Combining stratification and up-scaling method-block cokriging with remote sensing imagery for sampling and mapping an erosion cover factor

When a ground and vegetation cover factor related to soil erosion is mapped with the aid of remotely sensed data, a cost-efficient sample design to collect ground data and to obtain an accurate map is required. However, the supports used to collect ground data are often smaller than the desirable pixels used for mapping, which leads to complexity in developing procedures for sample design and mapping. For these purposes, a sampling and mapping method was developed by integrating stratification and an up-scaling method in geostatistics — block cokriging with Landsat Thematic Mapper imagery. This method is based on spatial correlation and stratified sampling. It scales up not only the ground sample data but also the uncertainties associated with the data aggregation from smaller supports to larger pixels or blocks. This method uses the advantages of both stratification and block cokriging variance-based sample design, which leads to sample designs with variable grid spacing, and thus significantly increases the unit cost-efficiency of sample data in sampling and mapping. This outcome was verified by the results of this study.     

Male swordtails court with an audience in mind

Females are usually considered to be the target of male courtship behaviour. In nature, however, social interactions rarely occur without other observers; thus, it is conceivable that some male courtship behaviours are directed not towards females, but rather towards male rivals. The northern swordtail, Xiphophorus birchmanni, is a freshwater fish found in high densities in natural streams. Males court by swimming close to and in parallel with the female, raising their large sail-like dorsal fin, and quivering briefly. Here, we show that females prefer males that display small dorsal fins to those with large ones, and that males are less aggressive to other males with large dorsal fins. Male swordtails also raise their dorsal fins more frequently when courting in the presence of other males. These results suggest that, despite female avoidance of large dorsal fins, males that raise their fin during courtship benefit by intimidating potential competitors; the intended receivers of this signal are thus males, not females. Intrasexual selection can therefore offset the forces of intersexual selection, even in a courtship display.     

Experience pays: offspring survival increases with female age

Life-history theory predicts that, in long-lived organisms, effort towards reproduction will increase with age, and research from oviparous vertebrates largely supports this prediction. In reptiles, where parental care occurs primarily via provisioning of the egg, older females tend to produce larger eggs, which in turn produce larger hatchlings that have increased survival. We conducted an experimental release study and report that maternal age positively influences offspring survivorship in the painted turtle (Chrysemys picta) and predicts offspring survival at least as well as hatchling body size does. These data suggest that, although increasing hatchling size is a major component of reproductive success in older individuals, other factors also contribute.     

Nitrosylcobalamin potentiates the anti-neoplastic effects of chemotherapeutic agents via suppression of survival signaling

Background

Nitrosylcobalamin (NO-Cbl) is a chemotherapeutic pro-drug derived from vitamin B12 that preferentially delivers nitric oxide (NO) to tumor cells, based upon increased receptor expression. NO-Cbl induces Apo2L/TRAIL-mediated apoptosis and inhibits survival signaling in a variety of malignant cell lines. Chemotherapeutic agents often simultaneously induce an apoptotic signal and activation of NF-κB, which has the undesired effect of promoting cell survival. The specific aims of this study were to 1) measure the anti-tumor effects of NO-Cbl alone and in combination with conventional chemotherapeutic agents, and to 2) examine the mechanism of action of NO-Cbl as a single agent and in combination therapy.

Methodology

Using anti-proliferative assays, electrophoretic mobility shift assay (EMSA), immunoblot analysis and kinase assays, we demonstrate an increase in the effectiveness of chemotherapeutic agents in combination with NO-Cbl as a result of suppressed NF-κB activation.

Results

Eighteen chemotherapeutic agents were tested in combination with NO-Cbl, in thirteen malignant cell lines, resulting in a synergistic anti-proliferative effect in 78% of the combinations tested. NO-Cbl pre-treatment resulted in decreased NF-κB DNA binding activity, inhibition of IκB kinase (IKK) enzymatic activity, decreased AKT activation, increased caspase-8 and PARP cleavage, and decreased cellular XIAP protein levels.

Conclusion

The use of NO-Cbl to inhibit survival signaling may enhance drug efficacy by preventing concomitant activation of NF-κB or AKT.     

Incudomalleal joint formation: the roles of apoptosis,migration and downregulation

Background  

The middle ear of mammals is composed of three endochondrial ossicles, the stapes, incus and malleus. Joints link the malleus to the incus and the incus to the stapes. In the mouse the first arch derived malleus and incus are formed from a single Sox9 and Type II collagen expressing condensation that later subdivides to give rise to two separate ossicles. In contrast the stapes forms from a separate condensation derived from the second branchial arch. Fusion of the malleus and incus is observed in a number of human syndromes and results in conductive hearing loss. Understanding how this joint forms during normal development is thus an important step in furthering our understanding of such defects.     

Teneurins: transmembrane proteins with fundamental roles in development

Teneurins are a novel family of transmembrane proteins expressed during pattern formation and morphogenesis. Originally discovered as ten-m and ten-a in Drosophila, four vertebrate teneurins as well as a Caenorhabditis elegans homologue were identified. The conserved domain architecture of teneurins includes an intracellular domain containing polyproline motifs. The long extracellular domain consists of eight EGF-like repeats, a region of conserved cysteines and unique YD-repeats. Vertebrate teneurins are most prominently expressed in the developing central nervous system, but are also expressed in developing limbs. In C. elegans, RNAi experiments and studies of mutants reveal that teneurins are required during fundamental developmental processes like cell migration and axon pathfinding. Cell culture experiments suggest that the intracellular domain of teneurins translocates to the nucleus following release from the membrane by proteolytic processing. Interestingly, the human teneurin-1 gene is located on the X-chromosome in a region where several families with X-linked mental retardation are mapped.     

The <Emphasis Type="Italic">PTPN22</Emphasis>1858C/T polymorphism is associated with anti-cyclic citrullinated peptide antibody-positive early rheumatoid arthritis in northern Sweden

The PTPN22 1858C/T polymorphism has been associated with several autoimmune diseases including rheumatoid arthritis (RA). We have shown that carriage of the T variant (CT or TT) of PTPN22 in combination with anti-cyclic citrullinated peptide (anti-CCP) antibodies highly increases the odds ratio for developing RA. In the present study we analysed the association between the PTPN22 1858C/T polymorphism and early RA in patients from northern Sweden, related the polymorphism to autoantibodies and the HLA-DR shared epitope, and analysed their association with markers for disease activity and progression. The inception cohort includes individuals who also donated samples before disease onset. A case–control study was performed in patients (n = 505; 342 females and 163 males) with early RA (mean duration of symptoms = 6.3 months) and in population-based matched controls (n = 970) from northern Sweden. Genotyping of the PTPN22 1858C/T polymorphism was performed using a TaqMan instrument. HLA-shared epitope alleles were identified using PCR sequence-specific primers. Anti-CCP2 antibodies were determined using enzyme-linked immunoassays. Disease activity (that is, the number of swollen and tender joints, the global visual analogue scale, and the erythrocyte sedimentation rate) was followed on a regular basis (that is, at baseline and after 6, 12, 18 and 24 months). Both the 1858T allele and the carriage of T were associated with RA (χ² = 23.84, P = 0.000001, odds ratio = 1.69, 95% confidence interval = 1.36–2.11; and χ² = 22.68, P = 0.000002, odds ratio = 1.79, 95% confidence interval = 1.40–2.29, respectively). Association of the 1858T variant with RA was confined to seropositive disease. Carriage of 1858T and the presence of anti-CCP antibodies was independently associated with disease onset at an earlier age (P < 0.05 and P < 0.01, respectively), while the combination of both resulted in an even earlier age at onset. Smoking was identified as a risk factor independent of the 1858T variant and anti-CCP antibodies.