Epidemiological Investigation of Yak (Bos grunniens) Fascioliasis in the Pastoral Area of Qinghai-Tibet Plateau, China

The objective of this investigation was to understand the epidemiology of fascioliasis in yaks in the alpine pastoral areas of the Qinghai-Tibet Plateau, China. The prevalence of Fasciola hepatica infection was estimated by examining eggs in the feces of yaks and by autopsy after the slaughter. Yaks were sampled from a total of 16 representative counties in Qinghai province, and risk factors were assessed based on regional and age characteristics. Fecal samples were obtained from 1542 yaks aged 0-1 (<1 year old), 1-2 (≥1 year old and <3 years old), and over 3 years (≥3 years old). In addition, 242 yaks over 3 years old who had not undergone fecal examinations were randomly selected for autopsy. A total of 267 fecal samples were positive for Fasciola spp. eggs. The average infection rate was 17.32% (0-60.61%), and the average infection intensity was 51.9 eggs per gram (epg) of feces, with intensities ranging from 18 to 112 epg. In Maduo, Dari, Zhiduo, Chengduo, and Datong counties, the Fasciola spp. eggs infection rate was zero. Fasciola spp. adult flukes were detected in 66 out of 242 yaks at autopsy, with a total infection rate of 27.27% and an average infection intensity of 21.2 (adult worms), with intensities ranging from 3 to 46 worms. Logistic regression model analysis showed that age was a significant risk factor for yak infection with Fasciola spp. In addition, the risk varied between regions: Haiyan, Gangcha, Duran, and Wulan were all high-risk areas for yak infection with Fasciola spp. The spatial distribution of the Fasciola spp. infection rate in each region showed a very weak negative correlation (Moran's I = -0.062), Duran formed a spatial distribution of high-low clusters with surrounding areas, and Datong formed a low-high clustering distribution characteristic with the surrounding areas. This investigation revealed that the infection rate of Fasciola spp. in yaks was higher on the Qinghai-Tibet Plateau. Increasing age was a risk factor for infection with Fasciola spp.; different regions also have a different risk of Fasciola spp. infection. Only two regions showed clustering characteristics in the spatial distribution of infection rates. These findings extend the epidemiological information on Fasciola spp. infection in yaks and provide baseline data for the execution of control measures against Fasciola spp. infection.

Dynamic nomogram for long-term survival in patients with locally advanced oropharyngeal cancer after (chemo)radiotherapy

PURPOSE

This study aimed to establish a nomogram for predicting overall survival (OS) in oropharyngeal cancer patients treated with curative (chemo)radiotherapy.

MATERIALS AND METHODS

The dynamic nomogram was constructed on 273 patients with oropharyngeal squamous cell carcinoma treated in a Tertiary Head and Neck Cancer Unit. The clinical features that were previously reported to be associated with OS were analyzed. The performance of the nomogram was assessed using concordance index (C-index) and calibration curves.

RESULTS

The nomogram incorporated three explanatory variables derived from a decision tree approach including HPV status, N classification according to 8th edition TNM and early response to (chemo)radiotherapy. The nomogram was capable to predict OS with a validation C-index of 0.768. The proposed stratification in risk groups allowed significant distinction between Kaplan-Meier curves for OS outcome (p < 0.0001).

CONCLUSIONS

The nomogram provided an accurate evaluation of OS for oropharyngeal cancer patients treated with curative (chemo)radiotherapy.

The Impact of Interactive MRI-Based Radiologist Review on Radiotherapy Target Volume Delineation in Head and Neck Cancer

BACKGROUND AND PURPOSE

Peer review of head and neck cancer radiation therapy target volumes by radiologists was introduced in our center to optimize target volume delineation. Our aim was to assess the impact of MR imaging-based radiologist peer review of head and neck radiation therapy gross tumor and nodal volumes, through qualitative and quantitative analysis.

MATERIALS AND METHODS

Cases undergoing radical radiation therapy with a coregistered MR imaging, between April 2019 and March 2020, were reviewed. The frequency and nature of volume changes were documented, with major changes classified as per the guidance of The Royal College of Radiologists. Volumetric alignment was assessed using the Dice similarity coefficient, Jaccard index, and Hausdorff distance.

RESULTS

Fifty cases were reviewed between April 2019 and March 2020. The median age was 59 years (range, 29-83 years), and 72% were men. Seventy-six percent of gross tumor volumes and 41.5% of gross nodal volumes were altered, with 54.8% of gross tumor volume and 66.6% of gross nodal volume alterations classified as "major." Undercontouring of soft-tissue involvement and unidentified lymph nodes were predominant reasons for change. Radiologist review significantly altered the size of both the gross tumor volume (P  = .034) and clinical target tumor volume (P  = .003), but not gross nodal volume or clinical target nodal volume. The median conformity and surface distance metrics were the following: gross tumor volume Dice similarity coefficient = 0.93 (range, 0.82-0.96), Jaccard index = 0.87 (range, 0.7-0.94), Hausdorff distance = 7.45 mm (range, 5.6-11.7 mm); and gross nodular tumor volume Dice similarity coefficient = 0.95 (0.91-0.97), Jaccard index = 0.91 (0.83-0.95), and Hausdorff distance = 20.7 mm (range, 12.6-41.6). Conformity improved on gross tumor volume-to-clinical target tumor volume expansion (Dice similarity coefficient = 0.93 versus 0.95, P  = .003).

CONCLUSIONS

MR imaging-based radiologist review resulted in major changes to most radiotherapy target volumes and significant changes in volume size of both gross tumor volume and clinical target tumor volume, suggesting that this is a fundamental step in the radiotherapy workflow of patients with head and neck cancer.

Hair Zinc and Chromium Levels Were Associated with a Reduced Likelihood of Age Related Cognitive Decline in Centenarians and Oldest-Old Adults

BACKGROUND

Cognitive function has inevitable decline with advancing age in nature, and age-related cognitive decline (ARCD) is of increasing concern to aging population. Scarce study has involved the associations between hair trace elements and ARCD in older adults, especially in centenarians and oldest-old adults. This study was to investigate the associations between hair trace elements and ARCD in centenarians and oldest-old adults.

METHODS

Based on the household registration information of centenarians and oldest-old adults provided by the Civil Affairs Department of Hainan Province, China, the investigators conducted a one-to-one household survey among centenarians (≥100 years old) and oldest-old adults (80-99 years old). All 50 centenarians had a median age of 103 years and females accounted for 68.0%. All 73 oldest-old adults aged 80-99 years had a median age of 90 years and females accounted for 82.2%. Basic information were obtained with questionnaire interview, physical examination, biological test and hair collection by pre-trained local doctors and nurses. An inductively coupled plasma mass spectrometer was used to measure hair trace elements. All data in this study comes from China. Age, sex, body mass index, systolic blood pressure, diastolic blood pressure, smoking, drinking, hemoglobin, albumin, fasting blood pressure, zinc, chromium, copper, selenium, iron, manganese, strontium, lead, magnesium, potassium, and barium were simultaneously included in multivariate Logistic regression analysis. One adjusted model was done with all hair trace elements together.

RESULTS

Zinc and chromium levels were significantly lower in participants with ARCD than those without ARCD (P < 0.05 for all). Multivariate Logistic regression analysis indicated that zinc [odds ratio (OR): 0.988, 95%confidence interval (95%CI): 0.977-0.999] and chromium (OR: 0.051, 95%CI: 0.004-0.705) were associated with a reduced likelihood of ARCD (P < 0.05 for all).

CONCLUSIONS

Hair zinc and chromium levels were associated with a reduced likelihood of ARCD in centenarians and oldest-old adults. Further studies are necessary to verify if zinc and chromium supplementation has the potential to improve cognitive function and prevent ARCD development.

Effects of weight loss on bone turnover, inflammatory cytokines, and adipokines in Chinese overweight and obese adults

PURPOSE

Plenty of studies have examined the long term effect of weight loss on bone mineral density. This study aimed to explore the effects of 10% weight loss on early changes in bone metabolism as well as the possible influencing factors.

METHODS

Overweight and obese outpatients (BMI > 24.0 kg/m²) were recruited from the nutrition clinic and followed a calorie-restricted, high-protein, low-carbohydrate diet program. Dietary intake, body composition, serum procollagen type I N-propeptide (PINP), β-Crosslaps, PTH, 25(OH) VitD, a series of inflammatory cytokines and adipokines were measured for the participants before starting to lose weight and after 10% weight loss (NCT04207879).

RESULTS

A total of 75 participants were enrolled and 37 participants achieved a weight loss of at least 10%. It was found that PINP decreased (p = 0.000) and the β-Crosslaps increased (p = 0.035) in female participants. Decreases in PTH (p = 0.001), serum IL-2 (p = 0.013), leptin (p = 0.001) and increases in 25(OH) VitD (p = 0.001), serum ghrelin (p = 0.033) were found in 37 participants after 10% of their weight had been lost. Change in PINP was detected to be significantly associated with change in lean body mass (r = 0.418, p = 0.012) and change in serum ghrelin(r = - 0.374, p = 0.023).

CONCLUSIONS

Bone formation was suppressed and bone absorption was increased in female subjects after a 10% weight loss. Bone turnover was found to be associated with lean body mass and affected by the circulating ghrelin level.

The ability of post-chemoradiotherapy DWI ADCmean and 18F-FDG SUVmax to predict treatment outcomes in head and neck cancer: impact of human papilloma virus oropharyngeal cancer status

OBJECTIVES

To evaluate the ability of post-chemo-radiotherapy (CRT) diffusion-weighted-MRI apparent diffusion coefficient (ADCmean) and 18F-FDG PET maximum standardized uptake value (SUVmax) to predict disease-free survival (DFS) in head and neck squamous cell carcinoma (HNSCC), and to determine whether this ability is influenced by human papillomavirus oropharyngeal cancer (HPV-OPC) status.

METHODS

This prospective cohort observational study included 65 participants (53 male, mean ± SD age 59.9 ± 7.9 years, 46 HPV-OPC) with stage III or IV HNSCC. Primary tumour and nodal ADCmean (pre-treatment, 6- and 12-weeks post-CRT) and SUVmax (12-weeks post-CRT) were measured. Variables were compared with 2-year DFS (independent t-test/Mann-Whitney test) and overall DFS (Cox regression), before and after accounting for HPV-OPC status. Variables were also compared between HPV-OPC and other HNSCC subgroups after stratifying for DFS.

RESULTS

Absolute post-CRT ADCmean values predicted 2-year DFS and overall DFS for all participants (p = 0.03/0.03, 6-week node; p = 0.02/0.03 12-week primary tumour) but not in the HPV-OPC subgroup. In participants with DFS, percentage interval changes in primary tumour ADCmean at 6- and 12-weeks were higher in HPV-OPC than other HNSCC (p = 0.01, 6 weeks; p = 0.005, 12 weeks). The 12-week post-CRT SUVmax did not predict DFS.

CONCLUSION

Absolute post-CRT ADCmean values predicted DFS in HNSCC but not in the HPV-OPC subgroup. Amongst participants with DFS, post-CRT percentage interval changes in primary tumour ADCmean were significantly higher in HPV-OPC than in other HNSCC. Knowledge of HPV-OPC status is crucial to the clinical utilisation of post-CRT DWI-MRI for the prediction of outcomes.

18F-FDG-PET in guided dose-painting with intensity modulated radiotherapy in oropharyngeal tumours: A phase I study (FiGaRO)

BACKGROUND AND PURPOSE

The FiGaRO trial assessed the feasibility and safety of using an FDG-PET-based dose-painting technique to deliver a radiotherapy (RT) boostto the FDG-avid primary tumour in patients with locally advanced high and intermediate risk oropharyngeal cancer.

MATERIALS AND METHOD

Patients underwent a planning 18FDG-PET-CT scan, immobilised in the treatment position, after one cycle of induction chemotherapy. The volume of persistent FDG-avidity in the primary tumour was escalated to 71.5 Gy in30 fractions delivered using a simultaneous integrated boost Intensity Modulated RT (SIB-IMRT) technique. RT was delivered with concomitant Cisplatin following 2 cycles of induction chemotherapy. The primary outcome was the incidence of grade ≥ 3 late mucosal toxicity 12 months post-treatment, with an excess rate of >10% regarded as unacceptable.

RESULTS

Twenty-nine patients were included and twenty-four were treated between 2014 and 2018, in two UK centres. Median follow-up was 36 months (range 4-56 months). Pre-defined planning target volume objectives and organ at risk dose constraints were met in all cases. There were no incidents of acute grade 4 toxicity. There were 4 cases of grade ≥ 3 mucosal toxicity at 12 months post-treatment (19.1%). There were no cases of persistent mucosal ulceration at 12 months. Overall survival at 3-years was 87.5%, 92.9% for intermediate and 70.0% for high risk patients.

CONCLUSION

Late toxicity rates, although higher than anticipated, are comparable to contemporary published data for standard dose chemo-IMRT. Results suggest improved 3y survival rates for high risk patients. This approach merits further investigation. ClinicalTrials.gov Identifier: NCT02953197.

Reporter system architecture affects measurements of noncanonical amino acid incorporation efficiency and fidelity

The ability to genetically encode noncanonical amino acids (ncAAs) within proteins supports a growing number of applications ranging from fundamental biological studies to enhancing the properties of biological therapeutics. Currently, our quantitative understanding of ncAA incorporation systems is confounded by the diverse set of characterization and analysis approaches used to quantify ncAA incorporation events. While several effective reporter systems support such measurements, it is not clear how quantitative results from different reporters relate to one another, or which details influence measurements most strongly. Here, we evaluate the quantitative performance of single-fluorescent protein reporters, dual-fluorescent protein reporters, and cell surface-displayed protein reporters of ncAA insertion in response to the TAG (amber) codon in yeast. While different reporters support varying levels of apparent readthrough efficiencies, flow cytometry-based evaluations with dual reporters yielded measurements exhibiting consistent quantitative trends and precision across all evaluated conditions. Further investigations of dual-fluorescent protein reporter architecture revealed that quantitative outputs are influenced by stop codon location and N- and C-terminal fluorescent protein identity. Both dual-fluorescent protein reporters and a "drop-in" version of yeast display support quantification of ncAA incorporation in several single-gene knockout strains, revealing strains that enhance ncAA incorporation efficiency without compromising fidelity. Our studies reveal critical details regarding reporter system performance in yeast and how to effectively deploy such reporters. These findings have substantial implications for how to engineer ncAA incorporation systems-and protein translation apparatuses-to better accommodate alternative genetic codes for expanding the chemical diversity of biosynthesized proteins.

Expert Consensus on the Management of Adverse Events During Treatment with Lenvatinib for Thyroid Cancer

AIMS

Lenvatinib is an oral multi-kinase inhibitor approved for the treatment of adults with progressive, locally advanced or metastatic, differentiated thyroid carcinoma refractory to radioactive iodine.

MATERIALS AND METHODS

A literature review was undertaken to inform the development of consensus-based guidance for the routine management of adverse events associated with lenvatinib. PubMed was searched on 24 October 2017; the search terms were 'lenvatinib' and 'thyroid cancer'.

RESULTS

Hypertension, diarrhoea, weight loss, skin toxicities and cardiovascular adverse events were considered. For grade 1/2 diarrhoea, initial treatment should be loperamide with a 1-week treatment interruption if diarrhoea persists and dose reduction if diarrhoea recurs on reinitiation of lenvatinib. Blood pressure should be monitored daily in patients with pre-existing hypertension, otherwise from 1 week after the initiation of lenvatinib and weekly for the first 2 months. For patients with systolic blood pressure ≥135 mmHg to <160 mmHg or diastolic blood pressure ≥85 mmHg to <100 mmHg, lenvatinib should be continued but antihypertensive therapy initiated/intensified. For patients who remain hypertensive, a treatment break can be considered with lenvatinib reinitiated at a reduced dose once the patient's blood pressure has stabilised for at least 48 h. Weight loss of 10% of baseline body weight or the onset of anorexia should be managed with a 1-week treatment break; patients should maintain a healthy, active lifestyle. For patients with grade 2 proteinuria, lenvatinib may be continued, but an angiotensin II receptor blocker or angiotensin converting enzyme inhibitor should be commenced. For grade >3 proteinuria, lenvatinib should be interrupted until proteinuria returns to 1+. For chronic proteinuria, lenvatinib should be stopped. Skin toxicities should be managed with moisturisers or emollients and soap substitutes.

CONCLUSIONS

Prophylaxis, regular monitoring and symptomatic management with appropriate short treatment breaks and, for persistent adverse events, dose reductions, are recommended to enable patients to remain on the optimal dose regimen.

Evaluation of common variants in the CNR2 gene and its interaction with abdominal obesity for osteoporosis susceptibility in Chinese post-menopausal females

Objectives

The objective of this study was to investigate the association of four single-nucleotide polymorphisms (SNPs) of the cannabinoid receptor 2 (CNR2) gene, gene-obesity interaction, and haplotype combination with osteoporosis (OP) susceptibility.

Methods

Chinese patients with OP were recruited between March 2011 and December 2015 from our hospital. In this study, a total of 1267 post-menopausal female patients (631 OP patients and 636 control patients) were selected. The mean age of all subjects was 69.2 years (sd 15.8). A generalized multifactor dimensionality reduction (GMDR) model and logistic regression model were used to examine the interaction between SNP and obesity on OP. For OP patient-control haplotype analyses, the SHEsis online haplotype analysis software (http://analysis.bio-x.cn/) was employed.

Results

The logistic regression model revealed that the C allele of rs2501431 and the G allele of rs3003336 were associated with increased OP risk, compared with those with wild genotype. However, no significant correlations were found when analyzing the association of rs4237 and rs2229579 with OP risk. The GMDR analysis suggested that the interaction model composed of two factors, rs3003336 and abdominal obesity (AO), was the best model with statistical significance (p-value from sign test (P_sign) = 0.012), indicating a potential gene-environment interaction between rs3003336 and AO. Overall, the two-locus models had a cross-validation consistency of 10/10 and had a testing accuracy of 0.641. Abdominally obese subjects with the AG or GG genotype have the highest OP risk, compared with subjects with the AA genotype and normal waist circumference (WC) (odds ratio (OR) 2.23, 95% confidence interval (CI) 1.54 to 3.51). Haplotype analysis also indicated that the haplotype containing the rs3003336-G and rs2501431-C alleles was associated with a statistically increased OP risk.

Conclusion

Our results suggested that the C allele of rs2501431 and the G allele of rs3003336 of the CNR2 gene, interaction between rs3003336 and AO, and the haplotype containing the rs3003336-G and rs2501431-C alleles were all associated with increased OP risk.

Cite this article: Bone Joint Res 2019;8:544–549.

A Protocol for Transverse Cardiac Slicing and Optical Mapping in Murine Heart

Thin living tissue slices have recently emerged as a new tissue model for cardiac electrophysiological research. Slices can be produced from human cardiac tissue, in addition to small and large mammalian hearts, representing a powerful in vitro model system for preclinical and translational heart research. In the present protocol, we describe a detailed mouse heart transverse slicing and optical imaging methodology. The use of this technology for high-throughput optical imaging allows study of electrophysiology of murine hearts in an organotypic pseudo two-dimensional model. The slices are cut at right angles to the long axis of the heart, permitting robust interrogation of transmembrane potential (Vm) and calcium transients (CaT) throughout the entire heart with exceptional regional precision. This approach enables the use of a series of slices prepared from the ventricles to measure Vm and CaT with high temporal and spatial resolution, allowing (i) comparison of successive slices which form a stack representing the original geometry of the heart; (ii) profiling of transmural and regional gradients in Vm and CaT in the ventricle; (iii) characterization of transmural and regional profiles of action potential and CaT alternans under stress (e.g., high frequency pacing or β-adrenergic stimulation) or pathological conditions (e.g., hypertrophy). Thus, the protocol described here provides a powerful platform for innovative research on electrical and calcium handling heterogeneity within the heart. It can be also combined with optogenetic technology to carry out optical stimulation; aiding studies of cellular Vm and CaT in a cell type specific manner.

Synthesis of high quality silver nanowires and their applications in ultrafast photonics

Silver nanowires are widely used in catalysts, surface enhanced Raman scattering, microelectronic equipment, thin film solar cells, microelectrodes and biosensors for their excellent conductivity, heat transfer, low surface resistance, high transparency and good biocompatibility. However, the optical nonlinearity of silver nanowires has not been further explored yet. In this paper, three silver nanowire samples with different concentrations are produced via a typical hydrothermal method. Their applications to fiber lasers are implemented to prove the optical nonlinearity of silver nanowires for the first time. Based on three kinds of silver nanowires, the mode-locked operation of fiber lasers is successfully realized. Moreover, the fiber laser based on the silver nanowire with a concentration of 2 mg/L demonstrates the shortest pulse duration of 149.3 fs. The experiment not only proves the optical nonlinearity of silver nanowires, but also has some enlightenment on the selection of the optimum concentration of silver nanowires in the consideration of ultrashort pulse output.

Nonlinear optical properties of MoS2-WS2 heterostructure in fiber lasers

As a saturable absorption material, the heterostructure with the van der Waals structure has been paid much attention in material science. In general, the heterogeneous combination is able to neutralize, or even exceed, the individual material's advantages in some aspects. In this paper, which describes the magnetron sputtering deposition method, the tapered fiber is coated by the MoS₂-WS₂ heterostructure, and the MoS₂-WS₂ heterostructure saturable absorber (SA) is fabricated. The modulation depth of the prepared MoS₂-WS₂ heterostructure SA is measured to be 19.12%. Besides, the theoretical calculations for the band gap and carrier mobility of the MoS₂-WS₂ heterostructure are provided. By employing the prepared SA, a stable and passively erbium-doped fiber laser is implemented. The generated pulse duration of 154 fs is certified to be the shortest among all fiber lasers based on transition mental dichalcogenides. Results in this paper provide the new direction for the fabrication of ultrafast photon modulation devices.

Palatine tonsil SUVmax on FDG PET-CT as a discriminator between benign and malignant tonsils in patients with and without head and neck squamous cell carcinoma of unknown primary

AIM

To analyse the maximum standardised uptake value (SUVmax) ratio between tonsils in patients with and without tonsillar carcinoma to determine useful diagnostic thresholds.

MATERIALS AND METHODS

Positron-emission tomography (PET)/computed tomography (CT) examinations of patients with suspected head and neck squamous cell carcinoma (SCC) and controls from April 2013 to September 2016 were reviewed retrospectively. Tonsillar SUVmax ratios (ipsilateral/contralateral for malignant tonsils, maximum/minimum for patients without [controls]) were calculated and used to construct a receiver operating characteristic (ROC) curve.

RESULTS

Twenty-five patients had tonsillar carcinoma (mean SUVmax ratio of 2, range 0.89-5.4) and 86 patients acted as controls (mean SUVmax ratio of 1.1, range 1-1.5). Using the ROC, the most accurate SUVmax ratio for identifying malignancy was >1.2 (77% sensitivity, 86% specificity). A potentially more clinically useful SUVmax ratio is ≥1.6 with 62% sensitivity and 100% specificity.

CONCLUSION

An SUVmax ratio between tonsils of ≥1.6 is highly suspicious for SCC and could be used to direct site of biopsy. Some malignant tonsils had normal FDG uptake; therefore, PET/CT should not be used to exclude tonsillar cancer. Minor asymmetrical uptake is frequently seen in non-malignant tonsils and does not necessarily require further investigation. Due to the single centre nature of this study and the recognised variation in SUV measurements between PET scans, other centres may need to develop their own cut-offs.

Association of interleukin 22 gene polymorphisms and serum IL-22 level with risk of systemic lupus erythematosus in a Chinese population

The aim of this study was to investigate the association between the single-nucleotide polymorphisms (SNPs) of the interleukin 22 (IL-22) gene and systemic lupus erythematosus (SLE) in a Chinese population. Three IL-22 SNPs (rs2227485, rs2227513 and rs2227491) were genotyped using SNaPshot SNP genotyping assays and identified by sequencing in 314 SLE patients and 411 healthy controls. The IL-22 level of serum was assessed by enzyme-linked immunosorbent assay (ELISA) kits. Data were analysed by spss version 17.0 software. We found that rs2227513 was associated with an increased risk of SLE [AG versus AA: adjusted odds ratio (aOR) = 2·24, 95% confidence interval (CI) = 1·22-4·12, P = 0·010; G versus· A: adjusted OR = 2·18, 95% CI = 1·20-3·97, P = 0·011]. Further analysis in patients with SLE showed that the AG genotype and G allele were associated with an increased risk of renal disorder in SLE (G versus A: aOR = 3·09, 95% CI = 1·30-7·33, P = 0·011; AG versus· AA: aOR = 3·25, 95% CI = 1·35-7·85, P = 0·009). In addition, the concentration of IL-22 was significantly lower in the rs2227513 AG genotype compared with AA genotype (P = 0·028). These results suggest that rs2227513 polymorphism might contribute to SLE susceptibility, probably by decreasing the expression of IL-22.

Transverse cardiac slicing and optical imaging for analysis of transmural gradients in membrane potential and Ca2+ transients in murine heart

Key points

A robust cardiac slicing approach was developed for optical mapping of transmural gradients in transmembrane potential (V_m) and intracellular Ca²⁺ transient (CaT) of murine heart.

Significant transmural gradients in V_m and CaT were observed in the left ventricle.

Frequency‐dependent action potentials and CaT alternans were observed in all ventricular regions with rapid pacing, with significantly greater incidence in the endocardium than epicardium.

The observations demonstrate the feasibility of our new approach to cardiac slicing for systematic analysis of intrinsic transmural and regional gradients in V_m and CaT.

Abstract

Transmural and regional gradients in membrane potential and Ca²⁺ transient in the murine heart are largely unexplored. Here, we developed and validated a robust approach which combines transverse ultra‐thin cardiac slices and high resolution optical mapping to enable systematic analysis of transmural and regional gradients in transmembrane potential (V_m) and intracellular Ca²⁺ transient (CaT) across the entire murine ventricles. The voltage dye RH237 or Ca²⁺ dye Rhod‐2 AM were loaded through the coronary circulation using a Langendorff perfusion system. Short‐axis slices (300 μm thick) were prepared from the entire ventricles (from the apex to the base) by using a high‐precision vibratome. Action potentials (APs) and CaTs were recorded with optical mapping during steady‐state baseline and rapid pacing. Significant transmural gradients in V_m and CaT were observed in the left ventricle, with longer AP duration (APD₅₀ and APD₇₅) and CaT duration (CaTD₅₀ and CaTD₇₅) in the endocardium compared with that in the epicardium. No significant regional gradients were observed along the apico‐basal axis of the left ventricle. Interventricular gradients were detected with significantly shorter APD₅₀, APD₇₅ and CaTD₅₀ in the right ventricle compared with left ventricle and ventricular septum. During rapid pacing, AP and CaT alternans were observed in most ventricular regions, with significantly greater incidence in the endocardium in comparison with epicardium. In conclusion, these observations demonstrate the feasibility of our new approach to cardiac slicing for systematic analysis of intrinsic transmural and regional gradients in V_m and CaT in murine ventricular tissue.

A robust cardiac slicing approach was developed for optical mapping of transmural gradients in transmembrane potential (V_m) and intracellular Ca²⁺ transient (CaT) of murine heart.

Significant transmural gradients in V_m and CaT were observed in the left ventricle.

Frequency‐dependent action potentials and CaT alternans were observed in all ventricular regions with rapid pacing, with significantly greater incidence in the endocardium than epicardium.

The observations demonstrate the feasibility of our new approach to cardiac slicing for systematic analysis of intrinsic transmural and regional gradients in V_m and CaT.

Ventilation strategy and anesthesia management in patients with severe tracheal stenosis undergoing urgent tracheal stenting

BACKGROUND

Stenting of airway stenosis is a common procedure in specialized centers. The aim of this study was to summarize our clinical experience in ventilation strategy and anesthesia management of patients undergoing urgent tracheal stenting.

METHODS

Clinical data of 22 patients with severe tracheal stenosis who underwent urgent endoscopic placement of a tracheal stent during a 2-year period were retrospectively reviewed. The efficacy and safety of different ventilation strategies and veno-arterial extracorporeal membrane oxygenation (ECMO), individualized based on the cause and location of tracheal narrowing, were evaluated.

RESULTS

Sufficient ventilation was successfully established in all patients; ECMO was used in five patients with stenosis in the mid-trachea who were unable to tolerate conventional intubation; a laryngeal mask airway (LMA) was used in five patients with post-intubation tracheal stenosis; a cuffed tracheal tube was used in eight patients with lower tracheal stenosis; and low-frequency jet ventilation in rigid bronchoscopy was used in four patients with mid- or lower tracheal stenosis. Tracheal stents were successfully placed and there were significant improvements in dyspnea. There were significant increases in the partial pressure of carbon dioxide in patients ventilated with the LMA and cuffed tracheal tube. There was no hypoxia during the operative period.

CONCLUSION

Establishment of effective airway ventilation in patients with severe tracheal stenosis should be based on the cause, location, and severity of tracheal narrowing. Veno- arterial ECMO may be considered in patients with severe stenosis, if they are judged unable to tolerate conventional ventilation or jet ventilation.

Novel biomolecular information in rotenone-induced cellular model of Parkinson's disease

In order to uncover the remarkable pathogenic genes or molecular pathological process in Parkinson's disease (PD), we employed a microarray analysis upon the cellular PD model induced by rotenone. Compared to the control group, 2174 genes were screened out to be expressed differently in the rotenone-induced group by certain criterion. GO analysis and the pathways analysis showed the significant enrichment of genes that were associated with the biological process of cell cycle, apoptotic process, organelle fusion, mitochondrial lesion, endoplasmic reticulum stress and so on. Among these significant DE genes, some were sorted out to be involved in cell cycle and protein processing in endoplasmic reticulum. As the PPI network analysis showed, the interaction relationship of the DEGs involved in the process of protein generation in endoplasmic reticulum(ER) was clearly showed up. As a prediction, we emphasized the genes EDEM1, ATF4, TRAF2 might play central roles in the protein misfolding process during the progression of Parkinson's disease and these new-found genes might be the future research focus and therapeutic targets in PD.

Self-assembly of highly conductive self-n-doped fullerene ammonium halides and their application in the in situ solution-processable fabrication of working electrodes for alcohol electrooxidation

Self-assembled highly conductive fullerene ammonium halides are potential support of metal-based nanoparticles toward alcohol electrooxidation.

Microarray analysis of an synthetic α-synuclein induced cellular model reveals the expression profile of long non-coding RNA in Parkinson's disease

Long non-coding RNAs (lncRNAs) are a new research focus that are reported to influence the pathogenetic process of neurodegenerative disorders. To uncover new disease-associated genes and their relevant mechanisms, we carried out a gene microarray analysis based on a Parkinson's disease (PD) in vitro model induced by α-synuclein oligomers. This cellular model induced by 25 μmol/L α-synuclein oligomers has been confirmed to show the stable, transmissible neurotoxicity of α-synuclein, a typical PD pathological marker. And several differentially expressed lncRNAs and mRNAs were identified in this model, such as G046036, G030771, AC009365.4, RPS14P3, CTB-11I22.1, and G007549. Subsequent ceRNA analysis determined the potential relationships between these lncRNAs and their associated mRNAs and microRNAs. The results of the present study widen our horizon of PD susceptibility genes and provide new pathways towards efficient diagnostic biomarkers and therapeutic targets for PD.

Ovarian cancer stem cells promote tumour immune privilege and invasion via CCL5 and regulatory T cells

Emerging evidence indicates a link between the increased proportion of regulatory T cells (T_regs ) and reduced survival in patients who have been diagnosed with cancer. Cancer stem cells (CSCs) have been indicated to play a vital role in tumour initiation, drug resistance and recurrence. However, the relationship between T_regs and CSCs remains largely unknown. Here, we sorted out ovarian cancer stem-like side population (SP) cells and CD133⁺ cells to investigate the influence of ovarian CSCs on T_regs . Among the various immune-related molecules that we assessed, C-C motif chemokine ligand 5 (CCL5) was the most elevated in ovarian CSCs relative to that in the non-CSCs. The expression of its receptor, C-C motif chemokine receptor 5 (CCR5), was also increased on the surface of T_regs in ovarian cancer patients. This receptor-ligand expression profile indicated that ovarian CSCs recruit T_regs via CCL5-CCR5 interactions. We further assessed the expression of interleukin (IL)-10 in T_regs cultured with different cancer cells. T_regs cultured in conditioned medium (CM) from ovarian CD133⁺ cells expressed a higher level of IL-10 than T_regs cultured in CM from CD133^- cells, indicating that T_regs exert pronounced immune-inhibitory functions in CSC-rich environments. Furthermore, co-culture with ovarian cancer cell lines induced the expression of matrix metalloproteinase-9 (MMP9) in T_regs which, in turn, enhanced the degradation of the extracellular matrix and enabled the invasion of tumour cells, thereby facilitating tumour metastasis. For the first time, to our knowledge, our findings describe the relationship between ovarian CSCs and T_regs , and demonstrated that these two cell populations co-operate to promote tumour immune tolerance and enhance tumour progression.

The effect of probiotic Lactobacillus casei Shirota on knee osteoarthritis: a randomised double-blind, placebo-controlled clinical trial

Knee osteoarthritis (OA) treatment is challenging due to inefficacy and adverse effects of current medications. Probiotic treatment has been shown to promote bone metabolism, reduce pain and inflammatory responses of age-related musculoskeletal disorders, including OA. We aimed to investigate the effect of probiotic Lactobacillus casei Shirota (LcS) on patients with knee OA. 537 patients with knee OA were enrolled in this double-blind, placebo-controlled trial, who were randomised to receive skimmed milk containing either LcS or placebo daily for 6 months. Primary outcome was defined as changes in WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) and VAS (visual analog scale) scores. Secondary outcome was defined as changes in serum levels of high sensitivity C-reactive protein (hs-CRP). After 6 months of treatment, both WOMAC and VAS scores were significantly improved in the LcS groups of patients compared to the placebo group. Serum levels of hs-CRP were also significantly lower in patients receiving LcS than placebo. Strong linear correlations were observed between serum hs-CRP levels and WOMAC and VAS scores. LcS consumption could serve as a novel therapeutic option in the clinical management of knee OA, improving treatment outcome likely through reducing serum hs-CRP levels.

Inhibiting ERK/Mnk/eIF4E broadly sensitizes ovarian cancer response to chemotherapy

PURPOSE

To investigate whether ERK/MNK/eIF4E contributes chemoresistance in ovarian cancer.

METHODS

The phosphorylated levels of Erk, Mnk, and eIF4E were systematically analyzed in ovarian cancer patients before and after chemotherapy, and ovarian cancer cells exposed to short- and long-term chemo-agent treatment. The roles of Erk/Mnk/eIF4E were investigated using pharmacological and genetic approaches.

RESULTS

Increased phosphorylation levels of ERK, Mnk1, and eIF4E were observed in ovarian cancer cell exposed to chemotherapeutic agents, and paclitaxel-resistant SK-OV-3-r cells, and is a common response of ovarian cancer patients undergoing chemotherapy. MEK inhibitor U0126 inhibits basal and chemodrug-induced phosphorylation of ERK as well as Mnk1 and eIF4E, suggesting that Mnk1/eIF4E are the downstream signaling of ERK pathway and chemotherapy agents activate ERK/MNK/eIF4E in a MEK-dependent manner. eIF4E overexpression promotes ovarian cancer cell growth without affecting migration. In addition, ovarian cancer cells with eIF4E overexpression are more resistant to chemotherapeutic agents in aspect of growth inhibition and apoptosis induction compared to control cells. In contrast, eIF4E depletion augments chemotherapeutic agents' effect in ovarian cancer cells. These demonstrate that eIF4E play roles in growth and chemoresistance in ovarian cancer. MEK inhibitor U0126 also significantly enhances chemotherapeutic agents' inhibitory effects.

CONCLUSIONS

Our work shows that ERK/Mnk/eIF4E activation is critically involved in ovarian cancer chemoresistance and inhibiting ERK/Mnk/eIF4E broadly sensitizes ovarian cancer response to chemotherapy.