Effect of Metalaxyl on the incidence and severity of Pearl millet downy mildew disease in Northern Nigeria

Pearl millet downy mildew (DM) incidence, severity and yield losses of two pearl millet varieties (local and improved) due to the disease were determined in the field. Significant differences in the disease incidence and severity were recorded in the plots sown with metalaxyl-treated seeds and those sown with non-treated seeds, indicating the efficacy of the fungicide on the fungus. Yield losses due to non-treatment of seeds with metalaxyl was 40.88 and 45.39% in a local variety and 43.00 and 18.60% in an improved variety in the 2000 and 2001 cropping seasons respectively. Significant differences between plots sown with metalaxyl-treated and those sown with non-treated seeds were obtained for other yield components such as 1000-grains weight, panicle length and weight.     

Airborne pollen and spores on the Arctic island of Jan Mayen

A survey of airspora collected on Jan Mayen, an isolated North Atlantic island (71°N, 8°30′W), using a Burkard seven-day volumetric trap from 24th April to 31th August, 1988, revealed only very small concentrations. A total of 10 different pollen types were recorded, constituting a seasonal sum of 29 pollen grains. The local pollen season was confined to July, with Oxyria digna and Salix as the most numerous pollen types recorded. Exotic pollen grains, namely Betula, Pinus and Castanea type, were recorded in three periods during June and July. Studies of back trajectories indicate North America and/or Iceland and Greenland as possible source areas for the Betula pollen. There were more diatoms than pollen in the local airspora. Fungal spores mainly occurred in late July and August. Cladosporium constituted less than 5% of the total seasonal sum of fungal spores, while basidiospores contributed nearly 12%. The highest diurnal average of Cladosporium was 27 spores m^?3 air. The seasonal maximum of unidentified fungal spores reached a diurnal average of 639 spores m^?1 air on 27th August.     

The catalytic domain CysPc of the DEK1 calpain is functionally conserved in land plants

DEK1, the single calpain of land plants, is a member of the ancient membrane bound TML–CysPc–C2L calpain family that dates back 1.5 billion years. Here we show that the CysPc–C2L domains of land plant calpains form a separate sub‐clade in the DEK1 clade of the phylogenetic tree of plants. The charophycean alga Mesostigma viride DEK1‐like gene is clearly divergent from those in land plants, suggesting that a major evolutionary shift in DEK1 occurred during the transition to land plants. Based on genetic complementation of the Arabidopsis thaliana dek1‐3 mutant using CysPc–C2L domains of various origins, we show that these two domains have been functionally conserved within land plants for at least 450 million years. This conclusion is based on the observation that the CysPc–C2L domains of DEK1 from the moss Physcomitrella patens complements the A. thaliana dek1‐3 mutant phenotype. In contrast, neither the CysPc–C2L domains from M. viride nor chimeric animal–plant calpains complement this mutant. Co‐evolution analysis identified differences in the interactions between the CysPc–C2L residues of DEK1 and classical calpains, supporting the view that the two enzymes are regulated by fundamentally different mechanisms. Using the A. thaliana dek1‐3 complementation assay, we show that four conserved amino acid residues of two Ca²⁺‐binding sites in the CysPc domain of classical calpains are conserved in land plants and functionally essential in A. thaliana DEK1.     

The diagnostic value of reproductive organs in some genera of articulated Coralline red algae

Clearcut differences exist between the reproductive organs of Corallina and Jania. Fully formed spermatangial conceptacles in Corallina have low ceillings and pronounced beaks whereas in Jania they have high ceilings and lack beaks. Fusion cells in carposporophytic conceptacles are thin and broad in the former genus and thick and narrow in the latter. Tetrasporangial conceptacles have less capacity in Jania than in Corallina and the fertile areas in young conceptacles cover a smaller area.

Haliptylon is changed from group to generic status and Corallina subulata is transferred to this genus. Haliptylon is characterised by conceptacles similar in all known respects to those of Jania, but the branching is pinnate, as in Corallina.

From the available evidence it appears possible that organisms having Corallina-type conceptacles diverged phylogenetically long ago from those having Jania-type conceptacles.     

Mid- to Long-Term Outcomes of Cervical Disc Arthroplasty versus Anterior Cervical Discectomy and Fusion for Treatment of Symptomatic Cervical Disc Disease: A Systematic Review and Meta-Analysis of Eight Prospective Randomized Controlled Trials

Purpose

This study aimed to investigate the mid- to long-term outcomes of cervical disc arthroplasty (CDA) versus anterior cervical discectomy and fusion (ACDF) for the treatment of 1-level or 2-level symptomatic cervical disc disease.

Methods

Medline, Embase, and the Cochrane Central Register of Controlled Trials databases were searched to identify relevant randomized controlled trials that reported mid- to long-term outcomes (at least 48 months) of CDA versus ACDF. All data were analyzed by Review Manager 5.3 software. The relative risk (RR) and 95% confidence intervals (CIs) were calculated for dichotomous variables. The weighted mean difference (WMD) and 95%CIs were calculated for continuous variables. A random effect model was used for heterogeneous data; otherwise, a fixed effect model was used.

Results

Eight prospective randomized controlled trials (RCTs) were retrieved in this meta-analysis, including 1317 and 1051 patients in CDA and ACDF groups, respectively. Patients after an ACDF had a significantly lower rate of follow-up than that after CDA. Pooled analysis showed patients in CDA group achieved significantly higher rates of overall success, Neck Disability Index (NDI) success, neurological success and significantly lower rates of implant/surgery-related serious adverse events and secondary procedure compared with that in ACDF group. The long-term functional outcomes (NDI, Visual Analog Scale (VAS) neck and arm pain scores, the Short Form 36 Health Survey physical component score (SF-36 PCS)), patient satisfaction and recommendation, and the incidence of superior adjacent segment degeneration also favored patients in CDA group with statistical difference. Regarding inferior adjacent segment degeneration, patients in CDA group had a lower rate without statistical significance.

Conclusions

This meta-analysis showed that cervical disc arthroplasty was superior over anterior discectomy and fusion for the treatment of symptomatic cervical disc disease in terms of overall success, NDI success, neurological success, implant/surgery-related serious adverse events, secondary procedure, functional outcomes, patient satisfaction and recommendation, and superior adjacent segment degeneration.     

Pre‐adapting parasitic phages to a pathogen leads to increased pathogen clearance and lowered resistance evolution with Pseudomonas aeruginosa cystic fibrosis bacterial isolates

Recent years have seen renewed interest in phage therapy – the use of viruses to specifically kill disease‐causing bacteria – because of the alarming rise in antibiotic resistance. However, a major limitation of phage therapy is the ease at with bacteria can evolve resistance to phages. Here, we determined whether in vitro experimental coevolution can increase the efficiency of phage therapy by limiting the resistance evolution of intermittent and chronic cystic fibrosis Pseudomonas aeruginosa lung isolates to four different phages. We first pre‐adapted all phage strains against all bacterial strains and then compared the efficacy of pre‐adapted and nonadapted phages against ancestral bacterial strains. We found that evolved phages were more efficient in reducing bacterial densities than ancestral phages. This was primarily because only 50% of bacterial strains were able to evolve resistance to evolved phages, whereas all bacteria were able to evolve some level of resistance to ancestral phages. Although the rate of resistance evolution did not differ between intermittent and chronic isolates, it incurred a relatively higher growth cost for chronic isolates when measured in the absence of phages. This is likely to explain why evolved phages were more effective in reducing the densities of chronic isolates. Our data show that pathogen genotypes respond differently to phage pre‐adaptation, and as a result, phage therapies might need to be individually adjusted for different patients.     

Arbovirus surveillance using FTATM cards in modified CO2‐baited encephalitis virus surveillance traps in the Northern Territory,Australia

In 2016, modified CO₂‐baited encephalitis virus surveillance (EVS) traps were evaluated for flavivirus surveillance in the Northern Territory, Australia. The traps were fitted with honey‐soaked nucleic acid preservation cards (FTA^TM) for mosquitoes to expectorate virus while feeding on the cards. Cards were tested for the presence of selected arboviruses, with two cards testing positive for Kunjin virus and Alfuy, while sentinel chickens tested in parallel also showed Kunjin virus activity at the same time. The results from the cards and vector mosquito feeding rates indicate that CO₂‐baited EVS traps coupled with honey‐baited FTA^TM cards are an effective tool for broad‐scale arbovirus surveillance.     

Gene expression and the evolution of phenotypic diversity in social wasps

Background  

Organisms are capable of developing different phenotypes by altering the genes they express. This phenotypic plasticity provides a means for species to respond effectively to environmental conditions. One of the most dramatic examples of phenotypic plasticity occurs in the highly social hymenopteran insects (ants, social bees, and social wasps), where distinct castes and sexes all arise from the same genes. To elucidate how variation in patterns of gene expression affects phenotypic variation, we conducted a study to simultaneously address the influence of developmental stage, sex, and caste on patterns of gene expression in Vespula wasps. Furthermore, we compared the patterns found in this species to those found in other taxa in order to investigate how variation in gene expression leads to phenotypic evolution.