Sensitivity of Commercial Enzyme Inhibition Colorimetric Pesticide Residue Rapid Test Kit to a Variety of Pesticides

[Objectives]To fully understand the quality of commercial enzyme inhibition-colorimetric pesticide residue rapid detection kits,so that they can play a greater role in the detection and supervision of agricultural products.[Methods]The sensitivity of 28 kinds of pesticides was determined by using the commercially available enzyme inhibition colorimetric rapid detection kit with Hendu brand.[Results]There was a significant difference in the sensitivity of the kit to each pesticide,and the kit was more sensitive to dichlorvos among the 28 pesticides tested.The sensitivity to methyl isosalifos,dimethoate,isocarbophos,fenthion and phorate was poor,and the sensitivity to quinalphos was different between 3.0 and 2.5 mL.[Conclusions]The large difference of the sensitivity of the enzyme inhibition-colorimetric rapid detection kit for pesticide residues to different kits is a reason for the false positive and false negative test results of the kit,which needs to be considered by relevant personnel.

Genome-wide association study of seedling nitrogen-use efficiency-associated traits in common wheat(Triticum aestivum L.)

Nitrogen(N)fertilizer application is essential for crop-plant growth and development.Identifying genetic loci associated with N-use efficiency(NUE)could increase wheat yields and reduce environmental pollution caused by overfertilization.We subjected a panel of 389 wheat accessions to N and chlorate(a nitrate analog)treatments to identify quantitative trait loci(QTL)controlling NUE-associated traits at the wheat seedling stage.Genotyping the panel with a 660K single-nucleotide polymorphism(SNP)array,we identified 397 SNPs associated with N-sensitivity index and chlorate inhibition rate.These SNPs were merged into 49 QTL,of which eight were multi-environment stable QTL and 27 were located near previously reported QTL.A set of 135 candidate genes near the 49 QTL included TaBOX(F-box family protein)and TaERF(ethylene-responsive transcription factor).A Tabox mutant was more sensitive to low-N stress than the wild-type plant.We developed two functional markers for Hap 1,the favorable allele of TaBOX.

Inhibition Effect of Antagonistic Fungal Strain BOS-013 against the Pathogen of Rice Blast (Pyricularia oryzae)

[ ObjeeUve ] To search for the beneficial microorganisms and their metabolic products with control effect against rice Mast, the paper studied the inhibi- tion effect of the fermentation broth of actinomycetes BOS-013 strain against the pathogen of rice blast （Pyricularia oryzae）. [ Method ] With P. oryzae as the target indicator fungus, the inhibition effect of the fermentation broth of BOS-013 strain and its extracts from different solvents against the pathogen were determined using cylinder plate method and filter paper method. [ Result] The results showed that the inhibition rate of the fermentation broth of BOS-013 strain with fungus amount of 4×10^8 cfu/ml against P. oryzae was 92.0% ±0.5% ; the fermentation broth still had inhibition effect against P. oryaae after inactivation under high temperature and high pressure, and the inhibition rate was 60.0%±0.5%. After absorbed by non-polar CAD-45 type macroperous adsorption resin and eluted by 60% etha- nol, the antifungal activity of the fermentation broth was still high, and the diameter of inhibition zone reached 33.0 mm. [ Conclusion] The fermentation broth of BOS-O13 strain had significant inhibition effect against P. oryzae. The results would provide foundation for further clarification of inhibition mechanism of BOS-013 strain fermentation broth against P. oryzae and its practical application.

Enzyme Inhibition Rate Method for Rapid Detection of Organophosphorus and Carbamate Pesticides in Cowpea

[Objectives ] The paper was to explore enzyme inhibition rate method for rapid detection of organophosphorus and carbamate pesticides in cowpea. [ Methods ] Acetylcholinesterase （ACHE） was added to cowpea extract, to determine the inhibition rate of extract against enzyme. The influences of different sampiing methods and sampling parts on detection results were compared. [ Results] The positive rate of standard sampling was 18.18% higher than that of non-stand- ard sampling, and the positive rate of samples collected from cowpea tail was 16.67% higher than that collected from other parts. [ Condmions] Enzyme inhibi- tion rate method is suitable for rapid detection of organophosphorus and carbamate pesticides in cowpea.

Study on the Guidance of Platelet Inhibition Rate Detected with Thrombelastogram in Antiplatelet Therapy for Acute Non-Cardiogenic Stroke

Objective:To investigate the application value of thrombelastogram(TEG)in the detection of platelet inhibition rate for antiplatelet therapy for acute non-cardiogenic stroke.Methods:A total of 100 patients with ischemic non-cardiogenic stroke were selected for this study from September 2020 to October 2021.Patients were randomly divided into experimental group and control group,with 50 cases for each group.Before and after 1 week of antiplatelet drug treatment,the platelet inhibition rate in the experimental group was measured with arachidonic acid(AA)and adenosine diphosphate(ADP)by TEG;no platelet inhibition rates detection was conducted for the control group.The dose and type of drugs were adjusted for the experimental group according to the platelet functions and medication based on the clinical experience conducted for the control group.The neurological deficits of the discharged patients were scored with NIHSS score,mRS score,stroke recurrence,hemorrhage,and other events were followed up at the 3rd month of discharge.Results:In the experimental group,the inhibition rates of AA and ADP were significantly higher than those before treatment(both P<0.05).After treatment,the inhibition rates of AA and ADP in dual antiplatelet patients were higher than those of monoclonal antiplatelets(both P<0.05).The NIHSS score at discharge and the mRS score at the 3rd-month-follow-up in the experimental group were lower than those in the control group(both P<0.05).The incidences of stroke recurrence and hemorrhage events in the experimental group were lower than those in the control group(P<0.05).Conclusion:The application of a thrombelastogram in the detection of platelet inhibition rate to guide antiplatelet therapy in patients with acute non-cardiogenic stroke reduces the recurrences of cerebral infarction and the risk of hemorrhage and improves patients’clinical prognosis.

Effects of Sea Brine on Growth of Fusarium graminearum

[ Objective ] The paper was to study the effect of sea brine on the growth of Fusarium graminearum. [ Method] The inhibition rate of sea brine against F. gram/nearum was measured using mycelial growth rate method. The inhibition effect of sea brine against infection of F. gram/nearum on maize was measured through leaf culture method in vitro. [Result] With the decrease of sea brine concentration, its inhibition against F. gram/nearum had no remarkable regulation, which first decreased, then increased, and finally decreased. It had the best inhibition effect as the concentration was 0.005 0% with the inhibition rate of 31.2%. 0.050 0% sea brine had the best inhibition effect against the infection of F. graminearum with the inhibition rate of 44.3%. [ Conclusion] The results provided theoretical basis for the application of sea brine in the aspects of plant diseases and vests control

Activity Determination of 8 Chinese Herbs against Hepatoma Cell SMMC-7721 in Vitro by MTT Method

[Objective] The aim was to build up a set of efficient and rapid models for laboratory to screen anti-hepatocellular carcinoma active substance in vitro. [ Method] By using MTT method, the activities of anti-hepatocellular carcinoma SMMC-7721 in vitro from Cymbopogon distans, Lobelia chinensis, Buddleja offlcinalis, Glycyrrhiza uralensis, Sanguisorba officinalis, Bupleurum chinense, Apium graveolen and Curuma zedoaria were tested. The growth curve of hepatoma cell was described, and the growth status in different periods were observed by inverted microscope. [ Result] Cells induced by active substance would be condensing, clear brim, which have significant differences from normal SMMC- 7721 cells. The results suggested that ESCG, ESCC, ESCB could inhibit proliferation of SMMC-7721 cells at the concentration of 1.0 -1.5 mg/ml, and the inhibition rate were 51.6%, 48.5%, 52.9% respectively. With the increasing of concentration, the inhibition strengthened. [ Conclusion] MTT method could be used as a basic model for screening important anti-hepatoma.

Astragalus polysaccharides can regulate cytokine and P-glycoprotein expression in H22 tumor-bearing mice

AIM:To investigate the adjunct anticancer effect of Astragalus polysaccharides in H22 tumor-bearing mice.METHODS:To establish a solid tumor model,5.0 × 10 6 /mL H22 hepatoma cells were inoculated subcutaneously into the right armpit region of Kunming mice(6-12 wk old,18-22 g).When the tumors reached a size of 100 mm 3,the animals were treated as indicated,and the mice were randomly assigned to seven groups(n = 10 each).After ten days of treatment,blood samples were collected from mouse eyes,and serum was harvested by centrifugation.Mice were sacrificed,and the whole body,tumor,spleen and thymus were weighed immediately.The rate of tumor inhibition and organ indexes were calculated.The expression levels of serum cytokines,P-glycoprotein(P-GP) and multidrug resistance(MDR) 1 mRNA in tumor tissues were detected using enzyme-linked immunosorbent assay,Western blotting,and quantitative myeloid-derived suppressor cells reverse transcription-polymerase chain reaction,respectively.RESULTS:The tumor inhibition rates in the treatment groups of Adriamycin(ADM) + Astragalus polysaccharides(APS)(50 mg/kg),ADM + APS(100 mg/kg),and ADM + APS(200 mg/kg) were significantly higher than in the ADM group(72.88% vs 60.36%,P = 0.013;73.40% vs 60.36%,P = 0.010;77.57% vs 60.36%,P = 0.001).The spleen indexes of the above groups were also significantly higher than in the ADM group(0.65 ± 0.22 vs 0.39 ± 0.17,P = 0.023;0.62 ± 0.34 vs 0.39 ± 0.17,P = 0.022;0.67 ± 0.20 vs 0.39 ± 0.17,P = 0.012),and the thymus indexes of the ADM + APS(100 mg/kg) and ADM + APS(200 mg/kg) groups were significantly higher than in the ADM group(0.20 ± 0.06 vs 0.13 ± 0.04,P = 0.029;0.47 ± 0.12 vs 0.13 ± 0.04,P = 0.000).APS was found to exert a synergistic antitumor effect with ADM and to alleviate the decrease in the sizes of the spleen and thymus induced by AMD.The expression of interleukin-1α(IL-1α),IL-2,IL-6,and tumor necrosis factor-α(TNF-α) was significantly higher in the ADM + APS(50 mg/kg),ADM + APS(100 mg/kg) and ADM + APS(200 mg/kg) groups than in the ADM group;and IL-10 was significantly lower in the above groups than in the ADM group.APS could increase IL-1α,IL-2,IL-6,and TNF-α expression and decrease IL-10 levels.Compared with the ADM group,APS treatment at a dose of 50-200 mg/kg could downregulate MDR1 mRNA expression in a dose-dependent manner(0.48 ± 0.13 vs 4.26 ± 1.51,P = 0.000;0.36 ± 0.03 vs 4.26 ± 1.51,P = 0.000;0.21 ± 0.04 vs 4.26 ± 1.51,P = 0.000).The expression level of P-GP was significantly lower in the ADM + APS(200 mg/kg) group than in the ADM group(137.35 ± 9.20 mg/kg vs 282.19 ± 20.54 mg/kg,P = 0.023).CONCLUSION:APS exerts a synergistic anti-tumor effect with ADM in H22 tumor-bearing mice.This may be related to its ability to enhance the expression of IL1α,IL-2,IL-6,and TNF-α,decrease IL-10,and downregulate MDR1 mRNA and P-GP expression levels.

A comparative study of classical and biochemical endpoints for phytotoxicity testing of chlorobenzoic acids

The phytotoxicity of chlorobenzoic acids(CBAs) was studied and the biochemical endpoints' suitability and sensibility was evaluated. Two terrestrial plant species in the same family were exposed to different concentrations of CBAS and tested their germination according to the guideline of Organization for Economic Cooperation and Development(OECP, 1984). The results showed that CBA dose-inhibition rate of classical endpoint had the distinct linear relationship in the range of 10%—50% inhibition rate for root elongation(p<0.01), and the dose variances of CBAs had the greater influence on the inhibition rate of germination than on inhibition rate of root elongation. The CBA dose half effect concentration-inhibition rate of two antioxidant enzyme activity superoxide dismutase(SOD) and catalase (CAT) had the quadratic relationship, and CBA dose-inhibition rate of the peroxides(POD) activity had the linear relationship(p<0.05). Comparing the half effect concentration (EC_ 50) of two kinds of endpoints, the POD activity was more sensitive than classical endpoint, however, SOD and CAT activity were not sensitive in the experiment.

Inhibitory Effect of Buddlejasaponin Ⅳ on Hepatocarcinoma 22(H_(22)) in Mice

[Objective] This study aimed to investigate the inhibitory effect of buddle- jasaponin IV on growth of hepatocarcinoma 22 （H22） tumor in mice. [Method] The H= tumor cells were transplanted in the right axillary skins of mice. The tumor- bearing mice were randomly divided into five groups, including control group, CTX group （20.0 mg/kg） and buddlejasaponin IV treatment groups （0.25, 0.50 and 1.00 mg/kg）. There were 10 mice in each group. During the treatment, the body weights and survivals of mice in all groups were recorded. The buddlejasaponin IV was in- jected into the abdominal cavities of mice, which lasted for 10 consecutive days. All the mice were slaughtered the next day. The tumors in the abdominal cavities were tanked out and weighed. The tumor inhibition rate, spleen index and thymus index, as well as SOD activity, MDA content, GGT activity and AKP activity in serum were determined. [Result] Compared with the control group, the high- and middle- dosage buddlejasaponin IV treatment groups all showed significant （P〈0.01） inhibito- ry effects on transplanted H22 tumor in mice with tumor inhibition rates of 56.96% and 50.63%, respectively. Compared with those in the control group, the SOD ac- tivity of mice in the high-dosage buddlejasaponin IV treatment group was significant- ly increased （P〈0.05）, and the MDA contents, GGT and AKP activities in mice in the high-, middle- and low-dosage buddlejasaponin IV treatment groups were all sig- nificantly reduced （P〈0.01）. There were no significant differences in all the indexes, except SOD activity, between the CTX and control groups. [Conclusion] Buddlejas- aponin IV has certain inhibitory effect on H22 tumor, of which the mechanism might be related to antioxidation capacity in body.

Studies on photoprotective mechanism of desert plant Reaumuria soongorica under progressive soil drying

Reaumuria soongorica （pall.） Maxim, a perennial desert semi-shrub, is widely found in semi-arid areas of China. It shows strong tolerance to drought, high temperature and intense radiation in its natural habitat. In the present study, photoprotective mechanism of R. soongorica was investigated by analyzing diurnal variations of gas exchange and chlorophyll fluorecence parameters during progressive soil drying. The results show that leaf water potential of R. soongorica decreased when the soil water content dropped. Diurnal patterns of net photosynthetic rate （Pn） changed from ＂two peaks＂ to ＂one peak＂ under drought stress, and the leaf water use efficiency （WUE） increased under moderate drought and declined under severe drought. Pn , the primary maximum photochemical efficiency of PSII （Fv/Fm） and the quantum efficiency of non-cyclic electron transport of PSII （ΦPSII） decreased obviously at noon, and showed a photoinhibition phenomenon. But, the non-photochemical quenching of fluorescence （NPQ） soon reached its maximum in the day and then remained almost at the high level until 17：00, indicating that the xanthophylls cycle-dependent thermal energy dissipation played an important role. Diurnal variations of the original chlorophyll fluorescence （Fo） increased at first and then decreased. The increased value of F o under drought stress indicates that there was a reversible inactivation of PSII reaction center. These results indicate that the photoprotective mechanism in R. soongorica was the photoinhibition by using both the xanthophylls cycle-dependent thermal energy dissipation and the reversible inactivation of PSII reaction center under drought stress.

An Eco-Friendly High-Effective Scale Inhibitor for High Salt Brine

Now the mining of high salt underground brine has been an important aspect of salt lake mining,which is the necessary support to the development of national economy.With the change of underground geological

ANTI-CANCER EFFECT OF PSP PURIFIED PRODUCTS ON HUMAN TUMOR CELL LINES IN VITRO

The anti-cancer effect of PSP purified products, PSP-A, PSP-B, PSP-C and crude product PSP-Cr was compared on four human tumor cell lines in vitro. It was found that the inhibition rate of cell proliferation of PSP-A was higher than that of PSP-Cr (P<0. 05). On SPC cells, the inhibition rate of PSP-A at a dosage of 1000μg/ml was 62. 7%, being the highest as compared with those on the other three cell lines. Morphological changes were seen in all the four cell lines, especially in SPC cells after PSP-A treatment.

Effect of grape proanthocyanidins on tumor growth and angiogenesis in H22 liver cancer xenograft model

Objective: The aim of this study was to investigate the effect of grape proanthocyanidins(GPC) on the growth and angiogenesis of hepatocellular carcinoma H22 cells xenograft in mice. Methods: The xenograft model was established using injected subcutaneously H22 cells into the right axilla of the mice. Each group was treated with different doses of GPC and Endostar. All these treatments were maintained for 10 days, and mice were sacrificed. The xenograft tumors in mice were measured. The proliferation activity level of H22 cells was determined by MTT assay, and the levels of vascular endothelial growth factor(VEGF) protein were examined by immunohistochemistry. Results: When treated with 50, 100 and 200 mg/kg of GPC and Endostar, the tumor inhibition rates were 13.17%, 23.37%, 36.15% and 14.71%, respectively. The tumor weight of xenograft was significantly lighter in high GPC group than the control group(P < 0.05). The ODs in GPC groups were 0.835, 0.666 and 0.519, respectively. The absorbances in middle and high GPC groups were statistically significant, compared with control group(P < 0.01). Immunohistochemical technique showed the expression of VEGF of the GPC groups was downregulated significantly compared with the control group(P < 0.01). Conclusion: GPC can inhibit the growth of hepatocellular carcinoma H22 cell xenograft in mice. The inhibition of angiogenesis by the down-regulation of VEGF expression may play a key role in the anti-neoplastic effect of GPC.

Study on Antifungal Activity of Some Medicinal Plants against Gray Mold(Botrytis cinerea)

In order to investigate antifungnl effect of medicinal plant extracts on Botrytis cinerea, the antifungal activity of ethanol extracts of 8 medicinal plants in- eluding Ginkgo biloba against Botrytis cinerea was determined by growth rate method. The results showed that Ginkgo biloba and Ginnamomum cassia extracts had significant inhibition effects on B. cinema mycelium growth （P 〈 0.05）, with inhibition rates over 70% and ECho values of 0.027 mg/ml and 0.039 mg/ml, re- spectively, significantly different from the antifungal effects of other kinds of medicinal plants ; and P. ternata and A. tsaoko extracts showed the second highest in- hibition effects, with ECho values of 0. 011 9 and 0. 039 3 mg/ml, respectively. Further experimental application could be carried out.

MTT Detection of the Toxicity on CdTe Quantum Dots

Objective: The quantum dots are the useful materials in microelectronics and biomedical research. However its toxicity has to be considered. We studied the effect of cell inhibition with ZnS core quantum dots and CdTe quantum dots modified with Thioglycolic acid or Cysteine functional group (TGA-CdTe, TGA-CdTe/ZnS, Cys-CdTe, Cys-CdTe/ZnS) on Caco-2 cell proliferation. Methods: We studied the effect of cell inhibition with ZnS core QDs and CdTe QDs modified with functional group on Caco-2 cell proliferation by MTT assay at 0, 12.5, 25, 50, 100 μg/ml and 6, 24, 48 h. Result: Our results showed that all QDs have inhibited cell proliferation and reached maximum 79.21%. The inhibition rate of Cys-modified QDs increased with the increase of concentration and reached maximum 66.72%. The inhibition rate of TGA-modified QDs increased with the increase of time. The ratios of Cys-modified to TGA-modified were less than 1 at all concentrations and three exposure times (P ≤ 0.01). The average ratios of Cys-CdTe/ZnS to Cys-CdTe reached 1.11 only for 48 h (P ≤ 0.05). The ratios of TGA-CdTe/ZnS to TGA-CdTe were closed to 1 at all concentrations and exposure times. Conclusion: The regularity of QDs modified with functional group is that inhibition of TGA-modified higher than Cys-modified. Inhibition exhibited dose-dependent for Cys-modified while exhibited time-dependent for TGA-modified. The regularity of CdTe-QDs with ZnS or not is that the inhibition of Cys-CdTe/ZnS was higher than Cys-CdTe while TGA-CdTe/ZnS and TGA-CdTe were consistent.

Effects of Different Doses of Doxorubicin on H9C2 Cells

Objective: To study the effect of different doses of doxorubicin on H9C2 cells and to provide a reference for the clinical study of doxorubicin. Methods: Doxorubicin (1, 2, 4, 6, 10 ug/ml) was co-cultured with H9C2 cells for 6, 12 and 24 hours. The morphological changes of cells were observed, and the cell inhibition rates of different time and drug concentration were calculated. Results: Doxorubicin could inhibit the activity of cardiomyocytes in a dose-dependent manner from 1 to 10 ug/ml. Conclusion: A certain dose of doxorubicin has a toxic effect on cardiomyocytes and can cause cardiomyocyte necrosis and apoptosis.

Visual dyslexia:towards an operational definition from a correlational study

Background:Aim of the study is to provide an operational definition of“visual dyslexia”referred to a particular subgroup of dyslexics characterized by x,y anisotropic perception of the visual space,or unstable ocular dominance,or abnormal binocular interaction,and who benefit from increased interletter spacing.The working hypothesis of this investigation is that in dyslexic children who show the abovementioned alterations the correlation between reading rate and interletter spacing is a marker of visual involvement,and supports a causal role of these visual-perceptive alterations in their reading problems.Methods:Based on the results obtained by three psychophysical tests devised on purpose,a group of 193 school-age disabled readers with normal visual acuity and no significant co-morbidities has been classified into four different classes:non-visual-perceptive sample,anisotropic sample(AS),abnormal binocular interaction sample and unstable dominance sample(UDS).To test for the working hypothesis,the absence of the visual marker has been verified in the non-visual-perceptive sample,and its presence has then been investigated in the remaining classes.Results:The non-visual-perceptive class was negative to the visual marker.In the other classes the average reading rate of words and non-words improved as a function of the distance between characters(AS:R2:0.51 and 0.43,P=0.01 and 0.02 respectively;abnormal binocular interaction sample:R2:0.47 and R2:0.57,P=0.02 and 0.007 respectively;unstable dominance:R2:0.43,P=0.02 at non-words).Yet,individual analysis revealed that the marker was present in no more than 23%of subjects with increased anisotropy,in 50%of unstable dominants,and in only 12%of patients with abnormal interocular inhibition.Conclusions:Even if on a population scale this line of investigation seems able to provide an operational definition of“visual dyslexia”,the individual detection of the“visual dyslexics”requires methodological improvement.

Inhibitive effects of three compositae plants on Microcystis aeruginosa

Based on common phenomena of biochemical interaction between plants and microorganisms,the inhibitive effects of three common terrestrial compositae plants,namely Artemisia lavandulaefolia DC.,Conyza canadensis(L.)Cronq.,and Kalimeris indica(L.)Sch.-Bip.on the blue algae Microcystis aeruginosa was studied.Live compositae plants are co-cultivated with algae in two different inoculation doses for 10 days in 5-pools incubators,in order to exclude the influence of bacteria and nutrients.The results show that Artemisia lavandulaefolia DC has the most inhibitive potential among the three plants as evidenced by the most drastic decrease in optical density(OD680)of the algae.The inhibition rate is 93.3%(with initial inoculation dose of 2.0×10^(6) Cells/mL)and 89.3%(with initial inoculation dose of 4.0×10^(6) Cells/mL)respectively on the 10th day of cultivation.The average inhibition rate during the later half of the experiment is 0.76(with initial inoculation dose of 2.0×10^(6) Cells/mL)and 0.71(with initial inoculation dose of 4.0×10^(6) Cells/mL),respectively.Logistic model analysis shows that compositae plants such as A.lavandulaefolia DC.causes the reduction of the habitat’s carrying capacity of algae.ANOVA analysis is used to determine the similarity and differences between every experimental group and an average inhibitive rate model is used to evaluate the inhibition effects.The results show that A.lavandulaefolia DC.,which grow well in the aquatic environment,may have a great potential in controlling algae bloom in eutrophic water.