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2.
Nat Commun ; 15(1): 3557, 2024 Apr 26.
Article En | MEDLINE | ID: mdl-38670944

Genome-wide association studies (GWAS) have identified more than 200 common genetic variants independently associated with colorectal cancer (CRC) risk, but the causal variants and target genes are mostly unknown. We sought to fine-map all known CRC risk loci using GWAS data from 100,204 cases and 154,587 controls of East Asian and European ancestry. Our stepwise conditional analyses revealed 238 independent association signals of CRC risk, each with a set of credible causal variants (CCVs), of which 28 signals had a single CCV. Our cis-eQTL/mQTL and colocalization analyses using colorectal tissue-specific transcriptome and methylome data separately from 1299 and 321 individuals, along with functional genomic investigation, uncovered 136 putative CRC susceptibility genes, including 56 genes not previously reported. Analyses of single-cell RNA-seq data from colorectal tissues revealed 17 putative CRC susceptibility genes with distinct expression patterns in specific cell types. Analyses of whole exome sequencing data provided additional support for several target genes identified in this study as CRC susceptibility genes. Enrichment analyses of the 136 genes uncover pathways not previously linked to CRC risk. Our study substantially expanded association signals for CRC and provided additional insight into the biological mechanisms underlying CRC development.


Asian People , Colorectal Neoplasms , Genetic Predisposition to Disease , Genome-Wide Association Study , Polymorphism, Single Nucleotide , Quantitative Trait Loci , White People , Humans , Colorectal Neoplasms/genetics , Asian People/genetics , White People/genetics , Exome Sequencing , Case-Control Studies , Transcriptome , Chromosome Mapping , Male , Female , East Asian People
4.
Open Heart ; 11(1)2024 Jan 19.
Article En | MEDLINE | ID: mdl-38242561

OBJECTIVE: Heart failure remains a key public health priority across the globe. The median age of people with heart failure admitted to hospital in the UK is 81 years old. Many such patients transcend the standard interventions that are well characterised and evidenced in guidelines, into holistic aspects surrounding frailty, rehabilitation and social care. Previous published competency frameworks in heart failure have focused on the value of doctors, nurses and pharmacists. We aimed to provide an expert consensus on the minimum heart failure-specific competencies necessary for multiple different healthcare professionals, including physiotherapists, occupational therapists, dietitians and cardiac physiologists. METHODS: The document has been developed focussing on four main parts, (1) establishing a project working group of expert professionals, (2) a literature review of previously existing published curricula and competency frameworks, (3) consensus building, which included developing a structure to the framework with ongoing review of the contents to adapt and be inclusive for each specialty and (4) write up and dissemination to widen the impact of the project. RESULTS: The final competency framework displays competencies across seven sections; knowledge (including subheadings on heart failure syndrome, diagnosis and clinical management); general skills; heart failure-specific skills; clinical autonomy; multidisciplinary team working; teaching and education; and research and development. CONCLUSION: People with heart failure can be complex and have needs that require input from a broad range of specialties. This publication focuses on the vital impact of wider multidisciplinary groups and should help define the generic core heart failure-specific competencies needed to support future pipelines of professionals, who regularly interact with and deliver care for patients with heart failure.


Health Personnel , Heart Failure , Humans , Aged, 80 and over , Health Personnel/education , Curriculum , Heart Failure/diagnosis , Heart Failure/therapy
6.
Respir Med Res ; 83: 101005, 2023 Jun.
Article En | MEDLINE | ID: mdl-37031570

Differences in the diagnostic approach to bronchopulmonary dysplasia (BPD) may contribute to variation in reported BPD rates. We undertook a nationwide survey of UK neonatal units (NNUs) to describe criteria applied by neonatologists to conduct pulse oximetry studies in ex-preterm infants to assess their need for supplemental oxygen near discharge, as well as criteria applied to interpret saturation studies. Responses from 112 (64.7%) NNUs demonstrated wide variation in both criteria used to select infants for assessment and thresholds for interpretation. Neither demonstrated a clear relationship with reported BPD rates. Variation in clinical practice requires further scrutiny to inform and streamline management of ex-preterm infants at risk of BPD, and potentially improve outcomes.


Bronchopulmonary Dysplasia , Infant, Premature , Infant , Infant, Newborn , Humans , Oximetry , Bronchopulmonary Dysplasia/diagnosis , Bronchopulmonary Dysplasia/epidemiology , Bronchopulmonary Dysplasia/therapy , Oxygen , United Kingdom/epidemiology
8.
Plant Physiol ; 191(2): 1084-1101, 2023 02 12.
Article En | MEDLINE | ID: mdl-36508348

Grass inflorescences support floral structures that each bear a single grain, where variation in branch architecture directly impacts yield. The maize (Zea mays) RAMOSA1 (ZmRA1) transcription factor acts as a key regulator of inflorescence development by imposing branch meristem determinacy. Here, we show RA1 transcripts accumulate in boundary domains adjacent to spikelet meristems in sorghum (Sorghum bicolor, Sb) and green millet (Setaria viridis, Sv) inflorescences similar as in the developing maize tassel and ear. To evaluate the functional conservation of syntenic RA1 orthologs and promoter cis sequences in maize, sorghum, and setaria, we utilized interspecies gene transfer and assayed genetic complementation in a common inbred background by quantifying recovery of normal branching in highly ramified ra1-R mutants. A ZmRA1 transgene that includes endogenous upstream and downstream flanking sequences recovered normal tassel and ear branching in ra1-R. Interspecies expression of two transgene variants of the SbRA1 locus, modeled as the entire endogenous tandem duplication or just the nonframeshifted downstream copy, complemented ra1-R branching defects and induced unusual fasciation and branch patterns. The SvRA1 locus lacks conserved, upstream noncoding cis sequences found in maize and sorghum; interspecies expression of a SvRA1 transgene did not or only partially recovered normal inflorescence forms. Driving expression of the SvRA1 coding region by the ZmRA1 upstream region, however, recovered normal inflorescence morphology in ra1-R. These data leveraging interspecies gene transfer suggest that cis-encoded temporal regulation of RA1 expression is a key factor in modulating branch meristem determinacy that ultimately impacts grass inflorescence architecture.


Sorghum , Zea mays , Zea mays/metabolism , Inflorescence/genetics , Inflorescence/metabolism , Plant Proteins/metabolism , Poaceae/genetics , Transcription Factors/metabolism , Sorghum/genetics , Sorghum/metabolism , Meristem/metabolism
9.
Nat Genet ; 55(1): 89-99, 2023 01.
Article En | MEDLINE | ID: mdl-36539618

Colorectal cancer (CRC) is a leading cause of mortality worldwide. We conducted a genome-wide association study meta-analysis of 100,204 CRC cases and 154,587 controls of European and east Asian ancestry, identifying 205 independent risk associations, of which 50 were unreported. We performed integrative genomic, transcriptomic and methylomic analyses across large bowel mucosa and other tissues. Transcriptome- and methylome-wide association studies revealed an additional 53 risk associations. We identified 155 high-confidence effector genes functionally linked to CRC risk, many of which had no previously established role in CRC. These have multiple different functions and specifically indicate that variation in normal colorectal homeostasis, proliferation, cell adhesion, migration, immunity and microbial interactions determines CRC risk. Crosstissue analyses indicated that over a third of effector genes most probably act outside the colonic mucosa. Our findings provide insights into colorectal oncogenesis and highlight potential targets across tissues for new CRC treatment and chemoprevention strategies.


Colorectal Neoplasms , East Asian People , European People , Humans , Colorectal Neoplasms/genetics , East Asian People/genetics , European People/genetics , Genetic Predisposition to Disease , Genome-Wide Association Study , Multiomics , Polymorphism, Single Nucleotide/genetics
11.
BMJ ; 379: e071707, 2022 11 09.
Article En | MEDLINE | ID: mdl-36351667

OBJECTIVE: To evaluate the benefit of combining polygenic risk scores with the QCancer-10 (colorectal cancer) prediction model for non-genetic risk to identify people at highest risk of colorectal cancer. DESIGN: Population based cohort study. SETTING: Data from the UK Biobank study, collected between March 2006 and July 2010. PARTICIPANTS: 434 587 individuals with complete data for genetics and QCancer-10 predictions were included in the QCancer-10 plus polygenic risk score modelling and validation cohorts. MAIN OUTCOME MEASURES: Prediction of colorectal cancer diagnosis by genetic, non-genetic, and combined risk models. Using data from UK Biobank, six different polygenic risk scores for colorectal cancer were developed using LDpred2 polygenic risk score software, clumping, and thresholding approaches, and a model based on genome-wide significant polymorphisms. The top performing genome-wide polygenic risk score and the score containing genome-wide significant polymorphisms were combined with QCancer-10 and performance was compared with QCancer-10 alone. Case-control (logistic regression) and time-to-event (Cox proportional hazards) analyses were used to evaluate risk model performance in men and women. RESULTS: Polygenic risk scores derived using the LDpred2 program performed best, with an odds ratio per standard deviation of 1.584 (95% confidence interval 1.536 to 1.633), and top age and sex adjusted C statistic of 0.733 (95% confidence interval 0.710 to 0.753) in logistic regression models in the validation cohort. Integrated QCancer-10 plus polygenic risk score models out-performed QCancer-10 alone. In men, the integrated LDpred2 model produced a C statistic of 0.730 (0.720 to 0.741) and explained variation of 28.2% (26.3 to 30.1), compared with 0.693 (0.682 to 0.704) and 21.0% (18.9 to 23.1) for QCancer-10 alone. In women, the C statistic for the integrated LDpred2 model was 0.687 (0.673 to 0.702) and explained variation was 21.0% (18.7 to 23.7), compared with 0.645 (0.631 to 0.659) and 12.4% (10.3 to 14.6) for QCancer-10 alone. In the top 20% of individuals at highest absolute risk, the sensitivity and specificity of the integrated LDpred2 models for predicting colorectal cancer diagnosis was 47.8% and 80.3% respectively in men, and 42.7% and 80.1% respectively in women, with increases in absolute risk in the top 5% of risk in men of 3.47-fold and in women of 2.77-fold compared with the median. Illustrative decision curve analysis indicated a small incremental improvement in net benefit with QCancer-10 plus polygenic risk score models compared with QCancer-10 alone. CONCLUSIONS: Integrating polygenic risk scores with QCancer-10 modestly improves risk prediction over use of QCancer-10 alone. Given that QCancer-10 data can be obtained relatively easily from health records, use of polygenic risk score in risk stratified population screening for colorectal cancer currently has no clear justification. The added benefit, cost effectiveness, and acceptability of polygenic risk scores should be carefully evaluated in a real life screening setting before implementation in the general population.


Biological Specimen Banks , Colorectal Neoplasms , Male , Humans , Female , Cohort Studies , Genome-Wide Association Study , Risk Factors , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/epidemiology , Colorectal Neoplasms/genetics , United Kingdom/epidemiology
12.
J Clin Orthop Trauma ; 18: 13-19, 2021 Jul.
Article En | MEDLINE | ID: mdl-33987078

Rotator cuff related disorders (RCRD) are common. Exercise-based rehabilitation can improve outcomes, yet uncertainty exists regarding the characteristics of these exercises. This scoping review paper summarises the key characteristics of the exercise-based rehabilitation of rotator cuff related disorders (RCRD). An iterative search process was used to capture the breadth of current evidence and a narrative summary of the data was produced. 57 papers were included. Disagreement around terminology, diagnostic standards, and outcome measures limits the comparison of the data. Rehabilitation should utilise a biopsychosocial approach, be person-centred and foster self-efficacy. Biomedically framed beliefs can create barriers to rehabilitation. Pain drivers in RCRSD are unclear, as is the influence of pain during exercise on outcomes. Expectations and preferences around pain levels should be discussed to allow the co-creation of a programme that is tolerated and therefore engaged with. The optimal parameters of exercise-based rehabilitation remain unclear; however, programmes should be individualised and progressive, with a minimum duration of 12 weeks. Supervised or home-based exercises are equally effective. Following rotator cuff repair, rehabilitation should be milestone-driven and individualised; communication across the MDT is essential. For individuals with massive rotator cuff tears, the anterior deltoid programme is a useful starting point and should be supplemented by functional rehabilitation, exercises to optimise any remaining cuff and the rest of the kinetic chain. In conclusion, exercise-based rehabilitation improves outcomes for individuals with a range of RCRD. The optimal parameters of these exercises remain unclear. Variation exists across current physiotherapy practice and post-operative rehabilitation protocols, reflecting the wide-ranging spectrum of individuals presenting with RCRD. Clinicians should use their communication and rehabilitation expertise to plan an exercise-based program in conjunction with the individual with RCRSD, which is regularly reviewed and adjusted.

14.
Lancet Oncol ; 21(10): 1309-1316, 2020 10.
Article En | MEDLINE | ID: mdl-32853557

BACKGROUND: Patients with cancer are purported to have poor COVID-19 outcomes. However, cancer is a heterogeneous group of diseases, encompassing a spectrum of tumour subtypes. The aim of this study was to investigate COVID-19 risk according to tumour subtype and patient demographics in patients with cancer in the UK. METHODS: We compared adult patients with cancer enrolled in the UK Coronavirus Cancer Monitoring Project (UKCCMP) cohort between March 18 and May 8, 2020, with a parallel non-COVID-19 UK cancer control population from the UK Office for National Statistics (2017 data). The primary outcome of the study was the effect of primary tumour subtype, age, and sex and on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) prevalence and the case-fatality rate during hospital admission. We analysed the effect of tumour subtype and patient demographics (age and sex) on prevalence and mortality from COVID-19 using univariable and multivariable models. FINDINGS: 319 (30·6%) of 1044 patients in the UKCCMP cohort died, 295 (92·5%) of whom had a cause of death recorded as due to COVID-19. The all-cause case-fatality rate in patients with cancer after SARS-CoV-2 infection was significantly associated with increasing age, rising from 0·10 in patients aged 40-49 years to 0·48 in those aged 80 years and older. Patients with haematological malignancies (leukaemia, lymphoma, and myeloma) had a more severe COVID-19 trajectory compared with patients with solid organ tumours (odds ratio [OR] 1·57, 95% CI 1·15-2·15; p<0·0043). Compared with the rest of the UKCCMP cohort, patients with leukaemia showed a significantly increased case-fatality rate (2·25, 1·13-4·57; p=0·023). After correction for age and sex, patients with haematological malignancies who had recent chemotherapy had an increased risk of death during COVID-19-associated hospital admission (OR 2·09, 95% CI 1·09-4·08; p=0·028). INTERPRETATION: Patients with cancer with different tumour types have differing susceptibility to SARS-CoV-2 infection and COVID-19 phenotypes. We generated individualised risk tables for patients with cancer, considering age, sex, and tumour subtype. Our results could be useful to assist physicians in informed risk-benefit discussions to explain COVID-19 risk and enable an evidenced-based approach to national social isolation policies. FUNDING: University of Birmingham and University of Oxford.


Coronavirus Infections/mortality , Neoplasms/mortality , Pandemics , Pneumonia, Viral/mortality , Adult , Aged , Aged, 80 and over , Betacoronavirus/pathogenicity , COVID-19 , Coronavirus Infections/complications , Coronavirus Infections/pathology , Coronavirus Infections/virology , Female , Hospitalization , Humans , Male , Middle Aged , Neoplasms/pathology , Neoplasms/virology , Pneumonia, Viral/complications , Pneumonia, Viral/pathology , Pneumonia, Viral/virology , Prospective Studies , Risk Assessment , Risk Factors , SARS-CoV-2
15.
Nat Commun ; 10(1): 2154, 2019 05 14.
Article En | MEDLINE | ID: mdl-31089142

Colorectal cancer (CRC) is a leading cause of cancer-related death worldwide, and has a strong heritable basis. We report a genome-wide association analysis of 34,627 CRC cases and 71,379 controls of European ancestry that identifies SNPs at 31 new CRC risk loci. We also identify eight independent risk SNPs at the new and previously reported European CRC loci, and a further nine CRC SNPs at loci previously only identified in Asian populations. We use in situ promoter capture Hi-C (CHi-C), gene expression, and in silico annotation methods to identify likely target genes of CRC SNPs. Whilst these new SNP associations implicate target genes that are enriched for known CRC pathways such as Wnt and BMP, they also highlight novel pathways with no prior links to colorectal tumourigenesis. These findings provide further insight into CRC susceptibility and enhance the prospects of applying genetic risk scores to personalised screening and prevention.


Colorectal Neoplasms/genetics , Genetic Loci , Genetic Predisposition to Disease , Asian People/genetics , Case-Control Studies , Colorectal Neoplasms/pathology , Datasets as Topic , Female , Genome-Wide Association Study , Humans , Inheritance Patterns , Male , Middle Aged , Polymorphism, Single Nucleotide , Risk Factors , White People/genetics
16.
J Natl Cancer Inst ; 111(8): 828-836, 2019 08 01.
Article En | MEDLINE | ID: mdl-30649440

BACKGROUND: Constitutional loss of function (LOF) single nucleotide polymorphisms (SNPs) in pattern recognition receptors FPR1, TLR3, and TLR4 have previously been reported to predict oxaliplatin benefit in colorectal cancer. Confirmation of this association could substantially improve patient stratification. METHODS: We performed a retrospective biomarker analysis of the Short Course in Oncology Therapy (SCOT) and COIN/COIN-B trials. Participant status for LOF variants in FPR1 (rs867228), TLR3 (rs3775291), and TLR4 (rs4986790/rs4986791) was determined by genotyping array or genotype imputation. Associations between LOF variants and disease-free survival (DFS) and overall survival (OS) were analyzed by Cox regression, adjusted for confounders, using additive, dominant, and recessive genetic models. All statistical tests were two-sided. RESULTS: Our validation study populations included 2929 and 1948 patients in the SCOT and COIN/COIN-B cohorts, respectively, of whom 2728 and 1672 patients had functional status of all three SNPs determined. We found no evidence of an association between any SNP and DFS in the SCOT cohort, or with OS in either cohort, irrespective of the type of model used. This included models for which an association was previously reported for rs867228 (recessive model, multivariable-adjusted hazard ratio [HR] for DFS in SCOT = 1.19, 95% confidence interval [CI] = 0.99 to 1.45, P = .07; HR for OS in COIN/COIN-B = 0.92, 95% CI = 0.63 to 1.34, P = .66), and rs4986790 (dominant model, multivariable-adjusted HR for DFS in SCOT = 0.86, 95% CI = 0.65 to 1.13, P = .27; HR for OS in COIN/COIN-B = 1.08, 95% CI = 0.90 to 1.31, P = .40). CONCLUSION: In this prespecified analysis of two large clinical trials, we found no evidence that constitutional LOF SNPs in FPR1, TLR3, or TLR4 are associated with differential benefit from oxaliplatin. Our results suggest these SNPs are unlikely to be clinically useful biomarkers.


Colorectal Neoplasms/drug therapy , Receptors, Formyl Peptide/genetics , Toll-Like Receptor 3/genetics , Toll-Like Receptor 4/genetics , Adult , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers, Tumor/genetics , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Disease-Free Survival , Female , Genotype , Humans , Male , Middle Aged , Oxaliplatin/adverse effects , Oxaliplatin/therapeutic use , Polymorphism, Genetic , Polymorphism, Single Nucleotide/genetics , Receptors, Pattern Recognition/genetics
17.
Curr Genet Med Rep ; 7(2): 63-74, 2019.
Article En | MEDLINE | ID: mdl-32117599

PURPOSE OF REVIEW: As the costs of genomic testing have fallen, and our understanding of genetic susceptibility to cancers has grown, there has been increasing interest in incorporating testing for cancer susceptibility genes, and polygenic risk estimates, into population cancer screening. A growing body of evidence suggests that this would be both clinically and cost-effective. In this article, we aim to explore the frameworks used to evaluate screening programmes, evaluate whether population screening for cancer susceptibility can be assessed using these standards, and consider additional issues and outcomes of importance in this context. RECENT FINDINGS: There are tensions between traditional approaches of genetic testing (utilising tests with high sensitivity and specificity) and the principles of population screening (in which the screening test typically has low specificity), as well as the frameworks used to evaluate the two. Despite the existence of many screening guidelines, including consensus papers, these often do not align fully with broader considerations of genetic test evaluation. Population screening for genetic risk in cancer shifts the focus from diagnostics to prognostication and has wider implications for personal and familial health than existing screening programmes. In addition, understanding of the prevalence and penetrance of cancer susceptibility genes, required by many screening guidelines, may only be obtainable through population-level testing; prospective multi-disciplinary research alongside implementation will be essential. SUMMARY: Appropriate evaluation of genetic screening for cancer risk will require modification of existing screening frameworks to incorporate additional complexity of outcomes and population values. As evidence supporting population screening for cancer susceptibility mounts, development of an appropriate evaluative framework, and expansion of public dialogue will be key to informing policy.

18.
J Parasitol ; 103(6): 653-662, 2017 12.
Article En | MEDLINE | ID: mdl-28891740

Caridean shrimp are critical components of sea-grass communities and occasionally harbor parasitic bopyrid isopods, which can negatively impact their hosts. However, the ecological factors that drive infection rates of parasitic bopyrid isopods in host carideans are poorly known. We examined 43,875 carideans belonging to 6 families and 11 genera from 19 shallow-water localities throughout south Florida. Of these, only 114 shrimp (belonging to 5 genera) were found to be infested with bopyrids (an additional 251 had deformed carapaces consistent with recent infestation). We identified 13 bopyrid species ( Bopyrina abbreviata, Bopyrinella thorii, Eophrixus subcaudalis, Loki circumsaltanus, Metaphrixus carolii, Ovobopyrus alphezemiotes, Parabopyrella lata, Parabopyrella richardsonae, Parabopyriscus stellatus, Capitetragonia alphei, Probopyrus pandalicola, Schizobopyrina urocaridis, and an unidentified Diplophryxus sp.). Bopyrid infection rates were very low throughout the study area, with mean prevalence of 0.26% (range 0.04-1.48%). Furthermore, each isopod species was only ever recovered from a single host genus, suggesting a high degree of genus-level specificity. At the community level, multivariate analyses (RELATE and BVSTEP) indicated that bopyrid community composition was correlated with host community structure, latitude, and temperature, as well as the relative coverage of the sea grasses Thalassia sp. and Syringodium sp. and the alga Penicillus sp. Only 4 parasite taxa were sufficiently abundant to warrant further analysis at the individual taxon level: B. abbreviata, B. thorii, Diplophryxus sp., and P. pandalicola; stepwise regression indicated that bopyrid infection rates were primarily driven by the abundance of their specific hosts, and secondarily by environmental variables such as temperature and depth, as well as algal and sea-grass community composition.


Alismatales/growth & development , Decapoda/parasitology , Hydrocharitaceae/growth & development , Isopoda/physiology , Animals , Atlantic Ocean , Bays , Decapoda/growth & development , Female , Florida , Gulf of Mexico , Host-Parasite Interactions , Lakes , Multivariate Analysis , Nephelometry and Turbidimetry , Regression Analysis , Rivers , Temperature
19.
Plant Cell ; 29(7): 1622-1641, 2017 Jul.
Article En | MEDLINE | ID: mdl-28698237

Leaf architecture directly influences canopy structure, consequentially affecting yield. We discovered a maize (Zea mays) mutant with aberrant leaf architecture, which we named drooping leaf1 (drl1). Pleiotropic mutations in drl1 affect leaf length and width, leaf angle, and internode length and diameter. These phenotypes are enhanced by natural variation at the drl2 enhancer locus, including reduced expression of the drl2-Mo17 allele in the Mo17 inbred. A second drl2 allele, produced by transposon mutagenesis, interacted synergistically with drl1 mutants and reduced drl2 transcript levels. The drl genes are required for proper leaf patterning, development and cell proliferation of leaf support tissues, and for restricting auricle expansion at the midrib. The paralogous loci encode maize CRABS CLAW co-orthologs in the YABBY family of transcriptional regulators. The drl genes are coexpressed in incipient and emergent leaf primordia at the shoot apex, but not in the vegetative meristem or stem. Genome-wide association studies using maize NAM-RIL (nested association mapping-recombinant inbred line) populations indicated that the drl loci reside within quantitative trait locus regions for leaf angle, leaf width, and internode length and identified rare single nucleotide polymorphisms with large phenotypic effects for the latter two traits. This study demonstrates that drl genes control the development of key agronomic traits in maize.


Gene Expression Regulation, Plant , Plant Proteins/genetics , Zea mays/physiology , Base Sequence , Conserved Sequence , Genome-Wide Association Study , Meristem/genetics , Multigene Family , Mutation , Plant Leaves/genetics , Plant Leaves/physiology , Plant Proteins/metabolism , Plant Stems/genetics , Plant Stems/physiology , Quantitative Trait Loci , Zea mays/genetics
20.
Polyhedron ; 114: 299-305, 2016 Aug 16.
Article En | MEDLINE | ID: mdl-27453621

Three new DOTAM (1,4,7,10-tetrakis(acetamido)-1,4,7,10-tetraazacyclododecane) complexes have been synthesized and characterized by X-ray crystallography: [Co(DOTAM)]Cl2•3H2O, [Ni(DOTAM)]Cl2•4H2O, and [Cu(DOTAM)](ClO4)2•H2O. Solid state and solution IR spectroscopic features for a series of [M(DOTAM)]2+ complexes (M=Mn, Co, Cu, Ni, Ca, Zn) correlate with solid state and solution coordination numbers. [Co(DOTAM)]2+, [Ni(DOTAM)]2+, and [Zn(DOTAM)]2+ are demonstrated to be six-coordinate in both the solid state and in solution, while [Mn(DOTAM)]2+ and [Ca(DOTAM)]2+ are eight-coordinate in the solid state and remain so in solution. [Cu(DOTAM)]2+, which is five-coordinate by X-ray crystallography, is shown to increase its coordination number in solution to six-coordinate.

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