Novel selenoorganic compounds as modulators of oxidative stress in blood platelets

Many selenoorganic compounds play an important role in biochemical processes and act as antioxidants, enzyme inhibitors, or drugs. The effects of five new synthesized selenoorganic compounds (2-(5-chloro-2-pyridyl)-7-azabenzisoselenazol-3(2H)-one; 2-phenyl-7-azabenzisoselenazol-3(2H)-one; 2-(pyridyl)-7-azabenzisoselenazol-3(2H)-one; 7-azabenzisoselenazol-3(2H)-one; bis(2-aminophenyl) diselenide) on oxidative changes in human blood platelets and in plasma were studied in vitro and compared with those of ebselen, a well known antioxidant. Our studies demonstrated that bis(2-aminophenyl) diselenide has distinctly protective effects against oxidative stress in blood platelets and in plasma. It might have greater biological relevance and stronger pharmacological effects than ebselen.     

Self-Interest and the Design of Rules

Rules regulating social behavior raise challenging questions about cultural evolution in part because they frequently confer group-level benefits. Current multilevel selection theories contend that between-group processes interact with within-group processes to produce norms and institutions, but within-group processes have remained underspecified, leading to a recent emphasis on cultural group selection as the primary driver of cultural design. Here we present the self-interested enforcement (SIE) hypothesis, which proposes that the design of rules importantly reflects the relative enforcement capacities of competing parties. We show that, in addition to explaining patterns in cultural change and stability, SIE can account for the emergence of much group-functional culture. We outline how this process can stifle or accelerate cultural group selection, depending on various social conditions. Self-interested enforcement has important bearings on the emergence, stability, and change of rules.     

Long-term platinum retention after treatment with cisplatin and oxaliplatin

Background  

The aim of this study was to evaluate long-term platinum retention in patients treated with cisplatin and oxaliplatin.     

A spatial analytical approach for selecting reintroduction sites for burbot in English rivers

1. Availability of suitable habitat is a prerequisite for species reintroduction success, and to ensure population persistence, investigations of a species’ habitat utilisation throughout its life history should be conducted as part of a feasibility study. 2. Habitat utilisation models for burbot, Lota lota, developed using data from field studies conducted in France and Germany and information from the literature were used to assess the feasibility of reintroducing burbot into rivers of its former native range in eastern England. 3. Per cent tree roots, aquatic vegetation and flow types were important predictors of adult burbot abundance. Furthermore, the habitat utilisation models were supplemented with information from the literature, which suggested that off‐channel habitat such as wetlands and backwaters is important for spawning and nursery stages. 4. An assessment of the habitat availability in the rivers of the burbot’s former native range using variables related to spawning and nursery and adult life stages showed that although adult habitat was widely distributed, the availability of spawning and nursery habitat was less abundant, potentially limiting successful reestablishment. 5. Potential suitable habitat was concentrated in the central and southern areas of the species’ former English distribution. Overall, rivers of the burbot’s former range potentially afford suitable habitat to sustain a reintroduced population. However, sites should be preferentially selected on the basis of having appropriate spawning and nursery areas.     

Antigenicity of human melanoma cells transfected to express the B7-1 co-stimulatory molecule (CD80) varies with the level of B7-1 expression

 The aim of this study was to compare the antigenicity of human melanoma cells molecularly modified by particle-mediated gene transfer to have transient or stable expression of the B7-1 co-stimulatory molecule (CD80). The unmodified melanoma cells (mel5, m21) had no constitutive expression of B7-1, but 22%–28% of cells had transient B7-1 expression 24 h following transfection with cDNA for B7-1 (mel5-B7, m21-B7). In addition, 85%–90% of cells had stable B7-1 expression following transfection with cDNA for B7-1 and in vitro culture under selection conditions (mel5-B7neo, m21-B7neo). Allogeneic HLA-unmatched normal donor peripheral blood mononuclear cells (PBMC) secreted greater amounts of granulocyte/macrophage-colony-stimulating factor (GM-CSF) when incubated for 3 days with m21-B7neo than did PBMC incubated with m21-B7, which, in turn, secreted greater amount of GM-CSF than PBMC incubated with m21. Similarly, cell-mediated cytotoxicity against unmodified melanoma cells by PBMC co-cultured for 5 days with the modified or unmodified melanoma cells was proportional to the level of B7-1 expression on the stimulating cells. This cytolytic activity had both an HLA-class-I-restricted and an HLA-class-I-unrestricted component. Following 5 days of co-culture, PBMC expression of CD28, the ligand for B7-1, was down-regulated in proportion to the level of B7-1 expression on the stimulating melanoma cells. Thus, particle-mediated gene delivery of cDNA for B7-1 into human melanoma cells increased expression of functional B7-1 and enhanced the antigenicity of the gene-modified cells in proportion to their level of B7-1 expression. Received: 14 October 1999 / Accepted: 3 December 1999     

Presence of Bartonella and Rickettsia spp. in cat fleas and brown dog ticks collected from dogs in American Samoa

Surveys for ectoparasites of dogs on the American Samoa islands of Aunu'u and Tutuila were conducted in June 2012, and was followed by molecular screening of samples. One species of flea, Ctenocephalides felis, and one tick species, Rhipicephalus sanguineus, were collected and tested for Bartonella and Rickettsia species via PCR. Bartonella clarridgeiae and an unnamed spotted fever group Rickettsia were detected in the fleas; the Rickettsia species was previously reported from Ctenocephalides spp. from Egypt, Thailand, USA, and the Republic of the Marshall Islands. None of the ticks were positive for Bartonella or Rickettsia species. This is the first report of flea-borne Rickettsia and B. clarridgeiae, considered an emerging human pathogen in New Zealand, from American Samoa. Ectoparasite-borne infections are easily misdiagnosed or ignored as their symptoms are often vague and similar to other illnesses (e.g., measles, dengue). Our results indicate a potential threat to human and animal health as infected fleas were collected from household pets.