Flowering in aged white tea: Recovering umami taste and amplifying of stale aroma.

Throughout the natural aging process from new to aged white tea, the flavor evolves into a 'stale flavor', despite the initial umami diminishes. The flowering process, inoculation of Eurotium cristatum to white tea, improves the flavor. The impact on sensory qualities and underlying chemical basis of flowering in aged white tea warrant investigation. Sensory analysis, non-targeted metabolomics and volatilomics together deciphered flavor modifications of flowering in aged white tea from different aging years (FAWTs). Findings indicate the flowering process can recover the umami of aged white tea, enhancing the 'stale flavor'. These changes primarily stem from oxidations of catechins and free amino acids, enrichments of flavonols and soluble sugars, and 16 pivotal aroma compounds from degradations of lipids and glycosides. Additionally, 15 volatile and 39 non-volatile compounds were identified as potential biomarkers for FAWTs. These findings offer a viable strategy to improving the quality of aged white tea.

Increasing Endoglin Deletion in Endothelial Cells Exacerbates the Severity of Brain Arteriovenous Malformation in Mouse.

Endoglin (ENG) mutation causes type 1 hereditary hemorrhagic telangiectasia (HHT1). HHT1 patients have arteriovenous malformations (AVMs) in multiple organs, including the brain. In mice, Eng deletion induced by R26RCreER or SM22αCre leads to AVM development in the brain and other organs. We hypothesized that an increase in Eng- negative ECs will enhance AVM severity. To increase EC Eng deletion, we used a codon-improved cre (icre), which is more potent in recombination of the floxed alleles than the wild-type (WT) cre. R26RCreER;Engf/f mice that have a Rosa promoter driving and tamoxifen (TM)-inducible WT cre expression globally, and PdgfbiCreER;Engf/f mice that have a Pdgfb promoter driving and TM-inducible icre expression in ECs were treated with three intra-peritoneal injections of TM (2.5 mg/25 g of body weight) to delete Eng globally or in the ECs. AAV-VEGF was stereotactically injected into the brain to induce brain focal angiogenesis and brain AVM. We found that icre caused more Eng deletion in the brain, indicated by a lower level of Eng proteins (p < 0.001) and fewer Eng-positive ECs (p = 0.01) than mice with WT cre. Mice with icre-mediated Eng deletion have more abnormal vessels (p = 0.02), CD68+ macrophages (p = 0.002), and hemorrhage (p = 0.04) and less vascular pericyte and smooth muscle coverage than mice with WT cre. In addition, arteriovenous shunts were detected in the intestines of icre mice, a phenotype that has not been detected in WT cre mice before. RNA-seq analysis showed that 8 out of the 10 top upregulated pathways identified by gene ontology (GO) analysis are related to inflammation. Therefore, the increase in Eng deletion in ECs exacerbates AVM severity, which is associated with enhanced inflammation. Strategies that can reduce Eng-negative ECs could be used to develop new therapies to reduce AVM severity for HHT1 patients.

Intraoperative Cavity Local Delivery System with NETs-Specific Drug Release for Post-Breast Cancer Surgery Recurrence Correction.

Postoperative breast cancer recurrence is tricky due to the limited therapeutic options. Transforming growth factors-ß (TGF-ß) is vital in promoting postoperative tumor recurrence. However, conventional blocking strategies fail to satisfy both bio-safety and sufficient relapse correction. Neutrophil extracellular traps (NETs) are essential for the spatiotemporal dynamics of TGF-ß at tumor-resection sites, whose unique mechanism for local TGF-ß amplification could remarkably increase the risk of relapse after surgery. Herein, the principle of NETs formation is ingeniously utilized to construct a surgical residual cavity hydrogel that mimics NETs formation. The hydrogel is prepared based on the electrostatic interaction between histidine (His) and sodium alginate (Alg). Then, arginine deiminase 4 (PAD4) protein is released during NETs formation. Simultaneously, the electrical property of His in hydrogel changes automatically, which further lead to promising localized release of anti-TGF-ß. The hydrogel system can realize specific and selective drug release at targeted NETs site over a prolonged period while exhibiting excellent biocompatibility. Superior breast cancer recurrence inhibition is achieved by suppressing TGF-ß and related indicators, impeding epithelial-mesenchymal transition (EMT) progression, and rectifying the locally exacerbated immunosuppressive environment within NETs. The novel NETs local microenvironment drug release functional hydrogel will provide inspiration for postoperative recurrence correction strategies.

Associations between modifiable risk factors and frailty progression among individuals with pre-frailty.

BACKGROUND: In the context of the present global aging phenomenon, the senior population and pace of aging in China have emerged as prominent issues on the worldwide stage. Frailty, a complicated condition that is closely linked to the clinical syndrome of advancing age, poses a considerable health risk to older individuals. Frailty status was assessed by the frailty index (FI) ranging from 0 to 1, pre-frailty was defined as >0.10 to <0.25, and frailty was defined as ≥0.25. To look at the connection between modifiable risk factors and frailty progression among individuals in the pre-frailty population. METHODS: Using pre-frailty patients as characterized by the 32-frailty index, the study focused on middle-aged and elderly persons from China and ultimately recruited 5,411 participants for analysis. The relationship between modifiable factors and changes in pre-frailty status throughout follow-up was investigated. Modifiable factors were body mass index (BMI), abdominal obesity, smoking status, alcohol use, and sleep status. We employed logistic regression to examine the relationships between modifiable risk factors and changes in pre-frailty status, as well as the associations between modifiable factors scores and the corresponding pre-frailty progression. Additionally, we generated the modifiable factors scores and examined how these related to modifications in the pre-frailty stage. RESULTS: In this study, after a mean follow-up of 6 years, (OR = 0.59, 95%CI: 0.48-0.71) for BMI ≥ 25 kg/m2 and (OR = 0.74, 95%CI: 0.63-0.89) for concomitant abdominal obesity were significantly associated with lower reversal to a healthy state; (OR = 1.24, 95%CI:1.07-1.44) and (OR = 1.25, 95%CI: 1.10-1.42) for the group that negatively progressed further to frailty were significantly associated with increased frailty progression profile. Subsequently, investigation of modifiable factor scores and changes of pre-frailty status found that as scores increased further, frailty developed (OR = 1.12, 95%CI:1.05-1.18), with scores of 3 and 4 of (OR = 1.38, 95%CI: 1.08-1.77) and (OR = 1.52, 95%CI:1.09-2.14). Finally, we also performed a series of stratified analyses and found that rural unmarried men aged 45 to 60 years with less than a high school degree were more likely to develop a frailty state once they developed abdominal obesity. CONCLUSION: In pre-frailty individuals, maintaining more favorable controllable variables considerably enhances the chance of return to normal and, conversely, increase the risk of progressing to the frailty.

HOXD10 attenuates renal fibrosis by inhibiting NOX4-induced ferroptosis.

In chronic kidney disease (CKD), renal fibrosis is an unavoidable result of various manifestations. However, its pathogenesis is not yet fully understood. Here, we revealed the novel role of Homeobox D10 (HOXD10) in CKD-related fibrosis. HOXD10 expression was downregulated in CKD-related in vitro and in vivo fibrosis models. UUO model mice were administered adeno-associated virus (AAV) containing HOXD10, and HOXD10 overexpression plasmids were introduced into human proximal tubular epithelial cells induced by TGF-ß1. The levels of iron, reactive oxygen species (ROS), lipid ROS, the oxidized glutathione/total glutathione (GSSG/GSH) ratio, malonaldehyde (MDA), and superoxide dismutase (SOD) were determined using respective assay kits. Treatment with AAV-HOXD10 significantly attenuated fibrosis and renal dysfunction in UUO model mice by inhibiting NOX4 transcription, ferroptosis pathway activation, and oxidative stress. High levels of NOX4 transcription, ferroptosis pathway activation and profibrotic gene expression induced by TGF-ß1/erastin (a ferroptosis agonist) were abrogated by HOXD10 overexpression in HK-2 cells. Moreover, bisulfite sequencing PCR result determined that HOXD10 showed a hypermethylated level in TGF-ß1-treated HK-2 cells. The binding of HOXD10 to the NOX4 promoter was confirmed by chromatin immunoprecipitation (ChIP) analysis and dual-luciferase reporter assays. Targeting HOXD10 may represent an innovative therapeutic strategy for fibrosis treatment in CKD.

Outcomes of a Double-Cup Construct to Treat Paprosky 3A and 3B Acetabular Defects at a Mean of 39 Months.

BACKGROUND: Modular reconstruction systems based on porous tantalum (PT) prosthetic components have been increasingly used for the treatment of complex acetabular bone defects in revision total hip arthroplasty. We report a novel technique that applies a revision cup as a "super-augment" to form a "double-cup" construct for Paprosky type III defects. METHODS: A retrospective review was conducted on revision total hip arthroplasty cases, comparing those treated with double-cup constructs (DC group, n = 48) to those treated with PT shells and augments (PT group, n = 48). All procedures were performed at the same institute between 2017 and 2022. Clinical outcome evaluation utilized the Harris Hip Score, Oxford Hip Score, and the 36-Item Short Form Survey. Preoperative and postoperative radiographic assessments measured hip center of rotation (COR) position and leg length discrepancy. Additionally, postoperative complications and implant survivorship were monitored during the follow-up period. RESULTS: The clinical outcomes improved substantially in both groups, which showed no significant difference in the Harris Hip Score (P = .786), the Oxford Hip Score (P = .570), and the 36-Item Short Form Survey (P = .691). Compared to the PT group, the reconstruction COR was significantly closer to the anatomic COR (vertical distance: 2.630 versus 7.355 mm, P = .0034; horizontal distance: 1.881 versus -6.413 mm, P < .0001) in Paprosky 3B type defects. Additionally, postoperative leg length discrepancy was less in the DC group (-8.252 versus -1.821 mm, P = .0008). Dislocation was the main complication in the DC group, and only 1 patient received re-revision due to repeated dislocation. The cumulative survival rate of the DC group (100%; 95% confidence interval 100) was better than the PT group (83.4%; 95% confidence interval 70.5 to 98.6) when re-revisions for aseptic loosening were the endpoint (P = .046). CONCLUSIONS: The DC is a reliable revision technique for the reconstruction of Paprosky type III bone defects. Although dislocation remains challenging, the biomechanically superior restoration achieved by this technique lowers the risk of aseptic loosening.

[Simultaneous determination of 31 banned veterinary drugs during egg-laying period in poultry eggs by ultra performance liquid chromatography-tandem mass spectrometry].

The consumption of poultry eggs has increased in recent years owing to the abundance of production and improvements in living standards. Thus, the safety requirements of poultry eggs have gradually increased. At present, few reports on analytical methods to determine banned veterinary drugs during egg-laying period in poultry eggs have been published. Therefore, establishing high-throughput and efficient screening methods to monitor banned veterinary drugs during egg-laying period is imperative. In this study, an analytical method based on ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) combined with QuEChERS-based techniques was developed for the simultaneous determination of 31 banned veterinary drugs encompassing nine drug classes (macrolides, antipyretic and analgesic drugs, sulfonamides, antibacterial synergists, anticoccidials, antinematodes, quinolones, tetracyclines, amphenicols) in different types of poultry eggs. The main factors affecting the response, recovery, and sensitivity of the method, such as the extraction solvent, purification adsorbent, LC separation conditions, and MS/MS parameters, were optimized during sample pretreatment and instrumental analysis. The 31 veterinary drug residues in 2.00 g eggs were extracted with 2 mL of 0.1 mol/L ethylene diamine tetraacetic acid disodium solution and 8 mL 3% acetic acid acetonitrile solution, and salted out with 2 g of sodium chloride. After centrifugation, 5 mL of the supernatant was cleaned-up using the QuEChERS method with 100 mg of octadecylsilane-bonded silica gel (C18), 50 mg of N-propylethylenediamine (PSA), and 50 mg of NH2-based sorbents. After nitrogen blowing and redissolution, the 31 target analytes were separated on a Waters CORTECS UPLC C18 analytical chromatographic column (150 mm×2.1 mm, 1.8 µm) at a flow rate, column temperature, and injection volume of 0.4 mL/min, 30 ℃, and 5 µL, respectively. Among these analytes, 26 analytes were acquired in dynamic multiple reaction monitoring (MRM) mode under positive electrospray ionization (ESI+) conditions using (A) 5 mmol/L ammonium acetate (pH 4.5) and (B) acetonitrile as mobile phases. The gradient elution program was as follows: 0-2.0 min, 12%B-30%B; 2.0-7.5 min, 30%B-50%B; 7.5-10.0 min, 50%B; 10.0-10.1 min, 50%B-100%B; 10.1-12.0 min, 100%B; 12.0-12.1 min, 100%B-12%B; The five other target analytes were acquired in MRM mode under negative electrospray ionization (ESI-) conditions using (A) H2O and (B) acetonitrile as mobile phases. The gradient elution program was as follows: 0-2.0 min, 12%B-40%B; 2.0-6.0 min, 40%B-80%B; 6.0-6.1 min, 80%B-100%B; 6.1-8.0 min, 100%B; 8.0-8.1 min, 100%B-12%B. Matrix-matched external standard calibration was used for quantification. The results showed that all the compounds had good linear relationships within their respective ranges, with correlation coefficients of >0.99. The limits of detection (LODs) and quantitation (LOQs) were 0.3-3.0 µg/kg and 1.0-10.0 µg/kg, respectively. The average recoveries of the 31 banned veterinary drugs spiked at three levels (LOQ, maximum residue limit (MRL), and 2MRL) in poultry eggs ranged from 61.2% to 105.7%, and the relative standard deviations (RSDs) ranged from 1.8% to 17.6%. The developed method was used to detect and analyze banned veterinary drugs in 30 commercial poultry egg samples, including 20 eggs, 5 duck eggs, and 5 goose eggs. Enrofloxacin was detected in one egg with a content of 12.3 µg/kg. The proposed method is simple, economical, practical, and capable of the simultaneous determination of multiple classes of banned veterinary drugs in poultry eggs.

Construction of power network security risk assessment model based on LSA-SVM algorithm in the background of smart grid.

Due to theintricate and interdependent nature of the smart grid, it has encountered an increasing number of security threats in recent years. Currently, conventional security measures such as firewalls, intrusion detection, and malicious detection technologies offer specific protection based on their unique perspectives. However, as the types and concealment of attacksincrease, these measures struggle to detect them promptly and respond accordingly. In order to meet the social demand for the accuracy and computation speed of the power network security risk evaluation model, the study develops a fusion power network security risk evaluation algorithm by fusing the flash search algorithm with the support vector machine. This algorithm is then used as the foundation for building an improved power network security risk evaluation model based on the fusion algorithm.The study's improved algorithm's accuracy is 96.2%, which is higher than the accuracy of the other comparative algorithms; its error rate is 3.8%, which is lower than the error rate of the other comparative algorithms; and its loss function curve convergence is quicker than that of the other algorithms.The risk evaluation model's accuracy is 97.8%, which is higher than the accuracy of other comparative models; the error rate is 1.9%, which is lower than the error rate of other comparative models; the computing time of the improved power network security risk evaluation model is 4.4 s, which is lower than the computing time of other comparative models; and its expert score is high. These findings are supported by empirical analysis of the improved power network security risk evaluation model proposed in the study. According to the study's findings, the fusion algorithm and the upgraded power network security risk evaluation model outperform other approaches in terms of accuracy and processing speed. This allows the study's maintenance staff to better meet the needs of the community by assisting them in identifying potential security hazards early on and taking the necessary preventative and remedial action to ensure the power system's continued safe operation.

Golden-flower fungus (Eurotiwm Cristatum) presents fungal flower aroma as well as accelerates the aging of white tea (Shoumei).

Golden-flower fungus (Eurotiwm Cristatum, EC) is widely inoculated in dark tea to endow a typical fungal floral aroma. Recently, Golden Flower White Tea (GFWT), prepared by transplanting EC-mediated fermentation to white tea (Shoumei, SM) to reform the roughness and coarseness, has attracted much attention attributed to coordinated flavor. However, the bio-chemistry reactions between EC and SM, along with origination of composited aroma are still unclear. Thus, the rejected EC, GFWT leaves and stems after EC removal were separated by layer-by-layer stripping following sensory evaluation, volatiles and microstructure analysis to uncover aroma formation mechanism. In GFWT, EC presents fungal flower aroma rather than contribution of extracellular enzymes secreted by fungus in Fu brick tea. Moreover, the short "flowering process" (7 days) endows SM with a stale, jujube, and sweet aroma, which is regarded as the typical characteristic of aged white tea. This inspires EC-mediated fermentation as a promising rapid aging process.

Limitations and modifications in the clinical application of calcium sulfate.

Calcium sulfate and calcium sulfate-based biomaterials have been widely used in non-load-bearing bone defects for hundreds of years due to their superior biocompatibility, biodegradability, and non-toxicity. However, lower compressive strength and rapid degradation rate are the main limitations in clinical applications. Excessive absorption causes a sharp increase in sulfate ion and calcium ion concentrations around the bone defect site, resulting in delayed wound healing and hypercalcemia. In addition, the space between calcium sulfate and the host bone, resulting from excessively rapid absorption, has adverse effects on bone healing or fusion techniques. This issue has been recognized and addressed. The lack of sufficient mechanical strength makes it challenging to use calcium sulfate and calcium sulfate-based biomaterials in load-bearing areas. To overcome these defects, the introduction of various inorganic additives, such as calcium carbonate, calcium phosphate, and calcium silicate, into calcium sulfate is an effective measure. Inorganic materials with different physical and chemical properties can greatly improve the properties of calcium sulfate composites. For example, the hydrolysis products of calcium carbonate are alkaline substances that can buffer the acidic environment caused by the degradation of calcium sulfate; calcium phosphate has poor degradation, which can effectively avoid the excessive absorption of calcium sulfate; and calcium silicate can promote the compressive strength and stimulate new bone formation. The purpose of this review is to review the poor properties of calcium sulfate and its complications in clinical application and to explore the effect of various inorganic additives on the physicochemical properties and biological properties of calcium sulfate.

Application of chiral stationary phases for the separation of vitamin A acetate isomers.

The separation of vitamin A acetate isomers is essential for quality assurance of e.g. nutrition supplements, cosmetics, and pharmaceutical ingredients. High performance liquid chromatography (HPLC) is currently the most suitable analytical method for tackling this challenging separation task. However, the existing methods based on normal phase chromatography (NPC) are poorly reproducible due to the typical disadvantages of NPC, such as long equilibration times and fluctuation in retention factors. A new reversed phase method developed in our labs allows the separation of the isomers applying a chiral stationary phase (CSP). This phase consists of an immobilized polysaccharide which can be used in every chromatographic mode. However, they are not typically used in reversed phase mode. Through the screening of various stationary phases with different polysaccharide based chiral selectors, the choice of the ideal stationary phase could be confirmed, allowing to draw conclusions about the retention mechanism. The CSP Chiralpak IG-3 was found to be the most suitable among the examined. Regarding the separation mechanism, the spatial helical structure of the polysaccharide derivatives was confirmed to be of particular significance. In addition to the stationary phase, the mobile phase was tested for optimization regarding composition, gradient parameters as well as temperature using chromatographic method optimization software for the sake of method robustness.

Microfluidic strategies for biomimetic lung chip establishment and SARS-CoV2 study.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2), characterized by its high fatality rate and contagious nature, has led to significant morbidity and mortality worldwide, significantly impacting both our daily lives and public health. The respiratory pathway serves as the primary route for SARS-CoV2 propagation within the human body, with the lung acting as the initial target organ. Simultaneously, the lung functions as a protective barrier, preventing the entry of viruses into the bloodstream through the alveolar-capillary barrier. Bioengineered microfluidic lung chips, utilizing advanced near-to-native technologies, offer a novel perspective for comprehending the intricate workings of human lungs and facilitating the discovery of anti-coronavirus drugs to combat the challenges posed by coronavirus disease 2019 (COVID-19). This review aims to introduce the key elements and design types of artificial lung chips that closely resemble in vivo-like niches in terms of both structure and function. Furthermore, quantitative and qualitative techniques for evaluating the functionality of the alveolar-capillary barrier are summarized, confirming the successful construction of lung chip systems through engineering approaches. The prospects and persistent challenges associated with establishing next-generation artificial lung models to meet the demands of virology studies are also discussed.

Silicone rubber sealed channel induced self-healing of large bone defects: Where is the limit of self-healing of bone?

Background: Large defects of long tubular bones due to severe trauma, bone tumor resection, or osteomyelitis debridement are challenging in orthopedics. Bone non-union and other complications often lead to serious consequences. At present, autologous bone graft is still the gold standard for the treatment of large bone defects. However, autologous bone graft sources are limited. Silicon rubber (SR) materials are widely used in biomedical fields, due to their safety and biocompatibility, and even shown to induce nerve regeneration. Materials and methods: We extracted rat bone marrow mesenchymal stem cells (BMMSCs) in vitro and verified the biocompatibility of silicone rubber through cell experiments. Then we designed a rabbit radius critical sized bone defect model to verify the effect of silicone rubber sealed channel inducing bone repair in vivo. Results: SR sealed channel could prevent the fibrous tissue from entering the fracture end and forming bone nonunion, thereby inducing self-healing of long tubular bone through endochondral osteogenesis. The hematoma tissue formed in the early stage was rich in osteogenesis and angiogenesis related proteins, and gradually turned into vascularization and endochondral osteogenesis, and finally realized bone regeneration. Conclusions: In summary, our study proved that SR sealed channel could prevent the fibrous tissue from entering the fracture end and induce self-healing of long tubular bone through endochondral osteogenesis. In this process, the sealed environment provided by the SR channel was key, and this might indicate that the limit of self-healing of bone exceeded the previously thought. The translational potential of this article: This study investigated a new concept to induce the self-healing of large bone defects. It could avoid trauma caused by autologous bone extraction and possible rejection reactions caused by bone graft materials. Further research based on this study, including the innovation of induction materials, might invent a new type of bone inducing production, which could bring convenience to patients. We believed that this study had significant meaning for the treatment of large bone defects in clinical practice.

Neuron Navigator 1 (Nav1) regulates the response to cocaine in mice.

Genetic variation accounts for much of the risk for developing a substance use disorder, but the underlying genetic factors and their genetic effector mechanisms are mostly unknown. Inbred mouse strains exhibit substantial and heritable differences in the extent of voluntary cocaine self-administration. Computational genetic analysis of cocaine self-administration data obtained from twenty-one inbred strains identified Nav1, a member of the neuron navigator family that regulates dendrite formation and axonal guidance, as a candidate gene. To test this genetic hypothesis, we generated and characterized Nav1 knockout mice. Consistent with the genetic prediction, Nav1 knockout mice exhibited increased voluntary cocaine intake and had increased motivation for cocaine consumption. Immunohistochemistry, electrophysiology, and transcriptomic studies were performed as a starting point for investigating the mechanism for the Nav1 knockout effect. Nav1 knockout mice had a reduced inhibitory synapse density in their cortex, increased excitatory synaptic transmission in their cortex and hippocampus, and increased excitatory neurons in a deep cortical layer. Collectively, our results indicate that Nav1 regulates the response to cocaine, and we identified Nav1 knockout induced changes in the excitatory and inhibitory synaptic balance in the cortex and hippocampus that could contribute to this effect.

Theoretical studies of magneto-optical Kerr and Faraday effects in two-dimensional second-order topological insulators.

Optical approaches are useful for studying the electronic and spin structure of materials. Here, based on the tight-binding model and linear response theory, we investigate the magneto-optical Kerr and Faraday effects in two-dimensional second-order topological insulators (SOTI) with external magnetization. We find that orbital-dependent Zeeman term induces band crossings for SOTI phase, which are absent for trivial phase. In the weak-magnetization regime, these crossings give rise to giant jumps (peaks) of Kerr and Faraday angles (ellipticity) for SOTI phase. In the strong-magnetization regime, we find that two nearly flat bands are formed at the high-symmetry point of Brillouin zone of SOTI phase. These flat bands give rise to two successive giant jumps (peaks) of Kerr and Faraday angles (ellipticity). These phenomena provide new possibilities to characterize and detect the two-dimensional SOTI phase.

Anthocyanin metabolism and its differential regulation in purple tea (Camellia sinensis).

Tea plants (Camellia sinensis) typically contain high-flavonoid phytochemicals like catechins. Recently, new tea cultivars with unique purple-colored leaves have gained attention. These purple tea cultivars are enriched with anthocyanin, which provides an interesting perspective for studying the metabolic flux of the flavonoid pathway. An increasing number of studies are focusing on the leaf color formation of purple tea and this review aims to summarize the latest progress made on the composition and accumulation of anthocyanins in tea plants. In addition, the regulation mechanism in its synthesis will be discussed and a hypothetical regulation model for leaf color transformation during growth will be proposed. Some novel insights are presented to facilitate future in-depth studies of purple tea to provide a theoretical basis for targeted breeding programs in leaf color.

Lumbar Extensor and Flexor Muscle Structural Changes in Young Female Nurses with Chronic Bilateral Non-Specific Low Back Pain: A Case-Control Study.

BACKGROUND: Muscle structural studies on non-specific low back pain in young female nurses are rare. This study aimed to investigate the changes of lumbar extensor and flexor muscle cross-sectional area and fatty infiltration in young female nurses with chronic bilateral non-specific low back pain by lumbar spine magnetic resonance imaging to speculate on the possible pathogenesis. METHODS: The magnetic resonance imaging (MRI) data of 58 female nurses with chronic bilateral non-specific low back pain and 60 healthy female controls were analyzed retrospectively. The lumbar extensor and flexor muscle cross-sectional area/intervertebral disc cross-sectional area ratio, as well as magnetic resonance imaging signal intensity of lumbar extensor (erector spinae; multifidus) and flexor muscles (psoas muscle) were measured, calculated and compared between nurses and healthy controls by independent samples t-test. In addition, each mean MRI signal intensity of lumbar extensor or flexor muscles in nurses at different anatomical segments from lumbar vertebrae 2 (L2)-L3 to L5-sacral vertebrae 1 (S1) was also compared, and one-way Analysis of Variance (ANOVA) analyzed the mean MRI signal intensity between muscles in nurses with multiple comparisons. RESULTS: There was no significant difference in lumbar extensor and flexor muscle cross-sectional area/intervertebral disc cross-sectional area ratio between nurses with chronic bilateral non-specific low back pain and healthy controls, p > 0.01. The magnetic resonance imaging signal intensity in lumbar extensor and flexor muscle was significantly higher in nurses with chronic bilateral non-specific low back pain than in healthy controls, p < 0.01. The MRI signal intensity of lumbar extensor muscle at the lower lumbar segments was higher than at the upper ones. The magnetic resonance imaging signal intensity of the extensor muscle (erector spinae; multifidus) was significantly higher than that of the flexor muscle (psoas muscle), p < 0.01. CONCLUSIONS: This study showed that young nurses with chronic bilateral non-specific low back pain have lumbar extensor and flexor muscle fatty infiltration without muscle atrophy. We hypothesized that muscle fatty infiltration may occur prior to muscle atrophy. Therefore, the high fatty infiltration of the lumbar extensor and flexor muscle may be a cause or a result of chronic bilateral non-specific low back pain in young nurses.