Three-dimensional pseudo-continuous arterial spin-labelled perfusion imaging for diagnosing upper cervical lymph node metastasis in patients with nasopharyngeal carcinoma: a whole-node histogram analysis

AIM

To evaluate whole-node histogram parameters of blood flow (BF) maps derived from three-dimensional pseudo-continuous arterial spin-labelled (3D pCASL) imaging in discriminating metastatic from benign upper cervical lymph nodes (UCLNs) for nasopharyngeal carcinoma (NPC) patients.

MATERIALS AND METHODS

Eighty NPC patients with a total of 170 histologically confirmed UCLNs (67 benign and 103 metastatic) were included retrospectively. Pre-treatment 3D pCASL imaging was performed and whole-node histogram analysis was then applied. Histogram parameters and morphological features, such as minimum axis diameter (MinAD), maximum axis diameter (MaxAD), and location of UCLNs, were assessed and compared between benign and metastatic lesions. Predictors were identified and further applied to establish a combined model by multivariate logistic regression in predicting the probability of metastatic UCLNs. Receiver operating characteristic (ROC) curves were used to analyse the diagnostic performance.

RESULTS

Metastatic UCLNs had larger MinAD and MinAD/MaxAD ratio, greater energy and entropy values, and higher incidence of level II (upper jugular group), but lower BF10th value than benign nodes (all p<0.05). MinAD, BF10th, energy, and entropy were validated as independent predictors in diagnosing metastatic UCLNs. The combined model yielded an area under the curve (AUC) of 0.932, accuracy of 84.42 %, sensitivity of 80.6 %, and specificity of 90.29 %.

CONCLUSIONS

Whole-node histogram analysis on BF maps is a feasible tool to differentiate metastatic from benign UCLNs in NPC patients, and the combined model can further improve the diagnostic efficacy.

Metformin ameliorates valve interstitial cell calcification by promoting autophagic flux

Calcific aortic valve disease (CAVD) is the most common heart disease of the developed world. It has previously been established that metformin administration reduces arterial calcification via autophagy; however, whether metformin directly regulates CAVD has yet to be elucidated. In the present study we investigated whether metformin alleviates valvular calcification through the autophagy-mediated recycling of Runx2. Calcification was reduced in rat valve interstitial cells (RVICs) by metformin treatment (0.5-1.5 mM) (P < 0.01), with a marked decrease in Runx2 protein expression compared to control cells (P < 0.05). Additionally, upregulated expression of Atg3 and Atg7 (key proteins required for autophagosome formation), was observed following metformin treatment (1 mM). Blocking autophagic flux using Bafilomycin-A1 revealed colocalisation of Runx2 with LC3 puncta in metformin treated RVICs (P < 0.001). Comparable Runx2 accumulation was seen in LC3 positive autolysosomes present within cells that had been treated with both metformin and hydroxychloroquine in combination (P < 0.001). Mechanistic studies employing three-way co-immunoprecipitation with Runx2, p62 and LC3 suggested that Runx2 binds to LC3-II upon metformin treatment in VICs. Together these studies suggest that the utilisation of metformin may represent a novel strategy for the treatment of CAVD.

The Potential Ability of Plan Complexity Metrics on the Dose Calculation and Plans Delivery in Intensity Modulated Radiotherapy

PURPOSE/OBJECTIVE(S)

The excessive modulation of treatment plan during radiotherapy (RT) increases the complexity. Evaluation of the multidimensional relationship between program complexity metrics, computation-based patient-specific quality assurance (PSQA), and conventional measurement-based PSQA could assist in enhancing the robustness of treatment planning, guide the allocation of clinical QA resources, and ultimately lessen QA workload.

MATERIALS/METHODS

The fifty-five metrics affecting RT planning and delivery accuracy were calculated by a house-built program to describe the complexity of 404 dynamic IMRT plans, with sensitivity to the small field, aperture position, MLC edge, low MUs, MLC leaf motion, leaf speed/acceleration, etc. The calculation-based PSQA was performed using Monte Carlo (MC) method and Collapsed Cone Convolution (CCC) algorithm, implemented in SciMoCa and Mobius 3D, respectively. The measurement-based PSQA was performed using 3D diode arrays with different geometries covering "O", "+" and " × " shapes which exist in ArcCheck, Delta4 phantom+ (Delta4) and Delta4PT phantom (Delta4PT), respectively. Gamma passing rates (GPRs) were recorded to measure the results of each QA system. This multidimensional relationship was evaluated using correlation analysis and principal component linear regression (PCR) analysis.

RESULTS

A total of 4448 GPRs for various QA systems corresponding to two Linacs were counted. The modulation index for speed (MIs) and modulation index for acceleration (MIa) were consistently located at the high points of the radarplots of the Spearman correlation coefficient |rs| between metrics and GPRs of the four QA systems, just except Delta4. Besides, the rs between SciMoCa and ArcCheck were 0.275-0.531 (P ≤ 0.001), SciMoCa and Delta4 were 0.32-0.418 (P ≤ 0.001), and Mobius 3Dand Delta4PT were 0.124-0.226 (P ≤ 0.05). The PCR model's coefficients determination (R2) for SciMoCa were 0.461-0.756 (P ≤ 0.001), ArcCheck were 0.243-0.440 (P ≤ 0.001), Delta4 were 0.268-0.402 (P ≤ 0.001), Mobius 3D were 0.299-0.407 (P ≤ 0.001), and Delta4PT were 0.087-0.141 (P ≤ 0.05).

CONCLUSION

This study is the first overall assessment of the impact of various complexity metrics on the accuracy of TPS calculation and Linac delivery. Of the metrics studied, MIs and MIa metrics have a standout impact on the ability of the TPS calculation and delivery system, extra attention should be paid during the planning process. It is inappropriate to utilize calculation-based QA to predict the results of measurement-based QA since there is a poor correlation between the two. Furthermore, calculation-based QA outperforms measurement-based QA in identifying highly complex plans, which can further guide clinical QA process optimization and save limited clinical resources.

Complexity Metrics and Planning Dose-Based Pretreatment Patient-Specific Quality Assurance Prediction: Classification, Gamma Passing Rates, and DVH Deviation

PURPOSE/OBJECTIVE(S)

Patient-specific quality assurance (QA) prediction before treatment is beneficial to the clinical resource allocation and the dosimetric monitoring of the patient plans. The aim of this study is to investigate the potential of complexity metrics of radiotherapy plan and patient planning dose to predict QA result, gamma passing rates and dose-volume indices deviation.

MATERIALS/METHODS

Planning dose from treatment planning system (TPS), reconstructed dose from a vendor provided QA phantom and complexity metrics of the 499 radiotherapy plans of patients in our institution from March 2022 to September 2022 were used for methodology verification. Gamma passing rate (3%/2mm,10% threshold) 90% was regarded as criterion of QA pass or fail. A deep learning model ResNet-50 was modified to 3D dose processing and a multilayer perceptron (MLP) with three layers were adopted to extract features from 3D dose and 1D metrics in two parallel ways, then, the features were concatenate together to predict QA results. The dataset was split into 349 for train, 50 for validation and 100 for testing. Evaluation of predictions was based on absolute value deviation and area under the curves (AUC) of receiver operator characteristic (ROC) curve.

RESULTS

In this dataset, 71% (355/499) plans pass the pretreatment QA test. For QA passing prediction in 100 testing cases, the AUC of ROC could achieve 0.92. For gamma passing rates prediction, a mean absolute error (MAE) of 1.8% could be observed for cases with gamma passing rates bigger than 90%, and a MAE of 4.5% deviation could be observed for cases with gamma passing rates from 80% to 90%. For PTV ΔD95 (%) and PTV ΔHI (%), the MAE of prediction and ground truth is 1%. The model with only complexity metrics and only 3D dose could achieve the AUC of ROC 0.91 and 0.84, respectively.

CONCLUSION

The complexity metrics and 3D planning dose-based model could predict pretreatment patient specific QA results with high accuracy and the complexity metrics play a leading role in the model. Dose-volume metrics deviations of PTV could be predicted and more clinically useful information could be provided.

Prediction Analysis of Dose Verification Based on Plan Complexity Metrics during Radiotherapy

PURPOSE/OBJECTIVE(S)

Plan validation in radiotherapy includes pre-treatment and in-treatment validation. It is feasible to leverage plan complexity to optimize validation processes, because some research reports that the consistency between planning and measurement or execution decreases as plan complexity increases. Therefore, starting from the plan complexity, this study comprehensively and systematically explores these factors affecting whether the plan verification is passed or not and the strength of their correlations, so as to establish a regression model and optimize the verification process.

MATERIALS/METHODS

The IMRT and model-based validation information were retrospectively collected for patients who received tumor radiotherapy at our institution from January 2020 to May 2022. The seventy-eight metrics characterizing the plan complexity were calculated and checked for each plan by an in-house developed computing platform. The comparisons of plan verification results under different tumor species and different verification methods were carried out, and the plan complexity metrics was also compared. Subsequently, Spearman correlation analysis between plan complexity and plan validation under different tumor species, different verification methods and different evaluation indexes was analyzed to provide the basis for regression analysis.

RESULTS

One thousand two hundred twenty-six patients were enrolled in the study. The plans in Eclipse TPS were performed by Varian Edge and iX linear accelerators and their verification were executed by EPID, Delat4, and ArcCheck. The gamma index under evaluation index of 3%/3mm, 3%/2mm, 2%/2mm, 1%/1mm were respectively 97.4% (7.1%), 94.8% (10.9%), 86.1% (20.1%), 50.7% (22.6%). The γ and DD of EPID and Detla4 decreased with the increase of TH, and the change of DD was the most significant, while the DTA of Detla4 did not change significantly with TH, and the passing rate of DTA and γ in thoracic and abdominal was the highest in ArcCheck group. Contrast and Variance were the most different between tumor types. The pelvic MIs and MIa were larger than those planned for the other three sites. Except for head and neck CLS and MD, other metrics did not vary significantly among tumor species. The correlation between the metrics characterizing the static characteristics of leaves was more significant for head and neck tumors; the correlation between metrics characterizing the flux complexity were significantly different in pelvic. There was a correlation between plan complexity and γ indicators, and the overall strength was ArcCheck > EPID > Delta4 for head and neck, Delta4 > EPID and ArcCheck for thorax-abdomen, Delta4 and EPID > ArcCheck for pelvic, Delta4 > ArcCheck > EPID for arms and legs.

CONCLUSION

There was a correlation between different plan complexity metrics. Based on this study, it is feasible to predict the verification results based on these complexity metrics, but the regression models were respectively established according to tumor types and validation methods.

[Analysis of distribution characteristics of specific immunoglobulin E in 8 092 children with eczema and urticaria in a hospital of pediatric in Tianjin City]

To investigate the common specific immunoglobulin E(sIgE) in children with eczema and urticaria, compare the allergies in children with different diseases, genders and ages, and provide the scientific basis for the prevention, diagnosis and treatment. A retrospective study was conducted to analyze the children who were suspected of eczema and urticaria and tested for serum sIgE in the Tianjin Children's Hospital from December 2019 to August 2021. A total of 8 092 serum samples were tested for ten food allergens and ten inhaled allergens. The method was the enzyme-linked immune capture assay. The allergen epidemiological characteristics were statistically analyzed by Chi square test based on the children's characteristics and factors such as different sexes and ages and by the mass data. The results showed that the positive rate of eczema was 64.42%(5 213/8 092), and the urticaria was 35.58%(2 879/8 092). The positive rate of specific IgE was 66.65%(5 393/8 092), the food allergens was 61.74%(4 996/8 092), and the inhaled allergens was 34.85%(2 820/8 092). The top three positive rates of food allergens were egg 46.65%(3 775/8 092), milk 32.64%(2 641/8 092) and wheat flour 15.08%(1 220/8 092). The top three positive rates of inhaled allergens were house dust 21.40%(1 732/8 092), Alternaria 11.78%(953/8 092) and Dermatophagoides farinae 7.33%(593/8 092). The positivity of food allergens and inhaled allergens was significantly different in different age groups. The positive rates of food allergens in different age groups were 48.92%(947/1 936) in<1 year old, 72.28%(2 680/3 708) in 1-3 years old, 64.58%(919/1 423) in 4-6 years old and 43.90%(450/1 025) in>6 years old. The positive rates of inhaled allergens in different age groups were 17.67%(342/1 936) in<1 year old, 36.35%(1 348/3 708) in 1-3 years old, 46.38%(660/1 423) in 4-6 years old and 45.85%(470/1 025) in>6 years old. The top six positive rates of allergens of eczema were the same with urticaria, which were egg, milk, house dust, wheat flour, Alternaria and Dermatophagoides farinae. The allergens (greater than or equal to grade 4) differed in children with eczema and urticaria. Moreover, there were significant differences in the positive rates of Alternaria, egg, wheat flour, crab and shrimp. In conclusion, this study can reflect the epidemic characteristics of allergens in children with eczema and urticaria to a certain extent. There were significant differences in the positive rates of allergens between different age groups. It is necessary to reasonably avoid the high-risk allergens according to the epidemiological characteristics and clinical symptoms, which provide valuable information for the prevention, diagnosis and treatment of allergic diseases.

Associated factors and abnormal dorsal raphe nucleus connectivity patterns of freezing of gait in Parkinson's disease

BACKGROUND

Freezing of gait (FOG) is a common, disabling symptom of Parkinson's disease (PD), and its exact pathophysiological mechanism is still poorly understood. The control of gait is a complex process that may be influenced by emotions modulated by serotonergic networks. Therefore, this study aimed to determine factors associated with FOG in PD patients and to evaluate the importance of the dorsal raphe nucleus (DRN; central node in the serotoninergic system) in FOG pathophysiology.

METHODS

We combined cross-sectional survey data from 453 PD patients. According to the Freezing of Gait Questionnaire (FOGQ), patients were divided into two groups: the "PD with frozen gait (PD-FOG)" and "PD without frozen gait (PD-nFOG)" groups. Demographic characteristics, clinical features, and motor and nonmotor symptoms (NMS) assessments of PD patients were recorded. Univariate statistical analysis was performed between the two groups, and then regression analysis was performed on related factors. We also acquired resting-state functional MRI (rs-fMRI) data from 20 PD-FOG, 21 PD-nFOG, and 22 healthy controls (HCs) who were randomly chosen. We defined seeds in the DRN to evaluate functional connectivity (FC) patterns.

RESULTS

The overall frequency of FOG was 11.9% patients in the PD-FOG group were older, had a longer disease duration, had a higher levodopa equivalent daily dose, had more severe motor symptoms and worse quality of life, had a higher proportion of dyskinesia, wearing-off and postural instability/gait difficulty (PIGD) clinical phenotype, and experienced more depression and impaired sleep function than those in the PD-nFOG group. Logistic regression analysis showed that H&Ystage ≥ 3, UPDRS-III scores, PIGD clinical phenotype and excessive daytime sleepiness were associated with FOG. In addition, there was significantly lower FC between the DRN and some cortical structures, including the supplementary motor area (SMA), left superior frontal gyrus (SFG), and left median cingulated cortex (MCC) in PD-FOG patients than HCs and PD-nFOG patients.

CONCLUSIONS

These results demonstrate that the severity of PD and PIGD clinical phenotype are associated factors for freezing and that DRN dysfunction may play a key role in PD-related NMS and FOG. An abnormal cortical and brainstem networks may contribute to the mechanisms underlying FOG.

Differences in cardiometabolic risk profiles between Chinese and Finnish older adults with glucose impairment and central obesity

BACKGROUND

Obesity and ethnicity play important roles in cardiovascular complications in patients with type 2 diabetes mellitus (T2DM). This study aimed to compare cardiometabolic risk profiles between Chinese and Finnish older adults of central obesity with prediabetes or T2DM.

METHODS

Study subjects were 60-74 years old and originated from two population samples. The Finnish subjects came from the Kuopio Ischemic Heart Disease (KIHD) study (n = 1089), and the Chinese subjects came from the Shanghai High-risk Diabetic Screen (SHiDS) study (n = 818). The KIHD and SHiDS studies used similar questionnaires to determine participants' baseline characteristics regarding the history of medication use and diseases and lifestyle factors. All study subjects participated in glucose tolerance tests and anthropometry assessments, including waist circumference measurements.

RESULTS

Among study subjects of central obesity with prediabetes (n = 298), fasting and 2-h glucose, and fasting insulin and insulin resistance were significantly higher in Chinese than in Finnish (p < 0.0001-0.016). In addition, triglyceride (TG) level was higher and the low-density lipoprotein cholesterol (LDL) and LDL to high-density lipoprotein cholesterol (HDL) ratio were lower in Chinese than in Finnish (p < 0.0001-0.003). Among subjects of central obesity with T2DM (n = 251), Chinese subjects had significantly less proportions of antihypertensive, glycaemic control medication, and statin users as well as lower level of physical activity (p < 0.0001 for all), while higher blood pressure (p = 0.002 for systolic blood pressure and p < 0.0001 for diastolic blood pressure), TG levels (p < 0.05) and HDL (p = 0.002) than the Finnish counterparts. There were no differences in β-cell function (HOMA-β) between Chinese and Finnish both in prediabetes and T2DM.

CONCLUSIONS

Our results indicated that Chinese and Finnish older adults of central obesity with prediabetes and T2DM had similar β-cell function. However, Chinese individuals with prediabetes are prone to insulin resistance. Meanwhile, lipid metabolism dysfunction is also different between Chinese and Finnish. Chinese older adults of central obesity with prediabetes showed higher TG, but Finnish showed higher LDL and LDL/HDL. Strategic for T2DM prevention and treatment should be ethnically specific.

[Research progress of anesthesia methods in prostate biopsy]

Prostate biopsy is the gold standard for the diagnosis of prostate cancer. In order to successfully and effectively complete the biopsy, clinicians should not only select the correct puncture method, but also pay attention to the pain control of patients undergoing puncture. It is necessary to select a reasonable anesthetic method for biopsy. The pain during biopsy comes from the skin, muscle and other structures in the puncture approach, and also comes from the prostate capsule. Therefore, the anesthesia emphasis of transperineal and transrectal biopsy approaches will also be different. The use of appropriate anesthesia is of great significance to improve the patient's cooperation and ensure the success rate of biopsy. With the continuous maturity of the technology and concept of prostate biopsy, a single anesthesia method has been unable to meet the actual anesthetic needs of biopsy, and the use of multi-site and multi-phase combined anesthesia for different sources of pain has become the mainstream anesthetic option.

MicroRNA-409-3p Targeting at ATXN3 Reduces the Apoptosis of Dopamine Neurons Based on the Profile of miRNAs in the Cerebrospinal Fluid of Early Parkinson's Disease

Precise recognition of early Parkinson’s disease (PD) has always been a challenging task requiring more feasible biomarkers to be integrated to improve diagnostic accuracy. MicroRNAs (miRNAs) of cerebrospinal fluid (CSF) are believed to be potential and promising candidate biomarkers for PD. However, the role of altered miRNAs of CSF play in PD is unclear. Here, we recruited patients with early stages of PD and controls to analyze the expression of miRNA in CSF by the Next Generation Sequencing (NGS). Furthermore, we tested the levels of these miRNA in SH-SY5Y cells treated with MPP⁺ using real-time quantitative PCR. We found 21 miRNAs were upregulated in CSF of early PD patients and miR-409-3p, one of the identified 21 miRNAs, was further confirmed in SH-SY5Y cells treated with MPP⁺. Also, more cells survived in the overexpression of the miR-409-3p group when SH-SY5Y cells and mice were treated with MPP⁺ and MPTP, respectively. Mechanistically, we demonstrated the binding of miR-409-3p and 3’UTR of ATXN3 through a dual luciferase reporter gene assay. Moreover, miR-409-3p mimic reduced the aggregation of polyglutamine-expanded mutant of ATXN3 and apoptosis. Our results provide experimental evidence for miR-409-3p in CSF as a diagnostic marker of PD.

Three-dimensional Quantification of Enamel Preservation in Tooth Preparation for Porcelain Laminate Veneers: A Fully Digital Workflow In Vitro Study

OBJECTIVE

This in vitro study aimed to evaluate the preservation of enamel after tooth preparation for porcelain laminate veneers (PLVs) at different preparation depths based on a fully digital workflow.

METHODS AND MATERIALS

Sixty extracted human maxillary anterior teeth, including 20 maxillary central incisors (MCIs), 20 maxillary lateral incisors (MLIs), and 20 maxillary canines (MCs) underwent microcomputed tomography (CT) scanning, and were reconstructed as three-dimensional (3D) enamel and dentin models. Subsequently, the three-dimensional (3D) enamel models were imported into Materialise, where each enamel model underwent seven types of virtual preparation for PLVs at preparation depths at 0.1-mm increments from 0.1-0.3-0.5 mm (D1) to 0.7-0.9-1.1 mm (D7). The enamel surface was depicted by merging the virtual preparation and, respective, dentin models. The enamel area and prepared surface were measured to calculate the percentage of enamel (R%). The data were statistically analyzed using one-way analysis of variance (ANOVA) (α=0.05).

RESULTS

The group-wise mean (standard deviation) R values for the MCIs were as follows: D1-D3: 100.00 (0) each, and D4-D7: 74.70 (2.45), 51.40 (5.12), 24.40 (3.06), and 0.00 (0), respectively. The group-wise mean R values for the MLIs were 100.00 (0), 73.70 (3.40), 53.50 (3.44), 25.20 (3.79), and 0.90 (0.99) for the D1-D5 groups, respectively; and 0.00 (0) each for the D6-D7 groups. The group-wise mean (standard deviations) R values for the MCs were as follows: D1-D3: 100.00 (0) each, and D4-D7: 99.00 (1.34), 77.10 (3.28), 74.20 (3.61), and 52.20 (4.09), respectively. The one-way ANOVA revealed significant differences between the seven groups in the MCIs, MLIs, and MCs (p<0.05).

CONCLUSIONS

Our results recommended preparation depths of up to 0.3-0.5-0.7 mm (MCIs), 0.1-0.3-0.5 mm (MLIs), and 0.4-0.6-0.8 mm (MCs) to facilitate complete intraenamel preparation. Moreover, 50% enamel was preserved at preparation depths of 0.5-0.7-0.9 mm (MCIs), 0.3-0.5-0.7 mm (MLIs), and 0.7-0.9-1.1 mm (MCs).

Assessing the Effects of Vitamin D on Neural Network Function in Patients With Parkinson's Disease by Measuring the Fraction Amplitude of Low-Frequency Fluctuation

Background: Recently, many studies have shown that low vitamin D (VD) levels may be related to an increased risk of Parkinson's disease (PD), but the underlying mechanisms remain unclear. Objective: To explore the relationship between PD and VD levels, as well as to analyze the effects of VD on spontaneous brain activity and explore the possible mechanism of its involvement in PD risk. Methods: In a cross-sectional study, we quantified the difference in VD levels between 330 PD patients and 209 healthy controls (HC) to explore the correlation between VD and PD risk. We also acquired resting-state Functional Magnetic Resonance Imaging (rs-fMRI) data from 46 PD patients and 21 HC. The PD patients were divided into three groups according to 25(OH)D levels: PD patients with VD deficiency (PD + VDD), PD patients with VD insufficiency (PD + VDI), and PD patients with normal VD (PD + NVD). The effect of VD status on spontaneous neuronal activity in the whole brain was analyzed by measuring the fraction amplitude of low-frequency fluctuation (fALFF). Results: Compared with HC, the PD patients had lower serum 25(OH)D levels (23.60 ± 7.27 vs. 25.60 ± 5.78, P < 0.001). The 25(OH)D level may have a potential dose-dependent effect on the risk of PD (P _trend = 0.007). A high risk of PD was associated with VD deficiency [25(OH)D < 20 ng/mL, OR = 2.319], and the lowest quartile of 25(OH)D concentration was associated with a high risk of PD (OR = 1.941). In the rs-fMRI study, PD + VDD patients had wider brain regions with altered fALFF than other PD groups when compared with the corresponding HC groups. Both PD + VDD and PD + VDI showed higher fALFF in the cuneus, left precuneus, calcarine cortex and right lingual, as well as lower fALFF in the left middle temporal gyrus. PD + VDD patients also showed higher fALFF in the left superior, middle and inferior frontal gyri, as well as the left precentral gyrus than HC. Among PD patients, there was only a statistically significant difference in fALFF between the PD + VDD and PD + NVD groups. Compared with the PD + NVD group, PD + VDD patients exhibited higher fALFF in the left precentral and left postcentral gyrus, as well as the left inferior parietal lobule. Conclusion: These results demonstrate that PD patients had lower serum VD levels than HC, and VD may have a potential dose-dependent effect on PD risk. Lower serum VD levels can affect the spontaneous neuronal activity of default-mode network (DMN) and visual pathway neurons in PD patients, providing a possible mechanism for its effect on PD risk.

Hydrokinetic pancreatic function and insulin secretion are moduled by Cl- uniporter Slc26a9 in mice

AIM

Slc26a9 is a member of the Slc26 multifunctional anion transporter family. Polymorphisms in Slc26a9 are associated with an increased incidence of meconium ileus and diabetes in cystic fibrosis patients. We investigated the expression of Slc26a9 in the murine pancreatic ducts, islets and parenchyma, and elucidated its role in pancreatic ductal electrolyte and fluid secretion and endocrine function.

METHODS

Pancreatic Slc26a9 and CFTR mRNA expression, fluid and bicarbonate secretion were assessed in slc26a9^-/- mice and their age- and sex-matched wild-type (wt) littermates. Glucose and insulin tolerance tests were performed.

RESULTS

Compared with stomach, the mRNA expression of Slc26a9 was low in pancreatic parenchyma, 20-fold higher in microdissected pancreatic ducts than parenchyma, and very low in islets. CFTR mRNA was ~10 fold higher than Slc26a9 mRNA expression in each pancreatic cell type. Significantly reduced pancreatic fluid secretory rates and impaired glucose tolerance were observed in female slc26a9^-/- mice, whereas alterations in male mice did not reach statistical significance. No significant difference was observed in peripheral insulin resistance in slc26a9^-/- compared to sex- and aged-matched wt controls. In contrast, isolated slc26a9^-/- islets in short term culture displayed no difference in insulin content, but a significantly reduced glucose-stimulated insulin secretion compared to age- and sex-matched wt islets, suggesting that the impaired glucose tolerance in the absence of Slc26a9 expression these is a pancreatic defect.

CONCLUSIONS

Deletion of Slc26a9 is associated with a reduction in pancreatic fluid secretion and impaired glucose tolerance in female mice. The results underline the importance of Slc26a9 in pancreatic physiology.

[RIP1/RIP3-MLKL signaling pathway correlates with occurrence, progression and prognosis of chronic heart failure]

OBJECTIVE

To detect plasma levels of receptor-interacting protein kinase 1 (RIP1), RIP3 and mixed lineage kinase domain-like protein (MLKL) in patients with chronic heart failure and explore the expression pattern of programmed necrosis signaling pathway RIP1/RIP3-MLKL in the progression of heart failure.

METHODS

The patients with chronic heart failure (NYHA class Ⅱ-Ⅳ) admitted in our hospital between February, 2020 and March, 2021 were prospectively enrolled in this study, with 21 healthy volunteers as the control group. The enrolled patients included 20 with grade Ⅱ, 33 with grade Ⅲ, and 43 with grade Ⅳ cardiac function. Fasting venous blood was collected from all the participants for detecting plasma levels of RIP1, RIP3, and MLKL and protein expressions of RIP1/RIP3-MLKL pathway using enzyme-linked immunosorbent assay (ELISA) and Western blotting. The patients with grade Ⅳ cardiac function were followed up for 5 months to evaluate the clinical prognostic indicators.

RESULTS

Compared with the healthy volunteers, the patients with grade Ⅱ, Ⅲ and Ⅳ cardiac function had significantly increased plasma levels of RIP1, RIP3, and MLKL (P < 0.01), and their levels were significantly higher in grade Ⅲ/Ⅳ patients than in those with grade Ⅱ cardiac function (P < 0.01); the plasma levels of RIP1 and MLKL were significantly higher in grade Ⅳ patients than in grade Ⅲ patients (P < 0.05). The results of Western blotting also showed increased expressions of the proteins in the RIP1/RIP3-MLKL pathway in patients with heart failure. Pearson correlation analysis suggested that in patients with heart failure, the expression levels of RIP1, RIP3, and MLKL were positively correlated with SCR, AST, LVEDD and NT-proBNP (P < 0.05). Follow-up study of the patients with grade Ⅳ cardiac function showed that higher expression levels of RIP1/RIP3-MLKL were associated with a poorer prognosis of the patients.

CONCLUSION

The expressions of RIP1, RIP3 and MLKL are significantly upregulated in patients with heart failure in positive correlation with the severity of the disease condition, and the activation of the RIP1/RIP3-MLKL signaling pathway may contribute to the occurrence, development and prognosis of chronic heart failure.