Age related effects of organochlorine insecticide lindane on intestinal brush border membrane in rats.

The effect of oral administration of lindane (gamma-HCH) has been studied on the intestine in 10-day, 20-day and 100-day old rats. In 10 day-old suckling pups exposed to lindane, there was a significant decrease in the activities of sucrase (29%), lactase (20%) and that of alkaline phosphatase (24%) compared to control. Sialic acid content of the brush borders was significantly decreased (29%) in 10-day old as well as in 20- and 100-day old rats (20 and 25% respectively), while fucose content of the membranes was significantly enhanced in all the age groups upon pesticide treatment. Among the brush border lipids, cholesterol content was significantly increased in all the age groups studied, the maximum increase of 35% being observed in 10-day-old rats. Membrane phospholipids were also increased in 20- and 100-day old animals (22% each) on lindane exposure. The present studies indicated that brush border membranes of suckling rat intestine were more susceptible to pesticide induced changes compared to older animals.     

Long-term stability of marker gene expression in Prunus subhirtella: a model fruit tree species

Transgenic trees currently are being produced by Agrobacterium-mediated transformation and biolistics. Since trees are particularly suited for long-term evaluations of the impact of the technology, Prunus subhirtella autumno rosa (PAR) was chosen as model fruit tree species and transformed with a reporter gene (uidA) under the control of the 35S promoter. Using Southern and GUS fluorometric techniques, we compared transgene copy numbers and observed stability of transgene expression levels in 34 different transgenic plants, grown under in vitro, greenhouse and screenhouse conditions, over a period of 9 years. An influence of grafting on gene expression was not observed. No silenced transgenic plant was detected. Overall, these results suggest that transgene expression in perennial species, such as fruit trees, remains stable in time and space, over extended periods and in different organs, confirming the value of PAR as model species to study season-dependent regulation in mature stone fruit tissues. While the Agrobacterium-derived Prunus transformants contained one to two copies of the transgenes, 91% of the transgenic events also contained various lengths of the bacterial plasmid backbone, indicating that the Agrobacterium-mediated transformation is not as precise as previously perceived. The implications for public acceptance and future applications are discussed.     

Salmonella induces a switched antibody response without germinal centers that impedes the extracellular spread of infection

T-dependent Ab responses are characterized by parallel extrafollicular plasmablast growth and germinal center (GC) formation. This study identifies that, in mice, the Ab response against Salmonella is novel in its kinetics and its regulation. It demonstrates that viable, attenuated Salmonella induce a massive early T-dependent extrafollicular response, whereas GC formation is delayed until 1 mo after infection. The extrafollicular Ab response with switching to IgG2c, the IgG2a equivalent in C57BL/6 mice, is well established by day 3 and persists through 5 wk. Switching is strongly T dependent, and the outer membrane proteins are shown to be major targets of the early switched IgG2c response, whereas flagellin and LPS are not. GC responses are associated with affinity maturation of IgG2c, and their induction is associated with bacterial burden because GC could be induced earlier by treating with antibiotics. Clearance of these bacteria is not a consequence of high-affinity Ab production, for clearance occurs equally in CD154-deficient mice, which do not develop GC, and wild-type mice. Nevertheless, transferred low- and high-affinity IgG2c and less efficiently IgM were shown to impede Salmonella colonization of splenic macrophages. Furthermore, Ab induced during the infection markedly reduces bacteremia. Thus, although Ab does not prevent the progress of established splenic infection, it can prevent primary infection and impedes secondary hemogenous spread of the disease. These results may explain why attenuated Salmonella-induced B cell responses are protective in secondary, but not primary infections.     

Structural and solution studies of a novel tetranuclear silver(I) cluster of [1,3-di(2-methoxy)benzene]triazene

The synthesis, characterization, crystal structure, ¹H NMR, spectrophotometric and conductometric studies of a new tetranuclear silver(I) complex of [1,3-di(2-methoxy)benzene]triazene are reported. Reaction of the ligand with silver acetate resulted in the formation of a tetranuclear cluster with a four-member Ag-Ag ring core, composed of four triazenide ligands and four metals. The results of studies of the stoichiometry and formation and of complex in tetrahydrofuran solution were found to be in support of its solid state structure.     

Prawn lipocalin: characteristics and expressional pattern in subepidermal adipose tissue during reproductive molting cycle

In crustaceans, the fascinating processes of maturation, reproductive molting and carapace coloration are regulated by hydrophobic molecules. Interestingly, most of the molecules are ligands of lipocalin. To understand the role of lipocalin in the aforementioned processes at molecular level, we isolated a cDNA that belongs to the lipocalin family, from a central nervous system cDNA library of Macrobrachium rosenbergii. We monitored the spatial and temporal distributions of the mRNA by using Northern Blotting analysis. Our results demonstrated that this gene expresses abundantly in the subepidermal adipose tissue, while faintly in the hepatopancreas and central nervous system. However, no signal was detected in other tissues including muscle, gill and ovary. Its expression levels in subepidermal adipose tissue during various stages of maturation as well as through the whole molting cycle showed that prawn lipocalin is involved in sexual maturation, as the maximal level was observed just after molt.     

Follicular waves during the oestrous cycle in Nili-Ravi buffaloes undergoing spontaneous and PGF2alpha-induced luteolysis

The objective of this study was to characterize the follicular waves and associated ovarian events during spontaneous and PGF(2alpha)-induced oestrous cycles in Nili-Ravi buffaloes. In Exp. 1, (n=13 oestrous cycles) follicular and luteal development was monitored by ultrasonography and jugular blood samples were collected simultaneously on alternate days. Of 12 oestrous cycles, 9 (75%) had two waves of follicular activity and only 3 (25%) had three waves. The mean (+/-S.E.M.) length of the oestrous cycle was shorter (P<0.05) in buffaloes with two waves than in those with three waves (21.2+/-0.1 days versus 22.8+/-0.1 days). In Exp. 2, follicular dynamics were compared in buffaloes undergoing spontaneous (n=12 oestrous cycles) and PGF(2alpha)-induced (n=9) regression of the corpus luteum (CL). The dynamics of ovulatory follicular growth during the 3 days before oestrus were similar (P>0.05) in buffaloes undergoing spontaneous and PGF(2alpha)-induced luteolysis. These results show that (1) the majority of buffaloes had a two wave pattern of follicular growth and emergence of a third wave was associated with a longer luteal phase, and (2) follicular dynamics during the 3 days before oestrus were similar in buffaloes undergoing spontaneous and PGF(2alpha)-induced luteolysis.     

A recombinant allosteric lectin antagonist of HIV-1 envelope gp120 interactions

The first, critical stage of HIV-1 infection is fusion of viral and host cellular membranes initiated by a viral envelope glycoprotein gp120. We evaluated the potential to form a chimeric protein entry inhibitor that combines the action of two gp120-targeting molecules, an allosteric peptide inhibitor 12p1 and a higher affinity carbohydrate-binding protein cyanovirin (CVN). In initial mixing experiments, we demonstrated that the inhibitors do not interfere with each other and instead show functional synergy in inhibiting viral cell infection. Based on this, we created a chimera, termed L5, with 12p1 fused to the C-terminal domain of CVN through a linker of five penta-peptide repeats. L5 revealed the same broad specificity as CVN for gp120 from a variety of clades and tropisms. By comparison to CVN, the L5 chimera exhibited substantially increased inhibition of gp120 binding to receptor CD4, coreceptor surrogate mAb 17b and gp120 antibody F105. These binding inhibition effects by the chimera reflected both the high affinity of the CVN domain and the allosteric action of the 12p1 domain. The results open up the possibility to form high potency chimeras, as well as noncovalent mixtures, as leads for HIV-1 envelope antagonism that can overcome potency limits and potential virus mutational resistance for either 12p1 or CVN alone.     

Impact of daily consumption of iron fortified ready-to-eat cereal and pumpkin seed kernels (Cucurbita pepo) on serum iron in adult women

Iron deficiency, anemia, is the most prevalent nutritional problem in the world today. The objective of this study was to consider the effectiveness of consumption of iron fortified ready-to-eat cereal and pumpkin seed kernels as two sources of dietary iron on status of iron nutrition and response of hematological characteristics of women at reproductive ages. Eight healthy female, single or non pregnant subjects, aged 20-37 y consumed 30 g of iron fortified ready-to-eat cereal (providing 7.1 mg iron/day) plus 30 g of pumpkin seed kernels (providing 4.0 mg iron/day) for four weeks. Blood samples collected on the day 20 of menstrual cycles before and after consumption and indices of iron status such as reticulocyte count, hemoglobin (Hb), hematocrit (Ht), serum ferritin, iron, total iron-binding capacity (TIBC), transferrin and transferrin saturation percent were determined. Better response for iron status was observed after consumption period. The statistical analysis showed a significant difference between the pre and post consumption phase for higher serum iron (60 +/- 22 vs. 85 +/- 23 ug/dl), higher transferrin saturation percent (16.8 +/- 8.0 vs. 25.6 +/- 9.0%), and lower TIBC (367 +/- 31 vs. 339 +/- 31 ug/dl). All individuals had higher serum iron after consumption. A significant positive correlation (r=0.981, p=0.000) between the differences in serum iron levels and differences in transferrin saturation percentages and a significant negative correlation (r=-0.916, p<0.001) between the differences in serum iron levels and differences in TIBC was found, as well. Fortified foods contribute to maintaining optimal nutritional status and minimizing the likelihood of iron insufficiencies and use of fortified ready-to-eat cereals is a common strategy. The results showed that adding another food source of iron such as pumpkin seed kernels improves the iron status. Additional and longer studies using these two food products are recommended to further determine the effect of iron fortification on iron nutrition and status among the target population, and mainly in young children, adolescents, women of reproductive ages and pregnant women.     

SHANK3 genetic polymorphism and susceptibility to ASD: evidence from molecular,in silico,and meta-analysis approaches

Molecular Biology Reports - The SHANK3 gene encodes a master synaptic scaffolding protein at the excitatory synapse’s postsynaptic density, which is predominantly responsible for constructing...     

Life cycle assessment and life cycle cost of repairing surgical scissors

The International Journal of Life Cycle Assessment - The primary objective of this study was to evaluate the environmental impact and financial cost of repairing surgical scissors. We used life...