Genkwanin alleviates intervertebral disc degeneration via regulating ITGA2/PI3K/AKT pathway and inhibiting apoptosis and senescence

Intervertebral disc degeneration (IVDD) is a progressive degenerative disease influenced by various factors. Genkwanin, a known anti-inflammatory flavonoid, has not been explored for its potential in IVDD management. This study aims to investigate the effects and mechanisms of genkwanin on IVDD. In vitro, cell experiments revealed that genkwanin dose-dependently inhibited Interleukin-1β-induced expression levels of inflammatory factors (Interleukin-6, inducible nitric oxide synthase, cyclooxygenase-2) and degradation metabolic protein (matrix metalloproteinase-13). Concurrently, genkwanin upregulated the expression of synthetic metabolism genes (type II collagen, aggrecan). Moreover, genkwanin effectively reduced the phosphorylation of phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin, mitogen-activated protein kinase (MAPK), and nuclear factor-κB (NF-κB) pathways. Transcriptome sequencing analysis identified integrin α2 (ITGA2) as a potential target of genkwanin, and silencing ITGA2 reversed the activation of PI3K/AKT pathway induced by Interleukin-1β. Furthermore, genkwanin alleviated Interleukin-1β-induced senescence and apoptosis in nucleus pulposus cells. In vivo animal experiments demonstrated that genkwanin mitigated the progression of IVDD in the rat model through imaging and histological examinations. In conclusion, This study suggest that genkwanin inhibits inflammation in nucleus pulposus cells, promotes extracellular matrix remodeling, suppresses cellular senescence and apoptosis, through the ITGA2/PI3K/AKT, NF-κB and MAPK signaling pathways. These findings indicate that genkwanin may be a promising therapeutic candidate for IVDD.

The relationship between imaging features, therapeutic response, and overall survival in pediatric diffuse intrinsic pontine glioma

We aimed to evaluate the relationship between imaging features, therapeutic responses (comparative cross-product and volumetric measurements), and overall survival (OS) in pediatric diffuse intrinsic pontine glioma (DIPG). A total of 134 patients (≤ 18 years) diagnosed with DIPG were included. Univariate and multivariate analyses were performed to evaluate correlations of clinical and imaging features and therapeutic responses with OS. The correlation between cross-product (CP) and volume thresholds in partial response (PR) was evaluated by linear regression. The log-rank test was used to compare OS patients with discordant therapeutic response classifications and those with concordant classifications. In univariate analysis, characteristics related to worse OS included lower Karnofsky, larger extrapontine extension, ring-enhancement, necrosis, non-PR, and increased ring enhancement post-radiotherapy. In the multivariate analysis, Karnofsky, necrosis, extrapontine extension, and therapeutic response can predict OS. A 25% CP reduction (PR) correlated with a 32% volume reduction (R2 = 0.888). Eight patients had discordant therapeutic response classifications according to CP (25%) and volume (32%). This eight patients' median survival time was 13.0 months, significantly higher than that in the non-PR group (8.9 months), in which responses were consistently classified as non-PR based on CP (25%) and volume (32%). We identified correlations between imaging features, therapeutic responses, and OS; this information is crucial for future clinical trials. Tumor volume may represent the DIPG growth pattern more accurately than CP measurement and can be used to evaluate therapeutic response.

A prospective cohort-based artificial intelligence evaluation system for the protective efficacy and immune response of SARS-CoV-2 inactivated vaccines

BACKGROUND

Novel coronaviruses constitute a significant health threat, prompting the adoption of vaccination as the primary preventive measure. However, current evaluations of immune response and vaccine efficacy are deemed inadequate.

OBJECTIVES

The study sought to explore the evolving dynamics of immune response at various vaccination time points and during breakthrough infections. It aimed to elucidate the synergistic effects of epidemiological factors, humoral immunity, and cellular immunity. Additionally, regression curves were used to determine the correlation between the protective efficacy of the vaccine and the stimulated immune response.

METHODS

Employing LASSO for high-dimensional data analysis, the study utilised four machine learning algorithms-logistical regression, random forest, LGBM classifier, and AdaBoost classifier-to comprehensively assess the immune response following booster vaccination.

RESULTS

Neutralising antibody levels exhibited a rapid surge post-booster, escalating to 102.38 AU/mL at one week and peaking at 298.02 AU/mL at two weeks. Influential factors such as sex, age, disease history, and smoking status significantly impacted post-booster antibody levels. The study further constructed regression curves for neutralising antibodies, non-switched memory B cells, CD4+T cells, and CD8+T cells using LASSO combined with the random forest algorithm.

CONCLUSION

The establishment of an artificial intelligence evaluation system emerges as pivotal for predicting breakthrough infection prognosis after the COVID-19 booster vaccination. This research underscores the intricate interplay between various components of immunity and external factors, elucidating key insights to enhance vaccine effectiveness. 3D modelling discerned distinctive interactions between humoral and cellular immunity within prognostic groups (Class 0-2). This underscores the critical role of the synergistic effect of humoral immunity, cellular immunity, and epidemiological factors in determining the protective efficacy of COVID-19 vaccines post-booster administration.

Ascorbic acid biosynthesis in Pacific abalone Haliotis discus hannai Ino and L-gulonolactone oxidase gene loss as an independent event

Up to now, it has been believed that invertebrates are unable to synthesize ascorbic acid (AA) in vivo. However, in the present study, the full-length CDs (Coding sequence) of L-gulonolactone oxidase (GLO) from Pacific abalone (Haliotis discus hannai Ino) were obtained through molecular cloning. The Pacific abalone GLO contained a FAD-binding domain in the N-termination, and ALO domain and conserved HWAK motif in the C-termination. The GLO gene possesses 12 exons and 11 introns. The Pacific abalone GLO was expressed in various tissues, including the kidney, digestive gland, gill, intestine, muscle and mantle. The GLO activity assay revealed that GLO activity was only detected in the kidney of Pacific abalone. After a 100-day feeding trial, dietary AA levels did not significantly affect the survival, weight gain, daily increment in shell length, and feed conversion ratio of Pacific abalone. The expression of GLO in the kidney was downregulated by dietary AA. These results implied that the ability to synthesize AA in abalone had not been lost. From the evolutionary perspective, the loss of GLO occurred independently as an independent event by matching with the genomes of various species. The positive selection analysis revealed that the GLO gene underwent purifying selective pressure during its evolution. In conclusion, the present study provided direct evidence to prove that the GLO activity and the ability to synthesize AA exist in abalone. The AA synthesis ability in vertebrates might have originated from invertebrates dating back 930.31 million years.

Development and validation of a nomogram to predict leptomeningeal metastases in lung adenocarcinoma: Cervical lymph node metastasis is an important association factor

BACKGROUND

The goal of this study was to create a nomogram using routine parameters to predict leptomeningeal metastases (LMs) in advanced lung adenocarcinoma (LAC) patients to prevent needless exams or lumbar punctures and to assist in accurately diagnosing LMs.

METHODS

Two hundred and seventy-three patients with LMs and brain metastases were retrospectively reviewed and divided into derivation (n = 191) and validation (n = 82) cohorts using a 3:7 random allocation. All LAC patients with LMs had positive cerebrospinal fluid cytology results and brain metastases confirmed by magnetic resonance imaging. Binary logistic regression with backward stepwise selection was used to identify significant characteristics. A predictive nomogram based on the logistic model was assessed through receiver operating characteristic curves. The validation cohort and Hosmer-Lemeshow test were used for internal validation of the nomogram.

RESULTS

Five clinicopathological parameters, namely, gene mutations, surgery at the primary lung cancer site, clinical symptoms of the head, N stage, and therapeutic strategy, were used as predictors of LMs. The area under the curve was 0.946 (95% CI 0.912-0.979) for the training cohort and 0.861 (95% CI 0.761-0.961) for the internal validation cohort. There was no significant difference in performance between the two cohorts (p = 0.116). In the internal validation, calibration plots revealed that the nomogram predictions were well suited to the actual outcomes.

CONCLUSIONS

We created a user-friendly nomogram to predict LMs in advanced lung cancer patients, which could help guide treatment decisions and reduce unnecessary lumbar punctures.

Distinguishing EGFR mutation molecular subtypes based on MRI radiomics features of lung adenocarcinoma brain metastases

OBJECTIVE

To explore the feasibility of identifying epidermal growth factor receptor (EGFR) mutation molecular subtypes in primary lesions based on the radiomics features of lung adenocarcinoma brain metastases using magnetic resonance imaging (MRI).

METHODS

We retrospectively analyzed clinical, imaging, and genetic testing data of patients with lung adenocarcinoma with EGFR gene mutations who had brain metastases. Three-dimensional radiomics features were extracted from contrast-enhanced T1-weighted images. The volume of interest was delineated and normalized using Z-score, dimensionality reduction was performed using principal component analysis, feature selection using Relief, and radiomics model construction using adaptive boosting as a classifier. Data were randomly divided into training and testing datasets at an 8:2 ratio. Five-fold cross-validation was conducted in the training set to select the optimal radiomics features and establish a predictive model for distinguishing between exon 19 deletion (19Del) and exon 21 L858R point mutation (21L858R), the two most common EGFR gene mutations. The testing set was used for external validation of the models. Model performance was evaluated using receiver operating characteristic curve and decision curve analyses.

RESULTS

Overall, 86 patients with 228 brain metastases were included. Patient age was identified as an independent predictor for distinguishing between 19Del and 21L858R. The area under the curve (AUC) values of the radiomics model in the training and testing datasets were 0.895 (95% confidence interval [CI]: 0.850-0.939) and 0.759 (95% CI: 0.0.614-0.903), respectively. The AUC for diagnosis of all cases using a combined model of age and radiomics was 0.888 (95% CI: 0.846-0.930), slightly higher than that of the radiomics model alone (0.866, 95% CI: 0.820-0.913), but without statistical significance (p=0.1626). In the decision curve analysis, both models demonstrated clinical net benefits.

CONCLUSIONS

The radiomics model based on MRI of lung adenocarcinoma brain metastases could distinguish between EGFR 19Del and 21L858R mutations in the primary lesion.

A prognostic model for SARS-CoV-2 breakthrough infection: Analyzing a prospective cellular immunity cohort

BACKGROUND

Following the COVID-19 pandemic, studies have identified several prevalent characteristics, especially related to lymphocyte subsets. However, limited research is available on the focus of this study, namely, the specific memory cell subsets among individuals who received COVID-19 vaccine boosters and subsequently experienced a SARS-CoV-2 breakthrough infection.

METHODS

Flow cytometry (FCM) was employed to investigate the early and longitudinal pattern changes of cellular immunity in patients with SARS-CoV-2 breakthrough infections following COVID-19 vaccine boosters. XGBoost (a machine learning algorithm) was employed to analyze cellular immunity prior to SARS-CoV-2 breakthrough, aiming to establish a prognostic model for SARS-CoV-2 breakthrough infections.

RESULTS

Following SARS-CoV-2 breakthrough infection, naïve T cells and TEMRA subsets increased while the percentage of TCM and TEM cells decreased. Naïve and non-switched memory B cells increased while switched and double-negative memory B cells decreased. The XGBoost model achieved an area under the curve (AUC) of 0.78, with an accuracy rate of 81.8 %, a sensitivity of 75 %, and specificity of 85.7 %. TNF-α, CD27-CD19+cells, and TEMRA subsets were identified as high predictors. An increase in TNF-α, cTfh, double-negative memory B cells, IL-6, IL-10, and IFN-γ prior to SARS-CoV-2 infection was associated with enduring clinical symptoms; conversely, an increase in CD3+ T cells, CD4+ T cells, and IL-2 was associated with clinical with non-enduring clinical symptoms.

CONCLUSION

SARS-CoV-2 breakthrough infection leads to disturbances in cellular immunity. Assessing cellular immunity prior to breakthrough infection serves as a valuable prognostic tool for SARS-CoV-2 infection, which facilitates clinical decision-making.

Exploring the Potential of Pretrained CNNs and Time-Frequency Methods for Accurate Epileptic EEG Classification: A Comparative Study

Prompt diagnosis of epilepsy relies on accurate classification of automated electroencephalogram (EEG) signals. Several approaches have been developed to characterize epileptic EEG data; however, none of them have exploited time-frequency data to evaluate the effect of tweaking parameters in pretrained frameworks for EEG data classification. This study compares the performance of several pretrained convolutional neural networks (CNNs) namely, AlexNet, GoogLeNet, MobileNetV2, ResNet-18 and SqueezeNet for the localization of epilepsy EEG data using various time-frequency data representation algorithms. Continuous wavelet transform (CWT), empirical Fourier decomposition (EFD), empirical mode decomposition (EMD), empirical wavelet transform (EWT), and variational mode decomposition (VMD) were exploited for the acquisition of 2D scalograms from 1D data. The research evaluates the effect of multiple factors, including noisy versus denoised scalograms, different optimizers, learning rates, single versus dual channels, model size, and computational time consumption. The benchmark Bern Barcelona EEG dataset is used for testing purpose. Results obtained show that the combination of MobileNetV2, Continuous Wavelet Transform (CWT) and Adam optimizer at a learning rate of 10^-4, coupled with dual-data channels, provides the best performance metrics. Specifically, these parameters result in optimal sensitivity, specificity, f1-score, and classification accuracy, with respective values of 96.06%, 96.15%, 96.08%, and 96.10%. To further corroborate the efficacy of opted pretrained models on exploited Signal Decomposition (SD) algorithms, the classifiers are also being simulated on Temple University database at pinnacle modeling composition. A similar pattern in the outcome readily validate the findings of our study and robustness of deep learning models on epilepsy EEG scalograms.The conclusions drawn emphasize the potential of pretrained CNN-based models to create a robust, automated system for diagnosing epileptiform. Furthermore, the study offers insights into the effectiveness of varying time-frequency techniques and classifier parameters for classifying epileptic EEG data.

Conventional HE staining combined with two special staining methods to identify antemortem stab wound in case with highly decomposed mutilated corpses

This study aims to identify an antemortem neck stab wound on a highly decomposed, headless and mutilated body by conventional hematoxylin-eosin (HE) staining combined with Ponceau-Victoria blue B staining (P-VB staining) and Masson staining. Specifically, a tissue sample was excised from the skin and muscle tissue at the junction of the normal and brownish discolored areas around the suspected stabbing tract of the left neck, in the upper and lower wound-clavicle-shoulder region. Conventional HE staining only provides a morphological and structural outline of the tissue, with both the injury hemorrhage and local connective tissue appearing eosinophilic pink. However, P-VB staining shows obvious contrast between the injury hemorrhage and connective tissue, with the former appearing yellow-green and the latter appearing orange-red. Similarly, Masson staining of the injury hemorrhage and connective tissue contrast clearly with purple-red and dark blue, respectively. Therefore, our study highlights that conventional HE staining with the combination of P-VB staining and Masson staining allowed for a clearer and corroborated identification of antemortem injury and hemorrhage from the stab wound in highly decomposed mutilated corpses.

Architecture engineering of Fe/Fe2O3@MoS2 enables highly efficient tetracycline remediation via peroxymonosulfate activation: Critical roles of adsorption capacity and redox cycle regulation

Design and synthesis of high-efficiency multicomponent nanostructure for activating peroxymonosulfate (PMS) to destruct emerging antibiotics remains a daunting challenge. We report herein the simplest one-step hydrothermal construction of hierarchical Fe/Fe2O3@MoS2 architecture composed of MoS2 nanosheets integrated commercial Fe2O3 nanoparticles. The fabricated Fe/Fe2O3@MoS2 architecture can be utilized as an efficient PMS activator to destruct tetracycline hydrochloride (TCH) with a removal efficiency of 90.3 % within 40 min, outperforming Fe2O3 nanoparticles, MoS2 nanosheets analogues and many MoS2-based materials. The Fe/Fe2O3@MoS2/PMS works well under various reaction conditions, and SO4•- and 1O2 are identified as major reactive oxygen species. Thirteen intermediates towards TCH destruction are detected via four pathways, and their acute/chronic toxicity and phytotoxicity are assessed. The origins of Fe/Fe2O3@MoS2/PMS system for efficient degrading TCH are ascribed to the synergy catalysis between Fe2O3 and MoS2, which originate from: (a) the exposed Mo4+ sites on catalyst surface facilitating high-speed electron transfer from MoS2 to Fe3+ and accelerating the Fe2+ regeneration; (b) the generated Fe0 serving as an excellent electron donor to jointly promote Fe3+/Fe2+ redox cycle. This study provides a simple way to establish architecture for synergistically promoting PMS-mediated degradation.

[Research progress on the role of resveratrol in wound healing]

The difficulty of wound healing in patients is a difficult problem that doctors in all clinical departments may encounter, and there is still no good solution. Resveratrol is a kind of natural active substance, which has anti-inflammatory, antioxidant, antibacterial, and angiogenesis promoting effects, and is a potential drug to promote wound healing. However, the clinical application of resveratrol is limited due to its low bioavailability. In this review, the molecular mechanism of resveratrol in promoting wound healing and its administration methods in wound treatment were reviewed to provide ideas for the redevelopment of resveratrol.

RSPSSL: A novel high-fidelity Raman spectral preprocessing scheme to enhance biomedical applications and chemical resolution visualization

Raman spectroscopy has tremendous potential for material analysis with its molecular fingerprinting capability in many branches of science and technology. It is also an emerging omics technique for metabolic profiling to shape precision medicine. However, precisely attributing vibration peaks coupled with specific environmental, instrumental, and specimen noise is problematic. Intelligent Raman spectral preprocessing to remove statistical bias noise and sample-related errors should provide a powerful tool for valuable information extraction. Here, we propose a novel Raman spectral preprocessing scheme based on self-supervised learning (RSPSSL) with high capacity and spectral fidelity. It can preprocess arbitrary Raman spectra without further training at a speed of ~1 900 spectra per second without human interference. The experimental data preprocessing trial demonstrated its excellent capacity and signal fidelity with an 88% reduction in root mean square error and a 60% reduction in infinite norm ([Formula: see text]) compared to established techniques. With this advantage, it remarkably enhanced various biomedical applications with a 400% accuracy elevation (ΔAUC) in cancer diagnosis, an average 38% (few-shot) and 242% accuracy improvement in paraquat concentration prediction, and unsealed the chemical resolution of biomedical hyperspectral images, especially in the spectral fingerprint region. It precisely preprocessed various Raman spectra from different spectroscopy devices, laboratories, and diverse applications. This scheme will enable biomedical mechanism screening with the label-free volumetric molecular imaging tool on organism and disease metabolomics profiling with a scenario of high throughput, cross-device, various analyte complexity, and diverse applications.

Self-supervised Self2Self denoising strategy for OCT speckle reduction with a single noisy image

Optical coherence tomography (OCT) inevitably suffers from the influence of speckles originating from multiple scattered photons owing to its low-coherence interferometry property. Although various deep learning schemes have been proposed for OCT despeckling, they typically suffer from the requirement for ground-truth images, which are difficult to collect in clinical practice. To alleviate the influences of speckles without requiring ground-truth images, this paper presents a self-supervised deep learning scheme, namely, Self2Self strategy (S2Snet), for OCT despeckling using a single noisy image. Specifically, in this study, the main deep learning architecture is the Self2Self network, with its partial convolution being updated with a gated convolution layer. Specifically, both the input images and their Bernoulli sampling instances are adopted as network input first, and then, a devised loss function is integrated into the network to remove the background noise. Finally, the denoised output is estimated using the average of multiple predicted outputs. Experiments with various OCT datasets are conducted to verify the effectiveness of the proposed S2Snet scheme. Results compared with those of the existing methods demonstrate that S2Snet not only outperforms those existing self-supervised deep learning methods but also achieves better performances than those non-deep learning ones in different cases. Specifically, S2Snet achieves an improvement of 3.41% and 2.37% for PSNR and SSIM, respectively, as compared to the original Self2Self network, while such improvements become 19.9% and 22.7% as compared with the well-known non-deep learning NWSR method.

Percutaneous Endoscopic Transforaminal Discectomy for the Treatment of Lumbar Disc Herniation with Different Migration Levels: A Retrospective Study

Objective

To investigate the surgical method and efficacy of percutaneous endoscopic transforaminal discectomy (PETD) for the treatment of lumbar disc herniation (LDH) with different migration levels by introducing the strategy of foramenoplasty with the "distal nucleus pulposus as the core".

Methods

Clinical data of LDH patients who underwent single-segment PETD surgery were retrospectively analyzed. Three groups were categorized according to the degree of nucleus pulposus migration in the sagittal position: no migration group, mild migration group, and high migration group. Different sites of foramenoplasty were used for LDH with different degrees of migration. All patients were followed up for at least 12 months. The clinical and follow-up data of the three groups were compared.

Results

A total of 102 patients were included, of which 46 (45.1%) were in the no migration group, 36 (35.3%) in the mild migration group, and 20 (19.6%) in the high migration group. Encouraging treatment results were obtained in all three groups.

Conclusion

PETD is effective in the treatment of LDH with different degrees of migration, and the foramenoplasty concept of "distal nucleus pulposus as the core" can effectively guide the molding site of foramenoplasty and facilitate the accurate placement of the working trocar.

[Research progress on HEG1 in cardiovascular generation and tumor development]

Heart development protein with EGF-like domains 1 (HEG1) is a novel mucin-like membrane protein with a long O-glycosylation region and EGF domain. HEG1 plays critical roles in embryo development and cardiogenesis, and is closely related to the occurrence and progression of malignant tumors. Here this article demonstrates the research progress on HEG1 in cardiovascular formation and tumor development in recent years, to inspire new ideas for the pathogenesis, diagnosis and treatment of related diseases.

Effect of public square dancing combined with serotonin reuptake inhibitors on persistent postural-perceptual dizziness (PPPD) in middle-aged and older women

BACKGROUND

Persistent postural-perceptual dizziness (PPPD) is a functional vestibular disorder that causes chronic dizziness and limits daily activities. Although pharmacology, vestibular rehabilitation, and cognitive behavioral therapy have been proposed to have some efficacy, they have certain limitations. Some patients with PPPD report that public square dancing can effectively relieve the symptoms of dizziness and instability, and their mood improves.

OBJECTIVE

To evaluate the effects of combining public square dancing with serotonin reuptake inhibitors (SSRIs/SNRIs) on the subjective sensations of dizziness, balance enhancement, anxiety, and depressive symptom regulation in middle-aged and older women with PPPD.

MATERIALS AND METHODS

In this trial, 124 patients diagnosed with PPPD were enrolled. Among them, 64 patients were randomly assigned to the experimental group (EG), where they received square dance training combined with serotonin reuptake inhibitors. The remaining 60 cases were randomly assigned to the control group (CG), where they received only serotonin reuptake inhibitors and did not participate in organized sports activities, allowing them freedom in their daily lives. Data from the Dizziness Handicap Inventory (DHI), Hospital Anxiety and Depression Scale (HADS), Active-specific Balance Confidence Scale (ABC), and Vestibular Disorder Activities of Daily Living Scale (VADL) were collected and compared at the beginning, 3 months, and 6 months of the trial to evaluate the effect of public square dancing on middle-aged and older women with PPPD.

RESULTS

There were no significant differences between the EG and CG before the trial. Compared with baseline measures, DHI, HADS, ABC, and VADL scores improved as the experiment progressed, and the improvements were more pronounced in the EG.

CONCLUSION

Public square dancing combined with serotonin reuptake inhibitors has a positive impact on the subjective sensations of dizziness, balance enhancement, anxiety, and depressive symptom regulation in middle-aged and older women with PPPD.

Artemisia baimaensis allelopathy has a negative effect on the establishment of Elymus nutans artificial grassland in natural grassland

Planting Elymus nutans artificial grassland to replace degraded Artemisia baimaensis grassland on the Qinghai Tibetan plateau (QTP) can effectively alleviate local grass-livestock imbalance. However, it is unknown whether the allelopathy of natural grassland plant A. baimaensis on E. nutans affects grassland establishment. Accordingly, we examined the effects of varying concentrations of aqueous extracts of A. baimaensis litter on the seed germination and early seedling growth of E. nutans, and the effects of A. baimaensis volatile organic compounds (VOCs) on the growth parameters and physiological characteristics of E. nutans. The results indicate that the aqueous extract inhibited the force, percentage, and index of germination of E. nutans and affected early seedling growth, particularly at high concentrations. Further, the VOCs significantly reduced the aboveground and root biomass of E. nutans and increased malondialdehyde concentrations. Additionally, these VOCs altered the antioxidant enzyme activities and increased the superoxide dismutase, peroxidase, ascorbic acid peroxidase, soluble sugar, and proline content but significantly decreased glutathione reductase levels. Our results indicate that the allelopathy of A. baimaensis significantly inhibited the germination and seedling growth of E. nutans . Thus, the leaching of A. baimaensis may produce allelochemicals in the soil that inhibit the germination of E. nutans seeds. Moreover, the VOCs of A. baimaensis may disrupt the growth process, resulting in a decrease in biomass and a disruption of the physiological metabolism of seedlings under field conditions.

Hepatic venous gas secondary to pulmonary barotrauma: rat model study

Intrahepatic gas (IHG) is commonly observed during early postmortem examinations of humans with upper or lower airway obstructions. We conducted a study to test the hypothesis that intrapulmonary gas could retrogradely spread to the hepatic vein following pulmonary barotrauma (PB). To establish a rat model of pulmonary barotrauma, we utilized a controllable pressure-vacuum pump to apply airway pressure (40, 60, or 80 mmHg). The rats were dissected directly at the end of the experiment, and histological analysis was performed through microscopic examination of the rats. Additionally, the rats were ventilated with meglumine diatrizoate under pressures of 160 and 250 mmHg to observe the signal dynamic diffusion using X-ray fluoroscopy examination. Rats exhibited classical changes associated with PB, such as alveolar rupture, pulmonary interstitial emphysema, and hemorrhage, as well as IHG characterized by the presence of gas in the hepatic vein and hepatic sinusoids. Air emboli were not observed in the liver in any of the 40 mmHg groups. However, they were observed in the liver in the 60 and 80 mmHg groups, the amount and size of air emboli in the 80 mmHg group were greater than those in the 60 mmHg group (p < 0.05). The 80 mmHg group presented radial grape-like bubbles in the centrilobular portion of the liver accompanied by congestion in the peripheral region of the hepatic lobule. X-ray fluoroscopy examination revealed a gradual enhancement of dynamic contrast medium signals from the lung to the inferior vena cava and then to the liver. Our findings indicate that pulmonary barotrauma can lead to the retrograde spread of intrapulmonary gas to the hepatic vein. When it is clear that no decomposition of the body has occurred, the presence of IHG serves as a novel indicator for the diagnosis of obstructive pulmonary disease or obstruction in the upper or lower airway.

NOVEL HIGH-STRENGTH POLYESTER COMPOSITE SCAFFOLDS FOR BONE REGENERATION

Repair of critical sized bone defects, particularly in load-bearing areas, is a major clinical problem that requires surgical intervention and implantation of biological or engineered grafts. For load-bearing sites, it is essential to use engineered grafts that have both sufficient mechanical strength and appropriate pore properties to support bone repair and tissue regeneration. Unfortunately, the mechanical properties of such grafts are often compromised due to the creation of pores required to facilitate tissue ingrowth following implantation. To overcome the limitations associated with porous scaffolds and their reduced mechanical strength, we have developed a methodology for creating a solid structure that retains its bulk mechanical properties while also evolving into a porous structure in a biological environment through degradation and erosion. In this study, we utilized polyesters that have been approved by the FDA, including poly (lactic acid) (PLA), poly(glycolic acid) (PGA), their copolymer PLGA (PLGA, with a ratio of 85:15 and 50:50 of PLA:PGA), and poly(caprolactone) (PCL). These polymers and their ceramic composites with tricalcium phosphate (TCP) were compression molded into solid forms, which exhibited mechanical properties with compressive modulus as high as 2745 ± 364 MPa within the range of human trabecular bone and in the lower range of human cortical bone. The use of fast-degrading PLGA (50:50) and PGA as porogens allowed the formation of pores within the solid structures due to their degradation, and the TCP acts as a buffering agent to neutralize their acidic degradation byproducts. These scaffolds facilitated the growth of new blood vessels and tissue ingrowth in a subcutaneous implantation model. In addition, in a rat critical-sized mandibular bone defects these scaffolds supported bone growth with 70% of new bone volume fraction. Furthermore, the extent of bone regeneration was found to be higher for the scaffolds with bone morphogenic proteins (BMP2), indicating their suitability for bone repair and regeneration.

Ipsilateral femoral neck, intertrochanteric and acetabular fractures with posterior dislocation of the hip: A case report and literature review

INTRODUCTION

Traumatic hip dislocation with ipsilateral femoral neck fracture, intertrochanteric fracture and acetabular fracture is a rare and serious injury that occurs mostly in young patients and after high-energy trauma. The treatment of these injuries is a major challenge for orthopedic surgeons; it can have devastating consequences if not treated properly, including avascular necrosis of the femoral head and traumatic osteoarthritis of the hip. In previous case reports only internal fixation of femoral neck fracture was performed without revascularisation and there was a lack of long-term follow-up results. In this report, we fixed the fracture revascularised the patient, and obtained good prognostic results at up to 20 months of follow-up.

CASE PRESENTATION

Here, we report an 18-year-old patient with systemic polytrauma resulting from a car accident. The trauma included ipsilateral posterior hip dislocation, acetabular fracture, femoral intertrochanteric fracture, and femoral neck fracture. In addition, the patient also had an ipsilateral open tibiofibula fracture. We chose the surgical treatment of a proximal femoral locking compression plate (PFLCP), femoral quadratus bone flap graft, and cannulated compression screw to treat the proximal femoral fracture. The patient was followed up for nearly 20 months; the range of motion of his hip was close to normal, and his hip function was good.

DISCUSSION AND CONCLUSIONS

Traumatic hip dislocation with ipsilateral femoral neck fracture, intertrochanteric fracture and acetabular fracture is a rare and serious injury, and surgical intervention is often needed. Because of the high risk of femoral head necrosis in such complex injuries, it is very important to protect/restore the blood supply of the femoral head during surgery. Therefore, in younger patients, we believe that the use of a quadratus femoris bone flap graft and PFLCP is an acceptable treatment for this severe injury. We discuss the management of this rare case and review the current literature to provide the best evidence-based recommendations for this injury pattern. We conclude that for patients with complex ipsilateral proximal femoral and acetabular fractures combined with hip dislocation, the key to surgical treatment, in addition to anatomic reduction and good fixation, is the primary reconstruction of the femoral head blood supply.

Construction and validation of a immune-related prognostic gene DHRS1 in hepatocellular carcinoma based on bioinformatic analysis

A member of the short-chain dehydrogenase/reductase superfamily (DHRS1, SDR19C1) is a member of the short-chain dehydrogenase/reductase superfamily and a potential predictor of hepatocellular carcinoma (HCC). However, the role of DHRS1 in HCC immunity remains unclear. We systematically analyzed the association between DHRS1 and HCC immunity with transcriptional and clinical data from the Tumor Immune Estimation Resource, an integrated repository portal for tumor immune system interactions, and cBioPortal databases. Six DHRS1-associated immunomodulators strongly correlated with survival and were uncovered by exploiting univariate and multivariate Cox analyses. We created a risk score for each patient by adding the points from each immunomodulator and then classified them into high and low risk categories. Survival analysis were used to compare the overall survival between the 2 groups, and the receiver operating characteristic curve was applied to assess the accuracy of the risk score. Data from our center were adopted as the external validation set, the risk score was calculated using the risk coefficient of the 6 genes in the training cohort, and survival analysis were executed to verify the experimental group results. A nomogram was ultimately constructed with the R package. Our data revealed a correlation between the levels of immune cell infiltration and either the DHRS1 gene copy numbers or mRNA levels in HCC. Second, we generated a signature based on the 6 DHRS1-related immunomodulators (KDR, TNFRSF4, CD276, TNFSF4, SLAMF6, and SIGLEC9). We postulate that the generated risk scores would serve as an independent indicator of HCC prognosis, with an area under the receiver operating characteristic curve for the risk score of 0.743. We further established external validation sets to reconfirm the predictive validity of the risk score. Finally, a prognostic nomogram and calibration curve were created. The DHRS1 gene may exert an impact on HCC immunity. We posit that the nominated immune signature based on DHRS1-associated immunomodulators could constitute a promising prognostic biomarker in HCC.

Responses of community traits and soil characteristics of Achnatherum inebrians-type degraded grassland to grazing systems in alpine meadows on the Qinghai-Tibet Plateau

Introduction

Scientific grazing management is of great significance for the ecological health and sustainable use of alpine meadows.

Methods

To explore appropriate management methods of alpine grasslands of the Qinghai-Tibet Plateau degraded by Achnatherum inebrians (Hance) Keng ex Tzvele presence, we studied the effects of different grazing systems on the A. inebrians population, grassland vegetation community traits, soil characteristics and soil microbial community structure for cold- season grazing plus supplementary feeding pasture (CSF) and four-season open public pasture (FOP) in Tianzhu County, Gansu Province.

Results

Compared with FOP, the CSF site showed significantly inhibited reproduction of A. inebrians, especially the crown width, seed yield and number of reproductive branches per plant were as high as 50%, significantly increased the aboveground biomass of edible forage and soil water content by 57% and 43-55%, better soil nutrients, and significantly reduced soil bulk density by 10- 29%. Different grazing systems affected the composition and diversity of soil microbial communities, with a greater effect on fungi than on bacterial flora. The most abundant phyla of bacteria and fungi were Proteobacteria and Ascomycota for CSF (by 30-38% and 24-28%) and for FOP (by 67-70% and 68-73%), and the relative abundance and species of bacterial and fungal genera were greater for CSF than FOP. The α-diversity indexes of fungi were improved, and the β-diversity of fungi was significant difference between CSF and FOP. However, the grazing utilization time was prolonged in FOP, which reduced the diversity and abundance of soil bacteria and increased soil spatial heterogeneity. The use of A. inebrians-type degraded grassland in the cold season, and as a winter supplementary feeding and resting ground, could effectively inhibit expansion of A. inebrians, promote edible forage growth, enhance grassland productivity and community stability, and improve soil structure.

Discussion

The results guide healthy and sustainable utilization of A. inebrians-type degraded grassland in the Qinghai-Tibet Plateau.

Loss-balanced parallel decoding network for retinal fluid segmentation in OCT

As a leading cause of blindness worldwide, macular edema (ME) is mainly determined by sub-retinal fluid (SRF), intraretinal fluid (IRF), and pigment epithelial detachment (PED) accumulation, and therefore, the characterization of SRF, IRF, and PED, which is also known as ME segmentation, has become a crucial issue in ophthalmology. Due to the subjective and time-consuming nature of ME segmentation in retinal optical coherence tomography (OCT) images, automatic computer-aided systems are highly desired in clinical practice. This paper proposes a novel loss-balanced parallel decoding network, namely PadNet, for ME segmentation. Specifically, PadNet mainly consists of an encoder and three parallel decoder modules, which serve as segmentation, contour, and diffusion branches, and they are employed to extract the ME's characteristics, the contour area features, and to expand the ME area from the center to edge, respectively. A new loss-balanced joint-loss function with three components corresponding to each of the three parallel decoding branches is also devised for training. Experiments are conducted with three public datasets to verify the effectiveness of PadNet, and the performances of PadNet are compared with those of five state-of-the-art methods. Results show that PadNet improves ME segmentation accuracy by 8.1%, 11.1%, 0.6%, 1.4% and 8.3%, as compared with UNet, sASPP, MsTGANet, YNet, RetiFluidNet, respectively, which convincingly demonstrates that the proposed PadNet is robust and effective in ME segmentation in different cases.

Rutaecarpine ameliorates osteoarthritis by inhibiting PI3K/AKT/NF‑κB and MAPK signalling transduction through integrin αVβ3

Osteoarthritis (OA) is a chronic progressive articular illness which commonly affects older‑aged adults, presenting with cartilage inflammation and degradation. Rutaecarpine (RUT) has been shown to exert promising anti‑inflammatory effects; however, the efficacy of RUT in the treatment of OA is debatable. The present study investigated the potential of RUT in alleviating OA in a mouse model. Treatment with RUT inhibited the inflammatory response and extracellular matrix degradation by suppressing process regulators in interleukin (IL)‑1β‑stimulated chondrocytes. Moreover, treatment with RUT in vitro upregulated the gene expression of anabolic agents, such as collagen type II, aggrecan and SRY‑box transcription factor 9, indicating that RUT contributed to cartilage repair. Additionally, flow cytometric assays, and the measurement of β‑galactosidase levels, autophagic flux and related protein expression revealed that RUT effectively attenuated IL‑1β‑induced chondrocyte apoptosis, senescence and autophagy impairment. In addition, bioinformatics analysis and in vitro experiments demonstrated that RUT protected cartilage by mediating the phosphoinositide‑3‑kinase (PI3K)/Akt/nuclear factor‑κB (NF‑κB) and mitogen‑activated protein kinase (MAPK) pathways. The ameliorative effects of RUT on IL‑1β‑stimulated chondrocytes were abrogated when siRNA was used to knock down integrin αVβ3. Furthermore, the results of immunohistochemical analysis and microcomputed tomography confirmed the in vivo therapeutic effects of RUT in mice with OA. On the whole, the present study demonstrates that RUT attenuates the inflammatory response and cartilage degradation in mice with OA by suppressing the activation of the PI3K/AKT/NF‑κB and MAPK pathways. Integrin αVβ3 may play a pivotal role in these effects.

Atypical primary central nervous system lymphoma and glioblastoma: multiparametric differentiation based on non-enhancing volume, apparent diffusion coefficient, and arterial spin labeling

OBJECTIVES

To evaluate the multiparametric diagnostic performance with non-enhancing tumor volume, apparent diffusion coefficient (ADC), and arterial spin labeling (ASL) to differentiate between atypical primary central nervous system lymphoma (PCNSL) and glioblastoma (GBM).

METHODS

One hundred and fifty-eight patients with pathologically confirmed typical PCNSL (n = 59), atypical PCNSL (hemorrhage, necrosis, or heterogeneous contrast enhancement, n = 29), and GBM (n = 70) were selected. Relative minimum ADC (rADCmin), mean (rADCmean), maximum (rADCmax), and rADCmax-min (rADCdif) were obtained by standardization of the contralateral white matter. Maximum cerebral blood flow (CBFmax) was obtained according to the ASL-CBF map. The regions of interests (ROIs) were manually delineated on the inner side of the tumor to further generate a 3D-ROI and obtain the non-enhancing tumor (nET) volume. The area under the curve (AUC) was used to evaluate the diagnostic performance.

RESULTS

Atypical PCNSLs showed significantly lower rADCmax, rADCmean, and rADCdif than that of GBMs. GBMs showed significantly higher CBFmax and nET volume ratios than that of atypical PCNSLs. Combined three-variable models with rADCmean, CBFmax, and nET volume ratio were superior to one- and two-variable models. The AUC of the three-variable model was 0.96, and the sensitivity and specificity were 90% and 96.55%, respectively.

CONCLUSION

The combined evaluation of rADCmean, CBFmax, and nET volume allowed for reliable differentiation between atypical PCNSL and GBM.

KEY POINTS

• Atypical PCNSL is easily misdiagnosed as glioblastoma, which leads to unnecessary surgical resection. • The nET volume, ADC, and ASL-derived parameter (CBF) were lower for atypical PCNSL than that for glioblastoma. • The combination of multiple parameters performed well (AUC = 0.96) in the discrimination between atypical PCNSL and glioblastoma.

Age-related decline in hippocampal tyrosine phosphatase PTPRO is a mechanistic factor in chemotherapy-related cognitive impairment

Chemotherapy-related cognitive impairment (CRCI) or "chemo brain" is a devastating neurotoxic sequela of cancer-related treatments, especially for the elderly individuals. Here we show that PTPRO, a tyrosine phosphatase, is highly enriched in the hippocampus, and its level is tightly associated with neurocognitive function but declined significantly during aging. To understand the protective role of PTPRO in CRCI, a mouse model was generated by treating Ptpro-/- female mice with doxorubicin (DOX) because Ptpro-/- female mice are more vulnerable to DOX, showing cognitive impairments and neurodegeneration. By analyzing PTPRO substrates that are neurocognition-associated tyrosine kinases, we found that SRC and EPHA4 are highly phosphorylated/activated in the hippocampi of Ptpro-/- female mice, with increased sensitivity to DOX-induced CRCI. On the other hand, restoration of PTPRO in the hippocampal CA3 region significantly ameliorate CRCI in Ptpro-/- female mice. In addition, we found that the plant alkaloid berberine (BBR) is capable of ameliorating CRCI in aged female mice by upregulating hippocampal PTPRO. Mechanistically, BBR upregulates PTPRO by downregulating miR-25-3p, which directly targeted PTPRO. These findings collectively demonstrate the protective role of hippocampal PTPRO against CRCI.

Decorin: a potential therapeutic candidate for ligamentum flavum hypertrophy by antagonizing TGF-β1

Ligamentum flavum hypertrophy (LFH) is the main physiological and pathological mechanism of lumbar spinal canal stenosis (LSCS). The specific mechanism for LFH has not been completely clarified. In this study, bioinformatic analysis, human ligamentum flavum (LF) tissues collection and analysis, and in vitro and in vivo experiments were conducted to explore the effect of decorin (DCN) on LFH pathogenesis. Here, we found that TGF-β1, collagen I, collagen III, α-SMA and fibronectin were significantly upregulated in hypertrophic LF samples. The DCN protein expression in hypertrophic LF samples was higher than that in non-LFH samples, but the difference was not significant. DCN inhibited the expression of TGF-β1-induced fibrosis-associated proteins in human LF cells, including collagen I, collagen III, α-SMA, and fibronectin. ELISAs showed that TGF-β1 can upregulate PINP and PIIINP in the cell supernatant, and this effect was inhibited after DCN administration. Mechanistic studies revealed that DCN suppressed TGF-β1-induced fibrosis by blocking the TGF-β1/SMAD3 signaling pathway. In addition, DCN ameliorated mechanical stress-induced LFH in vivo. In summary, our findings indicated that DCN ameliorated mechanical stress-induced LFH by antagonizing the TGF-β1/SMAD3 signaling pathway in vitro and in vivo. These findings imply that DCN is a potential therapeutic candidate for ligamentum flavum hypertrophy.

[Progress and reflection of conversion therapy for locally advanced pancreatic cancer]

With the improvement of nonsurgical treatment in pancreatic cancer, the increasing accuracy of subclassification of anatomy, and the continuous refinement of surgical resection techniques, more and more locally advanced pancreatic cancer(LAPC) patients have the opportunity to undergo conversion surgery and achieve survival benefits,which has attracted the attention of scholars in this field. Despite the numerous prospective clinical studies conducted, there is still a lack of high-level evidence-based medical evidence in terms of conversion treatment strategies, efficacy evaluation, surgical timing and survival prognosis, and there are not yet specific quantitative standards and guiding principles for conversion treatment for these patients in clinical practice, and the indications for surgical resection rely more on the experience of each center or surgeon, lacking consistency. Therefore,the indicators for the evaluation of the efficacy of conversion treatment in patients with LAPC were summarized to reflect on the different modes of conversion treatment and clinical outcomes currently being explored, expecting to provide more accurate recommendations and guidance for the clinic.

Fabrication and Evaluation of Porous dECM/PCL Scaffolds for Bone Tissue Engineering

Porous scaffolds play a crucial role in bone tissue regeneration and have been extensively investigated in this field. By incorporating a decellularized extracellular matrix (dECM) onto tissue-engineered scaffolds, bone regeneration can be enhanced by replicating the molecular complexity of native bone tissue. However, the exploration of porous scaffolds with anisotropic channels and the effects of dECM on these scaffolds for bone cells and mineral deposition remains limited. To address this gap, we developed a porous polycaprolactone (PCL) scaffold with anisotropic channels and functionalized it with dECM to capture the critical physicochemical properties of native bone tissue, promoting osteoblast cells' proliferation, differentiation, biomineralization, and osteogenesis. Our results demonstrated the successful fabrication of porous dECM/PCL scaffolds with multiple channel sizes for bone regeneration. The incorporation of 100 μm grid-based channels facilitated improved nutrient and oxygen infiltration, while the porous structure created using 30 mg/mL of sodium chloride significantly enhanced the cells' attachment and proliferation. Notably, the mechanical properties of the scaffolds closely resembled those of human bone tissue. Furthermore, compared with pure PCL scaffolds, the presence of dECM on the scaffolds substantially enhanced the proliferation and differentiation of bone marrow stem cells. Moreover, dECM significantly increased mineral deposition on the scaffold. Overall, the dECM/PCL scaffold holds significant potential as an alternative bone graft substitute for repairing bone injuries.

Pipkin type III femoral head fracture: which treatment strategy can be recommended?

BACKGROUND

Pipkin type III femoral head fractures are relatively rare injuries. Few studies have explored and described the treatment and outcomes of Pipkin type III femoral head fractures. The purpose of this study was to evaluate the efficacy of open reduction and internal fixation (ORIF) in treating Pipkin type III femoral head fractures.

METHODS

We retrospectively reviewed 12 patients with Pipkin type III femoral head fractures who underwent ORIF from July 2010 and January 2018. The complications and reoperations were recorded. The visual analog scale (VAS) pain score, Harris hip score (HHS), Thompson-Epstein criteria, and SF-12 score [including the physical component summary (PCS) and the mental component summary (MCS)] were used for functional assessment.

RESULTS

Among the 12 patients, ten were males and two were females, with a mean age of 34.2 ± 11.9 years. The median follow-up time was 6 years (range 4-8 years). Five patients (42%) developed osteonecrosis of the femoral head, and one patient (8%) developed nonunion. These six patients (50%) underwent total hip arthroplasty (THA). One patient (8%) developed heterotopic ossification and underwent ectopic bone excision; this patient also presented with post-traumatic arthritis. The mean final VAS pain score and HHS were 4.1 ± 3.1 points and 62.8 ± 24.4 points, respectively. According to the Thompson-Epstein criteria, there was one patient (8%) with excellent, four patients (33%) with good, one patient (8%) with fair, and six patients (50%) with poor outcomes. The PCS score and MCS score were 41.7 ± 34.7 points and 63.2 ± 14.5 points, respectively.

CONCLUSION

Limited by the high incidence of osteonecrosis of the femoral head, it is difficult to achieve satisfactory functional outcomes when treating Pipkin type III femoral head fractures using ORIF, and a primary THA may be considered. However, for younger patients, considering the survivorship of prosthesis, ORIF may be recommended with the proviso that the patient is fully informed of the high complication rate associated with this procedure.

LEVEL OF EVIDENCE

IV.

[Population structure of food-borne Staphylococcus aureus in China]

Objective: To understand the population structure of food-borne Staphylococcus (S.) aureus in China. Methods: Whole genome sequencing was used to analyze 763 food-borne S. aureus strains from 16 provinces in China from 2006 to 2020. Multilocus sequence typing (MLST), staphylococcal protein A gene (spa) typing, and staphylococcal chromosome cassettemec (SCCmec) typing were conducted, and minimum spanning tree based on ST types (STs) was constructed by BioNumerics 7.5 software. Thirty-one S. aureus strains isolated from imported food products were also included in constructing the genome phylogenetic tree. Results: A total of 90 STs (20 novel types) and 160 spa types were detected in the 763 S. aureus isolates. The 72 STs (72/90, 80.0%) were related to 22 clone complexes. The predominant clone complexes were CC7, CC1, CC5, CC398, CC188, CC59, CC6, CC88, CC15, and CC25, accounting for 82.44% (629/763) of the total. The STs and spa types in the predominant clone complexes changed over the years. The methicillin-resistant S. aureus (MRSA) detection rate was 7.60%, and 7 SCCmec types were identified. The ST59-t437-Ⅳa (17.24%, 10/58), ST239-t030-Ⅲ (12.07%, 7/58), ST59-t437-Ⅴb (8.62%, 5/58), ST338-t437-Ⅴb (6.90%, 4/58) and ST338-t441-Ⅴb (6.90%, 4/58) were the main types in MRSA strains. The genome phylogenetic tree had two clades, and the strains with the same CC, ST, and spa types clustered together. All CC7 methicillin sensitive S. aureus strains were included in Clade1, while 21 clone complexes and all MRSA strains were in Clade2. The MRSA strains clustered according to the SCCmec and STs. The strains from imported food products in CC398, CC7, CC30, CC12, and CC188 had far distances from Chinese strains in the tree. Conclusions: In this study, the predominant clone complexes of food-borne strains were CC7, CC1, CC5, CC398, CC188, CC59, CC6, CC88, CC15, and CC25, which overlapped with the previously reported clone complexes of hospital and community-associated strains in China, suggesting that close attention needs to be paid to food, a vehicle of pathogen transmission in community and food poisoning.

[Study of the urban-impact on microbial communities and their virulence factors and antibiotic resistance genomes in the Nandu River, Haikou]

Objective: To explore the changes in bacterial community structure, antibiotic resistance genome, and pathogen virulence genome in river water before and after the river flowing through Haikou City and their transmission and dispersal patterns and to reveal anthropogenic disturbance's effects on microorganisms and resistance genes in the aquatic environment. Methods: The Nandu River was divided into three study areas: the front, middle and rear sections from the upstream before it flowed through Haikou City to the estuary. Three sampling sites were selected in each area, and six copies of the sample were collected in parallel at each site and mixed for 3 L per sample. Microbial community structure, antibiotic resistance, virulence factors, and mobile genetic elements were analyzed through bioinformatic data obtained by metagenomic sequencing and full-length sequencing of 16S rRNA genes. Variations in the distribution of bacterial communities between samples and correlation of transmission patterns were analyzed by principal co-ordinates analysis, procrustes analysis, and Mantel test. Results: As the river flowed through Haikou City, microbes' alpha diversity gradually decreased. Among them, Proteobacteria dominates in the bacterial community in the front, middle, and rear sections, and the relative abundance of Proteobacteria in the middle and rear sections was higher than that in the front segment. The diversity and abundance of antibiotic resistance genes, virulence factors, and mobile genetic elements were all at low levels in the front section and all increased significantly after flow through Haikou City. At the same time, horizontal transmission mediated by mobile genetic elements played a more significant role in the spread of antibiotic-resistance genes and virulence factors. Conclusions: Urbanization significantly impacts river bacteria and the resistance genes, virulence factors, and mobile genetic elements they carry. The Nandu River in Haikou flows through the city, receiving antibiotic-resistant and pathogen-associated bacteria excreted by the population. In contrast, antibiotic-resistant genes and virulence factors are enriched in bacteria, which indicates a threat to environmental health and public health. Comparison of river microbiomes and antibiotic resistance genomes before and after flow through cities is a valuable early warning indicator for monitoring the spread of antibiotic resistance.

Self-supervised Blind2Unblind deep learning scheme for OCT speckle reductions

As a low-coherence interferometry-based imaging modality, optical coherence tomography (OCT) inevitably suffers from the influence of speckles originating from multiply scattered photons. Speckles hide tissue microstructures and degrade the accuracy of disease diagnoses, which thus hinder OCT clinical applications. Various methods have been proposed to address such an issue, yet they suffer either from the heavy computational load, or the lack of high-quality clean images prior, or both. In this paper, a novel self-supervised deep learning scheme, namely, Blind2Unblind network with refinement strategy (B2Unet), is proposed for OCT speckle reduction with a single noisy image only. Specifically, the overall B2Unet network architecture is presented first, and then, a global-aware mask mapper together with a loss function are devised to improve image perception and optimize sampled mask mapper blind spots, respectively. To make the blind spots visible to B2Unet, a new re-visible loss is also designed, and its convergence is discussed with the speckle properties being considered. Extensive experiments with different OCT image datasets are finally conducted to compare B2Unet with those state-of-the-art existing methods. Both qualitative and quantitative results convincingly demonstrate that B2Unet outperforms the state-of-the-art model-based and fully supervised deep-learning methods, and it is robust and capable of effectively suppressing speckles while preserving the important tissue micro-structures in OCT images in different cases.

High level of tumor marker CA19-9 returned to normal after cholecystectomy in calculous cholecystitis patients

BACKGROUND

High serum CA19-9 is usually caused by pancreaticobiliary malignancies, but it has also been found in a tiny minority of calculous cholecystitis patients.

AIMS

To clarify the relationship between calculous cholecystitis and serum CA19-9.

METHODS

Clinical data of calculous cholecystitis patients with high serum CA19-9 (high group, n = 20) and normal serum CA19-9 (normal group, n = 40) who underwent cholecystectomy were analyzed. Serum CA19-9 of high group were followed-up and gallbladder specimens were analyzed by immunohistochemistry.

RESULTS

Serum CA19-9 in the high group ranged from 105 to 1635 U/ml, of which 30% exceeded 1000 U/ml. Follow-up results showed that 20 patient's serum CA19-9 returned to normal after cholecystectomy, including 4 closely followed-up patients whose serum CA19-9 recovered within one month. Immunohistochemical results revealed that CA19-9 was mildly positive only in mucosal epithelial cells in the normal group, but positive in mucosal epithelial cells, vascular endothelial cells, and intercellular substances in the high group, accounting for high serum CA19-9.

CONCLUSION

Serum CA19-9 is proved to be associated with calculous cholecystitis for the first time, so that clinicians should consider calculous cholecystitis associated CA19-9 elevation in the clinic practice besides other CA19-9 related diseases.

A comprehensive analysis of single-cell RNA transcriptome reveals unique SPP1+ chondrocytes in human osteoarthritis

Osteoarthritis (OA) has become the most common degenerative disease in the world, which brings a serious economic burden to society and the country. Although epidemiological studies have shown that the occurrence of osteoarthritis is associated with obesity, sex, and trauma, the biomolecular mechanisms for the development and progression of osteoarthritis remain ambiguous. Several studies have drawn a connection between SPP1 and osteoarthritis. SPP1 was first found to be highly expressed in osteoarthritic cartilage, and later more studies have shown that SPP1 is also highly expressed in subchondral bone and synovial in OA patients. However, the biological function of SPP1 remains unclear. Single-cell RNA sequencing (scRNA-seq) is a novel technique that reflects gene expression at the cellular level, making it better depict the state of different cells than ordinary transcriptome data. However, most of the existing chondrocyte scRNA-seq studies focus on the occurrence and development of OA chondrocytes and lack analysis of normal chondrocyte development. Therefore, to better understand the mechanism of OA, scRNA-seq analysis of a larger cell volume containing normal and osteoarthritic cartilage is of great importance. Our study identifies a unique cluster of chondrocytes characterized by high SPP1 expression. The metabolic and biological characteristics of these clusters were further investigated. Besides, in animal models, we found that the expression of SPP1 is spatially heterogeneous in cartilage. Overall, our work provides novel insight into the potential role of SPP1 in OA, which sheds light on understanding the role of SPP1 in OA, promoting the progress of the treatment and prevention in the field of OA.

Is Ankle Arthrodesis With an Ilizarov External Fixator an Effective Treatment for Septic Ankle Arthritis? A Study With a Minimum of 6 Years of Follow-up

BACKGROUND

Septic ankle arthritis is a devastating clinical problem with a high potential for permanent disability and amputation. Successful treatment of septic ankle arthritis remains a challenge for the surgeon and patient. Ankle arthrodesis combined with radical debridement may be an effective option to eradicate infection and salvage the limb. Although numerous fusion methods have been proposed, there is controversy about the most effective technique.

QUESTIONS/PURPOSES

At a minimum follow-up of 6 years after ankle arthrodesis performed using an Ilizarov external fixator, we asked, (1) In what proportion of patients was bony fusion achieved? (2) What complications were observed, and what reoperations were performed in these patients? (3) How much did patient-reported outcomes improve from before surgery to the most recent follow-up in this group?

METHODS

Between April 2010 to March 2015, we treated 59 patients for septic ankle arthritis. Of those, we considered patients who were at least 18 years of age with irreversible destruction of the joint as potentially eligible. During that time period, all patients met the prespecified criteria and were treated with ankle arthrodesis using an Ilizarov external fixator. Two percent (one of 59) of patients were excluded because they died in the second year after surgery for reasons unrelated to the procedure, and another 7% (four of 59) of patients were excluded because they were lost before the minimum study follow-up interval of 6 years. Finally, 92% (54 of 59) of patients were analyzed at a mean follow-up time of 9 ± 1 years. A total of 61% (33 of 54) were men, and they had a mean age of 48 ± 12 years. Forty-six percent (25 of 54) of patients were smokers, and 13% (seven of 54) of patients had Type 2 diabetes mellitus. All patients received radical debridement and primary arthrodesis with an Ilizarov external fixator, followed by antibiotic therapy. Postoperatively, patients were instructed to perform lower extremity functional exercises and external fixator care; weightbearing ambulation as tolerated was encouraged as early as possible. Fusion was assessed with a radiographic review that was performed by an individual who was not involved in the surgical care of these patients. We defined bony fusion as continuous trabeculae and complete cortical bridging in the fusion interface achieved before 9 months; delayed union was defined as fusion achieved by 9 to 12 months; and nonunion was defined as patients in whom fusion was not achieved by 12 months. Complications and reoperations were tallied through a record review that was performed by an individual who was not involved in the surgical care of these patients. We defined complications as any deviation from the expected postoperative course. We used the American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, the VAS active pain score, and the SF-12 questionnaire (including the physical component summary [PCS] score and mental component summary [MCS] score) to assess patient-reported outcomes. The minimum clinically important difference (MCID) for the AOFAS score was 30 points of 100, the MCID for the VAS active pain score was 2 points of 10, and the MCID of PCS and MCS scores was 7 points and 9 points, respectively.

RESULTS

Primary bony fusion was achieved in 94% (51 of 54) of patients. Delayed union was found in 2% (one of 54) of patients. Nonunion was found in 6% (three of 54); one of these patients underwent autologous bone grafting during revision, and bony fusion was ultimately achieved. Final bony fusion was achieved in 96% (52 of 54) of patients. Recurrent infection was found in 2% (one of 54). The median (range) AOFAS score improved from 28 points (8 to 59) before surgery to 80 points (52 to 86) at the most recent follow-up (median difference 52; p < 0.001). The median (range) VAS active pain score decreased from 8 points (6 to 9) before surgery to 2 points (0 to 5) at the most recent follow-up (median difference -6; p < 0.001). For the Short Form 12-item score, the median (range) PCS score improved from 0 points (0 to 30) before surgery to 70 points (40 to 95) at the most recent follow-up (median difference 70; p < 0.001), and the median (range) MCS score improved from 46 points (21 to 75) before surgery to 75 points (50 to 92) at the most recent follow-up (median difference 29; p < 0.001).

CONCLUSION

Ankle arthrodesis with Ilizarov external fixation might eradicate an infection and restore foot function in patients with septic ankle arthritis. However, patients should be fully informed of the complications related to the external fixator, such as pin-tract infections, recurrent infection, and nonunion. Standardized and professional pin care is important. Additionally, because Ilizarov external fixators can be inconvenient to the patients' daily lives, future studies should explore how psychologic support affects patients who undergo ankle arthrodesis with these devices.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Multiscale denoising generative adversarial network for speckle reduction in optical coherence tomography images

Purpose

Optical coherence tomography (OCT) is a noninvasive, high-resolution imaging modality capable of providing both cross-sectional and three-dimensional images of tissue microstructures. Owing to its low-coherence interferometry nature, however, OCT inevitably suffers from speckles, which diminish image quality and mitigate the precise disease diagnoses, and therefore, despeckling mechanisms are highly desired to alleviate the influences of speckles on OCT images.

Approach

We propose a multiscale denoising generative adversarial network (MDGAN) for speckle reductions in OCT images. A cascade multiscale module is adopted as MDGAN basic block first to raise the network learning capability and take advantage of the multiscale context, and then a spatial attention mechanism is proposed to refine the denoised images. For enormous feature learning in OCT images, a deep back-projection layer is finally introduced to alternatively upscale and downscale the features map of MDGAN.

Results

Experiments with two different OCT image datasets are conducted to verify the effectiveness of the proposed MDGAN scheme. Results compared those of the state-of-the-art existing methods show that MDGAN is able to improve both peak-single-to-noise ratio and signal-to-noise ratio by 3 dB at most, with its structural similarity index measurement and contrast-to-noise ratio being 1.4% and 1.3% lower than those of the best existing methods.

Conclusions

Results demonstrate that MDGAN is effective and robust for OCT image speckle reductions and outperforms the best state-of-the-art denoising methods in different cases. It could help alleviate the influence of speckles in OCT images and improve OCT imaging-based diagnosis.

Different femoral tunnel placement in posterior cruciate ligament reconstruction: a finite element analysis

BACKGROUND

At present, there is no consensus on the optimal biomechanical method for Posterior cruciate ligament (PCL) reconstruction, and the "critical corner" that is produced by the femoral tunnel is currently considered to be one of the main reasons for PCL failure. Thus, the purpose of this study was to identify one or several different tunnels of the femur, thereby reducing the influence of the "critical corner" without reducing the posterior stability of the knee.

METHODS

CT and MRI data of the knee joint of a healthy adult man were collected, and computer-related software was used to reconstruct the finite element model of the knee joint, to provide different properties to different materials and to allow for the performance of a finite element analysis of the reconstructed model. The position of the femoral tunnel was positioned and partitioned according to anatomical posture, and three areas were divided (the antero-proximal region, the antero-distal region and the posterior region). In addition, we applied a posterior tibial load of 134 N to the reconstructed model, recorded and compared different tunnels of the femur, conducted peak stress at the flexion of the knee joint of 0°, 30°, 60° and 90°, and elicited the displacement of the proximal tibia.

RESULTS

Among the 20 different femoral tunnels, the graft peak stress was lower in tunnels 4, 12 and 18 than in the PCL anatomical footpath tunnel 13, especially at high flexion angles (60° and 90°). These three tunnels did not increase the posterior displacement of the proximal tibia compared with the anatomical footpath tunnel 13.

CONCLUSION

In summary, among the options for PCL reconstruction of the femoral tunnel, the tunnels located 5 mm distal to the footprint and 5 mm anterior to the footprint could reduce the peak stress of the graft; additionally, it may reduce the "critical corner" and was shown to not reduce the posterior stability of the knee joint.

Let-7c-5p down-regulates immune-related CDCA8 to inhibit hepatocellular carcinoma

OBJECTIVE

The aim of this study is to investigate the effect of let-7c-5p on the malignant behaviors of hepatocellular carcinoma (HCC) and its specific molecular pathway.

METHODS

Differential expression and survival analysis of let-7c-5p were obtained from The Cancer Genome Atlas database, and then its expression level was preliminarily verified through qPCR. The effect of let-7c-5p on the malignant phenotype of HCC cells was subsequently evaluated using CCK-8, transwell, wound healing, and flow cytometry assays. Downstream mRNA regulated by let-7c-5p was identified and confirmed by ENCORI database, dual-luciferase reporter, and western blot assays. The immunocorrelation of genes was evaluated by Xiantao tool, and TIMER and TISIDB databases.

RESULTS

The expression level of let-7c-5p in HCC was obviously reduced, which was found to be closely associated with the short survival time of HCC patients. Cell phenotypic experiments showed that let-7c-5p inhibited proliferation, invasion, and migration and promoted apoptosis of HCC cells. Dual-luciferase reporter and western blot analysis demonstrated that CDCA8 is a downstream mRNA of let-7c-5p and is negatively regulated by it. Rescue experiment revealed that CDCA8 reversed the effect of let-7c-5p on the malignant phenotype of HCC cells. Furthermore, analysis of the public database revealed that CDCA8 is related to some immune cells and immunomodulators, and that it may participate in the regulation of some immune pathways and immune functions.

CONCLUSION

Let-7c-5p has been proved to suppress HCC by down-regulating immune-related CDCA8, which will help understand the pathogenesis of HCC and develop drugs for its treatment.

Resistance and Molecular Characteristics of Methicillin-Resistant Staphylococcus aureus and Heterogeneous Vancomycin-Intermediate Staphylococcus aureus

Objective

To investigate the molecular epidemiology of Staphylococcus aureus (S. aureus) isolated from patients in the Yellow River Delta region and to construct antibiotic resistance profiles in different genetic backgrounds.

Methods

Antibiotics susceptibility testing, staphylococcal protein A (spa) typing and accessory gene regulator (agr) typing were performed for all the 204 strains. Isolates with the positive mecA gene and heterogeneous vancomycin-intermediate S. aureus (hVISA) were subjected to multilocus sequence typing (MLST) and Staphylococcal chromosomal cassettes mec (SCCmec) typing.

Results

Thirty-nine MRSA strains were identified by mecA gene. Twenty-two hVISA isolates including 9 MRSA and 13 methicillin-sensitive S. aureus (MSSA) strains were confirmed, the rest isolates (n = 182) were vancomycin-susceptible S. aureus (VSSA). 94.9% of MRSA and 63.6% of hVISA belonged to agrI. Fifty-seven distinct spa types including 5 novel types were mainly t309 (30.9%), t078 (11.8%) and t437 (11.8%). Fourteen sequence types (STs) containing 3 new STs were classified into 3 clone complexes (CCs) and 7 singletons among MRSA and hVISA isolates. Most MRSA isolates (87.2%) belonged to type Ⅳ SCCmec.

Conclusion

The predominant genotype among MRSA population was ST59-t437-agrI-IVa (53.8%), followed by ST72-t2431-agrI-IVF (15.4%). ST72 and CC5 (ST5/965/7197) were the most common hVISA clones. Both CC59 (ST59/7437) and ST72 clones were resistant to erythromycin and clindamycin among MRSA population. Strains of MSSA with phenotypic hVISA (MS-hVISA) exhibited a striking genetic diversity accompanied by the diversification of drug resistance patterns.

Is 3D-printed Titanium cage a reliable option for 3-level anterior cervical discectomy and fusion in treating degenerative cervical spondylosis?

Background

To assess the clinical and radiographical outcomes of 3-level anterior cervical discectomy and fusion (ACDF) with a 3D-printed titanium cage in treating degenerative cervical spondylosis.

Methods

In this study, 25 patients with degenerative cervical spondylosis who underwent 3-level ACDF using a 3D-printed titanium cage from March 2019 to June 2021 were retrospectively enrolled. The patient-reported outcome measures (PROMs) were evaluated by visual analog scale (VAS) for the neck (VAS-neck) and arm pain (VAS-arm), Neck Disability Index (NDI) score, Japanese Orthopedic Association (JOA) score, SF-12 concise health survey, and the Odom criteria. The radiographical parameters, including C2-C7 lordosis, segmental angle, segmental height, and subsidence, were assessed. The mean duration of follow-up was 25.6 months.

Results

Bony fusion was achieved in all patients (100%). In three patients (12%) mild dysphagia was observed during the follow-up. The VAS-neck, VAS-arm, NDI score, JOA score, SF-12 score, C2-C7 lordosis, and segmental angle improved noticeably at the latest follow-up. Based on the Odom criteria, 22 patients (88%) reported satisfactory (excellent or good). The mean loss of C2-C7 lordosis and segmental angle between the immediate postoperative and the latest follow-up values were 1.6° ± 0.5° and 1.1° ± 0.5°, respectively. The mean subsidence was 0.9 ± 0.6 mm.

Conclusion

In patients with multi-level degenerative cervical spondylosis, 3-level ACDF using the 3D-printed titanium cage can effectively relieve the symptoms, stabilize the spine, and restore segmental height and cervical curvature. It is proven to be a reliable option for patients with 3-level degenerative cervical spondylosis. However, a future comparative study involving a larger population and longer follow-up time may be required to further evaluate the safety, efficacy and outcomes of our preliminary results.

ECG classification using 1-D convolutional deep residual neural network

An electrocardiograph (ECG) is widely used in diagnosis and prediction of cardiovascular diseases (CVDs). The traditional ECG classification methods have complex signal processing phases that leads to expensive designs. This paper provides a deep learning (DL) based system that employs the convolutional neural networks (CNNs) for classification of ECG signals present in PhysioNet MIT-BIH Arrhythmia database. The proposed system implements 1-D convolutional deep residual neural network (ResNet) model that performs feature extraction by directly using the input heartbeats. We have used synthetic minority oversampling technique (SMOTE) that process class-imbalance problem in the training dataset and effectively classifies the five heartbeat types in the test dataset. The classifier's performance is evaluated with ten-fold cross validation (CV) using accuracy, precision, sensitivity, F1-score, and kappa. We have obtained an average accuracy of 98.63%, precision of 92.86%, sensitivity of 92.41%, and specificity of 99.06%. The average F1-score and Kappa obtained were 92.63% and 95.5% respectively. The study shows that proposed ResNet performs well with deep layers compared to other 1-D CNNs.

Effect of Pheretima aspergillum on reducing fibrosis: A systematic review and meta-analysis

Background: Pheretima aspergillum (common name: Earthworm, Chinese name: dilong) has been used in traditional Chinese medicine for thousands of years. Recently, a few scientific studies have investigated the antifibrotic effects of Dilong extract (DE) and produced controversial results. We conducted a meta-analysis to make an informed decision on the antifibrotic effects of Dilong extract. Methods: The studies on antifibrotic effects of Dilong extract published until July 2022 in the scientific databases [PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), VIP database for Chinese Technical Periodicals, SinoMed and WanFang database] were reviewed. The RevMan 5.4.1 software was used for standardized mean difference (SMD) analysis. Two researchers independently reviewed all the studies, and their quality was assessed using the Cochrane risk of bias tool. Results: A total of 325 studies were found in the scientific databases; however, only 13 studies met the criteria for analysis. Dilong extract treatment was associated with antifibrotic effects via inhibiting the transforming growth factor beta 1 (TGF-β1, SMD = -3.16, 95% CI: -4.18, -2.14, p < .00001) and alpha-smooth muscle actin (α-SMA: SMD = -2.57, 95% CI: -3.47, -1.66, p < .00001). Conclusion: Dilong extract effectively reduces tissue fibrosis; thus, further scientific studies should be conducted to investigate and develop it for clinical use. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42022357141.

Albumin-Coated Polycaprolactone (PCL)-Decellularized Extracellular Matrix (dECM) Scaffold for Bone Regeneration

With the emphasis on collagen and hydroxyapatite, the main structural components of bone tissue, synthetic grafts fall short of matching the clinical efficacy of autologous bone grafts. Excluded non-collagenous protein (NCPs) and carbohydrates also participate in critical cell signaling cascades and guide mineral deposition during intermediate stages of bone healing. By mimicking the native fracture repair process, polymeric scaffolds that incorporate calcium-binding moieties present in fibrocartilage can potentially enhance their bioactivity, mineralization, and bone growth. Likewise, coating polymeric fibers with serum albumin is an additional strategy that can impart collagen-like biofunctionality and further increase mineral deposition on the fibrous surface. Here, a combination of electrospun polycaprolactone (PCL) fibers with chondrocyte-derived decellularized extracellular matrix (dECM) and albumin coating were investigated as a fibrocartilage-mimetic scaffold that can serve as a woven bone precursor for bone regeneration. PCL fibrous constructs coated with dECM and albumin are shown to synergistically increase calcium concentration and calcium phosphate (CaP) deposition in a simulated body fluid biomineralization assay. Albumin/dECM coating increased osteoblast proliferation and mineral deposition in culture. In contrast, CaP coating transformed osteoblast bone lining morphology into cuboidal phenotype and arrested their proliferation. Cell sheets of osteoblasts cultured on dECM/albumin/CaP-coated constructs exhibited an increase in calcium deposition and secretion of collagen, osteopontin, osteocalcin, and bone morphogenetic protein. These results highlight the potential of biomolecular coatings to enhance bone-mimetic properties of synthetic nanofibrous scaffolds, stimulate critical protein and mineral deposition, and augment the bone's capacity to heal. Thus, mimicking the intermediate stages of bone regeneration by incorporating calcium-binding moieties may prove to be a useful strategy for improving the clinical outcomes of synthetic bone grafts.

[Risk assessment of Cronobacter sakazakii in infant formula powder]

Objective: To assess the risk of foodborne diseases caused by Cronobacter sakazakii in infant formula powder from retail to feeding and provide formulate suggestions for safe feeding of infants at home. Methods: This study used the special monitoring and risk monitoring data of infant formula powder in Heilongjiang Province and combined data at home and abroad. The @RISK software was used to evaluate the disease risk caused by Cronobacter sakazakii in the process of infant formula powder from retail to feeding. Results: According to the results of this quantitative risk assessment, the risk of foodborne diseases caused by Cronobacter sakazakii at the current consumption pattern in Heilongjiang Province was 5.158×10^-5 persons/million (40.0 ℃ and 50.0 ℃), 1.072×10^-7 persons/million (60.0 ℃), 5.544×10^-14 persons/million (70.0 ℃). When the feeding time of infant formula powder was adjusted to 0-2 h and 2-3 h respectively, the above prediction results did not change. When it was adjusted to 3-4 h, the risk increased. If it was adjusted to 4-24 h, the number of Cronobacter sakazakii increased by 14-24 orders of magnitude at room temperature. If the initial pollution concentration (after flushing) was adjusted to 1 MPN/ml, the average disease risk per meal was 805.7 persons/million (40.0 ℃ and 50.0 ℃), 1.7 persons/million (60.0 ℃) and 9.1 × 10^-7 persons/million (70.0 ℃). The results of sensitivity analysis showed that the water temperature (70.0 ℃), initial pollution concentration, room storage time and temperature were important factors of risk. Conclusion: Controlling the contamination level of Cronobacter sakazakii in infant formula powder, controlling the feeding time within 3 h, storing in refrigerator and mixing with water with temperature not lower than 70.0 ℃ are effective measures to prevent infants from eating infant formula powder infected by Cronobacter sakazakii.

Comprehensive metabolism study of Tangeretin in rat plasma, urine and faeces using ultra-high performance liquid chromatography-Q Exactive hybrid quadrupole-orbitrap high-resolution accurate mass spectrometry

BACKGROUND

Tangeretin, present in citrus fruits, is a polymethoxy flavone with extensive pharmacological effects. It has been widely used in the clinic, but there were no detailed studies on the in vivo metabolism of tangeretin.

OBJECTIVE

This study aimed to establish a rapid and effective strategy to identify the metabolites of tangeretin and evaluate the biotransformation pathways of tangeretin in rats.

METHODS

The ultra-high performance liquid chromatography (UHPLC) equipped with a Q-Exactive Orbitrap mass spectrometer was used to identify the metabolites of tangeretin in plasma, urine and faeces of rats after intragastric administration. Based on high-resolution extracted ion chromatograms (HREICs) and parallel reaction monitoring mode (PRM), metabolites of tangeretin were identified by comparing the accurate mass, chromatographic retention times, diagnostic product ions (DPIs) and neutral loss fragments (NLFs) with those of tangeretin reference standard. Isomers were distinguished by ClogP values.

RESULTS

An efficient and integrated strategy was established for the comprehensive screening and characterizing of tangeretin metabolites through Rapid Profiling. Based on this strategy, a total of 52 metabolites were detected and identified, among which 25 metabolites were found in rat plasma, while 48 and 16 metabolites were characterized from rat urine and faeces, respectively. These metabolites were produced by demethylation, demethoxylation, hydroxylation, methoxylation, glucuronidation, glycosylation, sulfation, and their composite reactions. Interestingly, tangeretin is easy to lose methyl in vivo and becomes an intermediate product, and then other phase I and phase II reactions occur. Moreover, the characteristic fragmentation pathways of tangeretin were summarized for the subsequent metabolite identification.

CONCLUSION

The analytical method based on UHPLC-Q-Exactive mass spectrometer has the ability to quickly clarify unknown metabolism. And the the comprehensive metabolism study of tangeretin provided an overall metabolic profile, which will be of great scientific basis for further studies on tangeretin in determining its pharmacokinetics, the bioactivity of the metabolites, and clinical applications.

[Changes of brain network characteristics in patients with depression before and after precise repetitive transcranial magnetic stimulation]

Objective: To investigate the changes of brain network characteristics in patients with depression before and after precise repetitive transcranial magnetic stimulation (rTMS) treatment. Methods: Patients with depression in the Second Affiliated Hospital of Xinxiang Medical University and healthy volunteers in the community of Xinxiang city from February 2018 to March 2019 were simultaneously recruited. The left dorsolateral prefrontal cortex was precisely selected as the stimulation target through the latest Human Brainnetome Atlas, and the near infrared navigation was used to achieve accurate brain stimulation treatment in combination with the structural magnetic resonance data. Moreover, functional connectivity was analyzed before and after rTMS treatment in significantly altered brain areas of patients with depression. Results: Nineteen patients (11 males and 8 females) with depression were included, aged (34±11) years. Meanwhile, 22 healthy controls (9 males and 13 females), aged (30±9) years, were also enrolled. Functional connectivity of insular cortex was decreased in depression patients when the insula was analyzed as the target area (P<0.05). The functional connection from insula to middle frontal lobe and superior parietal lobe in patients with depression decreased before rTMS treatment (P<0.05), but increased after rTMS treatment (P<0.05). The functional connection between dIg_L of the insula and the right middle prefrontal lobe was correlated with Beck Anxiety Index (BAI) before rTMS treatment and Beck Depression Index (BDI) after rTMS treatment (r=0.737, P=0.003; r=0.696, P=0.005). Conclusions: Abnormal functional connectivity of insula may be the brain imaging mechanism of rTMS treatment. Precise brain region selection based on Human Brainnetome Atlas provides a new technical method for clinical rTMS precision treatment.

Physiological effects of γ-aminobutyric acid application on cold tolerance in Medicago ruthenica

Low temperatures in the seedling stage during early spring limit Medicago ruthenica germination and seedling growth. Elucidating the physiological mechanism of γ-aminobutyric acid (GABA)-regulated cold tolerance in M. ruthenica could provide a reference for alleviating the harmful effects of low temperatures on legumes in alpine meadows. The regulatory effects of GABA on M. ruthenica physiological parameters were explored by simulating the ground temperatures in the alpine meadow area of Tianzhu, China, in early May (2 h at 7°C; 6 h at 15°C; 4 h at 12°C; 2 h at 7°C; 10 h at 3°C). Our results showed that 15 mmol/l GABA was the optimal spray concentration to promote growth in the aboveground and belowground parts and increase the fresh and dry weights of seedlings. At this concentration, GABA enhanced the activities of catalase, peroxidase, superoxide dismutase, and ascorbate peroxidase; increased the osmotic balance; and inhibited the production of harmful substances in the cells under low-temperature conditions. GABA also regulated the tissue structure of leaves, increased the cell tense ratio, maintained photochemical activity, increased the amount of light energy to the photochemical reaction center, and improved the photosynthetic rate. Furthermore, exogenous GABA application increased the endogenous GABA content by promoting GABA synthesis in the early stages of low-temperature stress but mainly participated in low-temperature stress mitigation via GABA degradation in the late stages. Our results show that GABA can improve the cold tolerance of M. ruthenica by promoting endogenous GABA metabolism, protecting the membrane system, and improving the leaf structure.