Production and in vivo biologic actions of recombinant mouse interferon alpha 2

We have expressed a recombinant mouse interferon alpha (r.Mu-IFN alpha 2) in Escherichia coli under the control of a tryptophan promoter using a synthetic adaptor formed by annealing two partially complementary oligonucleotides which introduced an ATG start codon and re-established the complete coding sequence of the mature IFN alpha 2 protein in the expression vector. Levels of up to 10(7) reference units of Mu-IFN alpha 2 per liter of culture were obtained using this construction. This recombinant mouse interferon alpha 2 exhibited antiviral activity in mice infected with EMC virus and antitumor activity in mice inoculated with Friend leukemia cells in a manner similar to that of natural mouse interferon alpha/beta.     

Peripheral neurogenic mechanisms in deoxycorticosterone acetate--salt hypertension in the rat

The finding of elevated circulating catecholamine levels in experimental and human hypertension suggests an active sympathoadrenal participation in the pathogenesis of hypertension. In deoxycorticosterone acetate (DOCA)-salt hypertensive rats and in spontaneously hypertensive rats (SHR) the sympathoadrenal reactivity was found to be potentiated in response to various stimuli suggesting alterations in baroreflex functions or in local modulatory mechanisms. Several studies have suggested an attenuation of the alpha 2-presynaptic or local inhibitory mechanism and a potentiation of the beta 2-facilitatory presynaptic mechanism in the peripheral sympathetic system, thus possibly explaining the potentiated sympathoadrenal reactivity in those hypertensive animals. At postsynaptic adrenergic sites, beta-adrenoceptor numbers were reported to be decreased, whereas alpha 1-adrenoceptor numbers were unchanged in the cardiovascular system of DOCA hypertensive rats, thus favoring a dominance of alpha 1-postsynaptic responses in those animals. In support of this concept, the production of inositol monophosphate, used as an index of inositol triphosphate production, was found to be markedly enhanced following norepinephrine-induced alpha 1-stimulation in atria and ventricles as well as in mesenteric and femoral arteries of DOCA-salt hypertensive rats thus suggesting an increased reactivity of the second messenger system linked to alpha 1-adrenoceptors. Since similar abnormalities were also observed in SHR and in human hypertension, it thus appears that an imbalance between alpha- and beta-postsynaptic receptors may exist in various forms of hypertension. These studies therefore suggest the existence of multiple abnormalities in pre- and post-synaptic adrenergic mechanisms in experimental and human hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)     

Growth dynamics of Potamogeton pectinatus L. in Lake Burullus,Egypt: a modelling approach

In this study, we used a macrophyte model to describe the growth production and the interaction between above‐ and below‐ground organs of Potamogeton pectinatus in Lake Burullus, Egypt. Above‐ and below‐ground biomass of P. pectinatus was sampled on a monthly basis from April to December 2011 at three sites of Lake Burullus. Shoots started to grow in April, reached the maximum biomass in September and then rapidly decreased in October when they moved into the senescence stage. Tubers biomass reduced in August due to the upward translocation to shoots, but sharply increased to the maximum in October by downward translocation from shoots and roots. Potamogeton pectinatus allocated approximately 82.3% of its total biomass to shoots, 15.5% to tubers and 2.2% to roots.     

Efficacy of single versus multiple exposure by electromagnetic modalities on gram-negative and positive bacterial strains in an in-vitro model

ObjectivesThe primary purpose of the recent experiment was to scrutinize the dissimilarity between single and multiple exposures by electrotherapeutic modalities to determine the development of Gram-positive and Gram negative bacteria spectrum.Material and methodsBacterial strains employed in this study were Gram-negative bacteria such as Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumonae and Gram-positive bacteria such as Staphylococcus aureus, Staphylococcus saprophyticus and Streptococcus pyogenes. Fluence for Low level laser therapy (LLLT) (810 nm) was 40 J/cm² for 80 s, for microwave (MWD) a dosage of 100-Watt with duration of 5 min and for magnetic field therapy (MT) duration of 30 min with 100% intensity was used.ResultsRepeated Measures of analysis of variances (RANOVA) for within-subject effects was used to detect a global significant change within the means at dissimilar time points. The experiments of within-subjects revealed a significant difference within groups, df of (3, 40), F value of 39.38 and a p value less than 0.001, representing a significant variation between the three groups between pre and post exposures. There was a significant variation between single exposure and multiple exposures in the experimental sample’s pre-post between the four groups with df (1, 40) f value of 2943.69 and p value less than 0.001. Scanning and Transmission electron microscopy images were also taken into account to determine the extent of damage caused to the bacterial cells surface topography in Gram negative and Gram positive spectrums.ConclusionThe study demonstrated that single high exposure with the LLLT appears to have the most emphatic effect followed by exposure by MWD and MT.     

High-dose diethylstilbestrol diphosphate therapy of prostatic cancer after failure of standard doses of estrogens

Ten patients with metastatic prostatic cancer no longer responsive to conventional doses of estrogens (stilbestrol 15 mg. daily or equivalent) were treated with high doses of diethylstilbestrol diphosphate. Objective responses lasting from three to fifteen months were obtained in four patients; three of the patients had previously shown progressive disease following orchidectomy.Toxic manifestations consisted mainly of increased gynecomastia and water retention. No serious cardiovascular complications were encountered. This dose-response effect of estrogens indicates the persistence of hormone-dependent tumours in some patients with recurrent disease despite conventional estrogen therapy.     

Heat stress interferes with formation of double-strand breaks and homolog synapsis

Meiotic recombination (MR) drives novel combinations of alleles and contributes to genomic diversity in eukaryotes. In this study, we showed that heat stress (36°C–38°C) over the fertile threshold fully abolished crossover formation in Arabidopsis (Arabidopsis thaliana). Cytological and genetic studies in wild-type plants and syn1 and rad51 mutants suggested that heat stress reduces generation of SPO11-dependent double-strand breaks (DSBs). In support, the abundance of recombinase DMC1, which is required for MR-specific DSB repair, was significantly reduced under heat stress. In addition, high temperatures induced disassembly and/or instability of the ASY4- but not the SYN1-mediated chromosome axis. At the same time, the ASY1-associated lateral element of the synaptonemal complex (SC) was partially affected, while the ZYP1-dependent central element of SC was disrupted, indicating that heat stress impairs SC formation. Moreover, expression of genes involved in DSB formation; e.g. SPO11-1, PRD1, 2, and 3 was not impacted; however, recombinase RAD51 and chromosome axis factors ASY3 and ASY4 were significantly downregulated under heat stress. Taken together, these findings revealed that heat stress inhibits MR via compromised DSB formation and homolog synapsis, which are possible downstream effects of the impacted chromosome axis. Our study thus provides evidence shedding light on how increasing environmental temperature influences MR in Arabidopsis.

Heat stress inhibits CO formation by affecting SPO11-dependent DSB formation and synapsis of homologous chromosomes, probably through its impact on chromosome axis.