Gene duplication in an African cichlid adaptive radiation

Background Gene duplication is a source of evolutionary innovation and can contribute to the divergence of lineages; however, the relative importance of this process remains to be determined. The explosive divergence of the African cichlid adaptive radiations provides both a model for studying the general role of gene duplication in the divergence of lineages and also an exciting foray into the identification of genomic features that underlie the dramatic phenotypic and ecological diversification in this particular lineage. We present the first genome-wide study of gene duplication in African cichlid fishes, identifying gene duplicates in three species belonging to the Lake Malawi adaptive radiation (Metriaclima estherae, Protomelas similis, Rhamphochromis “chilingali”) and one closely related species from a non-radiated riverine lineage (Astatotilapia tweddlei). Results Using Astatotilapia burtoni as reference, microarray comparative genomic hybridization analysis of 5689 genes reveals 134 duplicated genes among the four cichlid species tested. Between 51 and 55 genes were identified as duplicated in each of the three species from the Lake Malawi radiation, representing a 38%–49% increase in number of duplicated genes relative to the non-radiated lineage (37 genes). Duplicated genes include several that are involved in immune response, ATP metabolism and detoxification. Conclusions These results contribute to our understanding of the abundance and type of gene duplicates present in cichlid fish lineages. The duplicated genes identified in this study provide candidates for the analysis of functional relevance with regard to phenotype and divergence. Comparative sequence analysis of gene duplicates can address the role of positive selection and adaptive evolution by gene duplication, while further study across the phylogenetic range of cichlid radiations (and more generally in other adaptive radiations) will determine whether the patterns of gene duplication seen in this study consistently accompany rapid radiation

Potassium and magnesium mediate the light and co2 photosynthetic responses of grapevines

Potassium (K) and magnesium (Mg) deficiency are common stresses that can impact on grape yield and quality, but their effects on photosynthesis have received little attention. Understanding the diffusional and biochemical limitations to photosynthetic constraints will help to guide improvements in cultural practices. Accordingly, the photosynthetic response of Vitis vinifera cvs. Shiraz and Chardonnay to K or Mg deficiency was assessed under hydroponic conditions using miniature low-nutrient-reserve vines. Photosynthesis was at least partly reduced by a decline in stomatal conductance. Light and CO2-saturated photosynthesis, maximum rate of ribulose 1.5 bisphospate (RuBP) carboxylation (Vcmax) and maximum rate of electron transport (Jmax) all decreased under K and Mg deficiency. Likewise, chlorophyll fluorescence and electron transport were lower under both nutrient deficiencies while dark respiration increased. K deficiency drastically reduced shoot biomass in both cultivars, while root biomass was greatly reduced under both Mg and K deficiency. Taken together, these results indicate that the decrease in biomass was likely due to both stomatal and biochemical limitations in photosynthesis. Optimising photosynthesis through adequate nutrition will thus support increases in biomass with carry-on positive effects on crop yields

The Genomic Substrate for Adaptive Radiation: Copy Number Variation across 12 Tribes of African Cichlid Species

© 2019 Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution 2019. This work is written by US Government employees and is in the public domain in the US. The initial sequencing of five cichlid genomes revealed an accumulation of genetic variation, including extensive copy number variation in cichlid lineages particularly those that have undergone dramatic evolutionary radiation. Gene duplication has the potential to generate substantial molecular substrate for the origin of evolutionary novelty. We use array-based comparative heterologous genomic hybridization to identify copy number variation events (CNVEs) for 168 samples representing 53 cichlid species including the 5 species for which full genome sequence is available. We identify an average of 50-100 CNVEs per individual. For those species represented by multiple samples, we identify 150-200 total CNVEs suggesting a substantial amount of intraspecific variation. For these species, only ∼10% of the detected CNVEs are fixed. Hierarchical clustering of species according to CNVE data recapitulates phylogenetic relationships fairly well at both the tribe and radiation level. Although CNVEs are detected on all linkage groups, they tend to cluster in "hotspots" and are likely to contain and be flanked by transposable elements. Furthermore, we show that CNVEs impact functional categories of genes with potential roles in adaptive phenotypes that could reasonably promote divergence and speciation in the cichlid clade. These data contribute to a more complete understanding of the molecular basis for adaptive natural selection, speciation, and evolutionary radiation

HPLC-DAD stability indicating determination of nizatidine in bulk and capsules dosage form

AbstractThis work describes the stability-indicating determination of the H2-receptor antagonist nizatidine in its bulk and capsules dosage form using high performance liquid chromatography coupled with diode array detector (HPLC-DAD). The developed method involved the use of Thermo Hypersil BDS-C8 (4.6×250mm, 5μm particle size) column and a mobile phase composed of 0.05M phosphoric acid and acetonitrile (50:50, v/v). The mobile phase was pumped at a flow rate of 1mL/min. Quantification of nizatidine was based on measuring its peak area at 320nm. The retention time for nizatidine was about 3.61min. The reliability and analytical performance of the proposed HPLC procedure were statistically validated with respect to linearity, range, precision, accuracy, specificity, robustness, detection and quantification limits. Calibration curve of nizatidine was linear in the range of 5–50μg/mL with correlation coefficient >0.9999. The drug was subjected to forced-degradation conditions of acidic and basic hydrolysis, oxidation, dry heat and UV photolysis where it showed considerable degradation in basic and oxidative conditions. The proposed method proved to be specific and stability-indicating by resolution of the drug from its forced-degradation products. The validated HPLC method was applied to the analysis of nizatidine in capsules dosage form where it was quantified with recoveries not less than 98.2%. Assay results were statistically compared to USP 2011 pharmacopeial method where no significant difference was observed between the proposed and reference methods

Gene duplication in an African cichlid adaptive radiation

BACKGROUND: Gene duplication is a source of evolutionary innovation and can contribute to the divergence of lineages; however, the relative importance of this process remains to be determined. The explosive divergence of the African cichlid adaptive radiations provides both a model for studying the general role of gene duplication in the divergence of lineages and also an exciting foray into the identification of genomic features that underlie the dramatic phenotypic and ecological diversification in this particular lineage. We present the first genome-wide study of gene duplication in African cichlid fishes, identifying gene duplicates in three species belonging to the Lake Malawi adaptive radiation (Metriaclima estherae, Protomelas similis, Rhamphochromis “chilingali”) and one closely related species from a non-radiated riverine lineage (Astatotilapia tweddlei). RESULTS: Using Astatotilapia burtoni as reference, microarray comparative genomic hybridization analysis of 5689 genes reveals 134 duplicated genes among the four cichlid species tested. Between 51 and 55 genes were identified as duplicated in each of the three species from the Lake Malawi radiation, representing a 38%–49% increase in number of duplicated genes relative to the non-radiated lineage (37 genes). Duplicated genes include several that are involved in immune response, ATP metabolism and detoxification. CONCLUSIONS: These results contribute to our understanding of the abundance and type of gene duplicates present in cichlid fish lineages. The duplicated genes identified in this study provide candidates for the analysis of functional relevance with regard to phenotype and divergence. Comparative sequence analysis of gene duplicates can address the role of positive selection and adaptive evolution by gene duplication, while further study across the phylogenetic range of cichlid radiations (and more generally in other adaptive radiations) will determine whether the patterns of gene duplication seen in this study consistently accompany rapid radiation

The relation between ST-segment resolution and in-hospital mortality after primary percutaneous coronary interventions

Objective: The resolution of ST-segment elevation (>50%) indicates successful reperfusion with thrombolytic therapy. The aim of this study is to evaluate the relation of ST-segment resolution post-primary percutaneous cardiac intervention (PCI) with in-hospital mortality and coronary thrombolysis in myocardial infarction (TIMI) blood flow. Methods: This study is a single-centred retrospective study. The study enrolled 100 patients who were referred to the Nasiriya Heart Centre for primary PCI. We measured the ST segment amplitude in the lead with the highest elevation prior to primary PCI and assessed the ST-segment elevation post-primary PCI. The ratio of ST-segment resolution was calculated and considered complete if reaches ≥70% from the initial ST-segment elevation. We assessed the association of ST-segment resolution with in-hospital mortality. Results: Analysis of the electrocardiogram (ECG) showed that 21 patients (21%) had complete ST-segment (≥ 70%) resolution. No significant association was shown between ST-segment resolution and in-hospital mortality. Two out of 21 patients with complete ST-segment resolution died in the hospital and 6 out of 79 patients with incomplete ST-segment resolution died (P=0.77). There is no significant association between ST-segment resolution and coronary TIMI flow grades. In patients with complete ST-segment resolution, 19 patients had TIMI III flow and 2 patients had TIMI II flow. In patients with incomplete ST-segment resolution, 72 patients had TIMI III flow, 6 patients had TIMI II flow; and 1 patient had no-reflow (P=0.84). Conclusion: Complete ST-segment resolution in post-primary PCI settings has no significant association with in-hospital mortality. Absent or incomplete ST-segment resolution is not necessarily an indicator of coronary artery re-occlusion after primary PCI

Effectiveness of Mindfulness Therapy among Adolescent with Conduct Disorder in Jakarta, Indonesia

AbstractBackgr*ound and objectives: The prevalence of adolescent conduct disorder (CD) among school in Jakarta is 26,1% leading to high incidence of student brawls. Up until now, there is no structured module for CD intervention that can be done by teacher, thus mindfulness therapy is used in scholl to reduce such incidence. The objective of this study is to asses the effectiveness Learning of self-regulation in mindfulness therapy conducted by school counselor inmitigating their involvement in brawls and other forms of violence. Changes in behaviour and cortisol level are used as indicators of success. Met*hod: subject were randomly assigned into treatment as usual (with school counselors) and into Mindfulness training by counselors supervised by a psychiatrist. Cortisol level was checked before and after treatment. Behavioral changes were reported trough a conduct disorder instrument developed for the study. Outcome data was analized using Chi-square, Odd Risk Ratio calculation, and the General Linear Model Repeated Measures. Results and conclusion: 103 students completed the study (intervention n=53 control n=50) after 8 weeks, showing the effectiveness of Mindfulness therapy by NNT=2, RR=3,40 (2,04-5,65. The secondary results showed a decrease of anti-social behaviour measured by TCD-AM and a significant decrease of serum cortisol level (p0,00) compared to the control group. Minfulness therapy recomended to manage anti-social behavior in school. Learning of self-regulation in mindfulness therapy resulted in improvement of emotional and behavioral control among adolescent with conduct disorder. Minfulness therapy can be conducted by school counselors after appropiate training. This study is limited among male adolescents with mild and moderate history of conduct disorder. Girls and the experienced severe conduct disorders were not included in study

Investigating model performance in language identification: beyond simple error statistics

Language development experts need tools that can automatically identify languages from fluent, conversational speech, and provide reliable estimates of usage rates at the level of an individual recording. However, language identification systems are typically evaluated on metrics such as equal error rate and balanced accuracy, applied at the level of an entire speech corpus. These overview metrics do not provide information about model performance at the level of individual speakers, recordings, or units of speech with different linguistic characteristics. Overview statistics may therefore mask systematic errors in model performance for some subsets of the data, and consequently, have worse performance on data derived from some subsets of human speakers, creating a kind of algorithmic bias. In the current paper, we investigate how well a number of language identification systems perform on individual recordings and speech units with different linguistic properties in the MERLIon CCS Challenge. The Challenge dataset features accented English-Mandarin code-switched child-directed speech.Comment: Accepted to Interspeech 2023, 5 pages, 5 figure