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1.
BMC Genomics ; 24(1): 572, 2023 Sep 26.
Article in English | MEDLINE | ID: mdl-37752451

ABSTRACT

BACKGROUND: Telomeres are the nucleoprotein complexes that physically cap the ends of eukaryotic chromosomes. Most plants possess Arabidopsis-type telomere sequences (TSs). In addition to terminal TSs, more diverse interstitial TSs exists in plants. Although telomeres have been sufficiently studied, the actual diversity of TSs in land plants is underestimated. RESULTS: We investigate genotypes from seven natural populations with contrasting environments of four Chenopodium species to reveal the variability in TSs by analyzing Oxford Nanopore reads. Fluorescent in situ hybridization was used to localize telomeric repeats on chromosomes. We identified a number of derivative monomers that arise in part of both terminal and interstitial telomeric arrays of a single genotype. The former presents a case of block-organized double-monomer telomers, where blocks of Arabidopsis-type TTTAGGG motifs were interspersed with blocks of derivative TTTAAAA motifs. The latter is an integral part of the satellitome with transformations specific to the inactive genome fraction. CONCLUSIONS: We suggested two alternative models for the possible formation of derivative monomers from telomeric heptamer motifs of Arabidopsis-type. It was assumed that derivatization of TSs is a ubiquitous process in the plant genome but occurrence and frequencies of derivatives may be genotype-specific. We also propose that the formation of non-canonical arrays of TSs, especially at chromosomal termini, may be a source for genomic variability in nature.


Subject(s)
Arabidopsis , Humans , Arabidopsis/genetics , In Situ Hybridization, Fluorescence , Telomere/genetics , Genotype , Eukaryota
2.
Med Ref Serv Q ; 42(2): 108-124, 2023.
Article in English | MEDLINE | ID: mdl-37104265

ABSTRACT

Due to the rapid growth of information technology and medical information resources, medical personnel need to search and retrieve valid and updated information. However, with limited time to access these resources, there is a need for clinical librarians to connect medical staff to evidence-based medicine (EBM). The present study was conducted to identify the challenges in the absence and the benefits of the presence of clinical librarians in the application of EBM in clinical departments. Ten clinical physicians working at Children's Medical Center Hospital in Tehran, Iran were interviewed for this qualitative study. Most of the hospital-based physicians did not make any systematic use of EBM and seven were not familiar with the term "clinical librarian." In their opinion, the clinical librarians' activities included training the clinical and research teams, providing them with the required information, and providing an EBM-oriented approach to morning report and educational rounds. Therefore, the services delivered by clinical librarians in various hospital departments might positively influence the hospital-based physicians' information-seeking behavior.


Subject(s)
Librarians , Child , Humans , Professional Role , Iran , Curriculum , Evidence-Based Medicine/education
3.
J Res Med Sci ; 24: 59, 2019.
Article in English | MEDLINE | ID: mdl-31523245

ABSTRACT

BACKGROUND: Sleep is essential in maintaining health and quality of life. Inflammatory bowel disease (IBD) patients suffer from poor sleep quality. This study aimed to investigate the prevalence of sleep disturbances in Iranian IBD patients as well as the variables which can be attributed to the quality of sleep in IBD patients. MATERIALS AND METHODS: Seventy-one patients filled in Pittsburg Sleep Quality Index (PSQI) questionnaire and a sociodemographic questionnaire. Disease activity was assessed by Crohn's Disease (CD) Activity Index and Ulcerative Colitis (UC) Activity Index. Regression analysis was used to identify the association between sociodemographic and disease characteristics with sleep quality. RESULTS: We found that 32.4% of all patients, 23.1% of patients with "in remission to mild" disease, and 66.7% of patients with "moderate" disease, had poor sleep quality. CD patients were more likely to have poor sleep quality comparing UC ones in crude (odds ratio [OR] =2.14; 95% confidence interval [CI] 1.14-4.04) and adjusted (OR = 6.19; 95% CI 1.13, 34.07) models. Patients with good quality of sleep had lower systolic blood pressure and diastolic blood pressure (P = 0.09 and 0.035 respectively). CONCLUSION: Notable percentage of IBD patients suffer from poor sleep quality even in the remission phase. Treatment of sleep disturbances, especially in CD patients, is recommended in the IBD patient-care program.

4.
Mol Phylogenet Evol ; 129: 189-201, 2018 12.
Article in English | MEDLINE | ID: mdl-30172008

ABSTRACT

Hybridization and polyploidization represent an important speciation mechanism in the diploid-polyploid complex of the Chenopodium album aggregate. In the present study we successfully reconstructed the evolutionary histories of the majority of Eurasian representatives of the C. album aggregate, resulting in the most comprehensive phylogenetic analysis of this taxonomically intricate group of species to date. We applied a combination of classical karyology for precise chromosome number determination, genomic in-situ hybridization for the determination of genomic composition, flow cytometry for the estimation of genome size and sequencing of plastid (cpDNA) and nuclear (ribosomal internal transcribed spacer - ITS and the introns of the FLOWERING LOCUS T LIKE genes - FTL) markers for a phylogenetic reconstruction and the identification of parental genomes in polyploid taxa. The FTL markers identified eight well supported evolutionary lineages. Five of them include at least one diploid species, and the remaining three comprise solely the subgenomes of polyploids that probably represent extinct or unknown diploid taxa. The existence of eight basic diploid lineages explains the origin of seven Eurasian polyploid groups and brings evidence of a nearly unlimited number of subgenomic combinations. The supposed promiscuity generated new species wherever different diploid lineages met each other and gave rise to tetraploid species or whenever they met other tetraploid species to produce hexaploid species throughout their evolutionary history. Finally, we unravelled a surprisingly simple scheme of polyploid species formation within the C. album aggregate. We determined seven groups of polyploid species differing in their origin in either Eurasia or Africa and convincingly demonstrated that (1) all Chenopodium polyploid species under study are of allopolyploid origin, (2) there are eight major monophyletic evolutionary lineages represented by extant or extinct/unknown diploid taxa, (3) those monophyletic lineages represent individual subgenomes, (4) hybridization among the lineages created seven subgenomic combinations of polyploid taxa, (5) taxa represented by particular subgenome combinations were further subjected to diversification, and (6) the majority of species are relatively young, not exceeding the age of the Quaternary period.


Subject(s)
Chenopodium album/cytology , Chenopodium album/genetics , Hybridization, Genetic , Polyploidy , Base Sequence , Chromosomes, Plant/genetics , Evolution, Molecular , Genetic Loci , Genetic Markers , Genome Size , Phylogeny , Tetraploidy
5.
J Res Med Sci ; 22: 104, 2017.
Article in English | MEDLINE | ID: mdl-29026420

ABSTRACT

BACKGROUND: Inflammatory bowel disease (IBD) has a significant impact on health-related quality of life (HRQOL). This study aims to investigate the variables which can be attributed to HRQOL in IBD patients. MATERIALS AND METHODS: Seventy-one patients filled in IBD questionnaire (IBDQ-32), Pittsburgh sleep quality index questionnaire, and sociodemographic questionnaire. Disease activity was assessed by Crohn's disease activity index (CDAI) and ulcerative colitis activity index (UCAI). The correlations of sleep quality, sociodemographic variables, and disease characteristics with IBDQ were investigated. RESULTS: IBDQ-32 mean score was lower in patients who had hospitalization (P = 0.01), poor sleep quality (P < 0.001), anemia (P = 0.03), more severe disease (P = 0.01), and those who had not consumed folic acid (P = 0.01) relative to their counterparts. A multivariate regression analysis identified the predictors of decreased HRQOL as not consuming folic acid (P = 0.008), poor sleep quality (P = 0.014), and disease severity (P = 0.043). CONCLUSION: Impaired HRQOL was significantly associated with poor sleep quality, lack of folic acid consumption, and disease severity in IBD patients. Therefore, evaluation of folic acid level and efficacy of its supplementation in prospective studies is recommended. Treatment of sleep disturbance with pharmacological agents and nonpharmacological methods should be kept in mind as well.

6.
J Pain Symptom Manage ; 50(3): 387-393.e1, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25980966

ABSTRACT

CONTEXT: Various symptoms frequently affect cancer patients' quality of life. Appropriate assessment of these symptoms provides valuable data for cancer management. OBJECTIVES: This study aimed to validate the Persian version of the M. D. Anderson Symptom Inventory (MDASI-P). METHODS: This cross-sectional study was conducted at four cancer treatment centers in two cities in Iran. Breast cancer and colorectal cancer patients aged 18 years and older were consecutively included in the study. The standard forward-backward translation method was applied. Patients completed the MDASI-P along with the previously validated Persian version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30). Construct validity (factor analysis), criterion validity (against the EORTC QLQ-C30), and reliability (Cronbach's alpha) were analyzed. RESULTS: A total of 146 breast cancer and 94 colorectal cancer patients were studied. Factor analysis for the symptom severity items resulted in a three-factor solution, further reduced to a two-factor solution: general symptoms and gastrointestinal symptoms. Correlation of the MDASI-P symptom severity items with corresponding EORTC QLQ-C30 symptom items (r = 0.48-0.75) and MDASI-P interference items with corresponding EORTC QLQ-C30 functioning domains (r = -0.46 to -0.23) supported the criterion validity. Cronbach's alpha was 0.90, 0.88, and 0.77 for the total questionnaire, symptom severity items, and the interference subscale, respectively. CONCLUSION: The MDASI-P is a feasible, valid, and reliable instrument for evaluation of symptoms in Persian-speaking cancer patients and can be used to improve symptom management in these patients.


Subject(s)
Adenocarcinoma/diagnosis , Breast Neoplasms/diagnosis , Colorectal Neoplasms/diagnosis , Linguistics , Severity of Illness Index , Adenocarcinoma/physiopathology , Adenocarcinoma/psychology , Adenocarcinoma/therapy , Breast Neoplasms/physiopathology , Breast Neoplasms/psychology , Breast Neoplasms/therapy , Colorectal Neoplasms/physiopathology , Colorectal Neoplasms/psychology , Colorectal Neoplasms/therapy , Cross-Sectional Studies , Feasibility Studies , Female , Humans , Iran , Male , Middle Aged , Pilot Projects , Psychometrics , Reproducibility of Results , Translations
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