Academic cheating interferes with learning among middle school children.

There has been extensive research on the causes of academic cheating, but little is known about its consequences. The current research sought to fill this gap in the literature by examining how cheating by middle school children (total N = 198) affects their learning outcomes. In a naturalistic paradigm, children scored a math test they had taken previously, which gave them an opportunity to cheat by falsely scoring incorrect answers to be correct. Results from this phase showed that 54 % of the children cheated on at least one question. One week later, the children took the same test again, but this time without being given an opportunity to cheat. Among children who cheated, items they had answered incorrectly on the first round showed significantly less improvement on the second round if they had dishonestly scored them as correct rather than honestly scoring them as incorrect. This finding provides the first experimental evidence that academic cheating can interfere with children's learning.

Design, Synthesis, Antimicrobial, and Anticancer Activities of Acridine Thiosemicarbazides Derivatives.

Background: Acridine and thiourea derivatives are important compounds in medicinal chemistry due to their diverse biological properties including anticancer and antimicrobial effects. However, literature reveals some side effects associated with use of acridines. It is suggested that hybrid molecules may reduce the side effects and enhance the beneficial properties due to synergistic activity. The objectives of the present study are to synthesize and evaluate the anticancer and antimicrobial properties of new hybrids of acridine thiosemicarbazides derivatives. Results: The structures of the synthesized compounds 4a-4e were elucidated by MS and NMR spectra. In antimicrobial assay, Compound 4c exhibited potent antimicrobial activity compared to the other four compounds. In anticancer studies, we observed that compounds 4a, 4b, 4d and 4e exhibited high cytotoxicity against the MT-4 cell line, with IC50 values of 18.42 ± 1.18, 15.73 ± 0.90, 10.96 ± 0.62 and 11.63 ± 0.11 µM, respectively. The evaluation of anticancer effects, and the associated mechanism reveals that, the anticancer activities may be related to Topo I inhibitory activity, apoptosis and cell-cycle. Molecular docking studies revealed that the presence of planar naphtho-fused rings and a flexible thiourea group together, could improve DNA-intercalation and inhibition of DNA-Topo I activity. Conclusions: The results of this study demonstrate that the rational design of target derivatives as novel antimicrobial or antitumor leads is feasible.

[Preliminary establishment of integration of Alzheimer's disease and blood stasis syndrome tree shrew model and evaluation of intervention of Panax notoginseng saponins].

To establish the integration of Alzheimer's disease(AD) and blood stasis syndrome tree shrew model. Panax notoginseng saponins (PNS) was used to intervene the model to testify the stability of the model. The level of blood stasis of each group in the tree shrew model was evaluated by analyzing five traditional Chinese medicine(TCM) characterizations, four blood coagulation indexes, plasma nitric oxide (NO) level, plasma superoxide dismutase (SOD) level in each group. Hematoxylin and eosin(HE) staining was used to observe the morphological changes of brain hippocampal neuron cell of each group. Immunohistochemical staining was used to assay the ChAT and SYP levels in brain hippocampus of each group.The blood stasis characterization of the integration of disease and syndrome group was more obvious than the AD group, and that of the drug administration group was lower than that of the integration of disease and syndrome group. Aß1-42, APP, P-Tau, ChAT and SYP level of AD group were lower than those in the blank group, which were further reduced in the model of integration of disease and syndrome. However, the administration of PNS relieved the reduction, indicating that the AD and blood stasis integration syndrome tree shrew model is stable.

[Study on Chemical Composition of Phyllanthus emblica].

OBJECTIVE: To study the chemical constituents of Phyllanthus emblica. METHODS: The chemical constituents were isolated and purified by silica gel, polyamide and Sephadex LH-20 chromatography. Their structures were elucidated by physicochemical proper- ties and spectral analysis. RESULTS: 13 compounds were isolated and identified as Triacontanol (1), Triacontanoic acid (2), ß-Amyrin ke- tone (3), Betulonic acid (4), Daucosterol (5), Lupeol acetate (6), ß-Amyrin-3-palmitate (7), Gallic acid (8), Betulinic acid (9), Ursolic acid (10), Oleanolic acid (11), Quercetin (12) and Rutin (13). CONCLUSION: Compounds 1,2,4,6,7,9,10 and 11 are obtained from Phyllanthus emblica for the first time.

[Protective effect of serum containing n-butanol fraction from Gynostemma pentaphyllum on NG108-15 cell apoptosis induced by Aß25.35 protein].

OBJECTIVE: To investigate the inhibition effect of serum containing n-butanol fractions from Gynostemma pentaphyllum on NG108-15 cell apoptosis induced by Aß25-35 protein in vitro. METHODS: The apoptosis of NG108-15 cells induced by Aß25-35 protein in vitro was evaluated by immunofluorescence and flow cytometry assay. The cellular Caspase-3 level during the apoptosis was determined by ELISA. RESULTS: The serum containing n-butanol fractions from Gynostemma pentaphyllum significantly inhibited the NG108-15 cells apoptosis induced by Aß25-35 protein in vitro,and decreased the cellular Caspase-3 level. CONCLUSION: The inhibition effect of n-butanol fractions from Gynostemma pentaphyllum on NG108-15 cell apoptosis induced by Aß25.35 protein is likely related to its potency on reducing of cellular Caspase-3 level.

Ameliorative Role of Mitochondrial Therapy in Cognitive Function of Vascular Dementia Mice.

BACKGROUND: Mitochondrial dysfunction plays a vital role in the progression of vascular dementia (VaD). We hypothesized that transfer of exogenous mitochondria might be a beneficial strategy for VaD treatment. OBJECTIVE: The study was aimed to investigate the role of mitochondrial therapy in cognitive function of VaD. METHODS: The activity and integrity of isolated mitochondria were detected using MitoTracker and Janus Green B staining assays. After VaD mice were intravenously injected with exogenous mitochondria, Morris water maze and passive avoidance tests were used to detect cognitive function of VaD mice. Haematoxylin and eosin, Nissl, TUNEL, and Golgi staining assays were utilized to measure neuronal and synaptic injury in the hippocampus of VaD mice. Detection kits were performed to detect mitochondrial membrane potential (ΔΨ), SOD activity and the levels of ATP, ROS, and MDA in the brains of VaD mice. RESULTS: The results showed that isolated mitochondria were intact and active. Mitochondrial therapy could ameliorate cognitive performance of VaD mice. Additionally, mitochondrial administration could attenuate hippocampal neuronal and synaptic injury, improve mitochondrial ΔΨ, ATP level and SOD activity, and reduce ROS and MDA levels in the brains of VaD mice. CONCLUSIONS: The study reports profitable effect of mitochondrial therapy against cognitive impairment of VaD, making mitochondrial treatment become a promising therapeutic strategy for VaD.

[Effect of PNS on the activity and content of BACE1 in the brain of SAMP8 mice with Alzheimer's disease].

OBJECTIVE: To explore the effect of Panax notoginseng saponin (PNS) on the activity and content of beta-secretase in the brain of senescence accelerated mouse-prone 8 (SAMP8) mice with Alzheimer's disease. METHODS: Totally 32 SAMP8 mice were randomly divided into the normal control group, the high dose PNS group (200 mg/kg), the low dose group (100 mg/kg), and the huperzine A group (0.3 mg/kg), 8 in each group. Equal volume of double distilled water was given to those in the normal control group. All medication was given by gastrogavage, once daily for two successive months. The activity of BACE1 was assayed by direct immunofluorescent method (DIF). The content of BACE1 protein was detected by Western blot. RESULTS: The relative fluorescence units (RFU/microg) was 2.008 +/- 0.031 in the high dose PNS group, 2.221 +/- 0.029 in the low dose PNS group, and 2.267 +/- 0.076 in the huperzine A group, all lower than that in the normal control group (2.403 +/- 0.058; all P < 0.01). The content of BACE1 protein was 0.900 +/- 0.028 in the high dose PNS group, 1.000 +/- 0.032 in the low dose PNS group, and 0.837 +/- 0.080 in the huperzine A group, all lower than that in the normal control group (2.210 +/- 0.074, all P < 0.01). CONCLUSION: PNS higher than 100 mg/kg could decrease the activity of BACE1 and down-regulate the content of BACE1 protein in the brain of SAMP8 mice.

[Study on the effect of extracts from the leaves of Phyllanthus emblica on immune function of mice].

OBJECTIVE: To explore the effect of extracts from the leaves of Phyllanthus emblica (PLFs) on the immune function of mice. METHODS: 70 Kunming mice were choosed to conduct the acute toxicity test of PLFs. The mice were randomly divided into four groups: PLFs high-dosage group, mid-dosage group, low-dosage group and control group. The high,mid,low-dosage groups were treated with PLFs 1.982, 0.991 and 0.496 g/kg respectively per day. The same volume of double distilled water was given to the control group. All by intragastric administration for 7 d. The animals were killed and indexes of thymus and spleen were calculated. The expurgation index K and phagocyte index a were detected after the mice being injected with a dilute India ink through caudal vein. In addition, prepared spleen cells conventionally,the activity of Natural Killer cells was measured and the proliferation of T and B cells were detected. The effect of the extracts on serum hemolysin was detected after the SRBC was injected into the enterocoelia. RESULTS: The LD50 of PLFs was 9. 911 g/kg. Compared with the control group, the indexes of thymus and spleen in the treatment groups had no markedly difference (P > 0.05). The high- and mid-dosage groups could obviously improve the expurgation index K (P < 0.05), phagocyte index alpha (P < 0.05) and NK cell activity (P < 0.05). CONCLUSION: The extracts from Phyllanthus emblica leaves can promote nonspecific immunity immune function in mice.

Gliclazide Ameliorates Neuronal Injury by Attenuating Oxidative Stress in D-gal-Induced Senescent Cells and Aging Mice.

Enhancement of oxidative stress and resultant neuronal injury play important roles in initiating cognitive impairment during the aging process. Thus, attenuating oxidative injury is regarded as a profitable therapeutic strategy for age-associated cognitive impairment. Previous studies showed that gliclazide (Gli) had a protective role in neuronal injury from cerebral ischemia/reperfusion (I/R) injury. However, whether Gli has a profitable effect on age-associated cognitive impairment remains largely unclear. The present study showed that Gli held the potential to attenuate neuronal apoptosis in D-gal-induced senescent cells and aging mice. Additionally, Gli could alleviate synaptic injury and cognitive function in D-gal-induced aging mice. Further study showed that Gli could attenuate oxidative stress in D-gal-induced senescent cells and aging mice. The p38 MAPK pathway was predicted as the downstream target of Gli retarding oxidative stress using in silico analysis. Further studies revealed that Gli attenuated D-gal-induced phosphorylation of p38 and facilitated Nrf2 nuclear expression, indicating that the anti-oxidative property of Gli may be associated with the p38 MAPK pathway. The study demonstrates that Gli has a beneficial effect on ameliorating D-gal-induced neuronal injury and cognitive impairment, making this compound a promising agent for the prevention and treatment of age-associated cognitive impairment.

[Effect of Panax notoginseng saponins on expression of alpha-secretase mRNA in brains of senescence-accelerated SAMP8 mice].

OBJECTIVE: To study the effect of Panax notoginseng saponins (PNS) on expression of alpha-aecretase mRNA in the brains of senescence-accelerated SAMP8 mice. METHOD: SAMP8 mice were randomly divided into the control group, the PNS high-dosage group (200 mg x kg(-1)), the PNS low-dosage group (100 mg x kg(-1)) and the huperzine A group (0.3 mg x kg(-1)), with eight mice in each group. The control group and each administration group were orally administered with the same volume of double distilled water once for consecutively two months. The expression of alpha-secretase (ADAM 9, ADAM10, ADAM17) mRNA was assayed by real-time fluorescence quantitative polymerase chain reaction (Real-time PCR). RESULT: The expression of ADAM9 mRNA in PNS high-dosage group and huperzine A group were significantly higher than that of the control group (P < 0.05). The expression of ADAM10 in the PNS high-dosage group, the PNS low-dosage group and the huperzine A group showed no significant difference from the control group. CONCLUSION: PNS can up-regulate expressions of ADAM9 mRNA and down-regulate expressions of ADAM10 mRNA in the brains of SAMP8 mice.

[The effect of PNS on the content and activity of alpha-secretase in the brains of SAMP8 mice with alzheimer's disease].

OBJECTIVE: To explore the effects of PNS on the content and activity of alpha-secretase in the brains of SAMP8 mice with Alzheimer's disease. METHODS: SAMP8 mice were randomly divided into four groups: PNS high-dosage group, PNS low-dosage group, huperzine A group and control group. The high-dosage group and low-dosage group were treated with 200 and 100 mg/kg PNS respectively per day and the huperzine A group was treated with 0.3 mg/kg huperzine A per day, all by intragastric administration for 8 consecutive weeks. The same volume of double distilled water was given to the control group. The activity of a-secretase was assayed by direct immunofluorescent method(DIF). Western blot was used to detect the content of alpha-secretase including ADAM9, ADAM10 and ADAM17 proteins. RESULTS: The Relative Fluorescence Units (RFU) of PNS high-dosage and low-dosage groups were higher than that of control group (P < 0.01). The results of western blot showed that the level of ADAM9 protein expression in PNS high-dosage, low-dosage and huperzine A groups was significantly higher than that of control group (P < 0.05) while the levels of ADAM10 protein expression in PNS high-dosage, low-dosage and huperzine A groups was significantly lower than that of control group (P < 0.05), while level of ADAM17 of huperzine A group was higher than that of control group (P < 0.05). CONCLUSION: PNS can increase activity of alpha-secretase in the brain of SAMP8 mouse via increasing the level of ADAM9 protein expression.

[Study of galic acid extracted from the leaves of Phyllanthus emblica on apoptotic mechanism of human hepatocellular carcinoma cells BEL-7404].

OBJECTIVE: To explore the mechanism of apoptosis of human hepatocellular carcinoma cells BEL-7404 induced by Galic acid extracted from leaves of Phyllanthus emblica. METHODS: PI/Hoechst33342 double staining method was utilized to observe the influence on cell life cycle. The expressions of Bax and Bcl-2 protein were determined by fluorescence immunostaining and Western blot. RESULTS: The results from PI/Hoechst33342 double staining method indicated that the percentage of cells G2/M phases increased after treated for 72 h, the phenomenon of blockage appeared and cell death was induced. Fluorescence immunostaining showed that the expression of Bax was up-regulated, and the expression of Bcl-2 was down-regulated. Western blot also showed that the the expression of Bax was up-regulated. CONCLUSION: The mechanism of human hepatoma BEL-7404 cells apoptosis induced by Galic acid from leaves of Phyllanthus emblica may be blocking G2/M period in cell life cycle, up-regulating the expression of Bax and down-regulating the expression of Bcl-2, that can decrease membrane potential of mitochondria,and triggered the caspases of activation of cascade and induced cell death.

[Effect of Panax notoginseng saponins on APP gene transcription in the brain tissue of SAMP8].

OBJECTIVE: To study the effect of Panax notoginseng saponins (PNS) on learning and memory ability and APP gene transcription in the brain tissue in senescence accelerated mouse prone 8 (SAMP8). METHODS: SAMP8 were randomly divided into high-does PNS group, low-does PNS group, huperzin A group and model group,the treatment groups were treated with the designed drugs respectively by intragastric administration for 4 consecutive weeks. The same volume of double distilled water was given to model group. After treatment, the abilities of learning and memory of the mice were tested with morris water maze, the mRNA content of APP was assayed by reverse transcription (RT) and real-time polymerase chain reaction (RT-PCR). RESULTS: PNS could improve the abilities of learning and memory, high-does PNS could reduce the mRNA content of APP in the brain tissue of SAMP8. CONCLUSION: PNS can improve the abilities of learning and memory of SAMP8, the mechanism may be relevant to down-regulating the expression of APP gene at transcriptional level.

Functional roles of the microbiota-gut-brain axis in Alzheimer's disease: Implications of gut microbiota-targeted therapy.

Increasing scientific evidence demonstrates that the gut microbiota influences normal physiological homeostasis and contributes to pathogenesis, ranging from obesity to neurodegenerative diseases, such as Alzheimer's disease (AD). Gut microbiota can interact with the central nervous system (CNS) through the microbiota-gut-brain axis. The interaction is mediated by microbial secretions, metabolic interventions, and neural stimulation. Here, we review and summarize the regulatory pathways (immune, neural, neuroendocrine, or metabolic systems) in the microbiota-gut-brain axis in AD pathogenesis. Besides, we highlight the significant roles of the intestinal epithelial barrier and blood-brain barrier (BBB) in the microbiota-gut-brain axis. During the progression of AD, there is a gradual shift in the gut microbiota and host co-metabolic relationship, leading to gut dysbiosis, and the imbalance of microbial secretions and metabolites, such as lipopolysaccharides (LPS) and short-chain fatty acids (SCFAs). These products may affect the CNS metabolic state and immune balance through the microbiota-gut-brain axis. Further, we summarize the potential microbiota-gut-brain axis-targeted therapy including carbohydrates, probiotics, dietary measures, and propose new strategies toward the development of anti-AD drugs. Taken together, the data in this review suggest that remodeling the gut microbiota may present a tractable strategy in the management and development of new therapeutics against AD and other neurodegenerative diseases.

[Effect of Panax notoginseng saponins on syp and tau gene expression in brain of senescence accelerated mouse].

OBJECTIVE: To study the effect of Panax notoginseng saponins (PNS) on (synaptophysin, syp) and tau gene expression in the brain tissue in senescence accelerated mouse prone 8 (SAMP 8). METHOD: SAMP8 were randomly divided into 4 groups: PNS 23.38, 93.50 mg x kg(-1) group, huperzin A 0.038 6 mg x kg(-1) x d(-1) group and blank control group; the drug groups were treated with the designed drugs respectively per day by intragastric administration for 4 consecutive weeks, and double distilled water was given to blank control group. After treatment, the mRNA content of tau and syp were assayed by reverse transcription (RT) and real-time polymerase chain reaction (real-time PCR). RESULT: Compared with blank control group, the syp mRNA contents were increased in PNS groups (P < 0.05 or P < 0.01), and the tau mRNA content were not significant difference in all groups. CONCLUSION: This study suggests that PNS can up-regulate syp gene expression at transcriptional level in the brain of SAMP 8.

[Analysis of essential oil from the leaves and fruits of Eucalyptus tereticornis in Guangxi province by GC-MS].

OBJECTIVE: To Analyze the chemical composition and their relative contents of essential oil from the leaves and fruits of Eucalyptus tereticornis in Guangxi province. METHODS: The column temperature was controlled by a program with a capillary column HP-5 MS, and the MS analysis was performed with EI and quadrupole mass analyzer. The chemical compositions were identified by NIST98 searching and mass spectra comparing, and their relative contents were determined by using normalization method of chromatographic peak areas. RESULTS: 39 compounds constituting 96.69% of the oil of leaves were identified. The major components were eucalyptol (27.93%), 1R-alpha-pinene (22.60%), isopinocarveol (8.71%); 36 compounds constituting 93.50% of the oil of fruits were identified. The major components are 1R-alpha-pinene (32.88%), eucalyptol (13.64%), D-limonene (8.31%). CONCLUSION: The GC-MS is a simple, rapid and sensitive method.

[Inhibitive effects of Panax notoginseng saponins on expression of Abeta(1-40), Abeta(1-42) protein in SAMP8's brain].

OBJECTIVE: To observe inhibitive effects of Panax notoginseng saponins on expression of Abeta(1-40), Abeta(1-42) protein in SAMP8's brain. METHODS: Amount of Abeta(1-40), Abeta(1-42 immuno-positive neurons was detected in parietal cortex and hippocamp in their brains under high power lens (40 x) by immunohistochemistry analysis. RESULTS: PNS could reduce the amount of Abeta(1-40), Abeta(1-42) protein in parietal cortex and hippocamp. CONCLUSION: PNS can reduce the amount of Abeta(1-40), Abeta(1-42) protein in SAMP8's brain.

[The effect of gallic acid extracted from leaves of Phyllanthus emblica on apoptosis of human hepatocellular carcinoma BEL-7404 cells].

OBJECTIVE: To explore the effect of gallic acid extracted from Leaves of Phyllanthus emblica on the apoptosis of BEL-7404 cells. METHODS: MTT assay was applied to detect the influence on prolifetation in vitro. Inverted microscope was utilized to observe the morphological changes after BEL-7404 cells were treated with gallic acid. Annexin V/PI double label method was used to detect earlier period apoptosis cells and Tunel was applied to calculate the apoptosis rates. RESULTS: Gallic acid could restrain the BEL-7404 cells proliferation at diffierent levels in a time and concentration dependent manner. The typical morphological changes of apoptosis were observed after BEL-7404 cells were treated with gallic acid. Annexin V/PI double label method and Tunel method showed that the viable apoptotic cell and apoptosis rates added as action time prolonged. CONCLUSION: Gallic acid can restrain the BEL-7404 cells proliferation and induce apoptosis, and its effect on apoptosis is time dependent.

Probucol, a "non-statin" cholesterol-lowering drug, ameliorates D-galactose induced cognitive deficits by alleviating oxidative stress via Keap1/Nrf2 signaling pathway in mice.

Oxidative stress plays a vital role in the initiation and progression of age-related neurodegenerative diseases. Ameliorating oxidative damage is therefore considered as a beneficial strategy for the treatment of age-related neurodegenerative disorders. Probucol (Prob), a lipid-lowering prototype agent, was reported to treat cardiovascular diseases, chronic kidney disease and diabetes mellitus. However, whether Prob has an effect on age-related neurodegenerative diseases remains unknown. In the study, it was found that Prob ameliorated D-galactose (D-gal) induced cognitive deficits and neuronal loss in the hippocampal CA1 region. Moreover, Prob alleviated ROS and MDA levels by elevating SOD, GSH-PX and HO-1 mRNA and protein expressions, and improving plasmic and cerebral SOD and GSH-PX activities in D-gal treated mice. Furthermore, Prob promoted the dissociation of Keap1/Nrf2 complex leading to the accumulation of Nrf2 in nucleus, implying that the improved anti-oxidant property of Prob is mediated by Keap1/Nrf2 pathway. The study firstly demonstrates the favorable effects of Prob against cognitive impairments in a senescent mouse model, rendering this compound a promising agent for the treatment or prevention of age-related neurodegenerative disease.

[Experimental study on antitumor effect of extracts from Cestrum nocturnum in vivo].

OBJECTIVE: To observe the antitumor effects of extracts from Cestrum nocturnum (CN) in vivo. METHODS: The S180-mice model was used to observe the tumor-inhibition rate of CN and the H22-mice model was used to test the survival time. RESULTS: The experiment in S180-mice demonstrated that the n-butanol and polysaccharides extracts from CN had obvious effects on tumor inhibition. Its inhibitory rates were 52.30%, 46.75%, 42.28%, 43.19%, 37.96% and 31.82% respectively in the mice administrated the n-butanol and polysaccharides extracts from CN with 30 mg/kg, 20 mg/kg and 15 mg/kg weight dosage. It was noted that tumor formation postponed in mice treated with the n-butanol and polysaccharides extracts from CN compared with the control panel and tumor growth became slower; The n-butanol and polysaccharides extracts from CN could also greatly enhance the life span of mice with H22 ascitic tumors by 116.43%, 44.52%, 20.54%, 109.52%, 112.61% and 115.01%, respectively. The inhibit effects of n-butanol fraction extracts from CN had direct relationship with dose, while the polysaccharides fraction extracts from CN had no obvious relationship with dose. CONCLUSION: The n-butanol and polysaccharides extracts of CN are able to inhibit tumor growth and prolong the lifetime of the tumor-bearing mice in a dose-dependent pattern.