Transcriptome analysis of the phosphate starvation response sheds light on strigolactone biosynthesis in rice.

Phosphorus (P) is a major element required for plant growth and development. To cope with P shortage, plants activate local and long-distance signaling pathways, such as an increase in the production and exudation of strigolactones (SLs). The role of the latter in mitigating P deficiency is, however, still largely unknown. To shed light on this, we studied the transcriptional response to P starvation and replenishment in wild-type rice and a SL mutant, dwarf10 (d10), and upon exogenous application of the synthetic SL GR24. P starvation resulted in major transcriptional alterations, such as the upregulation of P TRANSPORTER, SYG1/PHO81/XPR1 (SPX) and VACUOLAR PHOSPHATE EFFLUX TRANSPORTER. Gene Ontology (GO) analysis of the genes induced by P starvation showed enrichment in phospholipid catabolic process and phosphatase activity. In d10, P deficiency induced upregulation of genes enriched for sesquiterpenoid production, secondary shoot formation and metabolic processes, including lactone biosynthesis. Furthermore, several genes induced by GR24 treatment shared the same GO terms with P starvation-induced genes, such as oxidation reduction, heme binding and oxidoreductase activity, hinting at the role that SLs play in the transcriptional reprogramming upon P starvation. Gene co-expression network analysis uncovered a METHYL TRANSFERASE that displayed co-regulation with known rice SL biosynthetic genes. Functional characterization showed that this gene encodes an enzyme catalyzing the conversion of carlactonoic acid to methyl carlactonoate. Our work provides a valuable resource to further studies on the response of crops to P deficiency and reveals a tool for the discovery of SL biosynthetic genes.

Zaxinone Synthase overexpression modulates rice physiology and metabolism, enhancing nutrient uptake, growth and productivity.

The rice Zaxinone Synthase (ZAS) gene encodes a carotenoid cleavage dioxygenase (CCD) that forms the apocarotenoid growth regulator zaxinone in vitro. Here, we generated and characterized constitutive ZAS-overexpressing rice lines, to better understand ZAS role in determining zaxinone content and regulating growth and architecture. ZAS overexpression enhanced endogenous zaxinone level, promoted root growth and increased the number of productive tillers, leading to about 30% higher grain yield per plant. Hormone analysis revealed a decrease in strigolactone (SL) content, which we confirmed by rescuing the high-tillering phenotype through application of a SL analogue. Metabolomics analysis revealed that ZAS overexpressing plants accumulate higher amounts of monosaccharide sugars, in line with transcriptome analysis. Moreover, transgenic plants showed higher carbon (C) assimilation rate and elevated root phosphate, nitrate and sulphate level, enhancing the tolerance towards low phosphate (Pi). Our study confirms ZAS as an important determinant of rice growth and architecture and shows that ZAS regulates hormone homoeostasis and a combination of physiological processes to promote growth and grain yield, which makes this gene an excellent candidate for sustainable crop improvement.

Zaxinone synthase controls arbuscular mycorrhizal colonization level in rice.

The Oryza sativa (rice) carotenoid cleavage dioxygenase OsZAS was described to produce zaxinone, a plant growth-promoting apocarotenoid. A zas mutant line showed reduced arbuscular mycorrhizal (AM) colonization, but the mechanisms underlying this behavior are unknown. Here, we investigated how OsZAS and exogenous zaxinone treatment regulate mycorrhization. Micromolar exogenous supply of zaxinone rescued root growth but not the mycorrhizal defects of the zas mutant, and even reduced mycorrhization in wild-type and zas genotypes. The zas line did not display the increase in the level of strigolactones (SLs) that was observed in wild-type plants at 7 days post-inoculation with AM fungus. Moreover, exogenous treatment with the synthetic SL analog GR24 rescued the zas mutant mycorrhizal phenotype, indicating that the lower AM colonization rate of zas is caused by a deficiency in SLs at the early stages of the interaction, and indicating that during this phase OsZAS activity is required to induce SL production, possibly mediated by the Dwarf14-Like (D14L) signaling pathway. OsZAS is expressed in arbuscule-containing cells, and OsPT11prom::OsZAS transgenic lines, where OsZAS expression is driven by the OsPT11 promoter active in arbusculated cells, exhibit increased mycorrhization compared with the wild type. Overall, our results show that the genetic manipulation of OsZAS activity in planta leads to a different effect on AM symbiosis from that of exogenous zaxinone treatment, and demonstrate that OsZAS influences the extent of AM colonization, acting as a component of a regulatory network that involves SLs.

Whole exome sequencing identifies novel variants of PIK3CA and validation of hotspot mutation by droplet digital PCR in breast cancer among Indian population.

BACKGROUND: Breast cancer (BC) is the most common malignancy with very high incidence and relatively high mortality in women. The PIK3CA gene plays a pivotal role in the pathogenicity of breast cancer. Despite this, the mutational status of all exons except exons 9 and 20 still remains unknown. METHODS: This study uses the whole exome sequencing (WES) based approach to identify somatic PIK3CA mutations in Indian BC cohorts. The resultant hotspot mutations were validated by droplet digital PCR (ddPCR). Further, molecular dynamics (MD) simulation was applied to elucidate the conformational and functional effects of hotspot position on PIK3CA protein. RESULTS: In our cohort, PIK3CA showed a 44.4% somatic mutation rate and was among the top mutated genes. The mutations of PIK3CA were confined in Exons 5, 9, 11, 18, and 20, whereas the maximum number of mutations lies within exons 9 and 20. A total of 9 variants were found in our study, of which 2 were novel mutations observed on exons 9 (p.H554L) and 11 (p.S629P). However, H1047R was the hotspot mutation at exon 20 (20%). In tumor tissues, there was a considerable difference between copy number of wild-type and H1047R mutant was detected by ddPCR. Significant structural and conformational changes were observed during MD simulation, induced due to point mutation at H1047R/L position. CONCLUSIONS: The current study provides a comprehensive view of novel as well as reported single nucleotide variants (SNVs) in PIK3CA gene associated with Indian breast cancer cases. The mutation status of H1047R/L could serve as a prognostic value in terms of selecting targeted therapy in BC.

Primary Epiploic Appendagitis: A Mimicker of Abdominal Pain.

Epiploic appendagitis is a rare cause of acute lower abdominal pain. Epiploic appendices are fat-filled serosal outpouchings of the cecum and sigmoid colon. Primary epiploic appendagitis (PEA) is characterized by epiploic inflammation caused by torsion of the appendage leading to ischemia or thrombosis of the appendage draining vein. Secondary epiploic appendagitis occurs in association with other inflammatory conditions of the abdomen or pelvis, most commonly diverticulitis. PEA is an important clinical mimicker of more severe causes of acute abdominal pain, such as diverticulitis, appendicitis, or gynaecological causes. The ease of access to computed tomography (CT), the diagnostic test of choice, has resulted in increased recognition of PEA. The classic CT findings of PEA are an ovoid mass measuring between 1.5 and 3.5 cm surrounded by a hyperattenuating/hyperdense ring with a centrally located hyperdense area. It is important to diagnose PEA as it is self-limiting and the correct diagnosis can prevent unnecessary hospital admission, antibiotic use, or even surgical intervention. We present a case of a 65-year-old male with a history of diverticulitis, presenting with left lower quadrant abdominal pain who was diagnosed with PEA based on CT and successfully managed with conservative treatment.

A Comparative Analysis on the Innate Immune Responses of Cirrhinus mrigala Challenged with Pseudomonas aeruginosa and Fusarium oxysporum.

Microbes are the most significant ubiquitous pathogens that cause serious infections in freshwater fish, leading to tremendous economic losses. The present study was designed to investigate the extent of changes in cytokine expression, hemato-biochemical parameters, and tissue histology of Cirrhinus mrigala (C. mrigala) challenged with Pseudomonas aeruginosa (P. aeruginosa) and Fusarium oxysporum (F. oxysporum). Fish were divided into three major groups: control, P. aeruginosa-challenged, and F. oxysporum-challenged. The infection in both challenge assays was allowed to progress until 7 days post infection. Upregulated expression of TNF-α and IL-1ß was found in blood, gills, livers, and kidneys of the challenged fish. Significant differences were noted in hematological parameters of challenged fish. Alanine aminotransferase, aspartate aminotransferase, and alkaline aminotransferase levels also showed significant differences in infected and control groups. An increase in serum albumin and globulin and a decrease in total protein were noted in infected groups as compared to the control group. Severe histological alterations were noted in gill, liver, and kidney tissues of the infected groups as compared to control. The order of histological alteration index for P. aeruginosa challenge was liver > kidney > gills, and for F. oxysporum challenge it was kidney > liver > gills. These changes in fish infected by P. aeruginosa and F. oxysporum can be used as an effective and subtle index to monitor the physiological and pathological conditions of fish.

Sociodemographic Characteristics and Patterns of Suicide in Pakistan: An Analysis of Current Trends.

Suicide is a global phenomenon with about 79% of suicides occurring in low and middle-income countries. This study investigated current trends, demographics, and characteristics of completed suicides based on reports from leading Pakistani Newspapers. This study performed a qualitative analysis of completed suicides in Pakistan's four newspapers from January 1st, 2019, through December 31st, 2020. Data about socio-demographic characteristics, methods of suicide, possible motives, and associated features were analyzed. 2295 suicides were reported in Pakistan during 2019 and 2020. About 61.87% were completed by men, and 38.12% by women. The most suicides occurred in individuals ages < 30 years. The predominant method of suicide in this group was ingestion of poisonous substances. The most commonly reported reasons for suicide were domestic conflicts, financial problems, and failure in love/marriage. By providing insight into characteristics of suicide, this study highlights the need for effective suicide prevention policies and programs to tackle rising rates of suicide in Pakistan.

Pattern of Adolescent Suicides in Pakistan: A content analysis of Newspaper reports of two years.

Background and Objective: Suicide is a serious, yet preventable global mental health problem for people of all ages and countries. It is the third leading cause of death in 15-19-year-olds. There is paucity of systematic studies and official statistics on child & adolescent suicides in Pakistan. In the absence of other means, newspaper coverage of adolescent suicides may serve as a useful source to understand the phenomena. Our objective was to report pattern of suicide deaths in children and adolescents across Pakistan and to determine the predominant methods of suicide precipitating events and associated factors. Methods: This study used content analysis to analyze newspaper reports of adolescent suicide in four leading newspapers of Pakistan from January 1st, 2019, through December 31st, 2020. Search yielded 289 child and adolescent (ages<18) suicide reports. Data about various sociodemographic characteristics, methods of suicide, possible motives, and associated features (e.g., any suicide notes) was extracted and analyzed. Results: Total 289 suicides in children and adolescents in Pakistan were reported in selected newspapers during two years among both genders (51.5 % boys and 48.5% girls) with high incidence in late adolescence (66%). The predominant method of suicide in this group was ingestion of poisonous substances (50%) followed by hanging (35%) and use of firearms (7%). The behavior usually takes place within or near the adolescent's home environment. The act was often attributed to domestic conflicts including arguments with parents of the deceased and relationship problems. Conclusion: To develop effective suicide prevention strategies for a population, it must be studied within its own socio-cultural context. Study results emphasize adolescent suicide being a reality in Pakistan. There is urgent need for further culture specific research in this area in the country.

SeedQuant: a deep learning-based tool for assessing stimulant and inhibitor activity on root parasitic seeds.

Witchweeds (Striga spp.) and broomrapes (Orobanchaceae and Phelipanche spp.) are root parasitic plants that infest many crops in warm and temperate zones, causing enormous yield losses and endangering global food security. Seeds of these obligate parasites require rhizospheric, host-released stimulants to germinate, which opens up possibilities for controlling them by applying specific germination inhibitors or synthetic stimulants that induce lethal germination in the host's absence. To determine their effect on germination, root exudates or synthetic stimulants/inhibitors are usually applied to parasitic seeds in in vitro bioassays, followed by assessment of germination ratios. Although these protocols are very sensitive, the germination recording process is laborious, representing a challenge for researchers and impeding high-throughput screens. Here, we developed an automatic seed census tool to count and discriminate germinated seeds (GS) from non-GS. We combined deep learning, a powerful data-driven framework that can accelerate the procedure and increase its accuracy, for object detection with computer vision latest development based on the Faster Region-based Convolutional Neural Network algorithm. Our method showed an accuracy of 94% in counting seeds of Striga hermonthica and reduced the required time from approximately 5 min to 5 s per image. Our proposed software, SeedQuant, will be of great help for seed germination bioassays and enable high-throughput screening for germination stimulants/inhibitors. SeedQuant is an open-source software that can be further trained to count different types of seeds for research purposes.

Application of the Multi-Process Action Control Model to Predict Physical Activity During Late Adolescence.

The aim of this study was to apply the Multi-Process Action Control model to examine how the additions of regulatory and reflexive processes predict physical activity (PA) behaviors among adolescents. Our sample included 1,176 Grade 11 students (Mage = 15.85 ± 0.38) recruited from a large school board in Southern Ontario. Participants completed a questionnaire including measures of self-reported PA and PA cognitions derived from the Multi-Process Action Control model. Results found the reflective process explaining 16.5% of the variance in PA, with the additions of regulatory and reflexive processes significantly improving the explained variance by 5.1% and 8.2%, respectively. Final models revealed coping planning (estimate = 45.10, p = .047), identity (estimate = 55.82, p < .001), and habit (estimate = 64.07, p < .001) as significant predictors of PA. Findings reinforce the need for integrative models to better understand PA, with coping planning, habit formation, and development of an active identity to be salient targets for intervention during adolescence.

A study to evaluate the impact of COVID-19 on Lifestyle of Medical students.

Background: Stressful situations are often linked with poor health and lifestyle behaviors (e.g., unhealthy diet, limited physical activity, poor sleep quality etc.). Subsequent to the nationwide lockdown in Pakistan due to COVID-19 pandemic, medical students experienced substantial lifestyle changes along with academic stresses. The goal of this study was to measure the impact that the COVID-19 lockdown had on lifestyle like sleep, physical activity and nutrition, substance abuse, dealing with finances, spirituality and family life, with respect to a sample of Pakistani medical students. Methods: This cross- sectional online study involving 1100 medical students (68.7% females) from five medical colleges in Pakistan, used self-administered questionnaire to evaluate the impact of pandemic related restrictions on lifestyle of medical students in Pakistan from August- September 2020. Parameters such as physical activity, sleep, nutrition, smoking and substance abuse, family life, finances, internet use and spirituality were studied. Results: Fifty-nine percent of medical students reported a significant effect of lockdown on their physical activity. Only 5.8% people clearly followed or adhered to a routine during the pandemic. About 54.6% students have found that physical activity and exercise significantly reduced their anxiety. More than half of respondents reported increase in screen time, weight gain and poor sleep with 3.1% of students stating an increased use of sleeping pills to fall asleep Another 18.3% students had an increased worry regarding COVID19 based on the information they received on internet. No significant increase in substance uses and alcohol use or family conflicts among students post pandemic was noted. Conclusion: Our findings underscore that COVID-19 pandemic has led to undesired changes in health and lifestyle habits of medical students, which may, to some extent, be responsible for higher negative impact. Hence it is important for medical colleges to start awareness campaigns to tackle challenges for medical students physical and emotional well-being.

SAlign-a structure aware method for global PPI network alignment.

BACKGROUND: High throughput experiments have generated a significantly large amount of protein interaction data, which is being used to study protein networks. Studying complete protein networks can reveal more insight about healthy/disease states than studying proteins in isolation. Similarly, a comparative study of protein-protein interaction (PPI) networks of different species reveals important insights which may help in disease analysis and drug design. The study of PPI network alignment can also helps in understanding the different biological systems of different species. It can also be used in transfer of knowledge across different species. Different aligners have been introduced in the last decade but developing an accurate and scalable global alignment algorithm that can ensures the biological significance alignment is still challenging. RESULTS: This paper presents a novel global pairwise network alignment algorithm, SAlign, which uses topological and biological information in the alignment process. The proposed algorithm incorporates sequence and structural information for computing biological scores, whereas previous algorithms only use sequence information. The alignment based on the proposed technique shows that the combined effect of structure and sequence results in significantly better pairwise alignments. We have compared SAlign with state-of-art algorithms on the basis of semantic similarity of alignment and the number of aligned nodes on multiple PPI network pairs. The results of SAlign on the network pairs which have high percentage of proteins with available structure are 3-63% semantically better than all existing techniques. Furthermore, it also aligns 5-14% more nodes of these network pairs as compared to existing aligners. The results of SAlign on other PPI network pairs are comparable or better than all existing techniques. We also introduce [Formula: see text], a Monte Carlo based alignment algorithm, that produces multiple network alignments with similar semantic similarity. This helps the user to pick biologically meaningful alignments. CONCLUSION: The proposed algorithm has the ability to find the alignments that are more biologically significant/relevant as compared to the alignments of existing aligners. Furthermore, the proposed method is able to generate alternate alignments that help in studying different genes/proteins of the specie.

Structural basis for specific inhibition of the highly sensitive ShHTL7 receptor.

Striga hermonthica is a root parasitic plant that infests cereals, decimating yields, particularly in sub-Saharan Africa. For germination, Striga seeds require host-released strigolactones that are perceived by the family of HYPOSENSITIVE to LIGHT (ShHTL) receptors. Inhibiting seed germination would thus be a promising approach for combating Striga However, there are currently no strigolactone antagonists that specifically block ShHTLs and do not bind to DWARF14, the homologous strigolactone receptor of the host. Here, we show that the octyl phenol ethoxylate Triton X-100 inhibits S. hermonthica seed germination without affecting host plants. High-resolution X-ray structures reveal that Triton X-100 specifically plugs the catalytic pocket of ShHTL7. ShHTL7-specific inhibition by Triton X-100 demonstrates the dominant role of this particular ShHTL receptor for Striga germination. Our structural analysis provides a rationale for the broad specificity and high sensitivity of ShHTL7, and reveals that strigolactones trigger structural changes in ShHTL7 that are required for downstream signaling. Our findings identify Triton and the related 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]acetic acid as promising lead compounds for the rational design of efficient Striga-specific herbicides.

Impact of the COVID-19 Pandemic on Adult Mental Health.

The outbreak of the Novel Coronavirus (COVID-19) in December 2019 has progressed to the status of a global pandemic, with countries across the seven continents adversely affected and the number of human cases exceeding two million. With no available vaccine, the treatment is primarily symptomatic for those affected and preventative for those at risk. Most countries have taken action to curtail the spread of COVID-19 through measures such as lockdowns, social distancing and voluntary self-isolation. Whilst necessary, such measures and the disease itself, may have an adverse impact on mental health. In view of research from previous pandemic crises, it is known that such situations are likely to increase stress levels and have negative psychiatric effects. The impact is likely to be felt by the general public, sufferers of COVID-19, their families and friends, persons with pre-existing mental health conditions and healthcare workers.

Assessment of Psycho-Education of Carers Questionnaire: APEC-U" translation and cross cultural adaptation of an Urdu Version.

BACKGROUND AND OBJECTIVE: Psycho-education of carers is a part of good mental health practice. Our objective was to translate and validate the English questionnaire "Assessment of Psycho-Education of Carers" (APEC) into Urdu (APEC-U), for use in Pakistan. METHODS: Following development and validation of APEC, it was translated into Urdu after consultation with experts and translators. After pretesting, one hundred and twenty bilingual male 67(55.8%) and female 53(44.2%) primary carers, who could understand both Urdu and English, and were carers for more than three months, were asked to fill in the self reporting Urdu questionnaire at the Fatima Memorial Hospital Psychiatry Out-Patient Department. The data were collected over a period of three months from September, 2018 to November, 2018. MAIN OUTCOME MEASURES: Responses were analyzed for internal consistency, reliability, Intraclass correlation coefficients and kappa statistics. RESULTS: APEC-U was understandable and capable of assessing psycho-education in Urdu. High internal consistency was demonstrated on the full scale as 0.859. Degree of agreement (<0.001) between the Urdu and the originally developed English version was evaluated by Cohen's Kappa, and a high degree of agreement was demonstrated. CONCLUSION: The Urdu questionnaire can adequately assess psycho-education of carers in psychiatric settings.

The interaction of strigolactones with abscisic acid during the drought response in rice.

Both strigolactones (SLs) and abscisic acid (ABA) biosynthetically originate from carotenoids. Considering their common origin, the interaction of these two hormones at the biosynthetic and/or regulatory level may be anticipated. Here we show that, in rice, drought simultaneously induces SL production in the root, and ABA production and the expression of SL biosynthetic genes in the shoot. Under control conditions, the ABA concentration was higher in shoots of the SL biosynthetic rice mutants dwarf10 (d10) and d17 than in wild-type plants, while a similar trend was observed for the SL perception mutant d3. These differences were enhanced under drought. However, drought did not result in an increase in leaf ABA content in the rice mutant line d27, carrying a mutation in the gene encoding the first committed enzyme in SL biosynthesis, to the same extent as in the other SL mutants and the wild type. Accordingly, d10, d17, and d3 lines were more drought tolerant than wild-type plants, whereas d27 displayed decreased tolerance. Finally, overexpression of OsD27 in rice resulted in increased levels of ABA when compared with wild-type plants. We conclude that the SL and ABA pathways are connected with each other through D27, which plays a crucial role in determining ABA and SL content in rice.

Methyl phenlactonoates are efficient strigolactone analogs with simple structure.

Strigolactones (SLs) are a new class of phytohormones that also act as germination stimulants for root parasitic plants, such as Striga spp., and as branching factors for symbiotic arbuscular mycorrhizal fungi. Sources for natural SLs are very limited. Hence, efficient and simple SL analogs are needed for elucidating SL-related biological processes as well as for agricultural applications. Based on the structure of the non-canonical SL methyl carlactonoate, we developed a new, easy to synthesize series of analogs, termed methyl phenlactonoates (MPs), evaluated their efficacy in exerting different SL functions, and determined their affinity for SL receptors from rice and Striga hermonthica. Most of the MPs showed considerable activity in regulating plant architecture, triggering leaf senescence, and inducing parasitic seed germination. Moreover, some MPs outperformed GR24, a widely used SL analog with a complex structure, in exerting particular SL functions, such as modulating Arabidopsis roots architecture and inhibiting rice tillering. Thus, MPs will help in elucidating the functions of SLs and are promising candidates for agricultural applications. Moreover, MPs demonstrate that slight structural modifications clearly impact the efficiency in exerting particular SL functions, indicating that structural diversity of natural SLs may mirror a functional specificity.

Development and validation of assessment of psycho-education of carers questionnaire: An early experience.

BACKGROUND AND OBJECTIVE: Psycho-education is an intervention integrating psychotherapeutic and educational strategies. Whilst carer psycho-education is known to aid in psychiatric disorders, at present there is no known tool to assess the degree to which this is routinely provided by mental health professionals. Our objective was to develop and validate a tool, in English, which assesses psycho-education of carers of psychiatric patients in Pakistan. METHODS: A questionnaire was generated in English. It was pretested on twenty male and female carers and was refined to attain a more reliable version. Sixty bilingual male and female primary carers, who were fluent in English, and had been in a care-giving role for more than three months were requested to complete the developed Questionnaire for the Assessment of Psycho-Education of Carers (APEC) at Fatima Memorial Hospital Psychiatry Out-patient department within a period of four months from December, 2017 to April, 2018. Carers were identified via patients presenting to a psychiatric OPD. Responses were analyzed for reliability and test retest consistency using Cronbach's alpha analysis, Intraclass correlation coefficients, factor analysis and Paired t-test. RESULTS: APEC was found to be easily understandable and capable of adequately assessing aspects of psycho-education. A high degree of internal consistency was demonstrated on cronbach's alpha analysis. Cronbach's α coefficient for various domains was sufficiently high ranging from0.76 to 0.960. Similarly, domains of (APEC) were highly correlated. Test-retest reliability was assessed by computing the correlation between Visits 1 and 2 scores. CONCLUSION: The developed questionnaire can adequately assess psycho-education of primary carers in mental health settings.

Volumetric Single-Beat Coronary Computed Tomography Angiography: Relationship of Image Quality, Heart Rate, and Body Mass Index. Initial Patient Experience With a New Computed Tomography Scanner.

BACKGROUND: Cardiac computed tomography (CT) image quality (IQ) is very important for accurate diagnosis. We propose to evaluate IQ expressed as Likert scale, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) from coronary CT angiography images acquired with a new volumetric single-beat CT scanner on consecutive patients and assess the IQ dependence on heart rate (HR) and body mass index (BMI). METHODS: We retrospectively analyzed the data of the first 439 consecutive patients (mean age, 55.13 [SD, 12.1] years; 51.47% male), who underwent noninvasive coronary CT angiography in a new single-beat volumetric CT scanner (Revolution CT) to evaluate chest pain at West Kendall Baptist Hospital. Based on patient BMI (mean, 29.43 [SD, 5.81] kg/m), the kVp (kilovolt potential) value and tube current were adjusted within a range of 80 to 140 kVp and 122 to 720 mA, respectively. Each scan was performed in a single-beat acquisition within 1 cardiac cycle, regardless of the HR. Motion correction software (SnapShot Freeze) was used for correcting motion artifacts in patients with higher HRs. Autogating was used to automatically acquire systolic and diastolic phases for higher HRs with electrocardiographic milliampere dose modulation. Image quality was assessed qualitatively by Likert scale and quantitatively by SNR and CNR for the 4 major vessels right coronary, left main, left anterior descending, and left circumflex arteries on axial and multiplanar reformatted images. Values for Likert scale were as follows: 1, nondiagnostic; 2, poor; 3, good; 4, very good; and 5, excellent. Signal-to-noise ratio and CNR were calculated from the average 2 CT attenuation values within regions of interest placed in the proximal left main and proximal right coronary artery. For contrast comparison, a region of interest was selected from left ventricular wall at midcavity level using a dedicated workstation. We divided patients in 2 groups related to the HR: less than or equal to 70 beats/min (bpm) and greater than 70 bpm and also analyzed them in 2 BMI groupings: BMI less than or equal to 30 kg/m and BMI greater than 30 kg/m. RESULTS: Mean SNR was 8.7 (SD, 3.1) (n = 349) for group with HR 70 bpm or less and 7.7 (SD, 2.4) (n = 78) for group with HR greater than 70 bpm (P = 0.008). Mean CNR was 6.9 (SD, 2.7) (n = 349) for group with HR 70 bpm or less and 5.9 (SD, 2.2) (n = 78) for group with HR 70 bpm or greater (P = 0.002). Mean SNR was 8.8 (SD, 3.2) (n = 249) for group with BMI 30 kg/m or less and 8.1 (SD, 2.6) (n = 176) for group with BMI greater than 30 kg/m (P = 0.008). Mean CNR was 7.0 (SD, 2.8) (n = 249) for group with BMI 30 kg/m or less and 6.4 (SD, 2.4) (n = 176) for group with BMI greater than 30 kg/m (P = 0.002). The results for mean Likert scale values were statistically different, reflecting difference in IQ between people with HR 70 bpm or less and greater than 70 bpm, BMI 30 kg/m or less, and BMI greater than 30 kg/m.