Molluscicidal and Mosquitocidal Activities of the Essential oils of Thymus capitatus Hoff. et Link. and Marrubium vulgare L.

A destilação por arraste a vapor dos óleos essenciais de partes aéreas de Thymus capitatus Hoff. et Link. e de Marrubium vulgare L. coletadas na costa norte do Egito resultaram em rendimento de 0,5% e 0,2%, respectivamente. Resultados de análises por cromatografia gasosa acoplada à espectrometria de massas de ambas as amostras possibilitaram a identificação de 96,27% e 90,19% dos constituintes químicos respectivamente de T. capitatus e M. vulgare. Verificou-se predomínio de constituintes oxigenados (88,22% para T. capitatus e 57,50% para M. vulgare, principalmente fenóis, como carvacrol (32,98%) e timol (32,82%) no óleo essencial de T. capitatus, e timol (34,55%) no óleo essencial de M. vulgare. Avaliou-se a atividade dos óleos essenciais obtidos contra adultos e ovos de Biomphalaria alexandrina, bem como em larvas e pupas de Culex pipiens. A CL50 e CL90 do óleo essencial de T. capitatus em moluscos adultos foi respectivamente 200 e 400 ppm/3hrs, enquanto para o óles essencial de M. vulgare verificou-se CL50 e CL90 de 50 e 100 ppm/3hrs, respectivamente. Além disso, M. vulgare apresentou atividade ovicida, com CL 100 de 200 ppm/24 horas, enquanto o óleo essencial de T. capitatus não demonstrou atividade ovicida. Verificou-se ainda atividade mosquitocida, com CL50 e CL90 de 100 e 200 ppm/12hrs respectivamente para larvas, e 200 e 400 ppm/12hrs contra pupas de C. pipiens.Steam distillation of essential oils of aerial parts of Thymus capitatus and Marrubium vulgare L. collected at North cost of Egypt yielded 0.5% and 0.2%, respectively. Results of Gas chromatography-mass spectrometry analyses of the two samples identified 96.27% and 90.19% of the total oil composition for T. capitatus and M. vulgare, respectively. The two oil samples appeared dominated by the oxygenated constituents (88.22% for T. capitatus and 57.50% for M. vulgare), composed of phenols, mainly carvacrol (32.98%) and thymol (32.82%) in essential oil of T. capitatus, and thymol (34.55%) in essential oil of M. vulgare. It was evaluated the molluscicidal activity of T. capitatus and M. vulgare essential oils on adult and eggs of Biomphalaria alexandrina as well as their mosquitocidal activity on Culex pipiens. The LC50 and LC90 of T. capitatus essential oil against adult snails was 200 and 400 ppm/3hrs, respectively, while for M. vulgare it was 50 and 100 ppm/3hrs, respectively. Moreover, M. vulgare showed LC100 ovicidal activity at 200 ppm/24 hrs while T. capitatus oil showed no ovicidal activity. It was verified mosquitocidal activity, with LC50 and LC90 of 100 and 200 ppm/12hrs respectively for larvae, and 200 and 400 ppm/12hrs respectively for pupae of C. pipiens

Toxoplasma gondii: Prolonged in-vitro maintenance of virulent tachyzoites in fluid media at low temperatures

Background: Prolonged maintenance of infective Toxoplasma gondii tachyzoites (T.g.T.) is an important subject for research purposes. This study aimed to evaluate four serum free fluid media for prolonged in vitro maintenance of T.g.T.Methods: The four fluid media Phosphate buffered saline (PBS) pH 7.2 and Roswell Park Memorial Institute (RPMI-1640) with or without 3% fetal bovine serum (FBS) were evaluated for maintenance of virulent T.g.T. The four media were tested after incubation at three different temperature degrees in the darkness.Results: Prolonged maintenance period for infective T.g.T. was recorded especially in the absence of FBS supplement. RPMI without FBS was able to maintain infective T.g.T. for 16 days post incubation (dpi) at refrigerator temperature. This period decreased to 10 dpi and 6 dpi after incubation in the same media at 18–22 oC and 37 oC, respectively. Cultivation of T.g.T. in RPMI supplemented with 3% FBS and in PBS proved to maintain infective T.g.T. for 14 dpi at refrigerator temperature, and for 9 and 5 dpi when the two media were incubated at 18–22 oC and 37 oC, respectively. Shorter periods for keeping the T.g.T. infectivity were recorded using PBS supplemented with 3% FBS under all tested temperature conditions.Conclusion: This method allows economic long-lasting maintenance of tachyzoites for 16th dpi in RBMI that can be reactivated by reinoculation in mice.Keywords:  Toxoplasma gondii, Tachyzoites, Fluid media, Temperatur

Serological evidence of association between Helicobacter pylori infection and coronary artery disease

Background: Studies have reported relationship between chronic  Helicobacter pylori infection and coronary artery disease (CAD). The  cytotoxin-associated gene A product (CagA) is an immunodominant protein which indicates infection with virulent H. pylori strains. Significant  associations of CagA-positive H. pylori strains with coronary artery disorders have been widely reported. H. pylori is also known to produce different heat shock proteins (HSPs) which can stimulate the production of specific  antibody against microbial proteins and capable of eliciting autoimmune reaction against human tissue expressing HSPs such as vascular  endothelial cells. The objectives of this study are to investigate the  association between H. pylori and CagA with coronary atherosclerosis and CAD, and to determine the possible role of H. pylori HSP60 protein in increasing the risk of CAD development. Methods: This study included 70 patients with stable angina and 70 age and gender-matched controls. Each group was evaluated by clinical history, physical examination, cardiac echocardiography (ECHO) and electrocardiography (ECG) with and without exercise. Fasting blood glucose, total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL) and triglycerides (TG) were estimated by automated enzymatic methods. H. pylori IgG, CagA IgG and HSP60 IgG were measured by enzyme-linked immunosorbent assay (ELISA) for both groups. Results: The seroprevalence of H. pylori infection was high in both groups; 75.7% in case and 68.6% in control (p=0.346). Serum IgG levels were significantly higher for CagA (p=0.028) and HSP60 (p<0.001) in cases than in controls. There was significant association between H. pylori and CagA IgGs in cases (p=0.007) but no association in controls (p=0.700). Higher HSP60 IgG level was significantly associated with both positive H. pylori IgG (p<0.001) and CagA IgG (p<0.001) in cases but no significant association was found with H. pylori (p=0.815) or CagA (p=0.332) IgG levels in the control group. Serum values were significantly higher for TC (p<0.001), TG (p<0.001) and LDL (p=0.004) while value for HDL was significantly lower (p<0.001) in H. pylori IgG-positive subjects (case and control). Conclusion: There is serological evidence that H. pylori infection may pose a significant risk factor for CAD. Since H. pylori can be eliminated by specific treatment, this may be a good preventive approach for CAD.Key words: H. pylori, coronary artery disease, CagA, HSP60, serology

A STUDY ON THE DIFFERENTIATION BETWEEN ORANGE TREES DIRECTIONS ON THE CITRUS LEAFMINER, PHYLLOCNISTIS CITRELLA STAINTON (LEPIDOPTERA: GRACILLARIIDAE) AND THE COMMON PREDATORY SPECIES, IN QALUOBIYA GOVERNORATE

Field studies were carried out to study the effect of the different four directions (East, West, North and South) and the middle of the orange trees on the occurrence of the citrus leafminer, Phyllocnistis citrella Staint. (Lepidoptera: Gracillariidae), attacking orange orchards during the period extended from the beginning of July, 2015 until the end of June 2016. Also, to determine the common predatory species occurred in navel orange orchards in Qaluobiya Governorate. The warmer months that have the highest temperature degrees and that months having the newly orange leaves, had the highest percentages of infestation by the pest. The obtained results revealed that, the South direction of the orange trees had the highest percentages of leaves damage by the citrus leafminer, P. citrella. Where, there were significant differences between the South direction (68.75%), in comparing with those of the West direction (64.42%), the North direction (60.58%), the East direction (54.58%) and the middle of the orange trees (45.38%). So, it is recommended to firstly begin the Integrated Pest Management (IPM) programs against the pest in this direction and at the suitable time. Moreover, the importance of the natural role of the common predatory species recorded in the orange orchard is obviously shown and must be encouraged and developed. The highest total numbers of all recorded predatory species were during July, 2015 (47 individuals) and April, 2016 (35 individuals). The recorded predatory species were the highest in the South direction (70 individuals), in comparing with those of the North direction (54), the East direction (50), the West direction (37) and the middle of the orange trees (20). True spiders were recorded as the most predators (114 individuals), in orange orchard and also in the same time of pest occurrence. The animal predatory species (true spiders and predatory mites) were the highest in their numbers (167 individuals), in comparing to the insect predatory species: Chrysoperla carnea, Scymnus sp., Coccinella undecimpunctata, Orius sp. and Metasyrphus sp., of lower individuals numbers (64 individuals). In general, from this study, it is also recommended to use the different predatory species such as: Chrysoperla carnea, Scymnus sp., Coccinella undecimpunctata and Orius sp., for P. citrella control firstlyfrom the South direction. Where, this pest controlcan be applied by mass rearing of these predators in the laboratory and releasing them in orange orchards against P. citrella or other related pests (such as the citrus aphids species and mealybugs). This approach is believed to be highly practical for use as one of the means of biological control with the frame work of suitable and safe IPM programs in citrus orchards in Egypt

Preparation of La0.7Ca0.3Mn0.95Fe0.05O3 perovskites by different methods: Catalytic activity towards the hydroxylation of benzene

Nanoparticles of the La0.7Ca0.3Mn0.95Fe0.05O3 perovskites were synthesized by various wet chemical routes, namely, co-precipitation, oxalate-gel and citrate-gel methods. Phase formation and crystal structure of the synthesized powders were examined by the X-ray diffraction (XRD). The morphology was evaluated by the scan electron microscopy (SEM). Infrared transmission spectroscopy revealed that stretching and bending modes were influenced by the preparation methods. The citrate gel method yielded better powder properties. The prepared perovskite samples were used in the oxidation of benzene. The highest activity for the catalytic oxidation of benzene to phenol in presence of hydrogen peroxide (H2O2) was obtained with the citrate-gel prepared sample

Molecular marker dissection of stem rust resistance in Nebraska bread wheat germplasm

Stem rust (caused by Puccinia graminis f. sp. tritici) is a major disease of wheat. To understand the genetic basis of stem rust resistance in Nebraska winter wheat, a set of 330 genotypes representing two nurseries (DUP2015 and TRP2015) were evaluated for resistance to a Nebraska stem rust race (QFCSC) in two replications. The TRP2015 nursery was also evaluated for its resistance to an additional 13 stem rust races. The analysis of variance revealed significant variation among genotypes in both populations for stem rust resistance. Nine stem rust genes, Sr6, Sr31, Sr1RSAmigo, Sr24, Sr36, SrTmp, Sr7b, Sr9b, and Sr38, were expected and genotyped using gene-specific markers. The results of genetic analysis confirmed the presence of seven stem rust resistance genes. One genotype (NE15680) contained target alleles for five stem rust resistance genes and had a high level of stem rust resistance against different races. Single marker analysis indicated that Sr24 and Sr38 were highly significantly associated with stem rust resistance in the DUP2015 and TRP2015 nurseries, respectively. Linkage disequilibrium analysis identified the presence of 17 SNPs in high linkage with the Sr38-specific marker. These SNPs potentially tagging the Sr38 gene could be used in marker-assisted selection after validating them in additional genetic backgrounds

Determination of the tensile properties and biodegradability of cornstarch-based biopolymers plasticized with sorbitol and glycerol

In this study, the effects of various quantities of sorbitol and glycerol plasticizers (0%, 30%, 45%, and 60%) on cornstarch-based film were examined to develop a novel polymer for usage with biodegradable materials. The film was prepared using the casting process. According to the test findings, the application of the plasticizer concentrations affected the thickness, moisture content, and water absorption of the film. When plasticizer concentrations were increased to 60%, the tensile stress and Young’s modulus of plasticized films dropped regardless of plasticizer type. However, the thin film with addition of 30% sorbitol plasticizer demonstrated a steady value of Young’s modulus (60.17 MPa) with an increase in tensile strength (13.61 MPa) of 46%, while the lowest combination of tensile strength and Young’s modulus is the film that was plasticized with 60% glycerol, with 2.33 MPa and 16.23 MPa, respectively. In summary, the properties and performance of cornstarch-based film were greatly influenced by plasticizer types and concentrations. The finest set of features in this research appeared in the film plasticized with 30% sorbitol, which achieved the best mechanical properties for food packaging applications

Vertically Aligned Silicon Carbide Nanowires/Boron Nitride Cellulose Aerogel Networks Enhanced Thermal Conductivity and Electromagnetic Absorbing of Epoxy Composites

With the innovation of microelectronics technology, the heat dissipation problem inside the device will face a severe test. In this work, cellulose aerogel (CA) with highly enhanced thermal conductivity (TC) in vertical planes were successfully obtained by constructing a vertically aligned silicon carbide nanowires (SiC NWs)/boron nitride (BN) network via the ice template assisted strategy. The unique network structure of SiC NWs connected to BN ensures that the TC of the composite in the vertical direction reaches 2.21 W/(m·K) at a low hybrid filler loading of 16.69 wt, which was increased by 890 compared to pure epoxy (EP). In addition, relying on unique porous network structure of CA, EP based composite also showed higher TC than other comparative samples in the horizontal direction. Meanwhile, the composite exhibits good electrically insulating with a volume electrical resistivity about 2.35×1011 Ω·cm, and displays excellent electromagnetic wave absorption performance with a minimum reflection loss of -21.5 dB and a wide effective absorption bandwidth (< -10 dB) from 8.8 to 11.6 GHz. Therefore, this work provides a new strategy for manufacturing polymer-based composites with excellent multifunctional performances in microelectronic packaging applications

Genome-Wide Association Study for Identification and Validation of Novel SNP Markers for \u3ci\u3eSr6\u3c/i\u3e Stem Rust Resistance Gene in Bread Wheat

Stem rust (caused by Puccinia graminis f. sp. tritici Erikss. & E. Henn.), is a major disease in wheat (Triticum aestivium L.). However, in recent years it occurs rarely in Nebraska due to weather and the effective selection and gene pyramiding of resistance genes. To understand the genetic basis of stem rust resistance in Nebraska winter wheat, we applied genome-wide association study (GWAS) on a set of 270 winter wheat genotypes (A-set). Genotyping was carried out using genotyping-by-sequencing and ~35,000 high-quality SNPs were identified. The tested genotypes were evaluated for their resistance to the common stem rust race in Nebraska (QFCSC) in two replications. Marker-trait association identified 32 SNP markers, which were significantly (Bonferroni corrected P \u3c 0.05) associated with the resistance on chromosome 2D. The chromosomal location of the significant SNPs (chromosome 2D) matched the location of Sr6 gene which was expected in these genotypes based on pedigree information. A highly significant linkage disequilibrium (LD, r2) was found between the significant SNPs and the specific SSR marker for the Sr6 gene (Xcfd43). This suggests the significant SNP markers are tagging Sr6 gene. Out of the 32 significant SNPs, eight SNPs were in six genes that are annotated as being linked to disease resistance in the IWGSC RefSeq v1.0. The 32 significant SNP markers were located in nine haplotype blocks. All the 32 significant SNPs were validated in a set of 60 different genotypes (V-set) using single marker analysis. SNP markers identified in this study can be used in marker-assisted selection, genomic selection, and to develop KASP (Kompetitive Allele Specific PCR) marker for the Sr6 gene