Effects of lead，cadmium，mercury chlorides and aquatic environmental samples on the growth of Escherichia coli

Ｅｆｆｅｃｔｓｏｆｌｅａｄ，ｃａｄｍｉｕｍ，ｍｅｒｃｕｒｙｃｈｌｏｒｉｄｅｓａｎｄａｑｕａｔｉｃｅｎｖｉｒｏｎｍｅｎｔａｌｓａｍｐｌｅｓｏｎｔｈｅｇｒｏｗｔｈｏｆＥｓｃｈｅｒｉｃｈｉａｃｏｌｉＸｕＣｈａｏ（ＤｅｐａｒｔｍｅｎｔｏｆＥｎｖｉｒｏｎｍｅｎ...

Chemopreventive and Growth Inhibitory Effects of Selenium

There is very convincing evidence that a high dietary level of selenium substantially reduces the incidence of a wide variety of animal cancers. The human epidemiological evidence is less clear cut, but overall suggests that selenium may be protective: the evidence is strongest in men in relation to gastro-intestinal cancers. There is evidence that dietary selenium compounds reduce the formation of DNA adducts by carcinogens. Selenium compounds also inhibit growth in vitro and induce apoptosis. In general, there is a good correlation between the effectiveness of selenium compounds in chemoprevention and growth inhibition, implying that the mechanisms of growth inhibition and chemoprevention may be similar and that a major factor in the chemopreventive effects of selenium compounds in vivo is their ability to retard outgrowth of pre-malignant cells. Various hypotheses have been advanced as to how selenium compounds might prevent tumour cellgrowth. One is that they cause apoptosis by inducing oxidative stress. However, we have shown that the most potent selenium compound, selenodiglutathione (SDG), a natural metabolite of selenite, does not induce oxidative stress, at least not in the sarne way as other oxidants such as H2O2 and diamide. Firstly, a partially selenium-resistant variant cell line does not show increased resistance to H2O2. Moreover, SDG does not induce widespread tyrosine phosphorylation, including MAP and SAN kinases, like other oxidants such as H2O2 and diamide and its effects are not reversed by pretreatment with the tyrosine kinase inhibitor, herbimycin. Our experiments with the selenium-resistant variant suggest that a novel selenium-binding protein may be involved in growth inhibition by selenium

Estimation of spectral responses and chlorophyll based on growth stage effects explored by machine learning methods

Estimation of leaf chlorophyll content(LCC) by proximal sensing is an important tool for photosynthesis evaluation in high-throughput phenotyping. The temporal variability of crop biochemical properties and canopy structure across different growth stages has great impacts on wheat LCC estimation, known as growth stage effects. It will result in the heterogeneity of crop canopy at different growth stages, which would mask subtle spectral response of biochemistry variations. This study aims to explore spectral responses on the growth stage effects and establish LCC models suited for different growth stages. A total number of 864 pairwise samples of wheat canopy spectra and LCC values with 216 observations of each stage were sampled at the tillering, jointing, booting and heading stages in 2021. Firstly, statistical analysis of LCC and spectral response presented different distribution traits and typical spectral variations peak at 470, 520 and 680 nm. Correlation analysis between LCC and reflectance showed typical red edge shifts. Secondly, the testing model of partial least square(PLS) established by the entire datasets to validate the predictive performance at each stage yielded poor LCC estimation accuracy. The spectral wavelengths of red edge(RE) and blue edge(BE) shifts and the poor estimation capability motivated us to further explore the growth stage effects by establishing LCC models at respective growth periods.Finally, competitive adaptive reweighted sampling PLS(CARS-PLS), decision tree(DT) and random forest(RF) were used to select sensitive bands and establish LCC models at specific stages. Bayes optimisation was used to tune the hyperparameters of DT and RF regression. The modelling results indicated that CARS-PLS and DT did not extract specific wavelengths that could decrease the influences of growth stage effects. From the RF out-of-bag(OOB) evaluation, the sensitive wavelengths displayed consistent spectral shifts from BE to GP and from RE to RV from tillering to heading stages. Compared with CARS-PLS and DT,results of RF modelling yielded an estimation accuracy with deviation to performance(RPD) of 2.11, 2.02,3.21 and 3.02, which can accommodate the growth stage effects. Thus, this study explores spectral response on growth stage effects and provides models for chlorophyll content estimation to satisfy the requirement of high-throughput phenotyping.

Effects of Selenium on Fusarium Growth and Associated Fermentation Products and the Relationship with Chondrocyte Viability

This study determined the effects of selenium on the growth of Fusorium strains and the effects of products extracted from the fungal cultures on relevant indicators of chondrocytes injury.

Glycosylation-independent binding to extracellular domains 11-13 of mannose-6-phosphate/insulin-like growth factor-2 receptor mediates the effects of soluble CREG on the phenotypic proliferation of vascular smooth muscle cells

Background The present study aimed to investigate the detailed mode and specific sites for their binding as well as the functional relevance of this binding in the phenotypic proliferation of vascular smooth muscle cells(SMCs). Methods CREG knocked-down SMCs were employed to evaluate the biological activity of wtCREG and mCREG.Expressions of SMC differentiation markers SM myosin heavy chain(SM-MHC),SM-actin,heavy caldesmon and myocardin were determined by Western blotting using specific antibodies. Cellular growth of SMCs was assessed by bromide dewuridine (BrdU) incorporation and cell cycle analysis on fluorescence-activated cell sorting(FACS).A solid-phase binding assay was used to study the binding of CREG to extracellular domains of M6P/IGF2R.The cellular co-localization of the two recombinant CREGs with M6P/IGF2R was detected on SMC surface by immunoprecipitation and immunofluorescence analysis.Results The molecular weight of wtCREG was around 30 kD while that of the mCREG was～25 kD.Treatment of wtCREG with PNGase F reduced its molecular weight from～30 kD to～25 kD,whereas PNGase F treatment had no effect on the molecular weight of mCREG.Both wtCREG and mCREG proteins enhanced SMC differentiation,inhibited BrdU incorporation,and arrested cell cycle progression when added to the culture medium.In CREG knocked-down SMCs,the amount of CREG detected by immunoblotting in M6P/IGF2R immunoprecipitates was significantly reduced when compared to normal cells.Both recombinant CREGs co-immunoprecipitated with M6P/IGF2R, although slightly reduced amount of the mutant CREG was detected in M6P/IGF2R immunoprecipitates.Immunostaining revealed that His-tagged CREGs co-localized with IGF2R on the cell surface in a glycosylation-independent manner.In vitro binding assay showed that CREGs bound to M6P/ IGF2R extracellular domains 7-10 and 11-13 in a glycosylation -dependent and -independent manner,respectively.Further blocking experiments using soluble M6P/IGF2R fragments and M6P/IGF2R neutralizing antibody indicated that the biological activities of recombinant CREGs in SMC growth and the up-regulation of SMC differentiation markers were all abolished by treatment with the M6P/IGF2R neutralizing antibody. However,although the growth inhibitory effect of wtCREG was nearly abolished by D7-10 or D11-13,the effect of mCREG was only reversed by Dll-13,indicating that the binding to domains 11-13 is required for CREG to modulate the proliferation of SMCs.Conclusions These data suggest that solubleCREG proteins can exert their biological function via binding to the extracellular domains 7-10 and 11-13 of cell surface M6P/IGF2R in both a glycosylation-dependent and -independent manner.

Characteristics of In_(0.52)Al_(0.48)As Grown on InP(100) Substrates by Molecular Beam Epitaxy: Growth Optimisation and Effects of Si Doping

Growth of In0.52Al0.48As epilayers on InP (100) substrates by molecular beam epitaxy at a wide range of substrate tempreatures (470~550℃) and at different Si doping levels has been carried out. Low temperature photoluminescence (PL) and double-axis X-ray diffraction (XRD) analyses shaw a strong dependence of the PL and XRD linewidths, XRD intensity ratio (Lepi/Isub), and lattice-mismatch on the substrate temperature. The X-ray diffraction peaks of samples grown at law temperatures show a composition of smaller peaks, indicating the presence of disorder due to alloy clustering. Raman scattering measurements of the same samples show an additional higher energy mode at 273 cm-1 in addition to the InAs-like and AlAs-like longitudinal-optic (LO) phonon modes. Samples doped with Si show an inverted S-shaped dependence of the PL peak energy variation with the temperature which weakens at high doping levels due to a possible reduction in the donor binding energy. Supported be observations of a reduction in both the AlAs-like and InAs-like LO phonon frequencies and a broadening of the LO phonon line shape as the doping level is increased, the PL intensity also shows in increasing degrees at higher doping levels, a temperature dependence which is characteristic of disordered and amorphous materials.

Growth inhibitory response and ultrastructural modification of oral-associated candidal reference strains (ATCC) by Piper betle L. extract

Candida species have been associated with the emergence of strains resistant to selected antifungal agents. Plant products have been used traditionally as alternative medicine to ease mucosal fungal infections. This study aimed to investigate the effects of Piper betle extract on the growth profile and the ultrastructure of commonly isolated oral candidal cells. The major component of Po betle was identified using liquid chromatography-mass spectrophotometry （LC-MS/MS）. Seven ATCC control strains of Candida species were cultured in yeast peptone dextrose broth under four different growth environments： （i） in the absence of P. betle extract; and in the presence of P. beUeextract at respective concentrations of （ii） 1 mg.mL-1; （iii） 3 mg.mL-1; and （iv） 6 mg.mL- 1 The growth inhibitory responses of the candidal cells were determined based on changes in the specific growth rates （μ）. Scanning electron microscopy （SEM） was used to observe any ultrastructural alterations in the candida colonies. LC-MS/MS was performed to validate the presence of bioactive compounds in the extract. Following treatment, it was observed that the p-values of the treated cells were significantly different than those of the untreated cells （P〈0.05）, indicating the fungistatic properties of the P. beUe extract. The candidal population was also reduced from an average of 13.44× 10^6 to 1.78×10^6 viable cell counts （CFU）.mL-1, SEM examination exhibited physical damage and considerable morphological alterations of the treated cells. The compound profile from LC-MS/MS indicated the presence of hydroxybenzoic acid, chavibetol and hydroxychavicol in P. betle extract. The effects of P. betle on candida cells could potentiate its antifungal activity.

Credit Risk Model Taking Account of Inflation and Its Contribution to Macroeconomic Discussion on Effect of Inflation on Output Growth

We use Extended Merton model(EMM)for estimating the firm’s credit risks in the presence of inflation.We show quantitatively that inflation is an influential factor making either a benign or adverse effect on the firm’s survival,supporting at the microeconomic level New Keynesian findings of the nonlinear inflation effect on output growth.Lower inflation increasing the firm’s expected rate of return can raise its mean year returns and decrease its default probability.Higher inflation,decreasing the expected rate return,makes the opposite effect.The magnitude of the adverse effect depends on the firm strength:for a steady firm,this effect is small,whereas for a weaker firm,it can be fatal.EMM is the only model taking account of inflation.It can be useful for banks or insurance companies estimating credit risks of commercial borrowers over the debt maturity,and for the firm’s management planning long-term business operations.

Effect of Cu and Ni on Growth, Mineral Uptake,Photosynthesis and Enzyme Activities of Chlorella vulgaris at Different pH Values

A pH dependent reduction in growth, Pigment, ATP content, O,' evolution, carbonfixation, Photosynthetic electron transport system, nutrient uptake (NO,' and NH4+),nitrate reductase, and ATPase activities and increase in K+ emux of Chlorella vulgaris wasnoticed following supplementation of Cu and Ni to the culture medium. PS II was foundto be more sensitive to both pH and metals than PS I. Though, nitrate reductase (NR) wasmore sensitive to both PH and metals, the ATPase was however, more sensitive t0 metalsbut less sensitive to acidic pH. Acid PH was found to dst the nutrient (NO,' and NH4+)uptake and nitrate reductase in a non-competitive manner. The inhibition Pnduced by thetest metals alone was of noncompetitive type for NO3' uptake, nitrate reductase andATPase and competitive for NH'+ uptake. Acidity not only inhibited the metabolicvariables directly but also through facilitated uptake of metals and increased membranepermeability. A very low sensitivity of ATPase to acidic pH seems to be resgnsible forthe survival of algae in acid environment.

Growth mechanism and modification of electronic and magnetic properties of silicene

Silicene, a monolayer of silicon atoms arranged in a honeycomb lattice, has been undergoing rapid development in recent years due to its superior electronic properties and its compatibility with mature silicon-based semiconductor technology. The successful synthesis of silicene on several substrates provides a solid foundation for the use of silicene in future microelectronic devices. In this review, we discuss the growth mechanism of silicene on an Ag(111) surface, which is crucial for achieving high quality silicene. Several critical issues related to the electronic properties of silicene are also summarized, including the point defect effect, substrate effect, intercalation of alkali metal, and alloying with transition metals.

Effect of Pesticides on Growth of Rhizobia and Their Host Plants During Symbiosis

Effect of various pesticides (insecticides, fungicides and herbicides) has been studied on growth and efficiency of symbiotic properties of 3 fast growing Rhizobium sp. under green house conditions. The results revealed adverse effects on plant growth and nitrogen fixing capacity as measured by dry weight and total nitrogen content of plants infected with pesticide treated Rhizobium. Of the pesticides tested, herbicides were found to be more effective on the above parameters than the insecticides and fungicides.

Effect of calcitonin gene-related peptide and nerve growth factor on spatial learning and memory abilities of rats following focal cerebral ischemia/reperfusion

BACKGROUND: Calcitonin gene-related peptide (CGRP) and nerve growth actor (NGF) cam improve spatial learning and memory abilities of rats with cerebral ischemia/reperfusion; however, the effect of combination of them on relieving learning and memory injury following cerebral ischemia/reperfusion should be further studied. OBJECTIVE: To study the effects of exogenous CGRP and NGF on learning and memory abilities of rats with focal cerebral ischemia/reperfusion. DESIGN: Randomized controlled animal study. SETTING: Department of Neurosurgery, the Second Hospital of Xiamen; Department of Neurosurgery, the Second Affiliated Hospital of China Medical University; Department of Neurobiology, Basic Medical College of China Medical University. MATERIALS: A total of 30 healthy male SD rats, aged 8 weeks, of clean grade, weighing 250-300 g, were provided by Experimental Animal Department of China Medical University. All rats were randomly divided into sham-operation group, ischemia/reperfusion group and treatment group with 10 in each group. The main reagents were detailed as the follows: 100 g/L chloral hydrate, 0.5 mL CGRP (2 mg/L, Sigma Company, USA), and NGF (1× 106 U/L, 0.5 mL, Siweite Company, Dalian). METHODS: The experiment was carried out in the Department of Neurobiology, Basic Medical College of China Medical University from February to July 2005. Rat models of middle cerebral artery occlusion were established by method of occlusion, 2 hours after that rats were anesthetized and the thread was slightly drawn out for 10 mm under direct staring to perform reperfusion. Rats in the ischemia/reperfusion group received intraperitoneal injection of 1 mL saline via the abdomen at two hours later, while rats in the treatment group at 2 hours later received intraperitoneal injection of 2 mg/L CGRP (0.5 mL) and 1×106 U/L NGF (0.5 mL) once a day for 10 successive days. First administration was accomplished within 15 minutes after ischemia/reperfusion. Rats in the sham-operation group were separated of the vessels without occlusion or administration. The neural function was evaluated with Zea Longa 5-grade scale. Animals with the score of one, two and three points received Morris water-maze test to measure searching time on platform (omitting platform-escaping latency). Meanwhile, leaning and memory abilities of animals were reflected through testing times of passing through platform per minute. MAIN OUTCOME MEASURES: Experimental results of omitting platform-escaping latency and spatial probe. RESULTS: Three and two rats in the ischemia/reperfusion group and treatment group respectively were not in accordance with the criteria in the process, and the rest were involved in the final analysis. ① Comparisons of platform-escaping latency during Morris water-maze test in all the three groups: Ten days after modeling, the platform-escaping latency in the ischemia/reperfusion group was obviously longer than that in sham-operation group (P < 0.01), and was significantly shorter than that in the treatment group (P < 0.01). ② Comparisons of times of passing through platform in all the three groups: Times of passing through platform were remarkably less in the ischemia/reperfusion group than those in the sham-operation group [(1.79±0.39), (4.30±0.73) times/minute, P < 0.01], and those were markedly more in the treatment group than the ischemia/reperfusion group [(3.16±1.03), (1.79±0.39) times/minute, P < 0.01]. CONCLUSION: CGRP and NGF are capable of ameliorating the abilities of spatial learning and memory in MCAO rats, which indicates that CGRP and NGF can protect ischemic neurons.

The effect of insulin-like growth factor 1 on the fusion of cranial suture

Objective To evaluate the effect of insulin-like growth factor 1 for the bone induction and the regulation for the fusion of the sagittal cranial sutures. Methods The cells, derived from cranial sutures in the newborn SD rats and the sagittal suture from the mice, were cultured with a serum-free medium and treated with and without insulin-like growth factor 1. The osteoblast phetotypes (osteocalcin, alkaline, osteoponcin and type-1 collagen) were measured with the RT -PCR and ELISA, and the explanted sagittal sutures were then evaluated under light microscopy. Results The cells, treated with the insulin-like growth factor 1, significantly produced more osteocalcin, alkaline, osteoponcin and type-1 collagen than those without insulin-like growth factor 1. The fusion of the sagittal suture explants will delay till to 30 days when it was not treated with IGF1. However, in the group with IGF1 the fusion was observed to start in 8 days, and a small amount of the sagittal suture fusion was found at the 20th

The effect of endogenous transforming growth factor β_1 on the growth of bladder cancer cells in vitro

Objective To investigate the influence of endogenous transforming growth factor β1(TGFβ1) on the cell cycle regulation and proliferation of bladder cancer. Methods A constructed replication defective retroviral vector pRevTβ-AS, which carried antisense RNA of TGFβ1.was transfected to a bladder cancer cell line EJ. The proliferation and clone-formation of transferred cells were observed in vitro,and the alteration of cell cycle was also detected by flow cytometric analysis. Results TGFβ1 antisense RNA was transferred into EJ cell and expressed efficiently. After the inhibition of target gene expression in EJ cells, the reduced growth and clone-formation rates were demonstrated, and the proliferative indexes were decreased by 12 % . The ratios of GO and G1 stage cells to June 2003 Vol12 No2 the antisense RNA-transfected EJ cells were increased, simultaneously,the ratio of S stage cells to the antisense RNA-transfected EJ cells ratios were decreased, compared with the control group. Conclusion The

Effect of Ligustrazine on Expressions of Basic Fibroblast Growth Factor and Its Receptor in Bone Marrow of Mice with Acute Radiation Injury

Objective: To study the expressions of basic fibroblast growth factor (bFGF) and its receptor (bFGFR) in bone marrow of mice with acute radiation injury, and to evaluate the effect of Ligustrazine (Lt) on them. Methods: Fifty-six Kunming mice of clean grade were randomly divided into 3 groups, the normal group, the control group and the Lt group. Mice in the latter two groups were once homogeneously systemic irradiated with 6.0 Gy of 60 Co, with the absorption dose rate of 0. 56 Gy/min, then treated with saline (0.2 ml/ mice) or Lt (2 mg/mice) respectively, twice a day through gastrogavage for successive 13 days. Mice were sacrificed in batch on the 3rd, 7th and 14th day by cervical dislocation to collect the bilateral femoral bone marrow for preparing bone marrow mono-nuclear cell (BMMNC) suspension. The bFGFR expression on surface of BMMNC was determined by flow cytometry; and the bFGF expres-sion level in one side of femoral bone marrow tissue was detected by immunohistochemistry with SABC-AP assay. Results: The bFGF expression in bone marrow of mice on the 3rd, 7th and 14th day after acute radiation injury all were significantly lower than that of the normal mice (P<0.05 or P<0.01). The expressions of bFGF and bFGFR in the Lt group detected were significantly higher than that in the control group detected at the corresponding time points (P<0.05 or P < 0.01). Conclusion:By way of enhancing bFGF expression in bone marrow and bFGFR expression on surface of BMMNC to accelerate the repairing of hemopoietic micro-environment in bone marrow might be one of the mechanisms of Lt in promoting hemopoietic function reconstitution after acute radiation injury.Original article on CJITWM (Chin) 2004;24(5):439

The effect of interleukin 6 on the growth of LNCaP and PC-3 prostatic carcinoma cells

Objective To investigate the effect of IL-6 on prostatic carcinoma cell lines, and differential effects on androgen-dependent and androgen-independent prostatic carcinoma cells. Methods The IL-6 producing capacities of LNCaP and PC-3 cells were determined, and effects of exogenous IL-6 and anti-IL - 6 antibodies on LNCaP and PC - 3 cells were examined. Results LNCaP produced a very small amount of IL-6, but PC-3 produced more, the concentraion of IL-6 being 190 pg/48 h per ml(1 × 106). The exogenous IL-6 inhibited LNCaP growth significantly,but had no obvious effect on PC -3 cells. Anti-IL-6 antibodies lowered PC-3 cells growth rate but had neutral effect on LNCaP. Conclusion PC-3 cells produces IL-6 massively in autocrine manner. IL-6 could be antagonized by anti-IL-6 antibodies,resulting in slowing PC-3 cells growth, and LNCaP cells growth could be inhibited by exogenous IL-6.7 refs,2 tabs.

Effect of plant growth regulator on rate of twin seedlings of rice with polyembryony

Rice with polyembryony characterized bytwin seedlings is a good genetic tool for apomixisresearch.A study on the effect of five plantgrowth regulators(IAA,KT,GA,2,4-D and6-BAP)on rate of twin seedlings in 3 rice varie.ties with polyembryony(Shuang 3,Shuang 13and Lu 52)was conducted.The results showed

Research Progress on the Growth-Promoting Effect of Plant Biostimulants on Crops

A Plant Biostimulant is any substance or microorganism applied to plants to enhance nutrition efficiency,abioticstress tolerance,and/or crop quality traits,regardless of its nutrient content.The application of Plant biostimulants(PBs)in production can reduce the application of traditional pesticides and chemical fertilizers and improvethe quality and yield of crops,which is conducive to the sustainable development of agriculture.An in-depthunderstanding of the mechanism and effect of various PBs is very important for how to apply PBs reasonablyand effectively in the practice of crop production.This paper summarizes the main classification of PBs;Thegrowth promotion mechanism of PBs was analyzed from four aspects:improving soil physical and chemical properties,enhancing crop nutrient absorption capacity,photosynthesis capacity,and abiotic stress tolerance;At thesame time,the effects of PBs application on seed germination,seedling vigor,crop yield,and quality were summarized;Finally,how to continue to explore and study the use and mechanism of PBs in the future is analyzedand prospected,to better guide the application of PBs in crop production in the future.