CHEST INJURIES AMONG KOREAN CASUALTIES

Major wounds of the chest usually cause immediate or early death. Of 35 patients with major thoracic battle injuries who were treated in one naval hospital, six had non-penetrating wounds of the chest and other areas. Of the 29 with penetrating wounds of the chest, 23 were treated by aspiration of hemothorax, decortication in three cases, and thoracotomy for control of hemorrhage in one case and for removal of a foreign body in another.Four cases are reported, two to illustrate the usual course of treatment and two in which the patient died.     

Photosynthetic characteristics and tolerance to photo-oxidation of transgenic rice expressing C4 photosynthesis enzymes

The photosynthetic characteristics of four transgenic rice lines over-expressing rice NADP-malic enzyme (ME), and maize phosphoenolpyruvate carboxylase (PC), pyruvate,orthophosphate dikinase (PK), and PC+PK (CK) were investigated using outdoor-grown plants. Relative to untransformed wild-type (WT) rice, PC transgenic rice exhibited high PC activity (25-fold increase) and enhanced activity of carbonic anhydrase (more than two-fold increase), while the activity of ribulose-bisphosphate carboxylase/oxygenase (Rubisco) and its kinetic property were not significantly altered. The PC transgenic plants also showed a higher light intensity for saturation of photosynthesis, higher photosynthetic CO₂ uptake rate and carboxylation efficiency, and slightly reduced CO₂ compensation point. In addition, chlorophyll a fluorescence analysis indicates that PC transgenic plants are more tolerant to photo-oxidative stress, due to a higher capacity to quench excess light energy via photochemical and non-photochemical means. Furthermore, PC and CK transgenic rice produced 22–24% more grains than WT plants. Taken together, these results suggest that expression of maize C₄ photosynthesis enzymes in rice, a C₃ plant, can improve its photosynthetic capacity with enhanced tolerance to photo-oxidation. This revised version was published online in June 2006 with corrections to the Cover Date.     

Dominance–diversity relationships in ant communities differ with invasion

The relationship between levels of dominance and species richness is highly contentious, especially in ant communities. The dominance‐impoverishment rule states that high levels of dominance only occur in species‐poor communities, but there appear to be many cases of high levels of dominance in highly diverse communities. The extent to which dominant species limit local richness through competitive exclusion remains unclear, but such exclusion appears more apparent for non‐native rather than native dominant species. Here we perform the first global analysis of the relationship between behavioral dominance and species richness. We used data from 1,293 local assemblages of ground‐dwelling ants distributed across five continents to document the generality of the dominance‐impoverishment rule, and to identify the biotic and abiotic conditions under which it does and does not apply. We found that the behavioral dominance–diversity relationship varies greatly, and depends on whether dominant species are native or non‐native, whether dominance is considered as occurrence or relative abundance, and on variation in mean annual temperature. There were declines in diversity with increasing dominance in invaded communities, but diversity increased with increasing dominance in native communities. These patterns occur along the global temperature gradient. However, positive and negative relationships are strongest in the hottest sites. We also found that climate regulates the degree of behavioral dominance, but differently from how it shapes species richness. Our findings imply that, despite strong competitive interactions among ants, competitive exclusion is not a major driver of local richness in native ant communities. Although the dominance‐impoverishment rule applies to invaded communities, we propose an alternative dominance‐diversification rule for native communities.     

Advanced psychometric testing on a clinical screening tool to evaluate insomnia: sleep condition indicator in patients with advanced cancer

Sleep and Biological Rhythms - To examine the psychometric properties of the Sleep Condition Indicator (SCI) using different psychometric approaches [including classical test theory, Rasch models,...     

Specific Labeling of Stem Cell Activity in Human Colorectal Organoids Using an ASCL2-Responsive Minigene

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Berenil Complexation with a Nucleic Acid Triple Helix

Abstract

The interaction of berenii molecule, a minor groove binding drug, with T-A-T triple helix and A-T double helix was studied using circular dichroism spectroscopy and thermal denaturation. The triple helix was made by an oligonucleotide (dA)₁₂?x-(dT)₁₂?x-(dT)₁₂, where x is a hexaethylene glycol chain bridged between the 3′ phosphate of one strand and the 5′ phosphate of the following strand. This oligonucleotide is able to fold back on itself to form a very stable triplex. Circular dichroism spectroscopy demonstrates that berenil can bind to the triple helical structure. Spectral analysis shows that in the same ionic strength the drug bound to a double-stranded structure exhibits a conformation and an environment close to those observed in triple-stranded structure. The influence of the ionic strength on the interaction between the berenil molecule and the 36-mer is clearly demonstrated. We showed that when no NaCl salt is added in the buffer the triplex form of (dA)₁₂?x-(dT)₁2-x-(dT)₁₂ is stabilized by berenil whereas it is destabilized slightly by the dye when NaCl concentration is 1 M.     

Hypothesis: hyperstructures regulate initiation in Escherichia coli and other bacteria

Hyperstructures or modules have been proposed to constitute a level of organisation intermediate between macromolecules and whole cells. In this model of intracellular organisation, hyperstructures compete and collaborate for existence within the membrane and cytoplasm. Those directly involved in the cell cycle include initiation, replication and division hyperstructures based on DnaA, SeqA and the 2-minute cluster, respectively. During the run-up to initiation, the mass to DNA ratio increases and, we contend, differential gene expression leads to some hyperstructures becoming more active and stable than others. This results in a drop in the diversity of hyperstructures, some of which release DnaA as they dissociate, and a DnaA-initiation hyperstructure forms. Subsequent DNA replication and cell division generate different daughter cells containing different hyperstructures. This has the advantage of increasing the phenotypic diversity of the population. In developing this model, we also invoke hyperstructures in the partitioning of origins of replication.     

Where do adaptive shifts occur during invasion? A multidisciplinary approach to unravelling cold adaptation in a tropical ant species invading the Mediterranean area

Evolution may improve the invasiveness of populations, but it often remains unclear whether key adaptation events occur after introduction into the recipient habitat (i.e. post‐introduction adaptation scenario), or before introduction within the native range (i.e. prior‐adaptation scenario) or at a primary site of invasion (i.e. bridgehead scenario). We used a multidisciplinary approach to determine which of these three scenarios underlies the invasion of the tropical ant Wasmannia auropunctata in a Mediterranean region (i.e. Israel). Species distribution models (SDM), phylogeographical analyses at a broad geographical scale and laboratory experiments on appropriate native and invasive populations indicated that Israeli populations followed an invasion scenario in which adaptation to cold occurred at the southern limit of the native range before dispersal to Israel. We discuss the usefulness of combining SDM, genetic and experimental approaches for unambiguous determination of eco‐evolutionary invasion scenarios.     

Production and Characterization of Monoclonal Antibodies to Wall-Localized Peroxidases from Corn Seedlings

A library of 22 hybridomas, which make antibodies to soluble wall antigens from the coleoptiles and primary leaves of etiolated corn (Zea mays L.) seedlings, was raised and cloned three times by limit dilution to assure monoclonal growth and stability. Two of these hybridomas made immunoglobulin G antibodies, designated mWP3 and mWP19, which both effectively immunoprecipitated peroxidase activity from crude and partially purified preparations of wall peroxidases. Direct peroxidase-binding assays revealed that both antibodies bound enzymes with peroxidase activity. As judged by immunoblot analyses, mWP3 recognized a M_r 98,000 wall peroxidase with an isoelectric point near 4.2, and mWP19 recognized a M_r 58,000 wall peroxidase. Immunogold localization studies showed both peroxidases are predominately in cell walls.     

Analysis of p53 "latency" and "activation" by fluorescence correlation spectroscopy. Evidence for different modes of high affinity DNA binding

The concept that the tumor suppressor p53 is a latent DNA-binding protein that must become activated for sequence-specific DNA binding recently has been challenged, although the "activation" phenomenon has been well established in in vitro DNA binding assays. Using electrophoretic mobility shift assays and fluorescence correlation spectroscopy, we analyzed the binding of "latent" and "activated" p53 to double-stranded DNA oligonucleotides containing or not containing a p53 consensus binding site (DNAspec or DNAunspec, respectively). In the absence of competitor DNA, latent p53 bound DNAspec and DNAunspec with high affinity in a sequence-independent manner. Activation of p53 by the addition of the C-terminal antibody PAb421 significantly decreased the binding affinity for DNAunspec and concomitantly increased the binding affinity for DNAspec. The net result of this dual effect is a significant difference in the affinity of activated p53 for DNAspec and DNAunspec, which explains the activation of p53. High affinity nonspecific DNA binding of latent p53 required both the p53 core domain and the p53 C terminus, whereas high affinity sequence-specific DNA binding of activated p53 was mediated by the p53 core domain alone. The data suggest that high affinity nonspecific DNA binding of latent and high affinity sequence-specific binding of activated p53 to double-stranded DNA differ in their requirement for the C terminus and involve different structural features of the core domain. Because high affinity nonspecific DNA binding of latent p53 is restricted to wild type p53, we propose that it relates to its tumor suppressor functions.