石墨烯负载Ti-Ni双金属对MgH_(2)可逆储氢性能的催化改性及机理

MgH_(2)具有7.6 wt%的质量储氢密度,丰富的储量以及低廉的价格,是极具应用前景的储氢材料之一。然而,稳定的热力学性质和缓慢的吸放氢反应动力学导致其吸放氢温度偏高,限制了其实际应用。论文研究了非晶TiH_(2)和纳米Ni负载于石墨烯的Ti-Ni@GR催化剂对MgH_(2)的吸放氢性能的改性及其作用机理。结果表明,MgH_(2)-9 wt%Ti-Ni@GR样品在185℃下即开始放氢,较原始MgH_(2)降低约115℃,且放氢产物在室温下就可以进行氢化反应。引入Ti-Ni@GR也显著改善了MgH_(2)的吸放氢动力学性能,在275℃下,15 min内放氢量达6.2 wt%。在100℃下,5 min就能快速吸氢4.8 wt%。经过10次循环后,样品的储氢容量保持率高达97%。机理研究发现,Ti和Ni的活性催化作用及其均匀分散是体系吸放氢性能改善的主要原因。

Diversity of root-associated fungi of Rhododendron simsii in subtropical forests: fungal communities with high resistance to anthropogenic disturbances

Species of the Ericaceae or heath family are widely distribute in continental ecosystems and their special ericoid mycorrhizas(ERM)are considered benefi cial to their survival and persistence in variable habitats.Currently,increasing anthropogenic disturbances and improper forest management are aff ecting subtropical forests of China where these native species located.These activities not only aff ect plant communities above-ground,but also impose pressures on microbial communities below-ground.In this study,rootassociated fungal communities of Rhododendron simsii in four forest types under diff erent anthropogenic disturbances were identifi ed using an Illumina Miseq platform,i.e.,old growth forests,secondary forests with one cutting(SECⅠ),secondary forests with two cuttings(SECⅡ),and Chinesefi r plantations(PLF).Intra-and inter-annual variations were analyzed by comparing samples taken in diff erent seasons and years.The results show that:(1)over 1000 OTUs were found in hair roots with most from the division Ascomycota and Basidiomycota belonging to diff erent functional groups;(2)while there were a few indicator OTUs specifi c to diff erent forest types,seasons and years,the proportion of shared taxa was quite large,accounting for 44.9–79.4%of the total OTUs;(3)signifi cantly positive correlations were found between disturbance sensitivity and temporal variations in common fungal orders,and both in major fungal orders were signifi cantly diff erent among fungal functional groups in which putative and possible ERM fungi were highly resistant to disturbances and low temporal variations.The high disturbance resistance and temporal persistence of putative ERM fungi may be essential for the successful adaptation of R.simsii in disturbed subtropical forests of China.

Significant association between IL-18 and OCT4 gene polymorphisms in susceptibility and clinical characteristics of prostate cancer

Objective Recent studies have shown abnormal expression of octamer-binding transcription factor 4(OCT4) and interleukin-18(IL-18) to be related to cancer. However, the molecular mechanisms by which the IL-18 and OCT4 gene polymorphisms are associated with prostate cancer remain unclear. In this study, we aimed to determine whether the presence of IL-18 and OCT4 polymorphisms were associated with size, grade, tumor, nodes and metastasis(TNM) stage, or survival in patients with prostate cancer.Methods Polymorphisms in OCT4 and IL-18 genes were evaluated to determine susceptibility to prostate cancer in 120 patients. A control group consisted of 125 Chinese participants. Genotyping was performed using TaqMan allelic discrimination assays, and statistical analysis was performed using SPSS. Results No association was found between OCT4 and IL-18 gene polymorphisms and prostate cancer susceptibility. For OCT4 AA and IL-18-607 CC genotypes, there was a significant association with higher tumor grade(P = 0.03 and P = 0.025) and stage(P = 0.04 and P = 0.001). The OCT4 and IL-18-137 GG genotype was correlated with higher tumor grade(P = 0.028) and stage(P = 0.008). Furthermore, OCT4 AA was significantly more frequent in patients with lymph node metastasis(P = 0.02) and distant metastasis(P = 0.01). The Cox proportional hazard model showed that tumor grade and stage grouping were independent prognostic factors but IL-18 and OCT4 polymorphisms were not. Conclusion The OCT4 gene may have a profound effect on prostate cancer risk. Polymorphism variants in the IL-18(IL-18-607 and IL-18-137) and OCT4 genes may be associated with poor prognoses for individuals with prostate cancer.

Clinical study of IL-18 and NANOG gene polymorphisms in prostate cancer patients

Objective Recent studies have shown abnormal expression of NANOG and IL-18 to be related to cancer. However, the molecular mechanism by which IL-18 and NANOG gene polymorphisms are associated with prostate cancer is unclear. In this study, we examined whether IL-18 and NANOG gene polymorphisms and their interaction with prostate cancer-related risk factor are associated with the susceptibility to and clinicopathological development of prostate cancer among Chinese men.Methods Polymorphisms in the NANOG and IL-18 genes were evaluated for susceptibility in 120 patients with prostate cancer. The control group consisted of 125 samples from Chinese men. Genotyping was conducted using Taq Man allelic discrimination assays. Statistical analysis was performed using SPSS software. Results No association of NANOG and IL-18 gene polymorphisms and overall prostate cancer susceptibility was detected. The IL-18-607 CC genotype was significantly associated with a higher tumor grade(P = 0.025) and stage(P =0.001). The IL-18-137 GG genotype correlated with a higher tumor grade(P = 0.028) and stage(P = 0.008). The IL-18-137 G allele was significantly more frequent in patients with lymph node metastasis(P = 0.035). The IL-18-607 CC genotype was associated with distant metastasis(P = 0.025). However, no significant association was observed between NANOG polymorphisms and any clinicopathological feature. The Cox proportional hazard model showed that tumor grade and stage grouping were independent prognostic factors in IL-18, while IL-18 polymorphism was not. Polymorphism variants in the IL-18(IL-18-607 and IL-18-137) and NANOG(genotypes AC) genes might be associated with a worse prognosis of patients with prostate cancer.Conclusion NANOG may be associated with the early stages of prostate cancer carcinogenesis. IL-18 and NANOG gene polymorphisms may play a major role in the growth, invasion, and metastasis of prostate cancer.

Analysis of the clinical characteristics between cavitating squamous cell lung carcinoma and non-cavitating squamous cell lung carcinoma

Objective: To identify the differences between cavitating squamous cell lung carcinoma (cSLC) and non-cavitating squamous cell lung carcinoma (ncSLC). Methods: Fifty-one patients with cSLC and 281 with ncSLC confirmed by surgery in our hospital between 1999 to 2000 were collected and their clinical, histological and survival features were retrospectively analyzed. Results: Patients with cSLC had more frequent manifestation of infection and weight loss. They usually experienced longer duration of pre-diagnosis and showed bigger tumor mass, larger primary tumor invasion with worse differentiated than ncSLC patients. There was no significant difference in age, sex, smoking history, family tumor history, personal tuberculosis history, disease location, TNM stage, lymph node invasion, and metastasis between the two groups. Median survival time was 29 months for cSLC and 35 months for ncSLC. One- and 3- year survival rates were 86.3% and 43.1% for cSLC vs. 91.1% and 47.0% for ncSLC respectively (P>0.05). Conclusion: Patients with cSLC presented with a bigger mass, a larger extent of primary tumor invasion, worse differentiated, more obstructed pneumonia that might result in longer duration of pre-diagnosis and more weight loss. As lack of differences in disease stages, lymph node invasion, metastasis and especially survival time with ncSLC, cSLC couldn’t be classified as a special type of squamous cell carcinoma by present evidences.

The Influence of PbI₂on Characteristic of Organic-Inorganic Hybrid Perovskite Thin Films

Organic-inorganic hybrid perovskite materials have attracted significant research efforts because of their outstanding properties. Meanwhile the crystallization of organic-inorganic hybrid perovskite materials can significantly influence the films quality. Here, we research the influence of the characteristics of PbI2 thin film on final perovskite films and the mechanisms of film formation based on the two-step sequential deposition method. We found that the characteristics of PbI2 thin film, such as the grain size, the grain shape, the surface roughness and the film densification, have significant effects on the final perovskite films due to different film crystallization process. According to the analysis on the characteristics of the perovskite films obtained from different PbI2precursor, we suggested that the formation of perovskite film begins from the PbI2 crystals expanding when they are converted to MAPbI3 perovskite by migration of MA+ cations from the grain boundaries.

微生物合成生物学在疾病诊疗上的应用进展

在人体的身体内部居住着数以万亿计的细菌和其他微生物,寄生在我们的皮肤、胃肠道和口腔等部位,微生物群失调已成为炎症性肠病、过敏、肥胖、心血管以及神经退行性疾病和癌症等多种疾病发生发展的重要原因。与此同时,利用微生物制剂改善健康状况、治疗疾病也在研究和临床中得到验证。近年来,活体生物药不断被开发用于预防、诊断与治疗疾病。采用合成生物学手段在微生物中设计、构建精准可控的基因电路,获得非致病性、具有疾病微环境感知和响应能力并按需释放治疗药物的活体工程菌,实施活体微生物疗法,已成为临床疾病治疗的新思路和新方法。本文对微生物合成生物学在疾病诊疗中的应用进展,如预防与诊疗病原菌感染、治疗代谢疾病、靶向杀伤肿瘤、缓解炎症等进行了系统性总结,并针对微生物传感器设计和推广到临床应用中面临的问题和未来的发展进行了分析与展望。利用合成生物学在微生物中设计的生物传感器能智能感知疾病微环境并可控地提供药物,在疾病的监测和治疗中有巨大的应用前景。

固溶体MAX相(Ti_(0.5)V_(0.5))_3AlC_2的制备及其对MgH_2储氢性能的催化影响

通过无压烧结法制备了固溶体MAX相(Ti_(0.5)V_(0.5))_3AlC_2,研究了其添加对MgH_2储氢性能的影响。结果发现,固溶体MAX相(Ti_(0.5)V_(0.5))_3AlC_2中的Ti和V元素通过协同作用,呈现出更高的催化活性。添加质量分数10%(Ti_(0.5)V_(0.5))_3AlC_2的MgH_2样品的起始放氢温度为230℃,较原始MgH_2降低了60℃。在275℃下等温放氢,(Ti_(0.5)V_(0.5))_3AlC_2添加样品的放氢速率可达0.35%·min^(-1),是原始MgH_2样品的4倍左右。此外,完全放氢后的MgH_2-10%(Ti_(0.5)V_(0.5))_3AlC_2样品在150℃、5 MPa氢压下,可在60 s内吸收4.7%的氢。计算显示,MgH_2-10%(Ti_(0.5)V_(0.5))_3AlC_2样品的表观活化能为79.6 kJ·mol^(-1),较原始MgH_2(153.8 kJ·mol^(-1))降低了48%,这是MgH_2放氢性能得到改善的主要原因。

超声波对镉胁迫鸭茅和冰草种子萌发的影响

为探讨超声波和重金属镉二因素对鸭茅(Dactylis glomerata L.)和冰草(Agropyron cristatum L.)种子发芽率、胚芽生长和生理活性的影响,设置五种不同时长的超声波处理两种种子,处理后的种子分别用不同浓度的氯化镉溶液进行处理,通过培养皿纸上发芽法培养20d。结果表明:单一超声波处理,均提高鸭茅种子的发芽率且在5min时发芽率最高,冰草种子仅在超声波5min的处理下发芽率提高;超声波时长为5min时显著提高鸭茅幼苗中POD的活性;各超声波处理均使鸭茅幼苗中MDA含量增加。单一镉溶液处理均抑制鸭茅和冰草种子的发芽和胚芽的生长(除浓度为0.04%的镉溶液提高冰草种子的发芽率);0.02%镉显著提高鸭茅幼苗POD的活性,镉溶液对鸭茅幼苗中MDA的含量无显著作用。超声波与镉溶液组合处理下,在0.05%的镉胁迫下,超声波处理10min显著提高鸭茅和冰草种子的发芽率;当镉溶液浓度为0.01%时,各超声波显著促进鸭茅胚芽生长。综合来看,超声波处理可以有效减缓鸭茅和冰草种子的镉胁迫效应,提高种子和成苗活力。

Sanguinarine Attenuates Lipopolysaccharide-induced Inflammation and Apoptosis by Inhibiting the TLR4/NF-KB Pathway in H9c2 Cardiomyocytes

The inflammatory response is involved in the pathogenesis of the most common types of heart disease. Sanguinarine （SAN） has various pharmacological properties such as anti-inflammatory, antioxidant, antibacterial, antitumor, and immune-enhancing properties. However, few studies have investigated the effects of SAN on lipopolysaceharide （LPS）-induced inflammatory and apoptotic responses in H9c2 cardiomyocytes. Therefore, in this study, H9c2 cells were co-treated with SAN and LPS, and the mRNA levels of pro-inflammation markers and the apoptosis rate were measured to clarify the effect of SAN on cardiac inflammation. The underlying mechanism was further investigated by detecting the activation of Toll-like receptor （TLR）4/nuclear faetor-κB （NF-κB） signaling pathways. As a result, increased mRNA expression of interleukin （IL）-1β, IL-6, and TNFα induced by LPS was attenuated after SAN treatment; LPS-induced apoptosis ofHge2 cardiomyocytes and cleaved-caspase 8, 9, 3 were all significantly reduced by SAN. Further experiments showed that the beneficial effect of SAN on blocking the inflammation and apoptosis of H9c2 cardiomyocytes induced by LPS was associated with suppression of the TLR4/NF-κB signaling pathway. It was suggested that SAN suppressed the LPS-induced inflammation and apoptosis of H9c2 cardiomyocytes, which may be mediated by inhibition of the TLR4/NF-κB signaling pathway. Thus, SAN may be a feasible therapy to treat sepsis patients with cardiac dysfunction.

Human natural killer cells for targeting delivery of gold nanostars and bimodal imaging directed photothermal/photodynamic therapy and immunotherapy

Objective:To construct a novel nanoplatform GNS@CaCO3/Ce6-NK by loading the CaCO3-coated gold nanostars(GNSs)with Chlorin e6 molecules(Ce6)into human peripheral blood mononuclear cells(PBMCs)-derived NK cells for tumor targeted therapy.Methods:GNS@CaCO3/Ce6 nanoparticles were prepared and characterized by TEM and UV-vis.The cell surface markers and cytokines secretion of NK cells before and after loading the GNS@CaCO3/Ce6 nanoparticles were detected by Flow Cytometry(FCM)and ELISA.Effects of the GNS@CaCO3/Ce6-NK cells on A549 cancer cells was determined by FCM and CCK-8.Intracellular fluorescent signals of GNS@CaCO3/Ce6-NK cells were detected via Confocal laser scanning microscopic(CLSM)and FCM at different time points.Intracellular ROS generation of GNS@CaCO3/Ce6-NK cells under laser irradiation were examined by FCM.The distribution of GNS@CaCO3/Ce6-NK in A549 tumor-bearing mice were observed by fluorescence imaging and PA imaging.The combination therapy of GNS@CaCO3/Ce6-NK under laser irradiation were investigated on tumor-bearing mice.Results:The coated CaC03 shell on the surface of GNSs exhibited prominent delivery and protection effect of Ce6 during the cellular uptake process.The as-prepared multifunctional GNS@CaCO3/Ce6-NK cells possessed bimodal functions of fluorescence imaging and photoacoustic imaging.The as-prepared multifunctional GNS@CaCO3/Ce6-NK cells could actively target tumor tissues with the enhanced photothermal/photodynamic therapy and immunotherapy.Conclusions:The GNS@CaCO3/Ce6-NK shows effective tumor-targeting ability and prominent therapeutic efficacy toward lung cancer A549 tumor-bearing mice.Through fully utilizing the features of GNSs and NK cells,this new nanoplatform provides a new synergistic strategy for enhanced photothermal/photodynamic therapy and immunotherapy in the field of anticancer development in the near future.

Low carbon storage of woody debris in a karst forest in southwestern China

The properties of woody debris(WD) vary across different forests under various soil conditions.Owing to the relatively shallow and low amounts of soils on karst terrains, it is necessary to determine the WD carbon inventory of karst forests. In this study, we recorded WD with a basal diameter for standing snags and the largeend diameter for fallen logs of ≥ 1 cm. The carbon density of WD in a secondary karst mixed evergreen and deciduous broad-leaved forest that had been clear-cut 55 years ago in southwestern China were inventoried in a 2 ha plot. Woody debris carbon density calculated using specific gravity and carbon concentration was 4.07 Mg C ha^-1. Woody debris with diameters ≥ 10 cm(coarse WD) constituted 53.8% of total carbon storage whereas WD < 10 cm in diameters(fine WD) accounted for more pieces of WD(89.9%).Lithocarpus confinis contributed the most WD carbon(26.5%). Intermediate decayed WD was relatively more abundant, but WD with final decay contributed the least to the total pieces of WD(6.7%). The contribution of WD to carbon storage of karst forest was low compared to other forests worldwide. Significant positive correlations were found between WD carbon and biodiversity(R^2= 0.035,p < 0.01) and elevation(R^2= 0.047, p < 0.01) and negative correlations was found in outcrop coverage(R^2= 0.034, p <0.01). Further studies are needed to elucidate the ecological functions of WD to better understand their roles in maintaining biodiversity, enhancing productivity, and controlling vegetation degradation in karst forest ecosystems.

Human iPS Cells Loaded with MnO2-Based Nanoprobes for Photodynamic and Simultaneous Enhanced Immunotherapy Against Cancer

How to trigger strong anti-tumor immune responses has become a focus for tumor therapy.Here,we report the human-induced pluripotent stem cells(iPSs)to deliver MnO2@Ce6 nanoprobes into tumors for simultaneous photodynamic therapy(PDT)and enhanced immunotherapy.Ce6 photosensitizer was attached on manganese dioxide(MnO2)nanoparticles,and resultant MnO2@Ce6 nanoprobes were delivered into mitomycin-treated iPSs to form iPS-MnO2@Ce6 nanoprobes.The iPS-MnO2@Ce6 actively targeted in vivo tumors,the acidic microenvironment triggered interaction between MnO2 and H2O2,released large quantities of oxygen,alleviated hypoxia in tumor.Upon PDT,singlet oxygen formed,broken iPSs released tumor-shared antigens,which evoked an intensive innate and adaptive immune response against the tumor,improving dendritic cells matured,effector T cells,and natural killer cells were activated.Meanwhile,regulatory T cells were reduced,and then the immune response induced by iPS-MnO2@Ce6 was markedly stronger than the immune reaction induced by MnO2@Ce6(P<0.05).The iPS-MnO2@Ce6 markedly inhibited tumor growth and metastasis and reduced mortality in mice models with tumor.Human iPS s loaded with MnO2-based nanoprobes are a promising strategy for simultaneous PDT and enhanced immunotherapy against tumor and own clinical translational prospect.

Low net primary productivity of dominant tree species in a karst forest, southwestern China： first evidences from tree ring width and girth increment

Aboveground net primary productivity(ANPP)of two dominant species, one deciduous tree(Platycarya strobilacea) and one evergreen tree(Machilus cavaleriei),was estimated based on the tree-ring width and the girth increment as well as allometric functions in a karst evergreen and deciduous broadleaved mixed forest in central Guizhou Province, southwestern China. Results showed that the ANPP increased from 1961 to 2015, especially during the last 20–30 years, but with strong variations. The deciduous tree had higher ANPP than the evergreen tree according to two kinds of estimates by the tree ring and girth increment. The averaged ANPP for these two mature trees was 2.27 kg/individual/year, ca. 8 t/ha/year considering the normal stand density. Such karst forest productivity was lower than the natural subtropical forests in China and in the world.

Bcl6 Suppresses Cardiac Fibroblast Activation and Function via Directly Binding to Smad4

Bcl6,a critical pro-oncogene of human B-cell lymphomas,can promote tumor progress.Previous studies have found that Bcl6 participates in hypoxia injury in cardiomyocytes.However,the effect of Bcl6 on cardiac fibroblasts is still unclear.The aim of this study was to elucidate the functional role of Bcl6 in cardiac fibroblast activation and function.The neonatal rat cardiac fibroblasts were isolated and cultured.First,transforming growth factor β1 (TGFβ1) was used to stimulate fibroblast activation.A decreased expression level of Bcl6 was observed in fibroblasts after stimulation with TGFβ1.Then,cells were transfected with adenovirus Bcl6 to overexpress Bcl6.The results showed that Bcl6 overexpression induced decreased proliferation and reduced activation of fibroblasts which were stimulated with TGFβ1.It was found that activated smad2 and smad3 were not changed by overexpressing Bcl6,but smad4 was decreased.Furthermore,co-immunoprecipitation results showed that Bcl6 directly bound to smad4,and induced down-regulation of smad4.At last,smad4 activator could counteract the anti-fibroblast effects of Bcl6.In conclusion,Bcl6 may negatively regulate cardiac fibroblast activation and function by directly binding to smad4.

Cytotoxicity and genome-wide microarray analysis of intestinal smooth muscle cells in response to hexavalent chromium induction

Chronic ingestion of high concentrations of hexavalent chromium[Cr(VI)]in drinking water induces intestinal tumors in mice;however,information on its toxicity on intestinal smooth muscle cells is limited.The present study aimed to assess the in vitro and in vivo toxicological effects of Cr(VI)on intestinal smooth muscle cells.Human intestinal smooth muscle cells(HISM cells)were cultured with different concentrations of Cr(VI)to evaluate effects on cell proliferation ability,oxidative stress levels,and antioxidant system.Furthermore,tissue sections in Cr(VI)exposed rabbits were analyzed to evaluate toxicity on intestinal muscle cells in vivo.Gene chips were utilized to assess differential gene expression profiles at the genome-wide level in 1μmol/L Cr(VI)treated cells.Intestinal tissue biopsy results showed that Cr(VI)increased the incidences of diffuse epithelial hyperplasia in intestinal jejunum but caused no obvious damage to the structure of the muscularis.Cell proliferation analysis revealed that high concentrations(≥64μmol/L)but not low concentrations of Cr(VI)(≤16μmol/L)significantly inhibited the growth of HISM cells.For oxidative stress levels,the expression of reactive oxygen species(ROS)and nitric oxide(NO)was elevated at high concentrations(≥64μmol/L)but not at low concentrations of Cr(VI)(≤16μmol/L).In addition,dose-dependent increases in the activity of oxidized glutathione(GSSH)/total-glutathione(T-GSH)were also observed.Gene chip screened 491 differentially expressed genes including genes associated with cell apoptosis,oxidations,and cytoskeletons.Some of these differentially expressed genes may be unique to smooth muscle cells in response to Cr(VI)induction.

Forest carbon storage in Guizhou Province based on field measurement dataset

Accurate estimation of forest carbon storage is crucial in understanding global and regional carbon cycles and projecting future ecological and economic scenarios.Guizhou is the largest karst landform province in China;61.9% of its land area is characterized as karst. However,monitoring its field biomass and carbon storage is difficult.This study synthesized and analyzed a comprehensive database of direct field observations of forest vegetation and soil carbon storage in Guizhou Province by using data from existing literature. The total vegetation carbon storage in Guizhou Province was 488.170 TgC, the average vegetation carbon density(VCD) was 27.866 MgC hm^(-2), the total amount of soil organic carbon(SOC)(20 cm) was 1017.364 TgC, and the average SOC density was 58.074 MgC hm^(-2). Among all vegetation types, needleleaf forest had the highest vegetation carbon stocks, and scrub presented the highest SOC storage. The vegetation and SOC storage values of the karst landform were 282.352 and 614.825 TgC, respectively, which were higher than thoseof the non-karst landform. VCD was concentrated at 10–40 MgC hm^(-2), and SOC density was concentrated at 40–60, 60–80, and 80–100 MgC hm^(-2). This comprehensive regional data synthesis and analysis based on direct field measurement of vegetation and soil will improve our understanding of the forest carbon cycle in karst landforms under a changing climate.

Cytotoxicity and genome-wide microarray analysis of intestinal smooth muscle cells in response to hexavalent chromium induction

Chronic ingestion of high concentrations of hexavalent chromium [Cr（VI）] in drinking water induces intestinal tumors in mice; however, information on its toxicity on intestinal smooth muscle cells is limited. The present study aimed to assess the in vitro and in vivo toxicological effects of Cr（VI） on intestinal smooth muscle cells. Human intestinal smooth muscle cells （HISM cells） were cultured with different concentrations of Cr（VI） to evaluate effects on cell proliferation ability, oxidative stress levels, and antioxidant system. Furthermore, tissue sections in Cr（VI） exposed rabbits were analyzed to evaluate toxicity on intestinal muscle cells in vivo. Gene chips were utilized to assess differential gene expression profiles at the genome-wide level in 1 gmol/L Cr（VI） treated cells. Intestinal tissue biopsy results showed that Cr（VI） increased the incidences of diffuse epithelial hyperplasia in intestinal jejunum but caused no obvious damage to the structure of the muscularis. Cell proliferation analysis revealed that high concentrations （〉__64 gmol/L） but not low concentrations of Cr（VI） （〈16 ~tmol/L） significantly inhibited the growth of HISM cells. For oxidative stress levels, the expression of reactive oxygen species （ROS） and nitric oxide （NO） was elevated at high concentrations （〉64 pmol/L） but not at low concentrations of Cr（VI） （〈16 pmol/L）. In addition, dose-dependent increases in the activity of oxidized glutathione （GSSH）/total-glutathione （T-GSH） were also observed. Gene chip screened 491 differentially expressed genes including genes associated with cell apoptosis, oxidations, and cytoskeletons. Some of these differentially expressed genes may be unique to smooth muscle cells in response to Cr（VI） induction.

Impact of IL-18 gene promoter polymorphisms on renal cell carcinoma occurrence and prognosis in Chinese Han population

Objective Genetic polymorphisms in various inflammatory cytokines have been associated with the risk and growth or invasiveness of renal cell carcinoma(RCC).However,the molecular basis of RCC pathogenesis is unclear.The aim of this study was to explore a possible association between two IL-18 gene promoter polymorphisms,-137G/C and -607 C/A,and RCC occurrence and prognosis in a Chinese Han population.Methods Chinese Han patients with RCC(n=175) and age-matched healthy controls(n=200) were analyzed by single nucleotide polymorphism genotyping during follow-up.Results IL-18-137G allele frequency was significantly higher in patients with lymph node metastasis(Odds ratio [OR],3.52;95% confidence interval [CI],0.97-16.17;P=0.045).The IL-18-607 CC genotype was associated with distant metastasis(OR,2.81;95% CI,1.35-6.24;P=0.025).The IL-18-137G allele was correlated with more advanced tumor stage(OR,1.83;95% CI,1.05-3.72;P=0.026) and higher tumor grade(OR,2.23;95% CI,0.78-4.12;P=0.041).The IL-18-607 CC genotype frequency was significantly higher in patients with more advanced cancer stage(OR,2.92;95% CI,1.80-6.87;P=0.001) and higher tumor grade(OR,2.21;95% CI,1.25-12.25;P=0.035).The IL-18-607 allele was associated with more advanced cancer stage(OR,2.47;95% CI,1.38-3.83;P=0.002).Carriers of the GG genotype with the -137G/C polymorphism had a 2.165-times higher risk of RCC progression than carriers of the GC genotype(Hazard ratio=2.15,95% CI,1.270-3.687).Conclusion The IL-18-137G allele was correlated with more advanced stage,higher tumor grade,and lymph node metastasis.IL-18 gene promoter polymorphism -137G/C may thus influence the prognosis of RCC patients.

Regional features of pollen R-values in China

Establishing a quantitative relationship between modern pollen and vegetation remains a pivotal but intricate pursuit within the field of Quaternary palynology.The R-value,a well-established and traditional metric characterized by its simplicity and direct applicability,serves to calibrate the nonlinear disparities between surface pollen and modern vegetation.This study entails the construction of a comprehensive pollen R-value dataset for China derived from R-values published between 1987 and 2021.The dataset,compiled after rigorous screening,calibration,and standardization processes,encompasses 898 modern pollen sampling sites and 2115 pollen R-value data entries,encapsulating 152 pollen taxa spanning 65 families and 113 genera.Synthesizing the extracted R-values yielded the following insights:(1)A macrospatial analysis validates previously established knowledge at a site-specific scale.Evidently,pollen R-value variations across China are statistically significant.Approximately two-thirds of pollen taxa exhibit underrepresentation(e.g.,Taxodiaceae,Corylus,Nitraria,Tamarix,Cyperaceae,Poaceae,and Fabaceae),while the remaining one-third display overrepresentation(e.g.,Pinus,Picea,Betula,Ephedra,Chenopodiaceae,and Artemisia).The degree of underrepresentation surpasses that of overrepresentation,and the representation patterns of Castanea,Quercus,Polygonaceae,and Asteraceae are contingent upon vegetation types.(2)Pollen R-values follow distinct spatial distribution patterns within China.In the woody vegetation region of eastern China,R-values progressively decline from north to south,correlating with rising temperatures and precipitation.Conversely,in herbaceous vegetation regions of northern and western China,R-values decrease from east to west and from northeast to southwest,corresponding to increased aridity.Nevertheless,pollen R-values manifest variation contingent on pollen taxa,vegetation types,and climatic regions,even differing for the same taxa across varying vegetation types and climatic conditions.This highlights the intricate nature of pollen R-values and their interpretation of pollen-vegetation relationships.(3)Pollen R-values and relative pollen production estimates exhibit resemblances and a modest positive correlation.However,adjudicating between them as representatives of vegetation requires nuanced consideration,as both metrics convey pollen representation within vegetation,demonstrating the multifaceted relationships they share with modern vegetation.Further recommendations suggest that when assessing pollen representation in modern vegetation,fossil pollen content should be weighted using either the median or log-transformed R-value.This approach underscores the necessity of comprehensively accounting for divergences and convergences across various spatial scales and vegetation types,particularly the disparities observed within identical pollen taxa across dissimilar regions.