Heterokaryon Incompatibility Genes in NEUROSPORA CRASSA Detected Using Duplication-Producing Chromosome Rearrangements

Evidence is presented for five or six previously undetected heterokaryon incompatibility (het) loci, bringing to about ten the number of such genes known in Neurospora crassa. The genes were detected using chromosome duplications (partial diploids), on the basis of properties previously known for het genes in duplications. Duplications homozygous for het genes are usually normal in growth and morphology, whereas those heterozygous are strikingly different. The heterozygotes are inhibited in their initial growth, produce brown pigment on appropriate medium, and later "escape" from their inhibition, as a result of somatic events, to produce wild-type growth. - Five normal-sequence strains were crossed to 14 duplication-producing chromosome rearrangements, and the duplication progeny were examined for properties characteristic of duplications heterozygous for known het genes. Each cross produced duplications for a specific region of the genome, depending on the rearrangement. Normal-sequence strains were wild types from nature, chosen from diverse geographic locations to serve as sources of genetic variation. - The duplication method was very effective. Most of the longer duplications uncovered het genes. The genes are: het-5 (on linkage group IR, in the region covered by duplications produced using rearrangement T (IR LEADS TO VIR)NM103), het-6 (on IIL, covered by T(IIL LEADS TO VI)P2869 and T(IIL LEADS TO IIIR)AR18 duplications), het-7 (tentatively assigned to IIIR, T(IIIR LEADS TO VIL)D305), het-8 (VIL, T(VIL LEADS TO IR)T39M777), het-9 (VIR LEADS TO IVR)AR209), and het-10 (VIIR, T(VIIR LEADS TO IL)5936.     

Probiotics, prebiotics and antioxidants as functional foods

The term "functional foods" comprises some bacterial strains and products of plant and animal origin containing physiologically active compounds beneficial for human health and reducing the risk of chronic diseases. Among the best known functional compounds probiotics, prebiotics and natural antioxidants should be given as examples. These substances can be obtained by biotechnological methods and by extraction from plant or animal tissues.     

Cell-free N-terminal protein labeling using initiator suppressor tRNA

A highly efficient method for the introduction of fluorophores and other markers at the N terminus of proteins produced in a cell-free extract has been developed. The method utilizes an amber (CUA) initiator suppressor tRNA chemically aminoacylated with a fluorophore-amino acid conjugate which is introduced into an Escherichia coli S30 cell-free translation system. The DNA template contains a complementary amber (UAG) codon instead of the normal initiation (AUG) codon. Using this approach, the fluorophore BODIPY-F1 (4,4-difluoro-5,7-dimethyl-4-bora-3a,4a- diaza-s-indacene-3-propionic acid) has been incorporated at the N terminus of several model proteins. The specific labeling achieved (27-67%) using this approach is much higher than that of wild-type tRNAs. Several potential biophysical and biotechnological applications of this new technology are described.     

The Spontaneous Rearrangement of 2,4-Dinitrophenyl Substituent in Ribonucleosides Under Neutral Conditions

In the cytidine and adenosine derivatives an isomerization of a 2,4-dinitrophenyl group between the 2′- and 3′-positions of the ribose was observed under neutral conditions. Moreover, it was shown that isomerization of the 2,4-dinitrophenyl group in conditions required to synthesize phosphoramidites and lability in aqueous ammonia make chemical synthesis of 2′-O-(2,4-dinitrophenyl) oligonucleotides impossible.     

Naturopathic medicine for the prevention of cardiovascular disease: a randomized clinical trial

Background:Although cardiovascular disease may be partially preventable through dietary and lifestyle-based interventions, few individuals at risk receive intensive dietary and lifestyle counselling. We performed a randomized controlled trial to evaluate the effectiveness of naturopathic care in reducing the risk of cardiovascular disease.Methods:We performed a multisite randomized controlled trial of enhanced usual care (usual care plus biometric measurement; control) compared with enhanced usual care plus naturopathic care (hereafter called naturopathic care). Postal workers aged 25–65 years in Toronto, Vancouver and Edmonton, Canada, with an increased risk of cardiovascular disease were invited to participate. Participants in both groups received care by their family physicians. Those in the naturopathic group also received individualized care (health promotion counselling, nutritional medicine or dietary supplementation) at 7 preset times in work-site clinics by licensed naturopathic doctors. The body weight, waist circumference, lipid profile, fasting glucose levels and blood pressure of participants in both groups were measured 3 times during a 1-year period. Our primary outcomes were the 10-year risk of having a cardiovascular event (based on the Framingham risk algorithm) and the prevalence of metabolic syndrome (based on the Adult Treatment Panel III diagnostic criteria).Results:Of 246 participants randomly assigned to a study group, 207 completed the study. The characteristics of participants in both groups were similar at baseline. Compared with participants in the control group, at 52 weeks those in the naturopathic group had a reduced adjusted 10-year cardiovascular risk (control: 10.81%; naturopathic group: 7.74%; risk reduction −3.07% [95% confidence interval (CI) −4.35% to −1.78%], p < 0.001) and a lower adjusted frequency of metabolic syndrome (control group: 48.48%; naturopathic care: 31.58%; risk reduction −16.90% [95% CI −29.55% to −4.25%], p = 0.002).Interpretation:Our findings support the hypothesis that the addition of naturopathic care to enhanced usual care may reduce the risk of cardiovascular disease among those at high risk. Trial registration: ClinicalTrials.gov, no. NCT0071879.Cardiovascular disease is the second leading cause of death in Canada.¹ Observational studies, including a large international case–control study, have shown that several modifiable behavioural factors contribute to the risk of cardiovascular disease.² Metabolic syndrome, a cluster of modifiable risk factors for atherosclerotic cardiovascular disease, is strongly associated with increased risk of cardiovascular-related mortality.^3,4 Guidelines by the American Heart Association and the United States Preventive Services Task Force recommend lifestyle interventions as an important part of cardiovascular disease prevention.^5,6 Although the importance of lifestyle intervention is widely recognized, few individuals with, or at risk of, cardiovascular disease receive intensive dietary and lifestyle counselling.^7,8A variety of health care practitioners routinely deliver diet and health promotion advice to patients at risk of cardiovascular disease. Naturopathic doctors in North America are trained and regulated practitioners who emphasize this form of self-directed care. Several retrospective analyses have suggested that patients at risk of cardiovascular disease receive lifestyle counselling routinely as part of naturopathic care.^9–11 However, no rigorous studies have examined the effectiveness of these approaches. To evaluate the effectiveness of representative naturopathic approaches to reducing the risk of cardiovascular disease, we conducted a randomized clinical trial of a multimodality nutritional and physical activity intervention in a workplace setting.     

Divergent apparent temperature sensitivity of terrestrial ecosystem respiration

Aims Recent studies revealed convergent temperature sensitivity of ecosystem respiration (R e) within aquatic ecosystems and between terrestrial and aquatic ecosystems. We do not know yet whether various terrestrial ecosystems have consistent or divergent temperature sensitivity. Here, we synthesized 163 eddy covariance flux sites across the world and examined the global variation of the apparent activation energy (Ea), which characterizes the apparent temperature sensitivity of and its interannual variability (IAV) as well as their controlling factors.Methods We used carbon fluxes and meteorological data across FLUXNET sites to calculate mean annual temperature, temperature range, precipitation, global radiation, potential radiation, gross primary productivity and R e by averaging the daily values over the years in each site. Furthermore, we analyzed the sites with>8 years data to examine the IAV of Ea and calculated the standard deviation of Ea across years at each site to characterize IAV.Important findings The results showed a widely global variation of Ea, with significantly lower values in the tropical and subtropical areas than in temperate and boreal areas, and significantly higher values in grasslands and wetlands than that in deciduous broadleaf forests and evergreen forests. Globally, spatial variations of Ea were explained by changes in temperature and an index of water availability with differing contribution of each explaining variable among climate zones and biomes. IAV and the corresponding coefficient of variation of Ea decreased with increasing latitude, but increased with radiation and corresponding mean annual temperature. The revealed patterns in the spatial and temporal variations of Ea and its controlling factors indicate divergent temperature sensitivity of R e, which could help to improve our predictive understanding of R e in response to climate change.     

Atrazine degradation by aerobic microorganisms isolated from the rhizosphere of sweet flag (Acorus calamus L.)

In presented study the capability of microorganisms isolated from the rhizosphere of sweet flag (Acorus calamus) to the atrazine degradation was assessed. Following isolation of the microorganisms counts of psychrophilic bacteria, mesophilic bacteria and fungi were determined. Isolated microorganisms were screened in terms of their ability to decompose a triazine herbicide, atrazine. Our results demonstrate that within the rhizosphere of sweet flag there were 3.8 × 10⁷ cfu of psychrophilic bacteria, 1.8 × 10⁷ cfu of mesophilic bacteria, and 6 × 10⁵ cfu of fungi per 1 g of dry root mass. These microorganisms were represented by more than 20 different strains, and at the first step these strains were grown for 5 days in the presence of atrazine at a concentration of 5 mg/l. In terms of the effect of this trial culture, the bacteria reduced the level of atrazine by an average of about 2–20%, but the average level of reduction by fungi was in the range 18–60%. The most active strains involved in atrazine reduction were then selected and identified. These strains were classified as Stenotrophomonas maltophilia, Bacillus licheniformis, Bacillus megaterium, Rahnella aquatilis (three strains), Umbelopsis isabellina, Volutella ciliata and Botrytis cinerea. Culturing of the microorganisms for a longer time resulted in high atrazine degradation level. The highest degradation level was observed at atrazine concentrations of 5 mg/l for S. maltophilia (83.5% after 15 days of culture) and for Botrytis sp. (82% after 21 days of culture). Our results indicate that microorganisms of the sweet flag rhizosphere can play an important role in the bioremediation of atrazine-contaminated sites.     

Plasma membrane components of adherens junctions (Review)

This review focuses on the three known plasma membrane components of adherens junctions: E-cadherin, nectin-2 and vezatin. The structures of these three components are discussed, with particular emphasis on the molecular mechanisms by which E-cadherin and nectin-2 promote cell adhesion.     

Tight junction peptide antagonists enhance neutrophil trans-endothelial chemotaxis

Occludin is an integral membrane protein within tight junctions. Previous studies suggest it functions as a sealing element, which promotes barrier in endothelial and epithelial cell layers. Here, we examine the role of occludin in neutrophil chemotaxis, using cyclic occludin peptide antagonists that incorporate a conserved occludin cell adhesion recognition (CAR) sequence. Human umbilical vein endothelial cells were pre-treated with occludin specific cyclic peptide antagonists to examine effects on neutrophil migration towards a chemotactic gradient of 10(-7) M fMLP. The spatial organization of occludin and VE-cadherin were also assessed in control and occludin peptide-treated monolayers by immunofluorescent staining. The cyclic peptide, peptide B, which contains the CAR sequence of occludin, increased neutrophil chemotaxis in a time and dose dependent manner. Scrambled sequence peptide controls and linear peptides did not. The cyclic occludin antagonist, peptide B, disorganized junctional occludin, but apparently not VE-cadherin as assessed by immunofluorescence. The correlation between diminished occludin organization and increased neutrophil trans-endothelial chemotaxis provides additional support for occludin in the maintenance of the tight junctional barrier.