Aspartic Proteinase Members Secreted by the Ruminant Placenta: Specificity of Three Radioimmunoassay Systems for the Measurement of Pregnancy-associated Glycoproteins

Pregnancy‐associated glycoproteins (PAGs) isolated from the placenta of various ruminant species are enzymatically inactive members of the aspartic proteinase family. The measurement of these proteins in the maternal blood can be a good indicator of the presence of a live embryo. As certain aspartic proteinases are present in biological fluids in physiological and pathological conditions at various concentrations, it was necessary to determine the specificity of three radioimmunoassay (RIA) systems currently used for the detection of PAG molecules. Commercially available members of the aspartic proteinase family like pepsinogen, pepsin, chymosin, rennet, cathepsin D and renin were tested in a wide concentration range (10 ng/ml – 1 mg/ml). Pepsinogen cross‐reacted in RIA 1, RIA 2 and RIA 3 over 1 mg/ml, 50 μg/ml and 500 μg/ml concentrations, respectively. In the presence of pepsin, cross‐reaction was observed in RIA 1, RIA 2 and RIA 3 over 1 mg/ml, 500 μg/ml and 1 mg/ml concentrations, respectively. Chymosin and rennet could cross‐react in RIA 2 and RIA 3, while renin and cathepsin D did not decrease the binding of the tracer to antisera more, than that of the minimal detection limit. As the plasma/serum concentrations of the examined aspartic proteinases reported in the literature were outside the concentration range where cross‐reaction was observed, it can be concluded that these RIA systems were specific for the detection of PAGs in biological fluids.     

Microfabrication techniques for integrated sensors and microsystems

Integrated sensors and actuators are rapidly evolving to provide an important link between very large scale integrated circuits and nonelectronic monitoring and control applications ranging from biomedicine to automated manufacturing. As they continue to expand, entire microsystems merging electrical, mechanical, thermal, optical, magnetic, and perhaps chemical components should be possible on a common substrate.     

Zinc sorption–desorption by sand,silt and clay fractions in calcareous soils of Iran

Zinc sorption–desorption by sand, silt and clay fractions of six representative calcareous soils of Iran were measured. Sand, silt and clay particles were fractionated after dispersion of soils with an ultrasonic probe. Zinc sorption analysis was performed by adding eight rates of Zn from 6 to 120 μmol g^?1. For the desorption experiment, samples retained after the measurement of Zn sorption were resuspended sequentially in 0.01 M NaNO₃ solution and shaken for 24 h. Results indicated that Zn sorption by soil fractions increased in the order clay > silt > sand, and correlated negatively with CaCO₃ content and positively with cation exchange capacity (CEC) and smectite content. Results indicated that for all fractions, the Langmuir equation described the sorption rates fairly well. In contrast to sorption, Zn desorption from soil fractions increased in the order sand > silt > clay, and correlated positively with CaCO₃ content, CEC and smectite content. Results showed that parabolic diffusion and two constant equations adequately described the reaction rates of Zn desorption. In general, for all soils studied, the coarser the particle size, the less Zn sorption and more Zn desorption, and this reflects much higher risk of Zn leaching into groundwater or plant uptake in contaminated soils.     

Factors Affecting Plasma Pregnancy-associated Glycoprotein 1 Concentrations Throughout Gestation in High-producing Dairy Cows

This study was designed to establish the factors, if any, which could affect plasma pregnancy-associated glycoprotein-1 (PAG-1) expression in a study population of 87 pregnant, high-producing dairy cows. The factors examined were: semen providing breed (Holstein-Friesian vs Limousin), outcome of gestation (male vs female newborn, and singleton vs twin pregnancies), lactation number, milk production at pregnancy diagnosis, plasma progesterone concentration, season of gestation (warm period, March–November vs cool period, December–February), and day of gestation (40, 90, 120, 150, 180 and 210). Pregnancy was diagnosed by transrectal ultrasound on day 40 post-insemination and by palpation per rectum on days 90, 120, 150, 180 and 210. Blood samples were collected from each animal immediately before each pregnancy diagnosis. The relative contributions of the different factors on PAG-1 concentrations were evaluated by GLM repeated measures analysis of variance. No significant effects of the herd, foetal sex, milk production, lactation number and plasma progesterone concentrations were observed. In contrast, twin pregnancy, the use of Limousin semen and conception during the cool period were correlated with significantly increased plasma PAG-1 concentrations throughout gestation. Our data indicate that both cow well-being during early placental development, determined in our conditions by reduced heat stress when conception occurred in the cool season, and crossbreed pregnancies lead to improved PAG-1 production throughout the gestation period.     

Stimulation in the movement and uptake of phosphorus in response to magnetic P solution and arbuscular mycorrhizal fungi in Ocimum basilicum

A greenhouse experiment was conducted to assess the effects of magnetic field, arbuscular mycorrhizal fungi (AMF), and phosphorus (P) concentration in the nutrient solution (0, 5, 10, 20, or 40 mg L^?1) on the mobility and accumulation of P in soil and plant tissues of basil (Ocimum basilicum L.). The experiment was designed as a factorial combination and treatments were arranged in a completely randomized design with four replicates. Magnetic field increased water-soluble P in the soil and P concentration in plant shoot by 30.0% and 13.0%, respectively, in comparison to the control. The application of magnetic field and inoculation of AMF at 10 mg P L^?1 increased the P translocation efficiency by 23.3% and 17.8%, respectively. Overall, our results demonstrated that the use of magnetic field and AMF could be an effective tool for enhancing of uptake and movement efficiency of P even at low concentrations.     

The Magnetic Susceptibility and Iron Oxides of Aquic Soils in Southern Iran

An investigation of the effect of aquic conditions on Fe-oxides distribution and magnetic susceptibility (χ_lf) was conducted on selected soils from Southern Iran. Seven pairs of adjacent soil pedons with different soil moisture regimes (aquic and non-aquic), were selected. The average concentrations of poorly crystalline Fe (Fe_o) and total free Fe (Fe_d) in aquic soils were 0.2 and 0.07% respectively, and 0.45 and 0.9% in non-aquic soils, respectively. The ratio of Fe_o/Fe_d varied from 0.03 to 0.64. χ_lf ranged from 1.8 to 113 × 10^?8 m³ kg^?1 in the soil studied. The variation of χ_fd ranged from 0.0 to 9.65%. The χ_fd values observed in non-aquic soils were larger than in aquic soils (4.00% vs. 1.37%). Positive correlations were observed between χ and clay contents in both aquic and non-aquic soils; however, non-aquic soil samples showed a larger coefficient of determination. A positive correlation existed between χ_fd and χ in aquic and non-aquic soils. Higher values of χ_fd were observed at the soil surface of non-aquic soil samples than at deeper levels, suggesting a greater proportion of ultrafine grains. Of the soil properties that were assessed, clay, cation exchangeable capacity (CEC), Fe_d, Fe_o/Fe_d ratio, χ_lf and χ_fd contents, changed significantly in response to the aquic condition.     

Monitoring of the fermentation media of citric acid by the trimethylsilyl derivatives of the organic acids formed

In this approach, a derivatization method is described for monitoring of organic acids in fermentation media without any separation step. The aqueous phase of fermentation media was evaporated and heated in a silylation reagent to form trimethylsilyl (TMS) derivatives. The silylated compounds are analyzed by 29Si nuclear magnetic resonance (29Si NMR) and gas chromatography-mass spectrometry (GC-MS). 29Si NMR can qualitatively monitor the components produced in the Krebs cycle. Quantification of these compounds is investigated by using selected ion monitoring mode of mass spectrometry. In this mode, mass to charge (m/z) values of their [M - 15]+ ions, which are 465, 275, 247, 221, 335, 251, and 313 of TMS derivatives of citric, alpha-ketoglutaric, succinic, fumaric, l-malic, oxaloacetic, and palmitic (as an internal standard), acids, respectively, are used. The limit of detection and the linear working range for derivatized citric acid were found to be 0.1 mg L(-1) and 10-3 x 10(4) mg L(-1). The relative standard deviation of the method for five replicates was 2.1%. The average recovery efficiency for citric acid added to culture media was approximately 97.2%. Quantitative results of GC-MS are compared with those obtained by an ultraviolet-visible method.     

Clinical and Para‐clinical Findings of a Recent Outbreaks of Peste des Petits Ruminants in Iran

Peste des petits ruminants (PPR) is a highly contagious and infectious viral disease of domestic and wild small ruminants characterized by fever, erosive stomatitis, conjunctivitis, gastroenteritis and pneumonia. Goats are usually more severely affected than sheep. Peste des petits ruminants is caused by a paramyxovirus of the Morbillivirus genus. In March 2004, a flock of sheep in Tehran province with 430 deaths was visited. According to the history taken from the owner, at disease onset most of the deaths were recorded from adult sheep, 3 weeks later lambs (2 weeks to 4 months of age) showed the highest death rate. All animals from 3 months age received rinderpest vaccine 1 month after onset. Many of the lambs died just a few hours after their first sucking of the colostrum from infected mothers. Most of them showed very acute form of disease and died a few hours after onset of clinical signs. In clinical examinations most of the cases showed severe depression, high fever (41°C), anorexia, mocopulurent nasal discharge, erosive and necrotic stomatitis (dental path, hard palate and cheeks), diarrhoea and dehydration. Para‐clinical findings including histopathological, serological and haematological examinations also confirmed the presence of PPR in this flock. PPR outbreaks have been frequent in Iran in recent years. Further, we suggest that PPR is not a recent invader of Iran. The main difference in clinical signs between this outbreak and the same in other reports is that goats did not show any obvious signs of PPR. This might be due to the number of the goats (>1% of the flock) and keeping them separate from the sheep. The present article reviews the details of this outbreak in Iran.