Development,consumption rates and reproductive biology of <Emphasis Type="Italic">Orius albidipennis</Emphasis> reared on various prey

The predatory bug Orius albidipennis (Reuter) (Hemiptera: Anthocoridae) has tremendous potential as a biological control agent, especially in its native range around the Mediterranean Basin and East Africa. The need to exploit native biological control agents is growing in importance as concerns over the introduction of non-native species continue to increase. However, little is known of the effects of different prey on development and reproduction of O. albidipennis compared with other species of Orius. Therefore, we compared the development, survival, reproductive biology, and prey consumption of O. albidipennis when fed eggs of Ephestia kuehniella Zeller, Tetranychus urticae Koch, and Trialeurodes vaporariorum (Westwood), and larvae of Gynaikothrips ficorum (Marchal), under laboratory of 26 ± 1°C, 60 ± 10% RH and 16L:8D photoperiod. Individuals were reared from the neonate stage until death on one of the four prey types. The type of prey had profound effects on all measured performance traits. The highest survival rate was recorded for nymphs that were fed on E. kuehniella eggs, while the lowest survival rate was observed for those fed on T. vaporariorum eggs. The shortest nymphal period was recorded for nymphs fed on E. kuehniella eggs, while the longest was measured for those fed on T. urticae eggs. During the nymphal period, O. albidipennis consumed significantly more eggs of T. urticae than other prey types, whereas the lowest number of consumed prey were eggs of E. kuehniella. Adult females and males consumed significantly more T. urticae eggs than other types of prey. However, Orius albidipennis females showed the highest fecundity when fed on E. kuehniella eggs, and the lowest when fed on T. vaporariorum eggs. Adult females and males that fed on G. ficorum larvae had significantly longer life spans compared with those fed other prey. Because of their relatively rapid development and high fecundity, O. albidipennis fed E. kuehniella eggs had a significantly higher net reproductive rate (R_o) and intrinsic rate of increase (r _m ) than O. albidipennis fed other prey types. Overall, eggs of E. kuehniella were the most suitable diet for nymphs and adults of O. albidipennis. Although less suitable, O. albidipennis could survive and reproduce on the other prey types, which is a favourable attribute in biological control agents. These results on the effect of different prey types on development and reproduction of O. albidipennis will also contribute to the development of mass rearing programs for biological control agents in developing countries, such as Egypt.     

Age-independent,gray matter-localized,brain-enhanced oxidative stress in male fischer 344 rats: brain levels of F(2)-isoprostanes and F(4)-neuroprostanes

While studies showed that aging is accompanied by increased exposure of the brain to oxidative stress, others have not detected any age-correlated differences in levels of markers of oxidative stress. Use of conventional markers of oxidative damage in vivo, which may be formed ex vivo and/or eliminated by endogenous metabolism, may explain these conflicting results. Recently, F₂-isoprostanes and F₄-neuroprostanes, peroxidation products of arachidonic acid and docosahexaenoic acid, respectively, have been identified as sensitive and reliable markers of oxidative injury. Therefore, this study was designed to quantify brain levels of F₂-isoprostanes and F₄-neuroprostanes and their precursors in 4, 10, 50, and 100 week old male Fischer 344 rats. Data show that levels of F₂-isoprostanes and F₄-neuroprostanes were comparable in all animal age groups. However, levels of F₄-neuroprostanes were approximately 20-fold higher than those of F₂-isoprostanes in all age groups, despite the fact that brain levels of docosahexaenoic acid were only twice as high as those of arachidonic acid. Based on our findings, it is concluded that aging is not accompanied by enhanced brain susceptibility to oxidative stress. Furthermore, the metabolically active gray matter of the brain, where docosahexaenoic acid is abundant, appears more susceptible to oxidative stress than the white matter.     

Stages in development of<Emphasis Type="Italic"> Selaginella diffusa</Emphasis> megaspores

In mature megaspores of Selaginella diffusa (C. Presl) Spring the units of the exospore are ordered and become unordered toward the outer and inner surfaces. The exospore surface is coated with silica at maturity. The insertion of the future gap begins in early stages with formation of many minigaps within the inner part of the exospore distally. The mesospore, like the exospore, is resistant to the acetolysis reaction and can, thus, provisionally be considered to consist of sporopollenin. Unit structures within the outer part of the mesospore are unordered, but become ordered in the middle and inner parts. The inner surface of the mesospore appears verrucate. In maturing megaspores, the mesospore is mostly disintegrated and the inner exospore, which encapsulated the mesospore, remains as a somewhat isolated structure, and is again near the outer exospore. There are connecting strands across the gap between the inner surface of the outer exospore and the surface of the inner exospore. There are also spheres on the outer surface of the inner exospore. Electronic Publication     

Protective effect of arabic gum against cardiotoxicity induced by doxorubicin in mice: a possible mechanism of protection

Arabic gum (AG) is a naturally occurring compound that has been proposed to possess potent antioxidant activity. In this study, the possible effects whereby AG could protect against cardiotoxicity induced by doxorubicin (DOX) in mice were carried out. Administration of single dose of DOX (15 mg/kg, i.p.) induced cardiotoxicity 72 h, manifested biochemically by a significant elevation of serum creatine kinase (CK) (EC 2.7.3.2). In addition, cardiotoxicity was further confirmed by the significant increase in lipid peroxides measured as malondialdehyde (MDA). Administration of AG (25 g/kg) orally for 5 days before and 72 h after DOX injection produced a significant protection against cardiotoxicity induced by DOX. This was evidenced by significant reductions in serum CK and cardiac lipid peroxides. The effect of AG was examined on the superoxide anion radical generated by enzymatic and nonenzymatic methods. The results indicate that AG is a potent superoxide scavenger. The superoxide scavenging effect of AG may explain, at least in part, the protective effect of AG against cardiotoxicity induced by DOX.     

Material properties of the human calcaneal fat pad in compression: experiment and theory

The structural behaviour of the human heel pad has been studied extensively due to its ability to absorb shock, protect against excessive local stress, and reduce plantar pressures. However, the material properties of the tissue have not been adequately measured. These must be known in order to perform a finite element analysis of the effect of factors such as foot geometry and shoe/surface construction on heel pad function. Therefore, the purposes of this study were to (a) measure the viscoelastic behaviour of the fat pad in compression, and (b) to determine an appropriate constitutive equation to model the tissue. A series of unconfined compression tests were performed on 8 mm diameter cylinders of fat pad tissue, consisting of quasi-static, 175, 350 mm/s and stress-relaxation tests to 50% deformation. The tissue exhibited nonlinear, viscoelastic behaviour. No significant difference was found in the quasi-static behaviour between samples from different locations and orientations in the heel. The stress-relaxation tests were used to determine the time constant (τ₁=0.5 s), the 175 mm/s test to determine the relaxation coefficient (g₁=28), and the 350 mm/s compression test to determine the material constants (C₁₀₀=C₀₁₀=0.01, C₂₀₀=C₀₂₀=0.1 Pa) of a single-phase, hyperelastic, linear viscoelastic strain energy function (r²=0.98).     

Variation of Giemsa C-band and fluorochrome banded karyotypes,and relationships inAllium subgen.Molium

The somatic karyotypes of 10 taxa belonging toAllium subgen.Molium (Liliaceae) from the Mediterranean area have been investigated using Giemsa C-band and fluorochrome (Hoechst, Quinacrine) banding techniques. A wide range of banding patterns has been revealed. InAllium moly (2n = 14),A. oreophilum (2n = 16) andA. paradoxum (2n = 16) C-banding is restricted to a region on each side of the nucleolar organisers and the satellites show reduced fluorescence with fluorochromes. The satellites are also C-banded and with reduced fluorescence inA. triquetrum (2n = 18), but two other chromosome pairs also have telomeric bands which are not distinguished by fluorochrome treatment. InA. erdelii (2n = 16) 4 pairs of metacentric chromosomes have telomeric C-bands while 2 pairs of telocentric chromosomes have centromeric C-banding. InA. subhirsutum (2n = 14),A. neapolitanum (2n = 28),A. trifoliatum subsp.hirsutum (2n = 14) andA. trifoliatum subsp.trifoliatum (2n = 21) chromosomes with long centromeres, consisting of a centromere and nucleolar organiser are positively C-banded on each side of the constriction. InA. subhirsutum banding is confined to the pair of chromosomes with this feature, whereas inA. neapolitanum one additional chromosome pair has telomeric bands and inA. trifoliatum there are varying numbers of chromosomes with centromeric and telomeric bands, depending on the subspecies.A. zebdanense (2n = 18) shows no C-bands. The banding patterns in this subgenus are compared with those recorded for otherAllium species and with the sectional divisions in the genus. Evidence from the banding patterns for allopolyploidy inA. trifoliatum subsp.trifoliatum andA. neapolitanum is discussed.     

Analysis of Binding Interaction Between Antibacterial Ciprofloxacin and Human Serum Albumin by Spectroscopic Techniques

To develop an efficient method for extracting and purifying the active ingredient, arctiin, from Fructus arctii and to investigate the protective effect of arctiin against glucose-induced rat aortic endothelial cell (RAEC) injury was investigated. Using a L9 (34) orthogonal array and two-step column chromatography (with AB-8 macroporous resin) arctiin extraction was optimized using a reflux method with 70 % ethanol. The RAECs were then treated with different concentrations of arctiin (1, 10, or 100 μg/ml). The effects of arctiin on cell viability in a high glucose medium, malondialdehyde (MDA) levels, and lactate dehydrogenase were measured using commercially available assays. After extraction, the purity of arctiin reached 95.7 %. In rats, arctiin was shown to stimulate the proliferation of RAECs in a high glucose medium in a dose-dependent manner. Exposure of RAECs to high glucose resulted in a significant increase in MDA and release of lactate dehydrogenase. This was accompanied by significant increase in nitric oxide release and expression of antiendothelial nitric oxide synthase. This technique resulted in relatively pure arctiin extraction. Furthermore, the results from this study suggest that arctiin could potentially function as a protector against vascular endothelial cell injury and further investigation is warranted.     

Beta 3 adrenergic receptor Trp64Arg polymorphism and manifestation of coronary artery disease in Arabs

The substitution of tryptophan (Trp) by arginine (Arg) at position 64 in the beta3-adrenoceptor (beta3-AR) gene has been associated with obesity, diabetes mellitus, and coronary artery disease (CAD). We have investigated whether the Trp64Arg polymorphism is associated with the manifestation of CAD or one of its important risk factors, such as obesity, diabetes mellitus, elevated cholesterol and triglyceride levels, or hypertension in the Arab population. All participating subjects were genotyped for this polymorphism using the polymerase chain reaction followed by enzymatic digestion and sequencing. In the angiographed normal control subjects (n=495), 90.3% were homozygous Trp/Trp, 9.5% were heterozygous Trp/Arg, and 0.2% were homozygous for the Arg/Arg genotype, compared to 87%, 12.3%, and 0.7%, respectively, among angiographically confirmed CAD patients (n=981). There was no statistical difference in the distribution of genotypes or allele frequencies between the CAD and control groups. We carried out a stepwise logistic regression analysis to study the possible combined effect of the genotypes and other risk factors on CAD. All variables were retained in the model, with p values of 0.014, 0.006, 0.005, < 0.001, 0.045, 0.002, < 0.001, and 0.016 for genotype, diabetes mellitus, sex, family history of CAD, obesity, myocardial infarction, smoking, and age, respectively. In conclusion, the Trp64Arg polymorphism of the beta3-AR gene does not represent an independent risk factor for CAD in Arabs. However, in the presence of other CAD risk factors, this polymorphism may be used as a predictor of CAD.     

An efficient targeted radiotherapy/gene therapy strategy utilising human telomerase promoters and radioastatine and harnessing radiation-mediated bystander effects

BACKGROUND: Targeted radiotherapy achieves malignant cell-specific concentration of radiation dosage by tumour-affinic molecules conjugated to radioactive atoms. Combining gene therapy with targeted radiotherapy is attractive because the associated cross-fire irradiation of the latter induces biological bystander effects upon neighbouring cells overcoming low gene transfer efficiency. METHODS: We sought to maximise the tumour specificity and efficacy of noradrenaline transporter (NAT) gene transfer combined with treatment using the radiopharmaceutical meta-[(131)I]iodobenzylguanidine ([(131)I]MIBG). Cell-kill was achieved by treatment with the beta-decay particle emitter [(131)I]MIBG or the alpha-particle emitter [(211)At]MABG. We utilised our novel transfected mosaic spheroid model (TMS) to determine whether this treatment strategy could result in sterilisation of spheroids containing only a small proportion of NAT-expressing cells. RESULTS: The concentrations of [(131)I]MIBG and [(211)At]MABG required to reduce to 0.1% the survival of clonogens derived from the TMS composed of 100% of NAT gene-transfected cells were 1.5 and 0.004 MBq/ml (RSV promoter), 8.5 and 0.0075 MBq/ml (hTR promoter), and 9.0 and 0.008 MBq/ml (hTERT promoter), respectively. The concentrations of radiopharmaceutical required to reduce to 0.1% the survival of clonogens derived from 5% RSV/NAT and 5% hTERT/NAT TMS were 14 and 23 MBq/ml, respectively, for treatment with [(131)I]MIBG and 0.018 and 0.028 MBq/ml, respectively, for treatment with [(211)At]MABG. CONCLUSIONS: These results indicate that the telomerase promoters have the capacity to drive the expression of the NAT. The potency of [(211)At]MABG is approximately three orders of magnitude greater than that of [(131)I]MIBG. Spheroids composed of only 5% of cells expressing NAT under the control of the RSV or hTERT promoter were sterilised by radiopharmaceutical treatment. This observation is indicative of bystander cell-kill.