Extraction Efficiency and HPLC Determination of Imidacloprid in Soil

Two extraction methods were successfully applied to study the extraction of imidacloprid from soil. The first method, using a mix of acetone and hexane, was based on Soxhlet extraction, and the second method, using acetonitrile, methanol, and water, was a modified version of a liquid extraction method. Quantification was performed by reversed-phase High Performance Liquid Chromatography (HPLC) with Diode Array Detection (DAD) at 270 nm using 40:60 (v/v) acetonitrile/water as a mobile phase. The mean recoveries for imidacloprid from soil ranged from 82.6 to 109%, with a relative standard deviation between 1.9 and 5.6% for both extraction methods. The detector linearity and the reproducibility of the method proved to be very precise. The limits of detection were 0.08 and 0.06 mg kg^?1 for liquid extraction and Soxhlet extraction, respectively. Overall, the efficiency of the Soxhlet extraction at lower concentrations was better than at higher concentrations, while liquid extraction proved efficient for all spiked levels. Liquid extraction performed better at higher concentrations compared to Soxhlet extraction. Taken together, our study suggests that the analysis of imidacloprid in soil can be performed with the modified liquid extraction method with a higher recovery and a lower RSD than Soxhlet extraction.     

Phylogenetic relationships among Artemisia species based on nuclear ITS and chloroplast psbA-trnH DNA markers

The taxonomic and phylogenetic relationships within the genus Artemisia s.l. (Asteraceae) are controversial, and it has been considered 1 to 8 different genera. This work re-investigated the phylogenetic relationships in Artemisia using nuclear ribosomal (ITS) and chloroplast psbA-trnH DNA sequences using three sections of Artemisia, Dracunculus, and Serphidium. Three phylogenetic trees were conducted separately on the basis of ITS, psbA-trnH and combined sequences using maximum parsimony. The results showed that the three sections were clearly separated from each other, and that the heterogamous Dracunculus and Artemisia are closely related to each other than either to homogamous Serphidium. This may suggest the taxonomic importance of capitulum morphology in Artemisia s.l. Our data also cast doubt on the use of cytogenetic similarity e.g., basic chromosome number in grouping Serphidium and Artemisia s.s. Furthermore, AMOVA analysis showed a higher level of ITS (55.29%) and combined ITS+cppsbA-trnH (55.63%) variations among sections. This provides further evidence for separation of these three sections and supports the phylogenetic results. The higher ITS nucleotide differences detected in Artemisia (30.4737) compared to very low value in Dracunculus (2.3333) and Serphidium (1.23077) may propose that the Artemisia comprises of several incipient sections. This supports the previous suggestion that Artemisia is a complex group.     

Dietary Intake of Whole and Refined Grain Breakfast Cereals and Weight Gain in Men

Objective: Prospective studies have suggested that substituting whole grain for refined grain products may lower the risk of overweight and obesity. Breakfast cereal intake is a major source of whole and refined grains and has also been associated with having a lower BMI. The aim of this study was to prospectively assess the association between whole and refined grain breakfast cereal intakes and risk of overweight (BMI ≥ 25 kg/m²) and weight gain. Research Methods and Procedures: We examined 17, 881 U.S. male physicians 40 to 84 years of age in 1982 who were free of cardiovascular disease, diabetes mellitus, and cancer at baseline and reported measures of breakfast cereal intake, weight, and height. Results: Over 8 and 13 years of follow‐up, respectively, men who consumed breakfast cereal, regardless of type, consistently weighed less than those who consumed breakfast cereals less often (p value for trend = 0.01). Whole and refined grain breakfast cereal intake was inversely associated with body weight gain over 8 years, after adjustment for age, smoking, baseline BMI, alcohol intake, physical activity, hypertension, high cholesterol, and use of multivitamins. Compared with men who rarely or never consumed breakfast cereals, those who consumed ≥1 serving/d of breakfast cereals were 22% and 12% less likely to become overweight during follow‐up periods of 8 and 13 years (relative risk, 0.78 and 0.88; 95% confidence interval, 0.67 to 0.91 and 0.76 to 1.00, respectively). Discussion: BMI and weight gain were inversely associated with intake of breakfast cereals, independently of other risk factors.     

Role of Selenium from Different Sources in Prevention of Pulmonary Arterial Hypertension Syndrome in Broiler Chickens

Pulmonary arterial hypertension (PAH) syndrome in broilers is associated with hypoxia, which prevails at high altitude. Oxidative stress is the pathogenic mechanism underlying PAH. Because selenium is key element in the structure of antioxidant enzymes, we evaluated pulmonary hypertensive responses in broiler chickens fed with diets supplemented with organic or nano-selenium. One hundred forty-four broilers (starting at 5 days old) were fed with (i) control group: birds received a standard diet; (ii) nano-selenium group: birds were fed with basal diet supplemented with nano-selenium at 0.3 mg/kg; and (iii) organic selenium group: birds received basal diet supplemented with organic selenium at 0.3 mg/kg. We assessed growth performance, carcass characteristics, antioxidant variables, blood parameters, and small intestine morphology. Although Se supplementation did not affect growth performance, carcass traits, and organ weight (P > 0.05), the right to total ventricular weight ratio (RV:TV), malondialdehyde concentration in the liver, and heterophil to lymphocyte ratio were significantly lower in the nano-selenium group relative to the control (P < 0.05). Chickens that received nano-selenium also elicited significantly higher antibody titers after 24 h of an injection of sheep red blood cells (P < 0.05). Nano-selenium supplementation also significantly increased villus height, absorptive surface area, and lamina propria thickness relative to the control (P < 0.05) in different segments of the small intestine. In contrast, organic selenium supplement improved intestinal morphometry only in the jejunum. We conclude that dietary supplementation of 0.30 mg/kg nano-selenium could prevent right ventricular hypertrophy as reflected by reduced RV:TV, reduced levels of lipid peroxidation in the liver, and improved gut function.     

Genetic Analysis of the Latent Period of Stripe Rust in Wheat Seedlings

Genetics of slow‐rusting resistance to yellow rust (Puccinia striiformis f.sp. tritici) was studied by a half‐diallel design using six wheat varieties, Tiritea (susceptible), Tancred, Kotare, Otane, Karamu, and Briscard. The parents and 15 F₁ progenies were evaluated in the greenhouse by three pathotypes 7E18A^?, 38E0A⁺, and 134E134A⁺. The latent period was measured as the number of days from inoculation to the appearance of the first pustule. For each pathotype a randomized complete block design was used and data were analysed by methods of Griffing and Hayman. The range of average degree of dominance was from complete dominance to over‐dominance. Positive and negative degrees of dominance were observed for each pathotype that showed the reversal of dominance. Analysis of variance showed the importance of both additive and dominance effects in controlling the latent period. Broad‐sense heritabilities were 0.99 and narrow‐sense heritabilities ranged from 0.85 to 0.94. Briscard and Karamu for the pathotypes 38E0A⁺ and 134E134A⁺, Kotare for the pathotype 7E18A^? and Tancred for the pathotype 38E0A⁺ had significant and positive general combining ability (GCA) (more resistance) for latent period. The crosses of Kotare with Tancred, Briscard and Karamu indicated the highest and positive specific combining ability (SCA) for the pathotype 7E18A^?. Significant additive genetic component and moderate narrow‐sense heritability indicate the possibility of improving for longer latent period of stripe rust in breeding programmes.     

Infection of Human B Lymphocytes with Lymphocryptoviruses Related to Epstein-Barr Virus

Lymphocryptoviruses (LCVs) naturally infecting Old World nonhuman primates are closely related to the human LCV, Epstein-Barr virus (EBV), and share similar genome organization and sequences, biologic properties, epidemiology, and pathogenesis. LCVs can efficiently immortalize B lymphocytes from the autologous species, but the ability of a given LCV to immortalize B cells from other Old World primate species is variable. We found that LCV from rhesus monkeys did not immortalize human B cells, and EBV did not immortalize rhesus monkey B cells. In this study, baboon LCV could not immortalize human peripheral blood B cells but could readily immortalize rhesus monkey B cells. Thus, efficient LCV-induced B-cell immortalization across distant Old World primate species appears to be restricted by a species-specific block. To further characterize this species restriction, we first cloned the rhesus monkey LCV major membrane glycoprotein and discovered that the binding epitope for the EBV receptor, CD21, was highly conserved. Stable infections of human B cells with recombinant amplicons packaged in rhesus monkey or baboon LCV envelopes were also consistent with a species-restricted block occurring after virus binding and penetration. Transient infections of human B cells with simian LCV resulted in latent LCV EBNA-2 gene expression and activation of cell CD23 gene expression. EBV-immortalized human B cells could be coinfected with baboon LCV, and the simian virus persisted and replicated in human B cells. Thus, several lines of evidence indicate that the species restriction for efficient LCV-induced B-cell immortalization occurs beyond virus binding and penetration. This has important implications for the study of LCV infection in Old World primate models and for human xenotransplantation where simian LCVs may be inadvertently introduced into humans.     

High-pressure hydrocephalus: a novel analytical modeling approach

Hydrocephalus is an abnormal accumulation of cerebrospinal fluid (CSF) within ventricles and subarachnoid space (SAS) as a result of disturbances in secretion or absorption procedures. It is believed that arachnoid villi cells, which are microscopic projections of pia-arachnoid mater that extend into venous channels in sagittal sinus, are the main sites for CSF absorption, but it is tempting to speculate that a significant portion of CSF is removed from the SAS by nasal lymphatic vessels around olfactory nerve. Thus, in this paper, we propose an analytical model of CSF-lymphatic-blood circulation, in which these two output pathways for CSF absorption have been considered. Mathematical relations governing the pressures in different interacting compartments of the brain are considered. In addition, for increasing the similarity of our model to the physiological conditions, the bulk flow mechanism, which is supposed to occur during CSF absorption, has been considered in our model. We used our model to simulate hydrocephalus. The results indicate that the lymphatic disorders have more considerable effect in decreasing CSF absorption, compared to the disturbances in arachnoid villi cells. Based on our modeling, we believe that disorders in lymphatic pathway may be a cause of high-pressure hydrocephalus. Surely experimental studies are required to validate our hypothesis.     

Do high-mobility group box 1 gene polymorphisms affect the incidence of differentiation syndrome in acute promyelocytic leukemia?

Molecular Biology Reports - Differentiation syndrome (DS) is an inflammatory complication seen in some patients with acute promyelocytic leukemia (APL) undergoing differentiation therapy with...