mtDNA diversity in rhesus monkeys reveals overestimates of divergence time and paraphyly with neighboring species

Reconstructions of the human-African great ape phylogeny by using mitochondrial DNA (mtDNA) have been subject to considerable debate. One confounding factor may be the lack of data on intraspecific variation. To test this hypothesis, we examined the effect of intraspecific mtDNA diversity on the phylogenetic reconstruction of another Plio- Pleistocene radiation of higher primates, the fascicularis group of macaque (Macaca) monkey species. Fifteen endonucleases were used to identify 10 haplotypes of 40-47 restriction sites in M. mulatta, which were compared with similar data for the other members of this species group. Interpopulational, intraspecific mtDNA diversity was large (0.5%- 4.5%), and estimates of divergence time and branching order incorporating this variation were substantially different from those based on single representatives of each species. We conclude that intraspecific mtDNA diversity is substantial in at least some primate species. Consequently, without prior information on the extent of genetic diversity within a particular species, intraspecific variation must be assessed and accounted for when reconstructing primate phylogenies. Further, we question the reliability of hominoid mtDNA phylogenies, based as they are on one or a few representatives of each species, in an already depauperate superfamily of primates.      

Intercellular power transmission along trichomes of cyanobacteria

An attempt at demonstrating lateral power transmission over millimeter distances along a coupling membrane has been undertaken. Trichomes of the multicellular filamentous cyanobacteria Phormidium uncinatum were illuminated with a very narrow light beam forming a light spot that covered only 4–5% of a 1–2 mm long cyanobacterial trichome. Such illumination was found to support motility (gliding along agar surface) of the trichome under conditions when the light was the only energy source. It was also shown that illumination with the light spot caused rotation of rings of slime (accompanying the operation of the ‘motors’ responsible for the motility of cyanobacteria) not only in the illuminated, but also in the distal, nonilluminated part of the trichome. Electric potential transmission along trichomes was revealed by means of the extracellular electrode technique. The light spot was found to induce generation of an electric potential difference between two electrodes in the dark region of the trichomes, which were placed at different distances from the illuminated end. Cutting the trichomes between the light spot and the closest ‘dark’ electrode abolished this effect. Valinomycin + K⁺ and carbonyl cyanide p-trifluoromethoxyphenylhydrazone affected the potential difference formation between two ‘dark’ electrodes much stronger than that between a light and a dark electrode. All the light spot-induced effects develop in the seconds time scale. Both the amplitudes and the kinetics of the potential difference measured with four electrodes placed along the trichome prove to be in good agreement with the theoretical curves computed on the basis of the electric cable equation. It is concluded that transcellular power transmission in the form of Δψ takes place along trichomes of cyanobacteria. This confirms the hypothesis about the biological function of Δψ as a transportable form of energy.     

Functional interaction between information processing pathways in Escherichia coli and the nature of Δ-H+ (redox)-sensing

Glucose taxis and O₂-taxis in Escherichia coli signal to flagella via a pathway that includes PTS^glc and adenylate cyclase. Information from a number of attractants and repellents is focused at the level of methy-accepting chemotaxis proteins (MCPs) and information is passed to flagella by a separate pathway. Mutants defective in adenylate cyclase (Δcya) had a residual taxis to glucose that was eliminated by preincubating the cells with MCP attractants, or by depleting the -CH₃ donor. A methyltransferase mutant had a decreased sensitivity to MCP repellents and this response was completely blocked by preincubating the cells with glucose. Likewise, the response of cells, depleted for -CH₃, towards repellents, was blocked if bacteria carried a pts mutation. It is concluded that PTS and MCP pathways exchange information. In cya cells, O₂ taxis was restored in the presence of maltose, an MCPII attractat. It is suggested that MCPII is an additional protonmotive force (pmf) sensor.     

An invisible ubiquitin conformation is required for efficient phosphorylation by PINK1

The Ser/Thr protein kinase PINK1 phosphorylates the well‐folded, globular protein ubiquitin (Ub) at a relatively protected site, Ser65. We previously showed that Ser65 phosphorylation results in a conformational change in which Ub adopts a dynamic equilibrium between the known, common Ub conformation and a distinct, second conformation wherein the last β‐strand is retracted to extend the Ser65 loop and shorten the C‐terminal tail. We show using chemical exchange saturation transfer (CEST) nuclear magnetic resonance experiments that a similar, C‐terminally retracted (Ub‐CR) conformation also exists at low population in wild‐type Ub. Point mutations in the moving β5 and neighbouring β‐strands shift the Ub/Ub‐CR equilibrium. This enabled functional studies of the two states, and we show that while the Ub‐CR conformation is defective for conjugation, it demonstrates improved binding to PINK1 through its extended Ser65 loop, and is a superior PINK1 substrate. Together our data suggest that PINK1 utilises a lowly populated yet more suitable Ub‐CR conformation of Ub for efficient phosphorylation. Our findings could be relevant for many kinases that phosphorylate residues in folded protein domains.     

From recommendation to action: psychosocial factors influencing physician intention to use Health Technology Assessment (HTA) recommendations

Background

The Evidence-Based Practice (EBP) Project has been investigating the implementation of evidence-based mental health practices (Assertive Community Treatment, Family Psychoeducation, Integrated Dual Diagnosis Treatment, Illness Management and Recovery, and Supported Employment) in state public mental health systems in the United States since 2001. To date, Project findings have yielded valuable insights into implementation strategy characteristics and effectiveness. This paper reports results of an effort to identify and classify state-level implementation activities and strategies employed across the eight states participating in the Project.

Methods

Content analysis and Greenhalgh et al's (2004) definition of innovation were used to identify and classify state-level activities employed during three phases of EBP implementation: Pre-Implementation, Initial Implementation and Sustainability Planning. Activities were coded from site visit reports created from documents and notes from key informant interviews conducted during two periods, Fall 2002 – Spring 2003, and Spring 2004. Frequency counts and rank-order analyses were used to examine patterns of implementation activities and strategies employed across the three phases of implementation.

Results

One hundred and six discreet implementation activities and strategies were identified as innovative and were classified into five categories: 1) state infrastructure building and commitment, 2) stakeholder relationship building and communications, 3) financing, 4) continuous quality management, and 5) service delivery practices and training. Implementation activities from different categories were employed at different phases of implementation.

Conclusion

Insights into effective strategies for implementing EBPs in mental health and other health sectors require qualitative and quantitative research that seeks to: a) empirically test the effects of tools and methods used to implement EBPs, and b) establish a stronger evidence-base from which to plan, implement and sustain such efforts. This paper offers a classification scheme and list of innovative implementation activities and strategies. The classification scheme offers potential value for future studies that seek to assess the effects of various implementation processes, and helps establish widely accepted standards and criteria that can be used to assess the value of innovative activities and strategies.     

Microbial Community Composition of Floodplains Shallow-Water Seeps in the Bolshaya Rechka Floodplain,Western Siberia

Microbiology - Recently discovered fields of seeps in western Siberia are an important, previously unknown source of methane. Seeps are located in the floodplains of small rivers and vary in shape,...     

PARTAKE Survey of Public Knowledge and Perceptions of Clinical Research in India

Background

A public that is an informed partner in clinical research is important for ethical, methodological, and operational reasons. There are indications that the public is unaware or misinformed, and not sufficiently engaged in clinical research but studies on the topic are lacking. PARTAKE – Public Awareness of Research for Therapeutic Advancements through Knowledge and Empowerment is a program aimed at increasing public awareness and partnership in clinical research. The PARTAKE Survey is a component of the program.

Objective

To study public knowledge and perceptions of clinical research.

Methods

A 40-item questionnaire combining multiple-choice and open-ended questions was administered to 175 English- or Hindi-speaking individuals in 8 public locations representing various socioeconomic strata in New Delhi, India.

Results

Interviewees were 18–84 old (mean: 39.6, SD±16.6), 23.6% female, 68.6% employed, 7.3% illiterate, 26.3% had heard of research, 2.9% had participated and 58.9% expressed willingness to participate in clinical research. The following perceptions were reported (% true/% false/% not aware): ‘research benefits society’ (94.1%/3.5%/2.3%), ‘the government protects against unethical clinical research’ (56.7%/26.3%/16.9%), ‘research hospitals provide better care’ (67.2%/8.7%/23.9%), ‘confidentiality is adequately protected’ (54.1%/12.3%/33.5%), ‘participation in research is voluntary’ (85.3%/5.8%/8.7%); ‘participants treated like ‘guinea pigs’’ (20.7%/53.2%/26.0%), and ‘compensation for participation is adequate’ (24.7%/12.9%/62.3%).

Conclusions

Results suggest the Indian public is aware of some key features of clinical research (e.g., purpose, value, voluntary nature of participation), and supports clinical research in general but is unaware of other key features (e.g., compensation, confidentiality, protection of human participants) and exhibits some distrust in the conduct and reporting of clinical trials. Larger, cross-cultural surveys are required to inform educational programs addressing these issues.     

Methane Oxidation in Landfill Cover Soil

Methane oxidation in the cover soil of the Khmet'evo municipal landfill in Moscow oblast was investigated. Methane emission from the experimental site of the landfill was highly heterogeneous. At a depth of 45–60 cm, the pore gas mainly consisted of CH₄ (60–70%) and CO₂ (30–40%). In the upper layers of the cover soil, the concentration of these gases sharply decreased. Methods for estimation of the methane-oxidizing activity in the cover soil of the landfill were tested. The rate of methane oxidation in the soil correlated with the cell number of culturable methanotrophic bacteria and was the factor limiting methane emission from the surface of the landfill. The method of indirect immunofluorescence revealed ten known species of methanotrophic bacteria in enrichment cultures obtained from samples of the cover soil. Our results also indicate the presence of unknown psychrotolerant methanotrophs that are active at the low temperatures characteristic of Moscow oblast.