-dosing cohorts. Before making dose escalation decision, the safety of TK006 during the 14-day period after dosing in the prior cohort must be confirmed. In the three single-dosing cohorts, patients were followed up for 16 weeks after dosing. In the 120 mg multiple-dosing cohort, patents were treated with 120 mg TK006 every 4 weeks for 3 times totally, and followed up for 20 weeks after the first dosing. The primary outcome was safety profile, and the secondary outcomes were pharmacokinetics, pharmacodynamics and immunogenicity. Pharmacodynamics was measured by level of serum bone alkaline phosphatase (BALP) and urine creatinine corrected cross-linked N-telopeptides of type I collagen (uNTX/Cr).

Patients aged 18 to 65 years with breast cancer related bone metastasis were eligible. It was planned to enroll 10 subjects in each cohort for a total sample size of 40 subjects.

Result

As of May 24 2018, the common adverse events (AEs) related to treatment (≥10%) included: hypocalcemia (25.0%), limbs pain (20.0%), gamma-glutamyl transferase increased (17.5%), lactate dehydrogenase increased (12.5%), alpha-hydroxybutyric dehydrogenase increased (12.5%), aspertate aminotransferase increased (12.5%), alanine aminotransferase (10.0%),osphyalgia (10.0%) toothache (10.0%) and hypertriglyceridemia (10%). Most adverse reactions were mild or moderate except one case of grade 3 hypertriglyceridemia and two cases of grade 3 gamma-glutamyl transferase increasement. No esteonecrosis of the jaw or treatment-related SAE was reported.

In the 60 mg single-dosing cohort, a significant reduction in median uNTX/Cr was observed as early as day 1, the nadir of median uNTX/Cr was reach at day 28 and started to return towards the baseline level at day 112 (Table 1).

Only modest decreasing from baseline in median bone-specific alkaline phosphatase was observed.

Table 1.Effects of 60 mg TK006 therapy on bone turnover markers uNTX/Cr, % change from baseline, medianBALP , % change from baseline, medianD1-38.6-4.7D7-63.01.7D14-55.30.2D28-69.2-0.2D56-57.9-12.1D84-33.4-0.4D1121.3-18.7

Ostalgia was measured by visual analogue scale (VAS). In the 60 mg single-dosing cohort, scores were reduced to 2 from 5 and 3 in two patients individually. No increasing in pain was observed in the remaining 8 patients.

Conclusion

These results suggested a potential therapeutic role for TK006 in patients with bone metastases from breast cancer.

Citation Format: Mei YY, Hai TJ, Wei L, Xiang H, Hao W, Ming ZX, An LX. Phase I trial to assess the safety, pharmacokinetics and pharmacodynamics of receptor activator of nuclear factor-κB ligand inhibitor (TK006) in patients with bone metastases from breast cancer [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 P1-18-03.

[Association between hypothyroidism and sleep breathing disorders in patients with coronary heart disease]

Objective: To explore the association between hypothyroidism and sleep breathing disorders in patients with coronary heart disease (CHD). Methods: A total of 784 patients with CHD were consecutively enrolled at the Emergency & Critical Care Center of Beijing Anzhen Hospital from June 2015 to May 2017. According to thyroid function test results, patients were divided into hypothyroidism group (79 cases) and non-hypothyroidism group (705 cases). All patients had undergone sleep monitoring. The sleep apnea status was compared between the two groups. Multivariate logistic regression and linear regression models were used to analyze the association between hypothyroidism and sleep breathing disorders in patients with CHD. Results: The proportion of females, mean body weight and body mass index in the hypothyroidism group were higher than those in the non-hypothyroidism group [26.6% vs.16.2%, (78.6±11.6) kg vs. (75.7±12.0) kg, (27.7±3.2) kg/m(2) vs. (26.6±3.5) kg/m(2), all P<0.05]. Patients in hypothyroidism group had a decreased average oxygen saturation (SaO(2)) compared with patients in non-hypothyroidism group [ (93.2±2.9) % vs. (93.9±2.0) %, P=0.030]. In addition, events of hypoventilation in hypothyroidism group were significantly higher than those in non-hypothyroidism group[92.5 (45.8, 758.3) times vs. 68.0 (33.0, 125.0) times, P=0.013]. There were no significant differences in apnea hypopnea index, diagnosis of obstructive sleep apnea and other sleep breathing parameters between the two groups (P>0.05). A multiple linear regression analysis found that in patients with CHD, the correlation between hypothyroidism and average sleep SaO(2) was significant (β=-0.508, 95%CI -0.989--0.026, P=0.039). Conclusions: CHD patients with hypothyroidism had a lower sleep average SaO(2), and a higher sleep hypopnea events. There is a correlation between hypothyroidism and sleep hypoxia in patients with CHD. Clinical trial registration: clinicalTrials.gov, NCT03362385.

LZTS2 promoter hypermethylation: a potential biomarker for the diagnosis and prognosis of laryngeal squamous cell carcinoma

BACKGROUND

LZTS2 (leucine zipper tumor suppressor 2), a candidate tumor suppressor gene, suppresses cell growth and plays a vital role in the carcinogenesis and development of tumors. No studies to date have described methylation of the LZTS2 promoter in human cancers, including LSCC (laryngeal squamous cell carcinoma). Therefore, the aim of this study was to explore the relationship between LZTS2 promoter methylation and risk of LSCC.

METHODS

In our study, LZTS2 promoter methylation levels in LSCC tumor and adjacent normal tissues from 96 patients were measured using quantitative methylation-specific polymerase chain reaction (qMSP) assays.

RESULTS

The qMSP analyses revealed that LZTS2 promoter methylation levels in the LSCC tumor samples were significantly higher than those in paired adjacent healthy tissue samples. Furthermore, LZTS2 methylation levels were elevated in smokers, advanced T classified, and clinically staged patients, as well as in patients with lymph node metastases. In addition, Kaplan-Meier survival curves results showed that overall survival of LSCC patients with hypomethylated LZTS2 promoters was significantly higher than that in patients with hyper-methylated LZTS2 promoters (log-rank test P = 0.028). Meanwhile, the area under the receiver operating characteristic curve was 0.920. The diagnostic threshold value for LZTS2 methylation was 11.63% (94.7% sensitivity and 80.4% specificity).

CONCLUSIONS

LZTS2 promoter hypermethylation is associated with risk, progression, and prognosis of LSCC in a cohort of 96 human subjects; LZTS2 promoter hypermethylation is a candidate diagnostic and prognostic biomarker for LSCC.

Long non-coding RNA AC026166.2-001 inhibits cell proliferation and migration in laryngeal squamous cell carcinoma by regulating the miR-24-3p/p27 axis

Long non-coding RNA (lncRNA) AC026166.2-001 was found to be down-regulated in laryngeal squamous cell carcinoma (LSCC) tissues and metastatic neck lymph nodes. Decreased AC026166.2-001 was associated with poorer prognosis and may act as a novel biomarker for LSCC patients. In this study, AC026166.2–001 was overexpressed by a lentivirus vector and down-regulated by a small interfering RNA (siRNA). The results of real-time cell analysis (RTCA) and a plate colony formation assay showed that AC026166.2–001 inhibited LSCC cell proliferation and the clone-forming capacity. Cell cycle distribution and related protein changes were measured by flow cytometry. AC026166.2–001 arrested the cell cycle at the G1 phase and induced apoptosis. In addition, AC026166.2–001 decreased cell migration as measured by wound healing assays and transwell migration assays. Moreover, luciferase reporter assay and Western blotting results suggested that AC026166.2–001 acts as a sponge of miR-24-3p and regulates the expression of p27 and cyclin D1. The in vivo results showed that AC026166.2–001 significantly suppressed the growth of LSCC xenografts and promoted apoptosis. We validated the molecular mechanisms underlying AC026166.2–001 in LSCC. This is the first report of AC026166.2–001 acting as a tumor suppressor in LSCC by regulating the miR-24-3p/p27 axis.

Enhanced energy transfer in heterogeneous nanocrystals for near infrared upconversion photocurrent generation

The key to produce inorganic heterogeneous nanostructures, and to integrate multiple functionalities, is to enhance or at least retain the functionalities of different components of materials. However, this ideal scenario is often deteriorated at the interface of the heterogeneous nanostructures due to lattice mismatches, resulting in downgraded performance in most hybrid nanomaterials. Here, we report that there is a narrow window in controlling temperature in a Lewis acid-base reaction process to facilitate epitaxial alignment during the synthesis of hybrid nanomaterials. We demonstrate a perfectly fused NaYF₄:Yb,Tm@ZnO heterogeneous nanostructure, in which the semiconductor ZnO shell can be epitaxially grown onto lanthanide-doped upconversion nanoparticles. By achieving a matched crystal lattice, the interface defects and crystalline grain boundaries are minimized to enable more efficient energy transfer from the upconversion nanoparticles to the semiconductor, resulting in both enhanced upconversion luminescence intensity and superior photoelectrochemical properties. This strategy provides an outstanding approach to endow lanthanide-doped upconversion nanoparticles with versatile properties.

Forty-one cases of round ligament varicosities that are easily misdiagnosed as inguinal hernias

PURPOSE

To demonstrate the benefit and safety of conservative therapy for round ligament varicosities (RLVs) that are easily misdiagnosed as inguinal hernias.

METHODS

We retrospectively analyzed clinical materials of 41 consecutive cases of RLVs diagnosed by ultrasound in a single hospital from January 2011 to December 2015. Misdiagnosis rate, clinical and sonographic features, management after diagnosis and prognosis were recorded.

RESULTS

All forty-one cases were pregnant females in their second or third trimester. Twenty-eight cases were first misdiagnosed as inguinal hernias (68.3%). Thirty cases presented as reducible swelling in the inguinal area (73.2%), and twenty-five of which were painful (61.0%). Four cases only felt pain in the inguinal area without swelling (9.7%). Seven cases had no obvious discomfort (17.1%). All cases were diagnosed as RLVs by gray-scale and color Doppler ultrasonography and justified a wait-and-see strategy. Thirty-seven cases were followed until total recovery after delivery (follow-up rate 90.2%). Swelling with or without pain disappeared spontaneously postpartum.

CONCLUSIONS

RLVs are easily misdiagnosed as inguinal hernias and color Doppler of the inguinal area is the best examination for making the correct diagnosis. Conservative therapy for RLV is beneficial and safe when assured by color Doppler.

Molecular and structural changes related to hepatitis E virus antigen and its expression in testis inducing apoptosis in Mongolian gerbil model

Hepatitis E virus (HEV) infection has been associated with a wide range of extrahepatic manifestations, so this study was designed to examine the effect and role of HEV on structural and molecular changes in the testicular tissues of Mongolian gerbils experimentally infected with swine HEV. HEV RNA was first detected in testis at 14 days post-inoculation and reached a peak between 28 and 42 days later with viral load between 3.12 and 6.23 logs/g by PCR assays. Changes including vacuolation, sloughing of germ cells, formation of multinuclear giant cells, degeneration, necrosis of tubules and damaged blood-testis barrier were observed through transmission electron microscopy. HEV ORF2 antigen was detected in the sperm cell cytoplasm along with decrease in relative protein of zonula occludens-1 through immunohistochemistry. HEV ORF3 antigen and ZO-1 protein were detectable by Western blotting. Lower (P<.05) serum testosterone and higher (P<.05) blood urea nitrogen level was observed in inoculated Mongolian gerbils. Likewise, increased (P<.05) germ cell apoptosis rate was detected with significant increased expression of Fas-L and Fas in HEV-inoculated groups at each time points. Up-regulation (P<.05 or P<.01) in mRNA level of Fas-L, Fas, Bax, Bcl-2 and caspase-3 was observed in HEV RNA-positive testes. Our study demonstrated that after experimental inoculation, HEV can be detected in testis tissues and viral proteins produce structural and molecular changes that in turn disrupt the blood-testis barrier and induce germ cell apoptosis.

Evidence of Hepatitis E virus breaking through the blood-brain barrier and replicating in the central nervous system

Neurologic dysfunctions such as Guillain-Barre' syndrome, encephalitis, meningitis and transverse myelitis occur frequently in patients with hepatitis E virus (HEV) infection, and this study was conducted to better characterize the role of HEV in the pathogenesis of neurologic disorders. Genotype 4 strain of swine HEV was used to inoculate Mongolian gerbils. Reverse transcription-nested polymerase chain reaction (RT-nPCR), ELISA, histopathology, ultrastructural pathology and enzyme immunohistochemistry method were conducted to investigate the replication and localization of HEV in the central nervous system (CNS) and the consequent pathological changes. Both positive- and negative-strand HEV RNA was detectable in brain and spinal cord from 7 to 28 dpi (days postinoculation) via RT-nPCR. Various pathological changes such as perineural invasion, neuron necrosis, microglia nodule, lymphocyte infiltration, perivascular cuff and myelin degeneration were observed in HEV-positive brains and spinal cords. Immunohistochemical (IHC) staining targeting on HEV ORF2 protein revealed positive signals concentrated mainly in the cytoplasm of neuron, ependymal epithelium and choroid plexus area. Positive area density of ZO-1 (zonula occludens-1) in brain of HEV-positive gerbils decreased, while the GFAP (glial fibrillary acidic protein) expression was upregulated compared with control groups. These results provide strong evidence that HEV is able to damage the blood-brain barrier (BBB), replicate in brain and spinal cord, and hammer the causative role of HEV in the pathogenesis of neurologic disorders.

Experimental Investigation on Curing Stress in Polymer Composite Using Digital Gradient Sensing Technique

The curing stress and deformation of epoxy resin and aramid fiber/epoxy composites was measured using Digital Gradient Sensing (DGS) technique. First, the working principle of the DGS method was explained, and the governing equations were derived based on angular deflections of light rays. Then the angle deflection of light rays due to curing stress of epoxy resin was measured, and the effect of the fiber bundle and aramid fiber fabric on the stress distribution during formation was analyzed. The experimental results show that angular deflections of light rays can be related to nonuniform distribution of curing stress in epoxy. The fiber bundles and fabric style have important effects on the curing stress distribution. These results play an important role for predicting curing stress and deformation of fiber reinforced composites.

Vibrations of thin plates with small clamped patches

Eigenvalues of fourth-order elliptic operators feature prominently in stability analysis of elastic structures. This paper considers out-of-plane modes of vibration of a thin elastic plate perforated by a collection of small clamped patches. As the radius of each patch shrinks to zero, a point constraint eigenvalue problem is derived in which each patch is replaced by a homogeneous Dirichlet condition at its centre. The limiting problem is consequently not the eigenvalue problem with no patches, but a new type of spectral problem. The discrepancy between the eigenvalues of the patch-free and point constraint problems is calculated. The dependence of the point constraint eigenvalues on the location(s) of clamping is studied numerically using techniques from numerical algebraic geometry. The vibrational frequencies are found to depend very sensitively on the number and centre(s) of the clamped patches. For a range of number of punctures, we find spatial clamping patterns that correspond to local maxima of the base vibrational frequency of the plate.

Postharvest Strategies for Managing Phytophthora Brown Rot of Citrus using Potassium Phosphite in Combination with Heat Treatments

Phytophthora brown rot, caused by several species of Phytophthora, is an economically important disease of citrus in areas with rainfall during the late stages of fruit development. Recent export restrictions of California orange fruit to China due to the presence of brown rot caused by the quarantine pathogen Phytophthora syringae have mandated more rigorous disease management. We evaluated postharvest applications with the phosphonate fungicide potassium phosphite in combination with heat treatments. In timing studies, potassium phosphite at 1,500 μg/ml was most effective when applied within 18 h after inoculation of orange fruit with P. citrophthora, reducing the incidence of decay by >96% as compared with the control. Potassium phosphite was also highly effective in inoculations with P. syringae. Heated water treatments at 60°C were consistently and highly effective in reducing the incidence of brown rot after inoculation with P. citrophthora, whereas treatments at 55 or 50°C were more variable and generally less effective. Two-stage treatments of fruit were conducted in the laboratory to simulate current packinghouse practices and to evaluate any interaction of the efficacy of potassium phosphite with treatments of two commonly used postharvest fungicides (i.e., imazalil and thiabendazole [TBZ]) or a postharvest carnauba-based fruit coating. In these studies, an aqueous imazalil-potassium phosphite (2,000 μg/ml) dip at ambient temperature that was followed by a spray treatment of imazalil and TBZ prepared in fruit coating significantly reduced the incidence of brown rot from the control. When the aqueous dip was applied at 54°C, brown rot developed in only 1% of the fruit as compared with 76% in the water control. The efficacy of potassium phosphite was also demonstrated in commercial packinghouse treatments. Based on our research, this fungicide was registered for postharvest use against brown rot of citrus and is exempt from tolerance in the United States and many other countries.

Aerobic Stability and Effects of Yeasts during Deterioration of Non-fermented and Fermented Total Mixed Ration with Different Moisture Levels

The present experiment evaluated the influence of moisture level and anaerobic fermentation on aerobic stability of total mixed ration (TMR). The dynamic changes in chemical composition and microbial population that occur after air exposure were examined, and the species of yeast associated with the deterioration process were also identified in both non-fermented and fermented TMR to deepen the understanding of aerobic deterioration. The moisture levels of TMR in this experiment were adjusted to 400 g/kg (low moisture level, LML), 450 g/kg (medium moisture level, MML), and 500 g/kg (high moisture level, HML), and both non-fermented and 56-d-fermented TMR were subjected to air exposure to determine aerobic stability. Aerobic deterioration resulted in high losses of nutritional components and largely reduced dry matter digestibility. Non-fermented TMR deteriorated during 48 h of air exposure and the HML treatment was more aerobically unstable. On dry matter (DM) basis, yeast populations significantly increased from 10(7) to 10(10) cfu/g during air exposure, and Candida ethanolica was the predominant species during deterioration in non-fermented TMR. Fermented TMR exhibited considerable resistance to aerobic deterioration. Spoilage was only observed in the HML treatment and its yeast population increased dramatically to 10(9) cfu/g DM when air exposure progressed to 30 d. Zygosaccharomyces bailii was the sole yeast species isolated when spoilage occurred. These results confirmed that non-fermented and fermented TMR with a HML are more prone to spoilage, and fermented TMR has considerable resistance to aerobic deterioration. Yeasts can trigger aerobic deterioration in both non-fermented and fermented TMR. C. ethanolica may be involved in the spoilage of non-fermented TMR and the vigorous growth of Z. bailii can initiate aerobic deterioration in fermented TMR.

Serological surveillance for Penicillium marneffei infection in HIV-infected patients during 2004-2011 in Guangzhou, China

Prevalence of disseminated Penicillium marneffei infection is not known in human immunodeficiency virus (HIV)-infected patients. This retrospective study aimed to evaluate the prevalence of and risk factors for disseminated P. marneffei infection in HIV-infected patients during 2004-11 in Guangzhou, China. We tested 8131 archived HIV-infected patient serum samples for P. marneffei-specific mannoprotein (Mp1p) antigen using a highly sensitive and specific ELISA that we previously established. The CD4 count of 2686 cases was determined by flow cytometry. Logistic regression was used to assess predictors of Mp1p antigenaemia. The overall prevalence of disseminated penicilliosis as detected by positive serum Mp1p antigen was 9.36% (761/8131), in good concordance with Platelia™ Aspergillus immunoassay. During 2004-11, the prevalence increased to a peak of 12.58% (158/1256) in 2010 and decreased in 2011. Penicilliosis was strongly associated with progression from HIV to AIDS (OR 4.66, 95% CI 3.94-5.51, p <0.001) and humidity (OR 1.02, 95% CI 1.01-1.03, p 0.002). Disseminated penicilliosis occurred mainly during the rainy seasons (p <0.001). For 2686 cases with known CD4 count, logistic regression showed that CD4 count of <200 cells/μL was a risk factor for penicilliosis (OR 2.90, 95% CI 1.10-7.66, p 0.032), especially when it was <50 cells/μL (OR 24.26, 95% CI 10.63-55.36, p <0.001) during which 28.06% of patients developed disseminated penicilliosis. In conclusion, approximately 9.36% of the HIV-infected patients in our study developed disseminated penicilliosis. Rapid diagnosis may be achieved by performing serological surveillance for Mp1p antigenaemia as a routine procedure for all HIV-infected patients with CD4 count of <50 cells/μL.

mGluR3 promotes proliferation of human embryonic cortical neural progenitor cells by activating ERK1/2 and JNK2 signaling pathway in vitro

Metabotropic glutamate receptors (mGluRs) regulate the proliferation and differentiation of neural progenitor cells (NPCs) in brain; however, the mechanisms remain unknown. In this study, we investigated the effect of mGluR3 on the proliferation of human embryonic neural progenitor cells (NPCs), the expression of cyclin D1 and the activation of signaling pathways of mitogen-activated protein kinases (MAPKs). The results showed that mGluR3 agonist N-Acetylaspartylglutamate (NAAG) increased the proliferation of NPCs by increasing cell activity, diameter of neurospheres and cell division. In addition, mGluR3 siRNA decreased the NPC proliferation. The protein expressions of cyclin D1 increased with NAAG treatment and decreased after siRNA treatment. It was also found that activation of extracellular signal-regulated protein kinase (ERK) and c-Jun N-terminal protein kinase (JNK) signaling pathways were involved in the proliferation of NPCs. NAAG increased phosphorylation of ERK1/2 and JNK2 levels, and meanwhile p-p38 level decreased; but p-ERK1/2 and p-JNK2 levels decreased after siRNA treatment, and p-p38 level increased. ERK1/2 inhibitor U0126 and JNK2 inhibitor SP600125 attenuated the increase of proliferation induced by NAAG. These findings demonstrated that mGluR3 promoted the proliferation of human embryonic cortical NPCs and increased cyclin D1 expression by activating ERK1/2 and JNK2 signaling pathways in vitro, suggesting that mGluR3 may be a target molecule for regulating NPC proliferation in brain development.

Inter-observer and intra-observer variability in the diagnosis of dysplasia in patients with inflammatory bowel disease: correlation of pathological and endoscopic findings

AIM

Colonic epithelial dysplasia is deemed the precursor lesion of cancer arising in inflammatory bowel disease (IBD). It has been suggested that many dysplastic lesions could be endoscopically detected to obtain target biopsies, leading to better yield. However, the clinical impact of a diagnosis of dysplasia may be hampered by a significant degree of histological and endoscopic intra-observer and inter-observer variability. This study aimed to evaluate intra-observer and inter-observer variability in the microscopic diagnosis of dysplasia in IBD and correlate endoscopic and histological findings.

METHOD

In total, 158 cases of ulcerative colitis and 14 of Crohn's disease with dysplasia were selected from a pathology database. Slides were blindly reviewed twice by two expert gastrointestinal pathologists. Results of endoscopic examinations were extracted from the reports. The degree of intra-observer and inter-observer variability was determined by kappa statistics.

RESULTS

Overall, there was an excellent degree of histopathological inter-observer agreement (κ = 0.786). The lowest level of agreement in the dysplasia group was for indefinite dysplasia (κ = 0.251). Negative and high grade dysplasia diagnosis reached the highest level of agreement with κ values of 0.822 [95% confidence interval (CI) 0.673-0.971] and 1.00 (95% CI 0.850-1.149), respectively. Intra-observer agreement was good and increased during the latter period of the study (κ = 0.734, 95% CI 0.642-0.826). Endoscopic-histological correlation was poor among the negative endoscopies, as up to 43% of cases were diagnosed with at least focal high grade dysplasia. The endoscopic-histological correlation improved when evaluating suspicious endoscopic lesions.

CONCLUSION

Dysplasia is reliably diagnosed by expert gastrointestinal pathologists but has poor correlation with an endoscopic diagnosis of dysplasia.

Understanding Cr segregation at the He bubble surface in Fe

Although Cr segregation at the free Fe surface is weak, noticeable segregation of Cr at the He bubble surface in Fe has recently been observed. To understand the driving force for Cr segregation, we have carried out first-principles density functional theory calculations on the energetics of solute Cr atoms at the He bubble surface, which was modeled by a Fe/He interface. We find that both the compressive stress produced by the He bubble and the direct interfacial interaction promote Cr segregation from inside the bulk to the bubble surface, along with reduced spin polarization. Electronic structure analyses show that at the Fe/He interface, Cr is more compressible than Fe due to having more empty e(g) orbitals and, accordingly, the Fe surface gets energetically more favorable for Cr than in the bulk. On the other hand, the segregation of Cr increases the charge density at the bubble surface, and thus hinders assimilation of further He atoms.

Human exposure from dioxins in soil

Dioxins are a family of chemical compounds that has received considerable attention, both historically and currently. This article reviews scientific field studies that examine the relationship between living on soil contaminated with dioxins and the level of dioxins in people's serum, with an emphasis on the University of Michigan Dioxin Exposure Study (UMDES), the largest and most comprehensive study of its kind. These studies conclude that the levels of dioxins in serum are most strongly correlated with age, gender, body mass index, weight loss, breast feeding, and smoking. Levels of dioxins in soil are not significant predictors for dioxin concentrations in serum. The increase in serum dioxin levels that is seen with age results from historic exposure and does not represent ongoing exposure. Based on the scientific field studies conducted to date, it appears that, in the absence of the consumption of contaminated animal products, there is little evidence of ongoing exposure from contaminated soil.

Effect of alloying additions on the hydrogen-induced grain boundary embrittlement in iron

Using ab initio density functional theory calculations, we have investigated the influence of Mo, V and Pd on the H-induced grain boundary embrittlement in Fe. We find that, in the high impurity concentration systems, all of the three alloying elements facilitate H embrittlement at the Σ3 (111) [Formula: see text] grain boundary in Fe. The calculated binary effects of the H-X (X = Mo, V, Pd) couples are 0.063, 0.074 and 0.040 eV, respectively. On the other hand, in the large unit cell with low impurity concentration, both Mo and V can facilitate H embrittlement, and the binary effects of pairs are 0.152 and 0.164 eV, respectively. While Pd reduces the H embrittlement on the cohesion of the Fe grain boundary with the binary effect of - 0.1 eV. The H-X (X = Mo, V, Pd) interactions are interpreted by electronic structure analyses.

Foliar Blight of Annual Vinca (Catharanthus roseus) Caused by Phytophthora tropicalis in Virginia

Annual vinca (Catharanthus roseus), also known as Madagascar periwinkle, has been cultivated as a major color crop for landscape and as an herbal medicine. This plant performs well in dry, warm locations with full sun or partial shade. Two-month-old diseased plants (cv. First Kiss Blueberry) with blighted leaves and stems were received from a local nursery in Suffolk, VA in May 2009. The disease began with dark, greenish black lesions on young leaves. Lesions gradually became tan or brown and leaves wilted and curled and finally turned necrotic. Brown, sunken lesions beginning at the branching points were typical symptoms on blighted stems and shoots. Blighted areas and spots were approximately 30 to 90 mm long and 20 to 40 mm wide on leaves and 40 mm long on stems. A Phytophthora species previously unknown to attack this plant was consistently isolated from diseased leaves and stems, and resultant isolates were grown on PARP-V8 agar. These isolates produced papillate sporangia on umbellate sympodium. Sporangia were mostly ellipsoid with a length/breadth ratio of >1.8 and tapered base; they were caducous with a long pedicel (usually >50 μm). These isolates also produced chlamydospores that averaged 31 μm in diameter. The isolates were identified as Phytophthora tropicalis by morphology. The identity was confirmed by DNA fingerprinting (1) and sequence analysis of ribosomal DNA internal transcribed spacers (GenBank Accession No. GQ478707). For pathogenicity studies, a zoospore suspension of 1,100 spores per milliliter was sprayed onto the foliage of 50-day-old healthy plants of the same cultivar grown in pine bark medium in six 10-cm-diameter plastic containers with a hand mister in the evening until runoff. Control plants were sprayed with tap water. Plants were placed in a tray containing a small amount of water and enclosed in plastic tents overnight to facilitate infection. The tents were removed the following morning, and plants were kept in a greenhouse under natural light and watered as needed. Within 4 days, all six inoculated plants developed foliar symptoms similar to what was observed on the diseased plant samples from the production nursery. The pathogen was reisolated from infected leaves and stems and its identity was confirmed by colony PCR-single-strand conformation polymorphism (3). The pathogenicity test was repeated once with the same results. Phytophthora aerial blight is a common destructive disease of annual vinca, which is usually caused by P. nicotianae. To our knowledge, this is the first report of foliar blight caused by P. tropicalis on annual vinca in Virginia. According to the head grower who submitted the disease samples, this new disease caused 10% crop loss of annual vinca this past spring. P. tropicalis was previously reported to attack ornamental shrubs, including Pieris japonica and Rhododendron catawbiense (2). This study indicates that P. tropicalis could be a potential threat to herbaceous annual crops as well. References: (1) M. E. Gallegly and C. X. Hong. Phytophthora: Identifying Species by Morphology and DNA Fingerprints. The American Phytopathological Society, St. Paul, MN, 2008. (2) C. Hong et al. Plant Dis. 90:525, 2006. (3) P. Kong et al. J. Microbiol. Methods 61:25, 2005.