Complete template-directed enzymatic synthesis of a potential antisense DNA containing 42 methylphosphonodiester bonds

P-Methyl thymidine triphosphate was prepared through the pyrophosphorolysis of P -methyl thymidine diphosphate P^β-diphenyl ester and tested as an alternative substrate for E. coli DNA polymerase 1 (Klenow fragment) using several template-primer systems requiring the formation of 1 to 42 methylphosphono diester bonds. The enzyme catalyzes the incorporation of a P-methyl thymidylic residue with (Sp)-configuration at a single site in a recessive 3′-end as well as at multiple sites along a growing 167 nucleotide long chain. The synthesis of a full length product, containing 42 sites of methylphosphonate incorporation was observed.     

Ability of female ixodid ticks to recover from poisoning with DDT in the process of feeding]

Ability of hungary females of Ixodes persulcatus, Haemaphysalis concinna and Dermacentor silvarum to feed and lay eggs after having been exposed to different DDT doses (LD100) has been studied. The ticks heavily injuried but still mobile can feed on the host and lay eggs, i.e. to overcome the poisoning. Clutches laid by these females do not differ from control ones. Loss of mobility deprives the ticks of the ability to fed. An increase in DDT dose (LD100 X 100, experiment with I. persulcatus) does not allow the ticks to feed even if the ability to movement is preserved.     

Accelerated leaf senescence takes part in enhanced resistance in cucumber mosaic virus inoculated pepper leaves

Altered photosynthetic reactions in cucumber mosaic virus (CMV) inoculated leaves of virus resistant lines L113 and L57 and susceptible pepper (Capsicum annuum L.) plants cv. Albena grown in controlled environment and in the field were investigated. The CMV inoculated leaves of virus resistant lines developed different symptoms—necrotic local lesions on L113 and chlorotic spots on L57 while the same leaves of susceptible cv. Albena were symptomless. The changes in Photosystem II (PSII) and PSI electron transport were evaluated by chlorophyll fluorescence, and far-red (FR) light induced leaf absorbance A _810–860. CMV infection caused a decrease in maximal PSII quantum yield, F _v/F _m, in susceptible leaves. Increased non-photochemical fluorescence quenching in CMV-inoculated leaves of both resistant lines were observed. In CMV-inoculated leaves of all tested plants FR light induced P700 oxidation was decreased. In the present study, the viral-infected pepper plants grown in controlled environment to avoid the effects of abiotic factors were used as model system that allow us to investigate the differences in leaf senescence in CMV-inoculated leaves of susceptible and resistant pepper lines expressing different symptoms. Earlier leaf falls of inoculated leaves as a result of accelerated leaf senescence is important for building successful secondary virus resistance strategy following fast responses such as hypersensitive reaction.     

Evaluation of Poly(2-Ethyl-2-Oxazoline) Containing Copolymer Networks of Varied Composition as Sustained Metoprolol Tartrate Delivery Systems

Segmented copolymer networks (SCN) based on poly(2-ethyl-2-oxazoline) and containing 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, and/or methyl methacrylate segments have been evaluated as potential sustained release systems of the water soluble cardioselective β-blocker metoprolol tartrate. The structure and properties of the drug carriers were investigated by differential scanning calorimetry, attenuated total reflectance Fourier transform infrared spectroscopy, scanning electron microscopy, and atomic force microscopy. Swelling kinetics of SCNs in various media was followed, and the conditions for effective MT loading were specified. MT-loaded SCNs with drug content up to 80 wt.% were produced. The release kinetics of metoprolol tartrate from the systems was studied and it was shown that the conetworks of different structure and composition are able to sustain the metoprolol tartrate release without additional excipients.     

Liquid chromatography method for simultaneous analysis of amino acids and biogenic amines in biological fluids with simultaneous gradient of pH and acetonitrile

A liquid chromatography method for simultaneous analysis of amino acids, polyamines, catecholeamines and metanephrines in human body fluids after derivatization with 9-fluorenylmethyloxycarbonyl chloride was developed. The chromatographic behavior of analytes at different pH of mobile phase was studied. Successful baseline resolution of all analyzed compounds was achieved using simultaneous gradient of pH and organic modifier in reverse phase mode of HPLC within 36 min. The repeatability of the proposed procedure in respect of retention time and peak area, expressed as RSD, ranges from 0.06 to 1.64% and 0.4 to 7.6%, respectively. The method linearity in the range of 1-200 microM for amino acids and in the range of 0.1-20 microM for polyamines, catecholeamines and metanephrines was found to be with correlation coefficients higher than 0.994. The limit of quantification (LOQ) was assessed to be in the range of 2.6-10 pmol for amino acids and 2-4 pmol for polyamines, catecholeamines and metanephrines.     

Peptide substrate for caspase-3 with 2-aminoacridone as reporting group

Synthesis and properties of a new fluorescent/fluorogenic substrate Ac-DEVD-AMAC for caspase-3 are reported. The substrate is obtained by conventional Fmoc-based solid phase peptide synthesis and its properties are investigated with regard to fluorescence, sensitivity, applicability and kinetic constants. A non-traditional approach to assay the proteases activity using 2-aminoacridone labeled peptides is proposed. This approach utilizes the decrease of fluorescence intensity of a sample as a measure for the enzyme activity.     

In vivo and in vitro investigation of salt tolerance in three anthocyaninless mutants in tomato (Lycopersicon esculentum Mill.)

Growth responses of a tomato cultivar Ailsa Craig and the ah-, aw- and bls-isogenic/near isogenic lines (IL/NIL) from it were evaluated and compared at cotyledons stage under salt treatment in vivo and in vitro experiments. No differences in hypocotyl and root growth responses were detected between the anthocyanin-containing and the anthocyaninless lines within the in vivo experiments. The anthocyaninless mutants, (except in some cases the bls mutant), exhibited higher callogenic and shoot-forming capacity on both, control and salinized media. It was concluded that for this reason it would be difficult to determine the relationship between the in vivo and in vitro responses of the lines studied and as well as to evaluate the usefulness of the in vitro method in testing these lines for salt tolerance.     

Functional male sterility in tomato (Lycopersicon esculentum Mill.) and its application in hybrid seed production

Advantages and disadvantages in using functional male sterility (positional sterile — ps, positional sterile 2 — ps 2, and excerted stigma — ex) in tomato hybrid seed production and attempts to elaborate systems for their more efficacious use in breeding were discussed in this review. It was concluded that the application of one of these types of sterility, (ps 2) in practice, although in a limited number of countries, showed the functional male sterility in tomato was a potential not to be underestimated in developing approaches that aimed at reducting the time and cost associated with hybrid seed production.     

Engineered Mitochondrial Ferritin as a Magnetic Resonance Imaging Reporter in Mouse Olfactory Epithelium

We report the design of a MRI reporter gene with applications to non-invasive molecular imaging. We modified mitochondrial ferritin to localize to the cell cytoplasm. We confirmed the efficient cellular processing of this engineered protein and demonstrated high iron loading in mammalian cells. The reporter’s intracellular localization appears as distinct clusters that deliver robust MRI contrast. We used this new reporter to image in vivo and ex vivo the gene expression in native olfactory sensory neurons in the mouse epithelium. This robust MRI reporter can facilitate the study of the molecular mechanisms of olfaction and to monitor intranasal gene therapy delivery, as well as a wide range of cell tracking and gene expression studies in living subjects.     

Ultrasonic evaluation of uterine involution in Bulgarian Murrah buffalo after administration of oxytocin

The aim of this study was to determine the time taken for complete uterine involution in Bulgarian Murrah buffaloes following normal parturition and oxytocin stimulated milking; and to establish the time course of the change in size of the uterine horns, the cervix and caruncles between parturition and involution by means of ultrasonography. There were 17 animals in the study aged 3-6 years and average parity of 2.17 ± 0.18. They were administered 20 IU oxytocin 15 min before each milking. Rectal palpation and transrectal ultrasonography were performed at 3 d intervals from Days 1 to 34 post partum. The involution of the non-gravid and gravid uterine horns, and the cervix was complete by Days 22 and 25 post partum when their diameters were 2.7 ± 0.4 cm, 2.8 ± 0.3 cm and 3.12 ± 0.4 cm, respectively. Caruncles underwent rapid regression until Day 10 post partum. It was not possible to determine the dimensions of the caruncles after that time. The cumulative percentage of animals whose uterus was located in the pelvic cavity increased from 24% at Day 10 post partum to 100% at Day 34 post partum. The combination of rectal palpation and transrectal ultrasonography provided a reliable method of evaluating changes in the uterus over time and determining the time of uterine involution. The present study showed that complete uterine involution, with the uterus located in the pelvic cavity, was achieved by Day 34 after parturition in all 17 Bulgarian Murrah buffaloes treated with oxytocin before milking.