[Mechanism of astragaloside â £ combined with Panax notoginseng saponins in regulating angiogenesis to treat cerebral ischemia based on network pharmacology and experimental verification].

Network pharmacology and animal and cell experiments were employed to explore the mechanism of astragaloside Ⅳ(AST Ⅳ) combined with Panax notoginseng saponins(PNS) in regulating angiogenesis to treat cerebral ischemia. The method of network pharmacology was used to predict the possible mechanisms of AST Ⅳ and PNS in treating cerebral ischemia by mediating angiogenesis. In vivo experiment: SD rats were randomized into sham, model, and AST Ⅳ(10 mg·kg~(-1)) + PNS(25 mg·kg~(-1)) groups, and the model of cerebral ischemia was established with middle cerebral artery occlusion(MCAO) method. AST Ⅳ and PNS were administered by gavage twice a day. the Longa method was employed to measure the neurological deficits. The brain tissue was stained with hematoxylin-eosin(HE) to reveal the pathological damage. Immunohistochemical assay was employed to measure the expression of von Willebrand factor(vWF), and immunofluorescence assay to measure the expression of vascular endothelial growth factor A(VEGFA). Western blot was employed to determine the protein levels of vascular endothelial growth factor receptor 2(VEGFR2), VEGFA, phosphorylated phosphatidylinositol 3-kinase(p-PI3K), and phosphorylated protein kinase B(p-AKT) in the brain tissue. In vitro experiment: the primary generation of rat brain microvascular endothelial cells(rBEMCs) was cultured and identified. The third-generation rBMECs were assigned into control, model, AST Ⅳ(50 µmol·L~(-1)) + PNS(30 µmol·L~(-1)), LY294002(PI3K/AKT signaling pathway inhibitor), 740Y-P(PI3K/AKT signaling pathway agonist), AST Ⅳ + PNS + LY294002, and AST Ⅳ + PNS + 740Y-P groups. Oxygen glucose deprivation/re-oxygenation(OGD/R) was employed to establish the cell model of cerebral ischemia-reperfusion injury. The cell counting kit-8(CCK-8) and scratch assay were employed to examine the survival and migration of rBEMCs, respectively. Matrigel was used to evaluate the tube formation from rBEMCs. The Transwell assay was employed to examine endothelial cell permeability. Western blot was employed to determine the expression of VEGFR2, VEGFA, p-PI3K, and p-AKT in rBEMCs. The results of network pharmacology analysis showed that AST Ⅳ and PNS regulated 21 targets including VEGFA and AKT1 of angiogenesis in cerebral infarction. Most of these 21 targets were involved in the PI3K/AKT signaling pathway. The in vivo experiments showed that compared with the model group, AST Ⅳ + PNS reduced the neurological deficit score(P<0.05) and the cell damage rate in the brain tissue(P<0.05), promoted the expression of vWF and VEGFA(P<0.01) and angiogenesis, and up-regulated the expression of proteins in the PI3K/AKT pathway(P<0.05, P<0.01). The in vitro experiments showed that compared with the model group, the AST Ⅳ + PNS, 740Y-P, AST Ⅳ + PNS + LY294002, and AST Ⅳ + PNS + 740Y-P improved the survival of rBEMCs after OGD/R, enhanced the migration of rBEMCs, increased the tubes formed by rBEMCs, up-regulated the expression of proteins in the PI3K/AKT pathway, and reduced endothelial cell permeability(P<0.05, P<0.01). Compared with the LY294002 group, the AST Ⅳ + PNS + LY294002 group showed increased survival rate, migration rate, and number of tubes, up-regulated expression of proteins in the PI3K/AKT pathway, and decreased endothelial cell permeability(P<0.05,P<0.01). Compared with the AST Ⅳ + PNS and 740Y-P groups, the AST Ⅳ + PNS + 740Y-P group presented increased survival rate, migration rate, and number of tubes and up-regulated expression of proteins in the PI3K/AKT pathway, and reduced endothelial cell permeability(P<0.01). This study indicates that AST Ⅳ and PNS can promote angiogenesis after cerebral ischemia by activating the PI3K/AKT signaling pathway.

Copper Current Collector: The Cornerstones of Practical Lithium Metal and Anode-Free Batteries.

Comparing with the commercial Li-ion batteries, Li metal secondary batteries (LMB) exhibit unparalleled energy density. However, many issues have hindered the practical application. As an element in lithium metal and anode-free batteries, the role of current collector is critical. Comparing with the cathode current collector, more requirements have been imposed on anode current collector as the anode side is usually the starting point of thermal runaway and many other risks, additionally, the anode in Li metal battery very likely determines the cycling life of full cell. In the review, we first give a systematic introduction of copper current collector and the related issues and challenges, and then we summarize the main approaches that have been mentioned in the research, including Cu current collector with 3D architecture, lithophilic modification of the current collector, artificial SEI layer construction on Cu current collector and carbon or polymer decoration of Cu current collector. Finally, we give a prospective comment of the future development in this field.

Improvement of Efficiency in Kesterite Solar Cells by Intentionally Inserting a Thin MoS2 Layer into the Back Interface.

A Mo(S,Se)2 interfacial layer is formed inevitably and uncontrollably between the Mo electrode and Cu2ZnSn(S,Se)4 (CZTSSe) absorber during the selenization process, which significantly influences the performance of CZTSSe solar cells. In this work, an ultrathin MoS2 layer is intentionally inserted into Mo/CZTSSe to reduce the recombination and thus optimize the interface quality. It is revealed that the absorber exhibits a continuous and compact morphology with bigger grains and remarkably without pinholes across the surface or cross-sectional regions after MoS2 modification. Benefitting from this, the shunt resistance (RSh) of the device increased evidently from ∼395 to ∼634 Ω·cm2, and simultaneously, the reverse saturation current density (J0) realized an effective depression. As a result, the power conversion efficiency (PCE) of the MoS2-modified device reaches 9.64% via the optimization of the thickness of the MoS2 layer, indicating performance improvements with respect to the MoS2-free case. Furthermore, the main contribution to the performance improvement is derived and analyzed in detail from the increased RSh, decreased J0, and diode ideality factor. Our results suggest that the Mo/CZTSSe interface quality and performance of CZTSSe solar cells can be modulated and improved by appropriately designing and optimizing the thickness of the inserted MoS2 layer.

The role and controversy of pelvic lymph node dissection in prostate cancer treatment: a focused review.

Pelvic lymph node dissection (PLND) is commonly performed alongside radical prostatectomy. Its primary objective is to determine the lymphatic staging of prostate tumors by removing lymph nodes involved in lymphatic drainage. This aids in guiding subsequent treatment and removing metastatic foci, potentially offering significant therapeutic benefits. Despite varying recommendations from clinical practice guidelines across countries, the actual implementation of PLND is inconsistent, partly due to debates over its therapeutic value. While high-quality evidence supporting the superiority of PLND in oncological outcomes is lacking, its role in increasing surgical time and risk of complications is well-recognized. Despite these concerns, PLND remains the gold standard for lymph node staging in prostate cancer, providing invaluable staging information unattainable by other techniques. This article reviews PLND's scope, guideline perspectives, implementation status, oncologic and non-oncologic outcomes, alternatives, and future research needs.

An optimal genomic DNA extraction method for shoots of four Dendrocalamus species based on membership function analysis.

High-quality genomic DNA extraction is fundamental for the study of gene cloning and expression in plants. Therefore, this study evaluated several methods for extracting genomic DNA from shoots of four Dendrocalamus species to determine the optimal technique. Genomic DNA was extracted using three different methods: a commercial DNA extraction kit method, a modified cetyltrimethylammonium bromide method and a sodium dodecyl sulfate method. A membership function analysis was employed to compare these methods. The results demonstrated that the commercial DNA extraction kit method was the most effective and comprehensive approach for extracting genomic DNA from shoots of four Dendrocalamus species. Furthermore, this study provided valuable insights into optimizing techniques for extracting genomic DNA in other bamboo species.

[Role and mechanisms of CHI3L1 in coronary artery lesions in a mouse model of Kawasaki disease-like vasculitis]. / CHI3L1åœ¨å·å´Žç— æ ·è¡€ç®¡ç‚Žå°é¼ æ¨¡åž‹å† çŠ¶åŠ¨è„‰æŸä¼¤ä¸­çš„ä½œç”¨åŠæœºåˆ¶ç ”ç©¶.

OBJECTIVES: To explore the role and potential mechanisms of chitinase-3-like protein 1 (CHI3L1) in coronary artery lesions in a mouse model of Kawasaki disease (KD)-like vasculitis. METHODS: Four-week-old male SPF-grade C57BL/6 mice were randomly divided into a control group and a model group, with 10 mice in each group. The model group mice were intraperitoneally injected with 0.5 mL of lactobacillus casei cell wall extract (LCWE) to establish a mouse model of KD-like vasculitis, while the control group mice were injected with an equal volume of normal saline. The general conditions of the mice were observed on the 3rd, 7th, and 14th day after injection. Changes in coronary artery tissue pathology were observed using hematoxylin-eosin staining. The level of CHI3L1 in mouse serum was measured by enzyme-linked immunosorbent assay. Immunofluorescence staining was used to detect the expression and localization of CHI3L1, von Willebrand factor (vWF), and α-smooth muscle actin (α-SMA) in coronary artery tissue. Western blot analysis was used to detect the expression of CHI3L1, vWF, vascular endothelial cadherin (VE cadherin), Caspase-3, B cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein (Bax), nuclear factor κB (NF-κB), and phosphorylated NF-κB (p-NF-κB) in coronary artery tissue. RESULTS: The serum level of CHI3L1 in the model group was significantly higher than that in the control group (P<0.05). Compared to the control group, the expression of CHI3L1 in the coronary artery tissue was higher, while the expression of vWF was lower in the model group. The relative expression levels of CHI3L1, Bax, Caspase-3, NF-κB, and p-NF-κB were significantly higher in the model group than in the control group (P<0.05). The relative expression levels of vWF, VE cadherin, and Bcl-2 were lower in the model group than in the control group (P<0.05). CONCLUSIONS: In the LCWE-induced mouse model of KD-like vasculitis, the expression levels of CHI3L1 in serum and coronary arteries increase, and it may play a role in coronary artery lesions through endothelial cell apoptosis mediated by inflammatory reactions.

Effect of preoperative prophylactic antibiotic use on postoperative infection after percutaneous nephrolithotomy in patients with negative urine culture: a single-center randomized controlled trial.

PURPOSE: To compare the effects of different preoperative antibiotic prophylaxis (ABP) regimens on the incidence of sepsis after percutaneous nephrolithotomy (PCNL) in patients with negative urine culture. METHODS: A single-center, randomized controlled trial (June 2022-December 2023) included 120 patients with negative preoperative urine cultures for upper urinary tract stones who underwent PCNL (chictr.org.cn; ChiCTR2200059047). The experimental group and the control group were respectively given different levofloxacin-based preoperative ABP regimes, including 3 days before surgery and no ABP before surgery. Both groups were given a dose of antibiotics before the operation. The primary outcome was differences in the incidence of postoperative sepsis. RESULTS: A total of 120 subjects were included, including 60 patients in the experimental group and 60 patients in the control group. The baseline characteristics of the two groups were comparable and intraoperative characteristics also did not differ. The sepsis rate was not statistically different between the experimental and control groups (13.3% vs.13.3%, P = 1.0). A multivariate logistic regression analysis revealed that body mass index (BMI) (OR = 1.3; 95% CI = 1.1-1.6; P = 0.003) and operating time (OR = 1.1; 95% CI = 1.0-1.1; P = 0.012) were independent risk factors of sepsis. CONCLUSION: Our study showed that prophylactic antibiotic administration for 3 days before surgery did not reduce the incidence of postoperative sepsis in patients with negative urine cultures undergoing PCNL. For this subset of patients, we recommend that a single dose of antibiotics be given prior to the commencement of surgery seems adequate.

The influence of preoperative urodynamic parameters on clinical results in patients with benign prostatic hyperplasia after transurethral resection of the prostate.

PURPOSE: To identify the urodynamic parameters affecting the clinical outcomes of transurethral resection of the prostate(TURP) surgery for patients with benign prostatic hyperplasia(BPH) by multifactor analysis and establish a regression model with diagnostic values. METHODS: The medical records of patients who underwent TURP surgery for BPH between December 2018 and September 2021 were collected from the urology department of the Second Affiliated Hospital of Kunming Medical University, Kunming, China. The patients' clinical data and urodynamic parameters were collected before surgery. The urodynamic parameters affecting surgical efficacy were identified by multifactor analysis, and a regression model with diagnostic values was established and evaluated. RESULTS: A total of 201 patients underwent TURP, of whom 144 had complete preoperative urodynamic data. Each urodynamic factor was subjected to multifactor analysis, and the bladder contractility index (BCI), bladder outflow obstruction index (BOOI), bladder residual urine, and bladder compliance (BC) were found to be independent influence factors on the efficacy of TURP in patients with BPH. The diagnostic value of the regression model was analyzed by receiver operating characteristics (ROC) analysis, and it was found that the AUC = 0.939 (95% CI 0.886-0.972), for which the sensitivity and specificity were 95.19% and 80%, respectively. CONCLUSIONS: The regression model had high diagnostic sensitivity and specificity in predicting the efficacy of surgery, and the diagnostic value was higher than that of individual urodynamic factors. Therefore, BCI, BOOI, bladder residual urine, and BC should be considered as independent influence factors on the efficacy of TURP surgery for BPH.

Conbercept combined with laser photocoagulation in the treatment of diabetic macular edema and its influence on intraocular cytokines.

BACKGROUND: The prevalence of diabetes mellitus (DM) in China is high, and the base is broad. Diabetic retinopathy (DR) is a critical condition affecting the life and health of a nation and its economic development. DR is a common complication of DM. AIM: To investigate the efficacy of laser photocoagulation combined with intravitreal injection of conbercept for treating macular edema. METHODS: Overall, 130 patients with diabetic macular edema (DME) hospitalized in The Third People's Hospital of Changzhou from January 2019 to June 2022 were retrospectively included. According to the treatment plan, 130 patients with DME were categorized into an observation and a control group, with 65 patients in each group. The control group received laser photocoagulation, and the observation group received laser photocoagulation with intravitreal injection of conbercept. Observe changes in vision, cytokines in the eye and so on. RESULTS: The total efficacy rate in the observation group (93.85%) was higher than that in the control group (78.46%) (P < 0.05). In both groups, the best corrected visual acuity correction effect improved after treatment, and the observation group was superior to the control group (P < 0.05). Retinal thickness and central macular thickness improved after treatment, and the observation group was superior to the control group (P < 0.05). The levels of vascular endothelial growth factor, interleukin-6, soluble intercellular adhesion molecule-1, and basic fibroblast growth factor in both groups improved after treatment, and the observation group was superior to the control group (P < 0.05). CONCLUSION: In patients with macular edema, combining laser photocoagulation and intravitreal injections of conbercept for DME is a more effective and safer strategy to improve vision, and lower intraocular cytokine levels.

Plant Proteins: Methods of Quality Assessment and the Human Health Benefits of Pulses.

As countries increase their standard of living and individual income levels rise, there is a concomitant increase in the demand for animal-based protein. However, there are alternative sources. One of the alternatives available is that of increased direct human consumption of plant proteins. The quality of a dietary protein is an important consideration when discussing the merits of one protein source over another. The three most commonly used methods to express protein quality are the protein efficiency ratio (PER), a weight gain measurement; protein digestibility-corrected amino acid score (PDCAAS); and the digestible indispensable amino acid score (DIAAS). The possibility that alterations in the quality and quantity of protein in the diet could generate specific health outcomes is one being actively researched. Plant-based proteins may have additional beneficial properties for human health when compared to animal protein sources, including reductions in risk factors for cardiovascular disease and contributions to increased satiety. In this paper, the methods for the determination of protein quality and the potential beneficial qualities of plant proteins to human health will be described.

Design, Synthesis and Characterization of Palladium-Functionalized Covalent Organic Framework and Its Application as Heterogeneous Catalysis for C-H Arylation of Azoles.

A novel triazine-based covalent organic framework (TFPT-Bz COF) has been constructed by the condensation of 2,4,6-tris(5-formyl-2-pyridinoxy)-1,3,5-triazine (TFPT) and benzidine (BZ) with deep eutectic solvent (DES) as the reaction medium. After the introduction of Pd ions through strong coordination to TFPT-Bz COF matrix, the constructed TFPT-Bz COF/Pd composite exhibited excellent catalytic activity for C-H arylation of azoles with aryl halides in 2-methyltetrahydrofuran. The protocol allows the arylation of a variety of substituted azoles with diverse aryl halides in high to excellent yield. Moreover, the TFPT-Bz COF/Pd catalyst can be recycled several times without significantly reducing its activity.

Noncanonical contribution of microglial transcription factor NR4A1 to post-stroke recovery through TNF mRNA destabilization.

Microglia-mediated neuroinflammation is involved in various neurological diseases, including ischemic stroke, but the endogenous mechanisms preventing unstrained inflammation is still unclear. The anti-inflammatory role of transcription factor nuclear receptor subfamily 4 group A member 1 (NR4A1) in macrophages and microglia has previously been identified. However, the endogenous mechanisms that how NR4A1 restricts unstrained inflammation remain elusive. Here, we observed that NR4A1 is up-regulated in the cytoplasm of activated microglia and localizes to processing bodies (P-bodies). In addition, we found that cytoplasmic NR4A1 functions as an RNA-binding protein (RBP) that directly binds and destabilizes Tnf mRNA in an N6-methyladenosine (m6A)-dependent manner. Remarkably, conditional microglial deletion of Nr4a1 elevates Tnf expression and worsens outcomes in a mouse model of ischemic stroke, in which case NR4A1 expression is significantly induced in the cytoplasm of microglia. Thus, our study illustrates a novel mechanism that NR4A1 posttranscriptionally regulates Tnf expression in microglia and determines stroke outcomes.

The Influence of Preoperative Hydronephrosis on the Prognosis after Radical Cystectomy among Patients with Different Pathological Stages of Bladder Cancer.

INTRODUCTION: Preoperative hydronephrosis is closely associated with the prognosis of patients with bladder cancer. This study assesses the effect of preoperative hydronephrosis on the prognosis after radical cystectomy (RC) among patients with different pathological stages of bladder urothelial carcinoma. METHODS: We retrospectively analyzed the clinical data of 231 patients who underwent RC because of bladder urothelial carcinoma at our institution from January 2013 to December 2017. The overall survival (OS) in patients with or without preoperative hydronephrosis was followed up and compared, and the prognostic role that preoperative hydronephrosis played in patients with different pathological stages of bladder cancer was analyzed. Multivariate analysis was performed with the help of Cox proportional hazards regression models, the postoperative survival was analyzed with the help of Kaplan-Meier plots and log-rank test, and the p values of multiple testing were corrected using the Bonferroni correction. RESULTS: Of 231 patients, 96 were patients with preoperative hydronephrosis and 115 patients had died by the end of the follow-up. Survival analysis found the 3- and 5-year survival rates after radical surgery of patients with preoperative hydronephrosis were significantly lower than those of patients without preoperative hydronephrosis (p < 0.001). Multivariate analysis found preoperative hydronephrosis, T stage of tumor, and lymphatic metastasis were independent influencing factors of postoperative OS (p < 0.05). Survival analysis of subgroups according to pathological stages found in pT3-4N0M0 patients had a significant difference in postoperative survival between the group with preoperative hydronephrosis and the group without preoperative hydronephrosis (p < 0.0001). CONCLUSION: The results indicate that preoperative hydronephrosis mainly affects postoperative OS in the patients whose pathological stage of bladder cancer is pT3-4N0M0.

Early growth response factor 1 upregulates pro-fibrotic genes through activation of TGF-ß1/Smad pathway via transcriptional regulation of PAR1 in high-glucose treated HK-2 cells.

Tubulointerstitial fibrosis (TIF) makes a key role in diabetic kidney disease (DKD). In this study, we revealed that the expressions of Egr1 and protease-activated receptor 1 (PAR1) were increased in renal tissues of DKD rats. In vitro experiments demonstrated that both Egr1 overexpression and high glucose (HG) condition could promote the expressions of PAR1, fibronectin (FN) and collagen I (COL I). Furthermore, HG stimulation enhanced the binding capacity of Egr1 to PAR1 promoter. Both HG condition and Egr1 upregulation could increase, and thrombin inhibitor did not affect activity of TGF-ß1/Smad pathway via PAR1. Collectively, Egr1 is involved in TIF of DKD partly through activating TGF-ß1/Smad pathway via transcriptional regulation of PAR1 in HG treated HK-2 cells.

Relationship Between Intimal Thickness on Ultrasonography and Long-Term Patency of Arteriovenous Fistula Restenosis After Cutting Balloon Versus High Pressure Balloon Angioplasty.

BACKGROUND: To investigate the relationship between intimal thickness on ultrasonography and long-term patency of arteriovenous fistula restenosis after cutting balloon and high pressure balloon angioplasty. METHODS: We retrospectively compared the outcomes between cutting balloon angioplasty and high pressure balloon angioplasty in 149 patients with hemodialysis access restenosis. The relationship of intimal thickness and primary assisted patency of hemodialysis access on ultrasonography was investigated as the primary outcome, using Kaplan-Meier survival analysis and Cox proportional hazards model. The second outcomes included residual diameter, blood flow, and venous pressure of hemodialysis access before and after angiography and balloon diameter and inflation pressure. RESULTS: Primary assisted patency in cutting balloon angioplasty was 90.6%, which was significantly (P = 0.001) more than that of 37.9% in high pressure balloon angioplasty during the 20-month follow-up period. Cox proportional hazards model screened significant factors including procedure type (high pressure or cutting, P = 0.004), inflation pressure (P = 0.013), preoperative intimal thickness (P = 0.009), and difference of intimal thickness (P = 0.029). Finally, procedure type (P = 0.012) and preoperative intimal thickness (P = 0.033) were identified for predicting primary assisted patency by multivariate Cox proportional hazards model. CONCLUSIONS: Compared to high pressure balloon angioplasty for treating patients with hemodialysis access restenosis, cutting balloon angioplasty had a better primary assisted patency. The increase of intimal thickness on ultrasonography after angiography was inversely correlated with primary assisted patency.

A new method for estimating ore grade based on sample length weighting.

Estimation of ore grade is very important for the value evaluation of ore deposits, and it directly affects the development of mineral resources. To improve the accuracy of the inverse distance weighting (IDW) method in ore grade estimation and reduce the smoothing effect of the IDW method in grade estimation, the weight calculation method involved in the IDW method was improved. The length parameter of the ore sample was used to calculate the weight of the IDW method. The length of the ore samples was used as a new factor of the weighting calculation. A new method of IDW integrated with sample length weighting (IDWW) was proposed. The grade estimation of Li, Al, and Fe in porcelain clay ore was used as a case study. A comparative protocol for grade estimation via the IDWW method was designed and implemented. The number of samples involved in the estimation, sample combination, sample grade distribution, and other factors affecting the grade estimation were considered in the experimental scheme. The grade estimation results of the IDWW and the IDW methods were used for comparative analysis of grades of the original and combined samples. The estimated results of the IDWW method were also compared with those of the IDW method. The deviation analysis of the estimated grade mainly included the minimum, maximum, mean, and coefficient of variation of the ore grade. The estimation effect of IDWW method was verified. The minimum deviations of the estimated grade of Li, Al, and Fe were between 9.129% and 59.554%. The maximum deviations were between 4.210 and 22.375%. The mean deviations were between - 1.068 and 7.187%. The deviations in the coefficient of variation were between 3.076 and 36.186%. The deviations in the maximum, minimum, mean, and coefficients of variation of the IDWW were consistent with those of the IDW, demonstrating the accuracy and stability of the IDWW method. The more the samples involved in the estimation, the greater the estimation deviations of IDW and IDWW methods. The estimated deviations of Li, Al, and Fe were affected by the shape of the grade distribution, when the same estimation parameters were used. The grade distribution pattern of the samples significantly influenced the grade estimation results. The IDWW method offers significant theoretical advantages and addresses the adverse effects of uneven sample lengths on the estimates. The IDWW method can effectively reduce the smoothing effect and improves the utilization efficiency of the original samples.

Functions of silicon and phytolith in higher plants.

Silicon (Si) is abundant in the lithosphere, and previous studies have confirmed that silicon plays an important role in plant growth. Higher plants absorb soluble silicon from soil through roots which is deposited in plant tissues mainly in the form of phytoliths. Based on previous studies, the research progress in silicon and phytoliths in the structural protection, enhancement on photosynthesis and transpiration of plants and plant growth and stress resistance was reviewed. Meanwhile, gaps in phytolith research, including phytolith morphology and function, impact of diverse environmental factors coupling with phytoliths, phytolith characteristics at different stages of plant development and phytoliths in regional vegetation are identified. The paper intends to promote the wider application of phytolith research findings and provides reference for further research on phytoliths.

Shoot differentiation from Dendrocalamus brandisii callus and the related physiological roles of sugar and hormones during shoot differentiation.

Only a few calli regeneration systems of bamboos were successfully established, which limited the research on the physiological mechanism of callus differentiation. In this study, we successfully established the callus differentiation systems of Dendrocalamus brandisii (Munro) via seeds. The results showed that the best medium for the callus induction of D. brandisii seeds was basal Murashige and Skoog (1962) (MS) media amended with 5.0 mg l-1 2,4-D and 0.5 mg l-1 kinetin (KT), and the optimal medium for shoot differentiation was the basal MS media supplemented with 4.0 mg l-1 6-benzylaminopurine (6-BA) and 0.5 mg l-1 1-Naphthaleneacetic acid (NAA). Callus tissues had apparent polarity in cell arrangement and developed their own meristematic cell layers. Alpha-amylase (α-amylase), starch phosphorylase (STP) and sucrose synthase (SUSY) played a dominant role in carbohydrate degradation in callus during shoot differentiation. The pentose phosphate pathway (PPP) and TCA pathways were up-regulated in the shoot-differentiated calli. The dynamics of 6-BA and KT contents in calli were consistent with their concentrations applied in medium. Indoleacetic acid (IAA) synthesis and the related signal transduction were down-regulated, whereas the endogenous CTK contents were up-regulated by the exogenous cytokinin (CTK) application in shoot-differentiated calli, and their related synthesis, transport and signal transduction pathways were also up-regulated. The down-regulated signal transduction pathways of IAA and abscisic acid (ABA) revealed that they did not play the key role in the shoot differentiation of bamboos. Gibberellins (GAs) also played a role in shoot differentiation based on the down-regulation of DELLA and the up-regulation of PIF4 genes. The overexpression of DbSNRK2 and DbFIF4 genes further confirmed the negative role of ABA and the positive role of GAs in shoot differentiation.