Search

The main component of the gas in the fish storage tank is hydrogen sulfide. Hydrogen sulfide poisoning is a common occupational chemical poisoning among fishermen in summer, and acute hydrogen sulfide poisoning can manifest as toxic encephalopathy. This paper analyzes a patient with delayed encephalopathy suspected of acute hydrogen sulfide poisoning. The patient was unconscious for 18 days after waking up for 5 days after acute hydrogen sulfide poisoning. After waking up again, there were symptoms such as decreased limb muscle strength, ataxia, swallowing, dysarthria, and the clinical characteristics were significantly different from those of delayed encephalopathy caused by acute carbon monoxide poisoning, such as decreased cognitive function and damage to extrapyramidal system.储鱼舱气体的主要成分是硫化氢，硫化氢中毒是夏季渔民常见的职业性化学中毒，而急性硫化氢中毒可表现为中毒性脑病。本文对1例疑似急性硫化氢中毒所致迟发性脑病患者进行分析，患者在发生急性硫化氢中毒清醒5 d后，昏迷18 d；再次清醒后，出现四肢肌力下降、共济失调并吞咽、构音困难等症状，其临床特点与急性一氧化碳中毒迟发性脑病表现为认知功能下降及锥体外系受损有明显不同。.

Prostate cancer (PCa) is one of the most diagnosed cancers in men worldwide. Several studies have identified that circular RNAs (circRNAs) have a crucial impact on the biological processes in PCa. Therefore, it is necessary to study the molecular mechanism of circRNAs in tumor progression and metastasis. RNA interference was used to decrease circHIPK3 and MTDH expression. Overexpression vector was used to increase circHIPK3 and MTDH expression. Luciferase reporter assay were used to detect the relationship between circHIPK3 and miR-448 or between miR-448 and MTDH. MTT assay, colony formation assay and transwell assay were used to measure proliferation and migration of PCa cells. Circular RNA circHIPK3 was significantly increased in PCa tissues and cell lines. And overexpression of circHIPK3 promoted the migration, proliferation, and invasion of PC-3 and 22Rv1 cells, while knockdown of circHIPK3 markedly repressed the above-mentioned series of biological processes. Furthermore, circHIPK3 promoted metadherin (MTDH) expression by sponging miR‐448. In vivo experiments, it was also found that overexpression of circHIPK3 significantly promoted tumor growth. Our research shows that circHIPK3 plays a carcinogenic effect in PCa by regulating the miR-448/MTDH axis, indicating that circHIPK3 may be a potential therapeutic target for PCa.

Prostate cancer (PCa) is one of the most diagnosed cancers in men worldwide. Several studies have identified that circular RNAs (circRNAs) have a crucial impact on the biological processes in PCa. Therefore, it is necessary to study the molecular mechanism of circRNAs in tumor progression and metastasis.RNA interference was used to decrease circHIPK3 and MTDH expression. Overexpression vector was used to increase circHIPK3 and MTDH expression. Luciferase reporter assay were used to detect the relationship between circHIPK3 and miR-448 or between miR-448 and MTDH. MTT assay, colony formation assay and transwell assay were used to measure proliferation and migration of PCa cells.Circular RNA circHIPK3 was significantly increased in PCa tissues and cell lines. And overexpression of circHIPK3 promoted the migration, proliferation, and invasion of PC-3 and 22Rv1 cells, while knockdown of circHIPK3 markedly repressed the above-mentioned series of biological processes. Furthermore, circHIPK3 promoted metadherin (MTDH) expression by sponging miR-448. In vivo experiments, it was also found that overexpression of circHIPK3 significantly promoted tumor growth.Our research shows that circHIPK3 plays a carcinogenic effect in PCa by regulating the miR-448/MTDH axis, indicating that circHIPK3 may be a potential therapeutic target for PCa.

To explore the correlation between angiotensin II type 1 receptor (AT1R) gene polymorphism and epilepsy secondary to cerebral infarction and its significance for the diagnosis of this disease.A total of 200 patients with epilepsy secondary to cerebral infarction were enrolled from our hospital as observation group, and 200 patients without epilepsy after cerebral infarction as control group. Genomic deoxyribonucleic acids (DNAs) were extracted from the peripheral blood of the subjects, and the polymorphic regions at AT1R gene loci rs380400, rs1799870, rs12721273, and rs55707609 were amplified via polymerase chain reaction (PCR) and sent to the company for sequencing. The concentration of farnesyl diphosphate synthase (FDPS) was determined using enzyme-linked immunosorbent assay (ELISA) kit, and activated partial thromboplastin time (APTT) and prothrombin time (PT) were measured in the Laboratory Department.There were no differences in the allele distributions at AT1R gene loci rs380400 (p=0.070), rs179987 (p=0.0.280), and rs55707609 (p=0.046), but in the allele distribution at rs12721273 (p=0.001) between control group and observation group, and observation group exhibited a significantly lower frequency of allele G in cerebral infarction patients than control group [153 (0.383) vs. 198 (0.495)]. The frequency of genotype GT at rs12721273 was lower [71 (0.355)] and that of genotype TT was evidently higher [88 (0.440)] in observation group (p=0.000). Control group showed a notably lower frequency of genotype AA [47 (0.235)] and a markedly higher frequency of genotype AT [110 (0.550)] at rs55707609 (p=0.000). Observation group exhibited a substantially lower frequency of recessive model AG+GG [128 (0.640)] (p=0.037), and a notably higher frequency of homozygous model AA [72 (0.360)] (p=0.048) at AT1R gene locus rs380400, a remarkably lower frequency of dominant model GG+GT [112 (0.560)] (p=0.002) at rs12721273, and a significantly lower frequency of recessive model AT+TT [126 (0.630)] (p=0.000) and a considerably lower frequency of heterozygous model AT [84 (0.420)] (p=0.026) at rs55707609. The frequencies of AT1R gene haplotypes ACGA (p=0.001), ACGT (p=0.045), ACTT (p=0.000), ATTT (p=0.048), GCTA (p=0.000), and GTGA (p=0.005) in observation group were distinctly higher than those in control group, and the frequencies of the haplotypes ACTA (p=0.000) and ATTA (p=0.029) were evidently lower than those in control group. The loci rs12721273 and rs1799870 showed a significant association (D'=0.783), and APTT was considerably correlated with genotype AG at rs380400 (p=0.042), PT with genotype CC at rs1799870 (p=0.002) and FDPS with genotype AA at rs55707609 (p=0.015).The polymorphisms of AT1R gene loci rs380400, rs1799870, rs12721273, and rs55707609 are correlated with the susceptibility to epilepsy secondary to cerebral infarction.

Several long noncoding RNAs (lncRNAs) display functional effects in the tumorigenesis and progression of cervical cancer (CC). We aimed to investigate the roles of lncRNA tyrosine protein kinase transmembrane receptor 1 antisense RNA 1 (ROR1‑AS1) in the development of CC patients.Reverse Transcription-Polymerase Chain Reaction (RT-PCR) was performed for the determination of ROR1‑AS1 levels in both CC tissues and cell lines. The clinical value of ROR1‑AS1 expression in CC patients was statistically analyzed. After transfection with si-ROR1‑AS1 in SiHa and HeLa cells, cellular growth and apoptosis were examined by Cell Counting Kit (CCK-8) assay, cell colony formation, and flow cytometry. Then, wound-healing assays and transwell assays were performed to evaluate cell migration and invasion, respectively. The related proteins of epithelial-mesenchymal transition (EMT) markers and Wnt/β-catenin signaling pathway was assessed using Western blot assays.We found that that the expressions of ROR1‑AS1 were distinctly increased in CC tissues and cell lines. Clinical study revealed that high ROR1‑AS1 expression was associated with distant metastasis, FIGO stage, and shorter five-year survival. Functional assays by performing in vitro assays revealed that inhibition of ROR1‑AS1 distinctly suppressed CC cell proliferation, colony formation, migration and invasion, and promoted apoptosis. Based on results of Western blot, we showed that the downregulation of ROR1‑AS1 inhibited the levels of N-cadherin and vimentin. In addition, the distinctly decreased levels of c-myc, β-catenin, and cyclin D1 were observed in CC cells transfected with si-ROR1‑AS1.Our results suggest that ROR1‑AS1 is likely to serve as an efficient therapeutic approach in respect of CC treatment. Our results suggest that KLF5 may be a potential therapeutic target in laryngeal carcinoma.

High-efficiency flexible solar modules are fabricated with thin-film GaAs solar cells to satisfy the demand for power generation systems of unmanned aerial vehicles (UAVs) and stratospheric airships. The polyimide substrate inverted metamorphic triple junction (IMM 3J) GaAs thin-film solar cells are interconnected using the electrically conductive films by low temperature hot press welding technology, and the solidity of welding and efficiency loss ratio of the cells reach the level of rigid GaAs triple junction solar cells used in space now. Two different size solar cells are integrated and encapsulated separately using the thermo-sensitive adhesive supporting films to achieve a good laminating performance. The 0.2 m2 flexible module consisting of unfilled corner cells has the specific power over 750 W/kg (AM0, 1353 W/m2), and the 0.5 m2 flexible module consisting of rectangle cells has higher specific power over 800 W/kg benefit from a higher cell-to-module ratio (CTM). The two modules have an areal density of less than 500 g/m2. Several near space reliability tests have been done to verify that the flexible solar modules could meet the special environment application need.

Aberrant activation of the JAK3-STAT signaling pathway is a characteristic feature of many hematological malignancies. In particular, hyperactivity of this cascade has been observed in natural killer/T-cell lymphoma (NKTL) cases. Although the first-in-class JAK3 inhibitor tofacitinib blocks JAK3 activity in NKTL both in vitro and in vivo, its clinical utilization in cancer therapy has been limited by the pan-JAK inhibition activity. To improve the therapeutic efficacy of JAK3 inhibition in NKTL, we have developed a highly selective and durable JAK3 inhibitor PRN371 that potently inhibits JAK3 activity over the other JAK family members JAK1, JAK2, and TYK2. PRN371 effectively suppresses NKTL cell proliferation and induces apoptosis through abrogation of the JAK3-STAT signaling. Moreover, the activity of PRN371 has a more durable inhibition on JAK3 compared to tofacitinib in vitro, leading to significant tumor growth inhibition in a NKTL xenograft model harboring JAK3 activating mutation. These findings provide a novel therapeutic approach for the treatment of NKTL.

目的 探索MRI早期诊断和评估骨髓增生异常综合征（MDS）患者体内脏器铁过载的价值。 方法 以2014年11月至2018年1月期间接受过MRI横向弛豫时间（T2*）检查（包括心和肝）的确诊为铁过载的85例MDS患者为研究对象，同时进行心脏超声检测获得左心室射血分数（LVEF），收集血清铁蛋白（SF）、肝脏谷丙转氨酶（ALT）、B型脑钠肽前体（proBNP）指标。其中有7例低/中危-1的MDS患者在2次MRI检查期间接受了规律去铁治疗6个月，除上述指标外，还收集去铁前后相应的外周血细胞计数、转铁蛋白饱和度（TS）、肝脏谷草转氨酶（AST）进行比较。 结果 研究对象心脏T2*与年龄（rs=−0.290，P=0.007）、LVEF（rs=0.265，P=0.009）间存在相关性，其中有输血史的患者心脏T2*与输血量呈明显负相关（rs=−0.701，P0.05），LIC与年龄也无明显相关性（P值均>0.05）。LVEF是否正常组间心脏T2*值升高有统计学意义（P=0.005），但心脏铁过载比例（T2*15 mg/g DW）有统计学意义（P=0.045）。7例去铁治疗后患者SF、TS、ALT、AST、proBNP、LIC均比去铁治疗前降低，外周血细胞水平较治疗前升高。但LVEF和心脏T2*去铁治疗后的改变不明显。 结论 心脏T2*及LIC对MDS患者脏器铁过载评估有早期预测性，比同期的LVEF、SF及其他实验室指标更有价值，可作为脏器铁过载患者较为理想的早期检测和去铁治疗疗效评估手段。

To establish a mouse lymphoma xenograft model so as to investigate the correlation between the expression of matrix metallopeptidase-9 (MMP-9) and that of B-cell lymphoma 2 (Bcl-2) in lymphomas.Diffuse large Bcl (DLBCL) cells were cultured, and a mouse lymphoma xenograft model was established via the subcutaneous injection. Mouse lymphoma tissues were extracted, and the expressions of MMP-9 and Bcl-2 messenger ribonucleic acids (mRNAs) in the xenograft tumor were detected using Real-time polymerase chain reaction (PCR). Immunohistochemistry was used to detect the expression levels of MMP-9 and Bcl-2 proteins in lymphoma tissues and tumor-adjacent tissues. The consistency of MMP-9 expression and Bcl-2 expression was analyzed via Spearman's rank correlation analysis.The expressions of MMP-9 and Bcl-2 in lymphoma tissues were increased. The expression levels of MMP-9 and Bcl-2 proteins in lymphoma tissues were higher than those in tumor-adjacent tissues. The expression levels of MMP-9 and Bcl-2 were correlated with the body weight loss degree of mice, and the expression of MMP-9 was positively associated with that of BCL-2 in lymphomas.MMP-9 and Bcl-2 are associated with the onset of DLBCL, and they are potential impact factors affecting the prognosis.

A Cr(III) contained conversion coating on AA2024-T3 was prepared in solution containing Cr2(SO4)3 and K2ZrF6. Its composition was analysed using X-ray photoelectron spectroscopy, and its corrosion resistance was characterised by electrochemical measurements and neutral salt spray exposure. To investigate its self-repairing effect, the coupling current between a small uncoated sample and a large coated sample was monitored through an artificial scratch cell. The coating mainly consists of zirconium oxide and chromium oxide and hydroxide; no Cr(VI) species is detected. It improves the corrosion resistance by hindering the anodic process as well as the cathodic process. Meanwhile, it possesses self-repairing effect, which is generated from the release of Cr(III) species from the coating, migration and then deposition on the nearby scratch area.

To investigate the possible function and mechanism of lncRNA SNHG8 in the pathogenesis of endometrial carcinoma.We utilized qRT-PCR to detect the expression of SNHG8 in 60 cases of endometrial carcinoma and 25 cases of normal endometrium; after that, the endometrial carcinoma cell lines were screened. SNHG8 was transfected into endometrial carcinoma cells by Lipofectamine and the proliferative activity of cells was detected by cell counting kit-8 (CCK-8) assay. Bioinformatics methods were used to detect the target microRNA. miR-152 is predicted to bind to SNHG8 and target genes of c-MET. Luciferase reporter assay was performed to detect the relative luciferase activity between miR-152 and c-MET, SNHG8. The interactions between SNHG8, miR-152, and c-MET were further verified by transfection of miR-152 mimics, miR-152 mimics + OE-SNHG8, SNHG8 siRNA, and SNHG8 siRNA + miR-152 inhibitor.SNHG8 expression in endometrial carcinoma tissue was significantly higher than that in normal endometrium. After transfection with SNHG8 siRNA, the cell viability of AN3CA cells decreased, whereas the activity of Ishikawa was increased after transfection with SNHG8 overexpression plasmid. Bioinformatics predictions and dual luciferase reporter assay illustrated that SNHG8 was bound to miR-152 and miR-152 targeted on c-MET. In addition, miR-152 mimics inhibited the expression of c-MET, and the inhibitory effect was reversed after SNHG8 overexpression. Silencing SNHG8 reduced c-MET expression, and c-MET expression was reversed after addition of miR-152 inhibitor.SNHG8 is highly expressed in endometrial carcinoma, and SNHG8 targets c-MET through miR-152 to regulate the proliferation of endometrial cancer cells.

目的 探索预测骨髓增生异常综合征（MDS）及相关肿瘤地西他滨治疗反应的临床及分子学指标。 方法 回顾性分析109例接受地西他滨治疗的MDS及相关肿瘤患者临床资料，采用二代测序检测MDS常见突变基因的突变情况，分析患者临床特征及基因突变与地西他滨临床反应的关系。 结果 地西他滨中位疗程数为4（2~11）个，共74例（67.9%）患者获得治疗反应，其中30例（27.5%）获得完全缓解（CR）；35例（32.1%）患者无反应。单因素分析结果显示，国际预后积分系统（IPSS）中危2+高危、复杂核型、单体核型、7号染色体异常及1个疗程后PLT倍增的患者可获得更高的CR率。66.7%（14/21）的复杂核型患者、58.8%（10/17）的单体核型患者及66.7%（10/15）的TP53基因突变患者获得CR；TP53基因突变常合并复杂核型及单体核型；多因素分析显示TP53突变、1个疗程后PLT倍增及复杂核型是预测地西他滨治疗获得CR的独立预后因素，其中TP53突变是最强的预测因子（OR=4.39，95%CI 1.20~16.06，P=0.026）。 结论 TP53基因突变、1个疗程后PLT倍增及复杂核型可预测地西他滨完全缓解。

As part of the PRIDE-PRD2006 intensive campaign, atmospheric boundary layer (ABL) measurements were performed in Qingyuan, Panyu, and Xinken over the Pearl River Delta (PRD) on 1–30 July 2006. During the summer, the surface winds over the PRD are generally controlled by the south, usually with vertical wind shear at a height of approximately 800 m. Subsidence and precipitation from a tropical cyclone affects the air quality of the PRD. Under subsidence, wind speed in the ABL and the height of the ABL decrease and result in high-level concentrations. When the background wind speed is small or calm, the wind profile in Panyu and Xinken changes dramatically with height, which is perhaps caused by local circulation, such as sea-land breezes. To better understand the ABL of the PRD, simulations that used the Weather Research and Forecasting (WRF) mesoscale model were utilized to analyze the ABL characteristics over the PRD. Based on three types of weather condition simulations (i.e., subsidence days, rainy days, and sunny days), the WRF model revealed that the simulated temperature and wind fields in these three cases were moderately consistent with the measurements. The results showed that diurnal variations of the ABL height on subsidence days and sunny days were obvious, but diurnal variations of the ABL height on rainy days were not apparent. The ABL is obviously affected by local circulation, and the ABL features are different at various stations. A simulation focused on a high pollution episode during the subsidence days on 12–15 July 2006, occurred under high-pressure conditions, accompanied by the tropical cyclone "Bilis". A comparison of the simulated vertical wind fields and temperature structure with the ABL measurements at Xinken, Panyu, and Qingyuan stations found that the modeled and measured atmospheric fields revealed two different types of ABL characteristics over the PRD. When the surface winds over the PRD were light or nearly calm, the local circulation dominated, such as the sea-land breeze at Xinken station and the mountain-valley circulation at Qingyuan station. When the surface winds were strong, the stations were under the same background weather system, and the wind directions were almost the same. Furthermore, the modeled results also suggest that the subsidence by the typhoon "Bilis" had a great impact on the high Air Pollution Index (API).

Freshly harvested loquat (Eriobotrya japonica Lindl. 'Dahongpao') fruit were exposed to 100% N 2 for 6h at 20°C and then stored at 5°C for 35 days to investigate the effect of short-term N 2 treatment on the quality of the fruit. Fruit decay rate, total soluble solids (TSS) and total titratable acidity (TA) contents, membrane permeability, malondialdehyde (MDA) content were measured. The short-term N 2 treatment significantly delayed the increase of fruit decay rate and delayed the decreases of total soluble solids (TSS) and total titratable acidity (TA) contents, thereby maintaining better eating quality and extending the storage life of the fruit. The short-term N 2 treatment also markedly delayed the increases in membrane permeability, malondialdehyde (MDA) content. These results suggest that a prestorage pure N 2 treatment for 6h can effectively reduce fruit decay, delay the peroxidation of membrane lipid and maintain the quality of loquat fruit. Therefore, a short-term N 2 treatment in combination with low temperature could be a useful technique to maintain the quality of postharvest loquat fruit.

SummaryThe effects of exogenous ethylene on the flower quality and the influence of cold storage on the ethylene sensitivity of cut Asiatic hybrid lilies ‘Brussels’ were investigated. Treatment of freshly-harvested cut lilies with 4 × 10–3 mol l–1 ethephon increased the percentage of flower abscission and bud abortion, but reduced flowering percentage and flower diameter. Pretreatment with 2 × 10–3 mol l–1 STS prior to ethephon exposure completely reversed the effect of 4 × 10–3 mol l–1 ethephon on flower abscission percentage, bud abortion percentage, flowering percentage, floral diameter, vase life and floral longevity. Data thus indicated that freshly-harvested cut ‘Brussels’ lilies were sensitive to ethylene. In comparison, application of 4 × 10–3 mol l–1 ethephon to cold-stored cut lilies did not induce flower abscission or bud abortion. Nor did this treatment influence flowering percentage, flower diameter and floral longevity. Pretreating cold-stored stems with 2 × 10–3 mol l–1 STS before ethephon ...

Electronic transport properties of carbon dumbbells, a new type of carbon hybrid nanostructures formed by connecting carbon atomic chains to two fullerenes C(60), are investigated by using nonequilibrium Green's functions in combination with the density-functional theory. Specifically, the transport properties as a function of the carbon chain length n are examined. An obvious metal-insulator-like oscillation has been achieved with the increase of the carbon chain length. When n is even, the device behaves as a metal. In contrast, when n is odd, it behaves as an insulator. It is quite different to the carbon chains directly sandwiched between metallic leads where the low conductance states are observed for even n while the high conductance states are observed for odd n. Such a difference arises from the screening effect of C(60)s.

Steroid 21-hydroxylase deficiency (21-OHD) is the most common cause of congenital adrenal hyperplasia (CAH). Clinically, 21-OHD is categorized into saltwasting, simple-virilizing (SV), and non-classical (NC) forms. It is well recognized that a good correlation exists between genotype and clinical phenotype of CAH.The aim of this study was to identify CYP21A2 gene mutations in 2 Chinese patients with SV CAH along with their parents and other family members.By direct sequencing the CYP21A2 gene, a novel mutation, P459H, was detected in 1 patient; and a previously described uncharacterized mutation, R483W, was found in another patient. The 21-hydroxylase activities were determined by measuring the converting rate of progesterone to 11-deoxycorticosterone in COS-7 cells overexpressed with these mutated proteins. Our results revealed significantly reduced enzyme activity in both mutants: residual activity of P459H and R483W towards progesterone was 6.8%±2.1 and 2.9%±1.5, respectively compared to that of the wild type. We also demonstrated the loss of 21-hydroxylase activities using a three-dimensional model of CYP21A2.Both R483W and P459H mutations are confirmed to be related to NC CAH by in vitro functional study, with phenotype variance of R483W in Tunisian and Chinese patients. This study will aid in predicting disease severity and in facilitating family genetic counseling.

Atmospheric conditions are often connected with the occurrence of high pollution episodes especially in urban areas. As part of the PRIDE-PRD2006 intensive campaign, atmospheric boundary layer (ABL) measurements were carried out at Qingyuan, Panyu and Xinken in the Pearl River Delta (PRD) from 1 July to 30 July of 2006. It was found that in summer, the surface winds in PRD are more controlled by the south, and there usually is vertical wind shear at the height of 800 m or so, therefore, PRD is often influenced by the tropical cyclone/typhoon. The subsidence and precipitation from a tropical cyclone will affect the air quality of PRD. Under the subsidence, the wind speed in ABL and the height of ABL will decrease and result in high level concentrations. When the background wind speed is small or calm, the wind profile at Panyu and Xinken change dramatically with height, which is perhaps caused by the local circulations, such as the sea land breeze. For more understanding about the ABL of PRD, the simulations by the WRF mesoscale model were used to analyse the ABL characteristics in PRD. From three kinds of weather condition simulations (subsidence days, rainy days and sunny days) by WRF model, it was found that the simulated temperature, wind fields in these three cases were moderately consistent with the measurements. The results show that the diurnal variation of ABL in subsidence days and sunny days are obvious, but the diurnal variation of ABL on rainy days is not obvious. The ABL is obviously affected by the local circulation and the features of ABL are different in various stations. A simulation focus on high pollution episode during the subsidence days from 12–15 July 2006, occurred under high pressure conditions, accompanied by a tropical cyclone "Bilis". Comparing the simulated vertical wind fields and temperature structure with the ABL measurements at Xinken, Panyu and Qingyuan station, it was found that, the modelled and measured atmospheric fields reveal that there are two different kinds of ABL characteristics in PRD: when the surface winds in PRD were light or almost calm, the local circulation was dominated, such as the sea-land breeze at Xinken station and the mountain-valley circulation at Qingyuan station. When the surface winds were strong, the stations were under the same background weather system and the wind directions were almost the same. Furthermore, the modelled results also suggest that the high Air Pollutant index (API) episode was caused predominately by subsidence.

Cancer chemopreventive effects of organic extracts from 29 species of lichens collected in Iceland were evaluated using a panel of in vitro bioassays whereby extracts were tested for potential to induce quinone reductase (QR) and differentiation of human promyelocytic leukemia (HL-60) cells, inhibit cyclooxygenase-1 (COX-1), phorbol ester-induced ornithine decarboxylase (ODC), aromatase and sulfatase, as well as for antioxidant, estrogenic/anti-estrogenic and antiproliferative activity. In addition, the extracts were tested for cytotoxicity against 12 cancer cell lines. The most significant results were exhibited by extracts from Xanthoria elegans and Alectoria nigricans , which respectively, induced QR activity (concentration to double activity = 4.8 µg/ml) and inhibited phorbol ester-induced ODC activity with mouse 308 cells in culture (IC 50 = 2.6 µg/ml). Moderate inhibition of [ 3 H]thymidine incorporation with HL-60 cells was exhibited by the Peltigera leucophlebia extract. Several extracts prevented estrogen formation from estrogen precursors by inhibiting the enzymatic activities of aromatase ( Sphaerophorus globosus , Cetrariella delisei , Melanelia hepatizon ) and sulfatase ( Cladonia gracilis , Sphaerophorus fragilis , S. globosus ). None of the extracts demonstrated significant cytotoxic effects with selected cell lines.

To study the effects of estradiol (Est) on inward rectifier K+ (IK1) and delayed rectifier K+ (IK) channels in isolated guinea pig ventricular myocytes.Using whole cell patch-clamp recording techniques.Est 10 mumol.L-1 and 100 mumol.L-1 decreased the action potential duration, APD50, from (474 +/- 71) ms to (330 +/- 75) ms and (229 +/- 67) ms (n = 7 cells of 7 guinea pigs, P0.05), respectively. Est 100 mumol.L-1 also decreased APD90 from (587 +/- 60) ms to (418 +/- 79) ms (n = 7, P0.05). Est inhibited IK tail current (IK.tail) concentration-dependently. IK.tail was depressed 53% (n = 5, P0.05) at 10 mumol.L-1 and 80% (n = 5, P0.01) at 100 mumol.L-1 compared with control. Estor = 10 mumol.L-1 blocked IK1. The maximal inhibition of inward current of IK1 occurred at -100 mV test potential was 49% (n = 5, P0.01) and outward current of IK1 at -40 mV was 72% (n = 5, P0.01). The reverse potential shifted negatively, from -70 to -76 mV.Est possessed blocking effects on both IK1 and IK channels in guinea pig ventricular myocytes.

To study the effects of sex hormones, estradiol (Est), progesterone (Pro) and testosterone (Tes) on the action potential (AP) and contraction of guinea pig papillary muscle.Using conventional glass microelectrode and mechanical recording of myocardial contraction.Est slowed down the maximal rate of rise of phase 0 (Vmax) of AP at low concentration (1 mumol.L-1). At 10 mumol.L-1 and above, Est also prolonged AP duration (APD50 and APD90), effective refractory period (ERP) and decreased the maximal isometric tension (Pmax) and velocity of tension development (dT/dt) of contraction. Tes (100 mumol.L-1 - 1 mmol.L-1) prolonged APD90 and ERP with decreased Pmax and dT/dt. But Pro (1 mumol.L-1 - 1 mmol.L-1) had no effects on both AP and contraction.Est prolonged AP and depressed contraction of guinea pig papillary muscle.

Induction of phase II enzymes is an important mechanism of chemoprevention. In our search for novel cancer chemopreventive agents, 4'-bromoflavone (4'BF) was found to significantly induce quinone reductase (QR) activity in cultured murine hepatoma 1c1c7 cells (concentration to double activity: 10 nM) and effectively induce the alpha- and mu-isoforms of glutathione S-transferase in cultured H4IIE rat hepatoma cells with no observed toxicity. In short-term dietary studies, 4'BF was also shown to increase QR activity and glutathione levels in rat liver, mammary gland, colon, stomach, and lung in a dose-dependent manner. Induction mediated by 4'BF was bifunctional (induction of both phase I and phase II enzymes) and regulated at the transcriptional level, as revealed by transient transfection studies with plasmid constructs (pDTD-1097CAT, XRE-CAT, and ARE-CAT) and reverse transcription-PCR-based analysis of QR mRNA. In studies conducted with female Sprague Dawley rats, the effects of 4'BF on the relative induction levels of phase I and phase II enzyme activities were investigated in liver and mammary gland. Treatment with 4'BF and 7,12-dimethylbenz[a]anthracene (DMBA) or 4'BF alone did not significantly alter DMBA-induced cytochrome P4501A1 activity (phase I enzyme), but it significantly increased QR activity (phase II enzyme), compared with the DMBA treatment group. In addition, 4'BF was found to be a potent inhibitor of cytochrome P4501A1-mediated ethoxyresorufin-O-deethylase activity, with an IC50 of 0.86 microM. Furthermore, in studies conducted with cultured HepG2 or MCF-7 cells, 4'BF significantly reduced the covalent binding of metabolically activated benzo[a]pyrene to cellular DNA. On the basis of these results, a full-term cancer chemoprevention study was conducted with DMBA-treated female Sprague Dawley rats. Dietary administration of 4'BF (2000 and 4000 mg per kg of diet, from 1 week before to 1 week after DMBA) significantly inhibited the incidence and multiplicity of mammary tumors and greatly increased tumor latency. In summary, 4'BF can be viewed as a relatively simple, readily available, inexpensive compound that is a highly effective cancer chemopreventive agent. The full mechanism of action remains to be defined, but enhancement of detoxification pathways appears to be important.

To study the effects of sodium pentobarbital (SP) on the action potential (AP) and contraction of guinea pig papillary muscle.Using conventional glass microelectrode and mechanical recording of myocardium contraction.SP (or = 10 mumol.L-1) prolonged the AP duration (APD) and effective refractory period (ERP), while amplitude (APA) and Vmax of phase 0 showed no changes. The effects of SP were abolished by pretreatment with cromakalim, an agonist of ATP-sensitive K+ channel. The maximal isometric tension (Pmax) and velocity of tension development (dT/dt) were decreased to 51% and 48% of control, respectively. The first postrest beat (B1) and second postrest beat (B2) were also depressed.SP affected the action potential by reducing activities of the K+ channels and reduced the contraction of guinea pig myocardium.

Folded graphene nanoribbons were observed and their unusual transport properties were reported recently. In this work, the electronic structures and the effects of external transverse electrical field in the folded zigzag-edged graphene nanoribbons (ZGNRs) are investigated by first-principles calculations. It is found that, the folding does not break the semiconductivity, the antiferromagnetically coupled edge states and edge magnetism characteristic of ZGNRs. Interestingly, when external electrical field is applied, the ribbons can be turned to metal or half-metal, depending on the direction of the field. The robustness of the half-metallicity and the edge magnetism to the electrical field is also discussed.

Zigzag-edged graphene nanoribbons (ZGNRs) are used to build devices in which transport with high spin polarization is realized by first-principles simulations. At first, we dope the semiconducting ZGNRs with B atoms on both sides to obtain a metallic ribbon. Then, in one segment of this ribbon which acts as the scattering region, the B atoms at one edge are substituted by C atoms or by N atoms. It is found that such devices show very good spin filtering effect which originates from the interaction between the impurity atoms and the edge states.