Effects of Silver Nanoparticles on the Activities of Soil Enzymes Involved in Carbon and Nutrient Cycling     

Frieda EIVAZI  Zahra AFRASIABI  Elizabeth JOSE 《土壤圈》2018,28(2):209-214

Soils are continuously exposed to large amounts of engineered nanoparticles, especially silver nanoparticles (AgNPs), which can affect the activity, stability, and specificity of microbial enzymes. Therefore, the measurement of specific enzyme activity can be used to identify major changes in soil environments. Accordingly, the aim of the present study was to investigate the effects of AgNPs on soil enzymes that play critical roles in mineralizing carbon and nutrients in soil. Soil samples (silt loam and sandy loam) were collected from the surface layer (0–15 cm) of a field at the George Washington Carver Farm, Lincoln University of Missouri, USA. The soils were then treated with AgNP solutions at 0, 1 600, or 3 200 μg Ag kg~(-1) dry soil, using either 10- or 50-nm AgNPs and a randomized complete block design, with three replicates per treatment. The AgNP-treated soil samples were homogenized and incubated for one month, and soil acid phosphatase, β-glucosaminidase, β-glucosidase, and arylsulfatase activities were measured after one hour, one week, and one month of incubation. The activities of all four enzymes were reduced by AgNP treatment after one hour and one week.However, AgNP size had no effect. After one month of incubation, the AgNP treatments had mixed effects, which suggests that soil enzymes are only affected on a short-term basis. Further studies are required to determine the mechanisms by which AgNPs reduce soil enzyme activity.  相似文献   

Induction of insulin resistance by malathion: Evidence for disrupted islets cells metabolism and mitochondrial dysfunction     

Shirin Pournourmohammadi  Seyed Nasser Ostad  Mohammad Hossein Ghahremani  Bagher Minaie  Mohammad Abdollahi 《Pesticide biochemistry and physiology》2007,88(3):346-352

Hyperglycemia is observed with exposure to organophosphorus (OP) pesticides. The aim of this study was to investigate the effects of malathion on secretion of insulin from rat pancreatic islets in vitro and in vivo. Malathion was administered through food for 4 weeks at concentrations of 100, 200, and 400 ppm. For in vivo experiment, at the end of treatment, blood sample was obtained and plasma was separated. For in vitro experiment, the treated rats were anesthetized and underwent a laparatomy. The common bile duct was cannulated and the pancreas distended by injecting of cold collagenase V using peristaltic infusion pump. Islets were then hand picked under a stereomicroscope and cultured in the presence of various doses of glucose and KCl. Malathion at doses of 200 and 400 ppm increased plasma glucose and insulin concentrations and lowered activity of erythrocyte acetylcholinesterase. The isolated islets from pretreated animals with malathion 200 and 400 ppm showed lower glucose-stimulated insulin secretion while no change was observed in the presence of KCl. Light microscopic examination revealed that malathion causes patchy degenerative changes in pancreatic islets. Combination of in vivo and in vitro findings suggests that malathion induces a kind of insulin resistance that cannot overwhelm hyperglycemia. This action of malathion is mediated through disruption of islets mitochondrial function.  相似文献   

Determination of Chilling and Heat Requirements of Pistachio （Pistacia vera L.） Cultivars     

Majid Rahemi  Zahra Pakkish 《中国农业科学(英文版)》2009,8(7):803-807

Determination of chilling and heat requirements of pistachio （Pistacia vera L.） cultivars is important for satisfactory growth and development, particularly when large-scale commercial production is desired. This experiment was conducted to determine chilling requirement inducing vegetative and flower buds of Kalle-Ghuchi, Owhadi, Ahmad-Ahgaei, and Akbari pistachio. Shoots with enough vegetative and flower buds were taken from pistachio trees during autumn 2007 and 2008 when temperature reached to 15°C. Cuttings with flower buds were kept under （5 ± 1）°C for 0, 600, 650, 700, 750, 800, 850, 900, 950, 1 000, 1 050, 1 100, 1 150, 1 200, 1 250, and 1 300 h, respectively, and cuttings with vegetative buds were kept at 51°C until 1 500 h. The results indicated that pistachio cultivars requite chilling time between 750-1 400 h and heat requirements between 8 852-15 420 growing degree hours （GDH）. Consequently, Kalle-Ghuchi had the lowest chilling （750-950 h）, and heat （8 852-9 768 GDH） requirements, Ahmad-Aghaei and Owhadi had intermediate （1 000-1 250 h, 10 656- 13 320 GDH） and Akbari had the highest chilling （1 200-1 400 h） and heat （11 863-15 420 GDH） requirement.  相似文献   

Field and controlled conditions screenings of some faba bean (Vicia faba L.) genotypes for resistance to the parasitic plant Orobanche crenata Forsk. and investigation of involved resistance mechanisms     

Briache  Fatima Zahra  Ennami  Mounia  Mbasani-Mansi  Joseph  Gaboun  Fatima  Abdelwahd  Rabha  Fatemi  Zain El Abidine  El-Rodeny  Walid  Amri  Moez  Triqui  Zine El Abidine  Mentag  Rachid 《植物病害和植物保护杂志》2019,126(3):211-224

Journal of Plant Diseases and Protection - The parasitic weed Orobanche crenata is a serious constraint to legumes crops in Mediterranean area. In Morocco, heavy O. crenata infestation level was...  相似文献   

Suppression of telomerase activity by pyrimethamine: implication to cancer     

Khorramizadeh MR  Saadat F  Vaezzadeh F  Safavifar F  Bashiri H  Jahanshiri Z 《Iranian Biomedical Journal》2007,11(4):223-228

BACKGROUND: Although pyrimethamine (Tindurin) appears to be effective in the prevention and treatment of some infectious diseases, very little information exists on its unpredictable properties. We design this study to evaluate its anti-tumoral effect on a model of cell line. METHODS: The cytotoxic influence of Pyrimethamine on prostate cell line was investigated using an in vitro colometric assay. The potential modulatory effects on metastasis, apoptosis, and immortality characteristics of cells were assessed with gelatin zymography, terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay and telomeric repeat amplification protocol, respectively. RESULTS: Cytotoxicity analysis of pyrimethamine revealed a dose-dependent fashion. An apoptotic influence of pyrimethamine was also confirmed by data obtained from TUNEL assay. Dose-dependent inhibitory effect on matrix metalloproteinases (MMP) was seen in pyrimethamine. A potent inhibitory effect of pyrimethamine was also established by data achieved from TRAPeze telomerase detection kit. CONCLUSIONS: Collectively, as induction of apoptosis together with MMP and telomerase inhibition could be indicative of cancer treatment, pyrimethamine might be considered as a chemopreventative agent in cancer.  相似文献   

Survey of the microbiological count of the milk collected from livestock ancient city of Garmsar,Semnan Province,Iran     

Hooshmand  Zahra  Teymouri  Pari  Safari  Mohammad  Soleimani  Zahra 《Tropical animal health and production》2020,52(1):195-201

Milk has a high nutritional value and can affect human health. Therefore, it is important to know the factors affecting its quality. The purpose of this study was to evaluate the raw milk microbial quality and factors affecting it. A total of 4260 raw cow milk samples, which were collected from villages around Garmsar city, Iran, and their microbial load were registered at Garmsar Dairy Cow Association between 2013 and 2014, was used in the present study. The total average ± SD of microbial load concentration was 3.02?×?10⁵?±?2.75?×?10⁵ (CFU/ml). The average concentration of total bacteria in 2013 was 2.73?×?10⁵?±?1.58?×?10⁵ (CFU/ml) and in 2014 it was 3.32?×?10⁵?±?3.93?×?10⁵(CFU/ml). Seasonally, it was 2.94?×?10⁵?±?1.72?×?10⁵ (CFU/ml), 3.69?×?10⁵?±?4.55?×?10⁵ (CFU/ml), 2.91?×?10⁵?±?1.62?×?10⁵ (CFU/ml), and 2.63?×?10⁵?±?1.67?×?10⁵ (CFU/ml) for spring, summer, autumn, and winter, respectively. There was a significant difference in seasonal average microbial concentration of milk samples (p?<?0.05). The present study concludes that microbial load of milk can be affected by environmental and hygienic conditions. Ranchers need to pay more attention to hygiene especially in warm seasons. Because in case of high microbial load in raw milk, even after milk pasteurization, it is not possible to have a high-quality and desirable product. Milk producers and distributors need also awareness in order to reduce the incidence of secondary contamination. But, the main correction is to establish direct supervision of the Ministry of Health onto the health of dairy cow farmers by structural integrity of Veterinary Medical Organization as the global one health.

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Salvia officinalis hydroalcoholic extract improved reproduction capacity and behavioral activity in rats exposed to immobilization stress     

Yasin Bagheri  Zahra Keshtmand  Reza Rahbarghazi  Mehrdad N. Gharamaleki  Alireza Barati  Sara Bagheri  Jafar Rezaie  Aysa Rezabakhsh  Mahdi Ahmadi  Masoud Delashoub 《Animal Science Journal》2020,91(1)

This study was conducted to evaluate the Salvia officinalis hydroalcoholic extract on fertility capacity and behavioral features in rats exposed to immobilization stress. Male rats were randomly divided into five groups; Control; Stressed rats; and Stressed rats received 50, 100 and/or 200 mg/kg bw S. officinalis hydroalcoholic extract. To induce stress, rats were immobilized for 49 days and received S. officinalis extract orally. On day 56, we analyzed behavioral tests and evaluated reproduction capacity by measuring LH, FSH, and testosterone. Sperm parameters such as motility, viability, and total count were also determined. Bodyweight changes were also calculated on day 56. Male rats from different groups were mated with healthy female rats. Data showed that the use of 100 and 200 mg/kg bw S. officinalis extract in stressed rats increased bodyweight gain and improved behavioral disorders compared to control‐matched groups (p < .05). Besides, administration of 100 and 200 mg/kg bw S. officinalis extract had the potential to improve sperm parameters and fertility capacity in stressed rats (p < .05). Decreased testosterone levels were blunted in the stressed rats that received plant extract coincided with the reduction of LH and FSH compared to control‐matched stressed rats (p < .05). We found neutral effects in stressed rats that received 50 mg/kg bw plant extract. Collectively, the hydroalcoholic extract of S. officinalis could improve the fertility capacity and behavioral features under stressful conditions in a dose‐dependent manner.  相似文献   

Modeling and Assessing of Electronic Readiness Among Agricultural Organization Workers: Case Study in Ardebil Province,Iran     

Zahra Daghighi Masouleh  Mohammad Sadegh Allahyari  Reza Ebrahimi Atani 《Journal Of Agricultural & Food Information》2014,15(4):295-310

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The genome of the African trypanosome Trypanosoma brucei     

Berriman M  Ghedin E  Hertz-Fowler C  Blandin G  Renauld H  Bartholomeu DC  Lennard NJ  Caler E  Hamlin NE  Haas B  Böhme U  Hannick L  Aslett MA  Shallom J  Marcello L  Hou L  Wickstead B  Alsmark UC  Arrowsmith C  Atkin RJ  Barron AJ  Bringaud F  Brooks K  Carrington M  Cherevach I  Chillingworth TJ  Churcher C  Clark LN  Corton CH  Cronin A  Davies RM  Doggett J  Djikeng A  Feldblyum T  Field MC  Fraser A  Goodhead I  Hance Z  Harper D  Harris BR  Hauser H  Hostetler J  Ivens A  Jagels K  Johnson D  Johnson J  Jones K  Kerhornou AX  Koo H 《Science (New York, N.Y.)》2005,309(5733):416-422

African trypanosomes cause human sleeping sickness and livestock trypanosomiasis in sub-Saharan Africa. We present the sequence and analysis of the 11 megabase-sized chromosomes of Trypanosoma brucei. The 26-megabase genome contains 9068 predicted genes, including approximately 900 pseudogenes and approximately 1700 T. brucei-specific genes. Large subtelomeric arrays contain an archive of 806 variant surface glycoprotein (VSG) genes used by the parasite to evade the mammalian immune system. Most VSG genes are pseudogenes, which may be used to generate expressed mosaic genes by ectopic recombination. Comparisons of the cytoskeleton and endocytic trafficking systems with those of humans and other eukaryotic organisms reveal major differences. A comparison of metabolic pathways encoded by the genomes of T. brucei, T. cruzi, and Leishmania major reveals the least overall metabolic capability in T. brucei and the greatest in L. major. Horizontal transfer of genes of bacterial origin has contributed to some of the metabolic differences in these parasites, and a number of novel potential drug targets have been identified.  相似文献   

Pre- and post-McDonald cerclage cervical length, width and funneling rate and their association with duration of pregnancy     

Azar ZF  Hakimi P  Ghojazadeh M  Ghatresamani F 《Pakistan journal of biological sciences: PJBS》2011,14(8):502-506

Changes of cervical ultrasonographic physical parameters and their association with outcome of cerclage have not been fully elucidated. This study aimed at evaluating association between ultrasonographic physical cervical shapes before and after McDonald cerclage with the length of pregnancy. Cervical length, width and funneling rate were assessed by transvaginal ultrasonography before and after the procedure. Mean pre-cerclage cervical length, width and funneling rate were 29.28 +/- 5.54, 19.92 +/- 10.30 mm and 12.90 +/- 18.87%, respectively. The mean post-cerclage cervical length, diameter and funneling rate were 31.68 +/- 4.21, 9.78 +/- 13.86 and 4.32 +/- 10.89%, respectively (p < 0.001 for all pre- and post-cerclage changes). The mean post-cerclage duration of pregnancy was 19.78 +/- 5.94 weeks. There were significant direct correlations between the pre-and post-cerclage cervical lengths with pregnancy duration (r = 0.24, p = 0.04 and r = 0.44, p < 0.001, respectively). There were significant indirect correlations between the pre- and post-cerclage funneling rate with pregnancy duration (r = -0.30, p = 0.01 and r = -0.20, p = 0.01, respectively). Similar correlations were not significant for the cervical widths. This study showed that the pre- and post-cerclage ultrasonographically determined cervical length and funneling are good predictors of pregnancy duration.  相似文献