Research progress on the mechanism of action and clinical application of remote ischemic post-conditioning for acute ischemic stroke.

Remote ischemic post-conditioning (RIPostC) can reduce cerebral ischemia reperfusion injury (IRI) by inducing endogenous protective effects, the distal limb ischemia post-treatment and in situ ischemia post-treatment were classified according to the site of intervention. And in the process of clinical application distal limb ischemia post-treatment is more widely used and more conducive to clinical translation. Therefore, in this paper, we review the mechanism of action and clinical application of RIPostC in cerebral ischemia, hoping to provide reference help for future experimental directions and clinical translation.

DDR2/STAT3 positive feedback loop mediates the immunosuppressive microenvironment by upregulating PD-L1 and recruiting MDSCs in oxaliplatin-resistant HCC.

BACKGROUND & AIMS: Transcriptome sequencing revealed high expression of discoidin domain receptor 2 (DDR2) in oxaliplatin-resistant hepatocellular carcinoma (HCC). This study aimed to explore the role of DDR2 in oxaliplatin resistance and immune evasion in HCC. METHODS: Oxaliplatin-resistant HCC cell lines were established. The interaction between DDR2 and STAT3 was investigated, along with the mechanisms involved in DDR2/STAT3-mediated PD-L1 upregulation and polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) accumulation both in vitro and in vivo. RESULTS: DDR2 was found to induce the phosphorylation of STAT3, leading to its nuclear translocation. Conversely, the activation of STAT3 enhanced DDR2 expression. A positive feedback loop involving DDR2/STAT3 was identified in oxaliplatin-resistant HCC, associated with PD-L1 upregulation and PMN-MDSCs accumulation was identified in oxaliplatin-resistant HCC. Knockdown of DDR2 and STAT3 sensitized oxaliplatin-resistant HCC cells to oxaliplatin and resulted in decreased PMN-MDSCs and increased CD8+ T cells in the tumor microenvironment. ELISA array and MDSC transwell migration assays indicated that oxaliplatin-resistant HCC cells recruited PMN-MDSCs through CCL20. Dual luciferase reporter assays demonstrated that STAT3 can directly enhance the transcription of PD-L1 and CCL20. Furthermore, treatment with a PD-L1 antibody in combination with CCL20 blockade had significant antitumor effects on oxaliplatin-resistant HCC. CONCLUSIONS: Our findings revealed a positive feedback mechanism involving DDR2 and STAT3 that mediates the immunosuppressive microenvironment and promotes oxaliplatin resistance and immune evasion via PD-L1 upregulation and PMN-MDSCs recruitment. Targeting the DDR2/STAT3 pathway may be a promising therapeutic strategy to overcome immune escape and chemoresistance in HCC.

Application of Multi-Rod Constructs for the Revision of Thoracolumbar Fractures.

OBJECTIVE: The revision procedure for failure of internal fixation after thoracolumbar fracture is controversial. Combined anterior and posterior surgery is associated with higher risk more intraoperative bleeding and tissue damage. The success rate of simple anterior surgery needs further confirmation, and posterior surgery lacks stability of internal fixation. This study evaluates the feasibility and surgical effect of multi-rod constructs in the revision of thoracolumbar fractures. METHODS: Eleven patients with thoracolumbar fractures who underwent previous construct failure and were treated with revision and internal fixation with the multi-rod technique from March 2017 to September 2018 were analyzed. The original internal fixation was removed and replaced in the medial insertion of satellite rods and bone graft. The average follow-up time was 15.97 months. The intraoperation blood loss, the time of the operation, activation and discharge and the rate of rod fracture were calculated. The sagittal Cobb angle before revision, after revision and at the last follow-up were compared. The clinical effect was evaluated by visual analogue scale (VAS) and Oswestry Disability Index questionnaire (ODI). RESULTS: The average operation time was 107 min, the intraoperative blood loss was 131.81 mL, the active time was 1.59 days, and the discharge time was 10.89 days. No rod fractured again during the follow-up period. The paired t-test was used to compare the Cobb angle, VAS score, and ODI before and after surgery. There was significant difference in the sagittal Cobb angle between the pre-revision and the posterior sagittal position (p = 0.000), and no significant difference was found between post-revision and last follow-up (p = 0.551). VAS and ODI were greatly improved at the last follow-up. CONCLUSION: The literature on revision of thoracolumbar fractures is insufficient and comprises varying opinions. This paper proposes a new treatment option. The application of the multi-rod constructs in the revision of thoracolumbar fractures is safe, simple, and effective and might provide guidance for future clinical work.

Association between chronic pain and risk of cardiometabolic multimorbidity: a prospective cohort study.

BACKGROUND: Although chronic pain was deleteriously related to single cardiometabolic diseases, the relationship between chronic pain and cardiometabolic multimorbidity remains unclear. The purpose of this study was to investigate the association between chronic pain with the risk of cardiometabolic multimorbidity. METHODS: A prospective cohort study included 452 818 participants who were free of cardiometabolic multimorbidity at baseline. Chronic pain was assessed in diverse anatomical sites including the head, face, neck/shoulder, stomach/abdominal area, back, hip and knee or 'all over the body'. Participants were classified into six groups according to the amount of chronic pain sites: no chronic pain, chronic pain at one, two, three and four or more sites, and those reporting pain 'all over the body'. Cardiometabolic multimorbidity was defined as the occurrence of at least two cardiometabolic diseases, involving type 2 diabetes, ischaemic heart disease and stroke. RESULTS: After a median follow-up of 13.7 years, 4445 participants developed cardiometabolic multimorbidity. Compared with individuals without chronic pain, those experiencing chronic pain in four or more sites were associated with a 1.82-fold (HR: 1.82, 95% CI: 1.61, 2.06) higher risk of cardiometabolic multimorbidity. Pain distributed 'all over the body' was associated with a 59% (HR: 1.59, 95% CI: 1.30, 1.93) increased risk of cardiometabolic multimorbidity Additionally, individuals who had chronic pain in both the head and stomach/abdomen showed the highest risk with cardiometabolic multimorbidity (HR: 1.88, 95% CI: 1.60, 2.20). CONCLUSIONS: Our findings suggested that there was an elevated risk of cardiometabolic multimorbidity associated with an increased amount of chronic pain sites.

Infection and chronic disease activate a systemic brain-muscle signaling axis.

Infections and neurodegenerative diseases induce neuroinflammation, but affected individuals often show nonneural symptoms including muscle pain and muscle fatigue. The molecular pathways by which neuroinflammation causes pathologies outside the central nervous system (CNS) are poorly understood. We developed multiple models to investigate the impact of CNS stressors on motor function and found that Escherichia coli infections and SARS-CoV-2 protein expression caused reactive oxygen species (ROS) to accumulate in the brain. ROS induced expression of the cytokine Unpaired 3 (Upd3) in Drosophila and its ortholog, IL-6, in mice. CNS-derived Upd3/IL-6 activated the JAK-STAT pathway in skeletal muscle, which caused muscle mitochondrial dysfunction and impaired motor function. We observed similar phenotypes after expressing toxic amyloid-ß (Aß42) in the CNS. Infection and chronic disease therefore activate a systemic brain-muscle signaling axis in which CNS-derived cytokines bypass the connectome and directly regulate muscle physiology, highlighting IL-6 as a therapeutic target to treat disease-associated muscle dysfunction.

A telomere-to-telomere gap-free reference genome assembly of avocado provides useful resources for identifying genes related to fatty acid biosynthesis and disease resistance.

Avocado (Persea americana Mill.) is an economically valuable plant because of the high fatty acid content and unique flavor of its fruits. Its fatty acid content, especially the relatively high unsaturated fatty acid content, provides significant health benefits. We herein present a telomere-to-telomere gapless genome assembly (841.6 Mb) of West Indian avocado. The genome contains 40 629 predicted protein-coding genes. Repeat sequences account for 57.9% of the genome. Notably, all telomeres, centromeres, and a nucleolar organizing region are included in this genome. Fragments from these three regions were observed via fluorescence in situ hybridization. We identified 376 potential disease resistance-related nucleotide-binding leucine-rich repeat genes. These genes, which are typically clustered on chromosomes, may be derived from gene duplication events. Five NLR genes (Pa11g0262, Pa02g4855, Pa07g3139, Pa07g0383, and Pa02g3196) were highly expressed in leaves, stems, and fruits, indicating they may be involved in avocado disease responses in multiple tissues. We also identified 128 genes associated with fatty acid biosynthesis and analyzed their expression patterns in leaves, stems, and fruits. Pa02g0113, which encodes one of 11 stearoyl-acyl carrier protein desaturases mediating C18 unsaturated fatty acid synthesis, was more highly expressed in the leaves than in the stems and fruits. These findings provide valuable insights that enhance our understanding of fatty acid biosynthesis in avocado.

Complete genome sequence of a novel Pseudomonas sp. IT1137 isolated from Antarctic intertidal sediment showing potential for alkane degradation at low temperatures.

Pseudomonas species are known for their diverse metabolic abilities and broad ecological distribution. They are fundamental components of bacterial communities and perform essential ecological functions in the environment. A psychrotrophic Pseudomonas sp. IT1137 was isolated from intertidal sediment in the coastal region of the Fildes Peninsula, King George Island, Antarctica. The strain contained a circular chromosome of 5,346,697 bp with a G + C content of 61.66 mol% and one plasmid of 4481 bp with a G + C content of 64.61 mol%. A total of 4848 protein-coding genes, 65 tRNA genes and 15 rRNA genes were obtained. Genome sequence analysis revealed that strain IT1137 not only is a potentially novel species of the genus Pseudomonas but also harbors functional genes related to nitrogen, sulfur and phosphorus cycling. In addition, genes involved in alkane degradation, ectoine synthesis and cyclic lipopeptide (CLP) production were detected in the bacterial genome. The results indicate the potential of the strain Pseudomonas sp. IT1137 for biotechnological applications such as bioremediation and secondary metabolite production and are helpful for understanding bacterial adaptability and ecological function in cold coastal environments.

Novel insights into necrozoospermia from a single-center study: reference ranges, possible etiology, and impact on male fertility.

ABSTARCT: Necrozoospermia is a poorly documented condition with a low incidence, and its definition and clinical significance are unclear. Herein, we provide a reference range for necrozoospermia and discuss its possible etiology and impact on male fertility and assisted reproductive outcomes. We extracted relevant information from 650 Chinese male partners of infertile couples and statistically analyzed sperm vitality. Necrozoospermia was present in 3.4% (22/650) of our study population, and the lower cut-off value for sperm vitality was 75.3%. We compared two methods for assessing sperm vitality (eosin-nigrosin head staining and hypo-osmotic swelling test [HOST]), for which the percentage in the eosin-nigrosin group (mean ± standard deviation [s.d.]: 77.5% ± 10.5%) was significantly higher than that in the HOST group (mean ± s.d.: 58.1% ± 6.7% [5-10 min after incubation] and 55.6% ± 8.2% [25-30 min after incubation]; both P < 0.001). The incidence of necrozoospermia increased with age (odds ratio [OR] = 1.116, 95% confidence interval [CI]: 1.048-1.189, P = 0.001), while the percentage of normal sperm morphology and DNA fragmentation index (DFI) were significantly associated with necrozoospermia, with ORs of 0.691 (95% CI: 0.511-0.935, P = 0.017) and 1.281 (95% CI: 1.180-1.390, P < 0.001), respectively. In the following 6 months, we recruited 166 patients in the nonnecrozoospermia group and 87 patients in the necrozoospermia group to compare intracytoplasmic sperm injection (ICSI) and pregnancy outcomes between the two groups. The necrozoospermia group had a significantly lower normal fertilization rate (74.7% vs 78.2%, P = 0.041; OR = 0.822; 95% CI: 0.682-0.992) than that in the nonnecrozoospermia group. This study presents substantial information on necrozoospermia to establish comprehensive and applicable reference values for sperm vitality for spontaneous conception and artificially assisted reproductive management.

Assessment of monthly runoff simulations based on a physics-informed machine learning framework: The effect of intermediate variables in its construction.

Hydrological forecasting is of great importance for water resources management and planning, especially given the increasing occurrence of extreme events such as floods and droughts. The physics-informed machine learning (PIML) models effectively integrate conceptual hydrologic models with machine learning (ML) models. In this process, the intermediate variables of PIML models serve as bridges between inputs and outputs, while the impact of intermediate variables on the performance of PIML models remains unclear. To fill this knowledge gap, this study aims to encompass the construction of PIML models based on various hydrologic models, conduct comparative analyses of different intermediate variables based on a case study of 205 CAMELS basins, and further explore the relationship between the performance of PIML models and catchment characteristics. The optimal ML model for constructing PIML is first selected among four ML models within the 205 basins. The PIML models are then developed based on five monthly water balance models, namely TM, XM, MEP, SLM, and TVGM. To quantify the potential impact of difference in intermediate variables, two sets of experiments are further designed and performed, namely S1 with actual evapotranspiration as the intermediate variable and S2 with soil moisture as the intermediate variable. Results show that five PIML models generally outperformed the optimal standalone ML models, i.e., the Lasso model. Specifically, regardless of the choice of intermediate variables, the PIML-XM model consistently outperformed the other models within the same basins. Almost all constructed PIML models are affected by the intermediate variables in monthly runoff simulations. Typically, S1 exhibited better performance compared to S2. A greater impact of aridity index, forest fraction, and catchment area on model performance is observed in S2. These findings improve our understanding of constructing PIML models in hydrology by emphasizing their excellent performance in runoff simulations and highlighting the importance of intermediate variables.

How does psychosocial safety climate cross-level influence work engagement and job burnout: the roles of organization-based self-esteem and psychological detachment.

BACKGROUND: Existing researches on nurses' work engagement and job burnout have mostly stayed at the individual level, and limited researches test the cross-level effects of psychosocial safety climate (PSC). The study aimed to explore the cross-level mediating effect of organization-based self-esteem (OBSE) and the moderating effect of psychological detachment between the relationship of PSC and work engagement and job burnout in nurses. METHODS: The cross-sectional study was conducted during November to December 2022 at a tertiary hospital in a northeastern province of China. Data was collected from 1832 nurses through an online questionnaire. Correlation analyses and hierarchical linear modeling were used to test study hypotheses. RESULTS: The results showed that PSC was positively associated with work engagement, and negatively associated with job burnout. OBSE mediated the effect of PSC on work engagement, as well as job burnout. Additionally, psychological detachment played a moderating role between PSC and work engagement, but no moderating effect was found between PSC and job burnout. CONCLUSIONS: PSC at the organizational level increases work engagement and reduces job burnout by stimulating nurses' high levels of OBSE. Psychological detachment, as a situational factor, enhances the positive influence of PSC on work engagement. The implementation of measures to improve the PSC levels of the organization, and the levels of OBSE and psychological detachment among nurses could help to promote their good work performance.

The mechanism of resveratrol stabilization and degradation by synergistic interactions between constituent proteins of whey protein.

Whey protein isolate (WPI) is mainly composed of ß-lactoglobulin (ß-LG), α-lactalbumin (α-LA) and bovine serum albumin (BSA). The aim of this study was to compare and analyze the influence of WPI and its three main constituent proteins, as well as proportionally reconstituted WPI (R-WPI) on resveratrol. It was found that the storage stability of resveratrol was protected by WPI, not affected by R-WPI, but reduced by individual whey proteins at 45°C for 30 days. The rank of accelerated degradation of resveratrol by individual whey proteins was BSA > α-LA > ß-LG. The antioxidant activity, localization of resveratrol and oxidation of carrier proteins were determined by ABTS, H2O2 assay, synchronous fluorescence, carbonyl and circular dichroism. The non-covalent interactions and disulfide bonds between constituent proteins improved the antioxidant activity of the R-WPI-resveratrol complex, the oxidation stability of the carrier and the solvent shielding effect on resveratrol, which synergistically inhibited the degradation of resveratrol in R-WPI system. The results gave insight into elucidating the interaction mechanism of resveratrol with protein carriers.

Dyadic effects of financial toxicity and social support on the fear of cancer recurrence in breast cancer patients and caregivers: an actor-partner interdependence mediation model.

PURPOSE: In this study, the actor-partner interdependence mediation model (APIMeM) was applied to breast cancer patients and their caregivers to assess the factors that affect the fear of cancer recurrence. In particular, the purpose of this study was to evaluate the mediating effect of social support on financial toxicity and the fear of cancer recurrence, providing an effective basis for developing plans to reduce the level of fear of cancer recurrence. METHODS: This study employed a cross-sectional design, and 405 dyads of breast cancer patients and their caregivers were enrolled. Financial toxicity, social support, and fear of cancer recurrence were assessed by computing comprehensive scores for financial toxicity based on patient-reported outcome measures, the Social Support Rating Scale, and the Fear of Cancer Recurrence Inventory Short Form, respectively. The data were analysed using SPSS 24.0 and AMOS 23.0. RESULTS: The results showed that the fear of cancer recurrence of breast cancer patients and their caregivers was significantly related to dyadic financial toxicity and social support. In addition, the financial toxicity of breast cancer patients and their caregivers had significant actor effects and partner effects on the fear of cancer recurrence through dyadic social support. CONCLUSIONS: The financial toxicity of breast cancer patients and their caregivers could produce actor and partner effects on the fear of cancer recurrence through the mediation of social support, which provided empirical support for improving reducing the level of fear of cancer recurrence among patients and caregivers at the dyadic level.

Adolescent Patients'experiences of Mental Disorders Related to School Bullying.

Objective: The purpose of this study was to explore the real inner experience and nursing needs of adolescent patients who suffered from school bullying, and to develop a treatment plan to restore adolescent mental health. Methods: Using the maximum difference sampling method, 15 adolescent patients were interviewed by psychologists and nurses, and the interview results were analyzed by topic induction. Results: Among the 15 participants, 12 (80%) felt helpless, 13 (86.7%) had serious negative emotions, and 10 (66.7%) felt anxious about personal growth. Based on the semi-structured interviews, the psychological states of participants were summarized into three themes: Helplessness, Severe negative emotions, and Anxiety about personal growth. Under the theme of serious negative emotions, it was further divided into three sub-themes: Frustration and Distrust, Rebellion, Insecurity and depression. These themes reflected the significant impact of school bullying on the psychological status of the participants. Conclusion: The internal experience of adolescent patients with mental disorders caused by school bullying mainly includes helplessness, serious negative emotions and anxiety about personal growth. It is recommended to evaluate and diagnose patients' existing and potential health problems individually during clinical treatment and care. On the basis of comprehensive assessment, psychological counseling should be provided and support from family and school should be sought to promote positive mental health and personal growth of adolescents.

Flavonoid localization in soybean seeds: Comparative analysis of wild (Glycine soja) and cultivated (Glycine max) varieties.

Wild soybean (Glycine soja) is known for its high flavonoid contents, yet the distribution of flavonoids in the seeds is not well understood. Herein, we utilized matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) and metabolomics methods to systematically investigate flavonoid differences in the seed coats and embryos of G. soja and G. max. The results of flavonoid profiles and total flavonoid content analyses revealed that flavonoid diversity and abundance in G. soja seed coats were significantly higher than those in G. max whereas the levels were similar in embryos. Specifically, 23 unique flavonoids were identified in the seed coats of G. soja, including procyanidins, epicatechin derivatives, and isoflavones. Using MALDI-MSI, we further delineated the distribution of the important flavonoids in the cotyledons, hypocotyls, and radicles of the two species. These findings imply that G. soja holds considerable breeding potential to enhance the nutritional and stress resistance traits of G. max.

Optimization of immunosuppression strategies for the establishment of chronic hepatitis E virus infection in rabbits.

Chronic hepatitis E mostly occurs in organ transplant recipients and can lead to rapid liver fibrosis and cirrhosis. Previous studies found that the development of chronic hepatitis E virus (HEV) infection is linked to the type of immunosuppressant used. Animal models are crucial for the study of pathogenesis of chronic hepatitis E. We previously established a stable chronic HEV infection rabbit model using cyclosporine A (CsA), a calcineurin inhibitor (CNI)-based immunosuppressant. However, the immunosuppression strategy and timing may be optimized, and how different types of immunosuppressants affect the establishment of chronic HEV infection in this model is still unknown. Here, we showed that chronic HEV infection can be established in 100% of rabbits when CsA treatment was started at HEV challenge or even 4 weeks after. Tacrolimus or prednisolone treatment alone also contributed to chronic HEV infection, resulting in 100% and 77.8% chronicity rates, respectively, while mycophenolate mofetil (MMF) only led to a 28.6% chronicity rate. Chronic HEV infection was accompanied with a persistent activation of innate immune response evidenced by transcriptome analysis. The suppressed adaptive immune response evidenced by low expression of genes related to cytotoxicity (like perforin and FasL) and low anti-HEV seroconversion rates may play important roles in causing chronic HEV infection. By analyzing HEV antigen concentrations with different infection outcomes, we also found that HEV antigen levels could indicate chronic HEV infection development. This study optimized the immunosuppression strategies for establishing chronic HEV infection in rabbits and highlighted the potential association between the development of chronic HEV infection and immunosuppressants.IMPORTANCEOrgan transplant recipients are at high risk of chronic hepatitis E and generally receive a CNI-based immunosuppression regimen containing CNI (tacrolimus or CsA), MMF, and/or corticosteroids. Previously, we established stable chronic HEV infection in a rabbit model by using CsA before HEV challenge. In this study, we further optimized the immunosuppression strategies for establishing chronic HEV infection in rabbits. Chronic HEV infection can also be established when CsA treatment was started at the same time or even 4 weeks after HEV challenge, clearly indicating the risk of progression to chronic infection under these circumstances and the necessity of HEV screening for both the recipient and the donor preoperatively. CsA, tacrolimus, or prednisolone instead of MMF significantly contributed to chronic HEV infection. HEV antigen in acute infection phase indicates the development of chronic infection. Our results have important implications for understanding the potential association between chronic HEV infection and immunosuppressants.

Activation of secondary metabolite gene clusters in Chaetomium olivaceum via the deletion of a histone deacetylase.

Histone acetylation modifications in filamentous fungi play a crucial role in epigenetic gene regulation and are closely linked to the transcription of secondary metabolite (SM) biosynthetic gene clusters (BGCs). Histone deacetylases (HDACs) play a pivotal role in determining the extent of histone acetylation modifications and act as triggers for the expression activity of target BGCs. The genus Chaetomium is widely recognized as a rich source of novel and bioactive SMs. Deletion of a class I HDAC gene of Chaetomium olivaceum SD-80A, g7489, induces a substantial pleiotropic effect on the expression of SM BGCs. The C. olivaceum SD-80A ∆g7489 strain exhibited significant changes in morphology, sporulation ability, and secondary metabolic profile, resulting in the emergence of new compound peaks. Notably, three polyketides (A1-A3) and one asterriquinone (A4) were isolated from this mutant strain. Furthermore, our study explored the BGCs of A1-A4, confirming the function of two polyketide synthases (PKSs). Collectively, our findings highlight the promising potential of molecular epigenetic approaches for the elucidation of novel active compounds and their biosynthetic elements in Chaetomium species. This finding holds great significance for the exploration and utilization of Chaetomium resources. KEY POINTS: • Deletion of a class I histone deacetylase activated secondary metabolite gene clusters. • Three polyketides and one asterriquinone were isolated from HDAC deleted strain. • Two different PKSs were reported in C. olivaceum SD-80A.

From cup to clock: exploring coffee's role in slowing down biological aging.

Background: Previous research has proposed that coffee consumption may have potential health benefits, yet the effect of coffee on one's biological age has not been determined to date. The purpose of this study is to investigate the influence of coffee drinking on biological aging. Methods: Participants were chosen from the National Health and Nutrition Examination Survey (NHANES) and had to meet the selection criteria. Coffee consumption was evaluated through two 24-hour dietary questionnaires. Biological age was measured using both the PhenoAge and KDM-BA algorithms. Multiple linear and logistic regression models were adopted to analyze the association of coffee consumption with biological aging. Results: A total of 13 384 participants with an average daily coffee consumption of 1.73 cups were included. Participants with higher coffee consumption tended to be older, male, non-Hispanic white; had a higher educational level beyond high school; were more likely to be married; had better financial status; and were less likely to smoke or engage in excessive drinking. These individuals with higher coffee consumption exhibited a younger biological age in relation to their chronological age, as indicated by lower mean advancements in PhenoAge and KDM-BA scores. Furthermore, coffee intake was found to be inversely related to PhenoAge and KDM-BA progressions, as well as to the chances of accelerated biological aging, both in unadjusted and adjusted models. These associations remained consistent across all age and gender groups. Additionally, some heterogeneity was also observed among body mass index and physical activity categories. Conclusions: Coffee drinking was inversely related to biological age advancements and the likelihood of accelerated biological aging. Moderate coffee consumption may offer substantial benefits in reducing biological aging.

Testosterone Exacerbates the Formation of Liver Cancer Induced by Environmental N-Nitrosamines Exposure: Potential Mechanisms and Implications for Human Health.

Background: Humans are frequently exposed to N-nitrosamines through various sources, including diet, cigarette smoking, contaminated water, the atmosphere, and endogenous nitrosation. Exposure to these carcinogens may also contribute to the gender-specific incidence of liver cancer, which is significantly higher in males than in females, possibly due to the influence of endogenous hormones such as testosterone. However, the effect of testosterone on N-nitrosamine-induced liver cancer and its underlying mechanism remains unclear. Purpose: To investigate the effect of testosterone on the development of liver cancer induced by N-nitrosamines exposure. Patients and Methods: Histopathological and immunohistochemical staining techniques were employed to analyze the expression levels and nuclear localizations of key signaling molecules, including androgen receptor (AR), ß-catenin, and HMGB1, in both tumor and non-tumor regions of liver samples obtained from human patients and mice. Results: The findings demonstrated a strong correlation between AR and ß-catenin in the nuclear region of tumor areas. AR also showed a significant correlation with HMGB1 in the cytoplasmic region of non-tumor areas in both human and mice samples. The study further analyzed the expression levels and patterns of these three proteins during the progression of liver tumors. Conclusion: This study confirms that AR has the ability to modulate the expression levels and patterns of ß-catenin and HMGB1 in vivo, thereby exacerbating the progression of liver cancer induced by environmental N-nitrosamines exposure. Importantly, the effect of testosterone on the formation of liver cancer induced by environmental N-nitrosamine exposure intensifies this progression. These findings have important implications for drug safety in clinical practice and emphasize the significance of reducing N-nitrosamines exposure through conscious choices regarding diet and lifestyle to ensure environmental safety.

Influences of elevational gradient on flower size and number of Gentiana lawrencei var. farreri.

Plants can adapt to environmental changes by adjusting their functional traits and biomass allocation. The size and number of flowers are functional traits related to plant reproduction. Life history theory predicts that there is a trade-off between flower size and number, and the trade-off can potentially explain the adaptability of plants. Elevation gradients in mountains provide a unique opportunity to test how plants will respond to climate change. In this study, we tried to better explain the adaptability of the alpine plant Gentiana lawrencei var. farreri in response to climate change. We measured the flower size and number, individual size, and reproductive allocation of G. lawrencei var. farreri during the flowering period along an elevation gradient from 3200 to 4000 m, and explored their relationships using linear mixed-effect models and the structural equation model. We found that with elevation increasing, individual size and flower number decreased and flower size increased, while reproductive allocation remained unchanged. Individual size positively affected flower number, but was not related to flower size; reproductive allocation positively affected flower size, but was not related to flower number; there is a clear trade-off between flower size and number. We also found that elevation decreased flower number indirectly via directly reducing individual size. In sum, this study suggests that G. lawrencei var. farreri can adapt to alpine environments by the synergies or trade-offs among individual size, reproductive allocation, flower size, and flower number. This study increases our understanding of the adaptation mechanisms of alpine plants to climate change in alpine environments.