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1.
J Urol ; 204(4): 660, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32648804
2.
J Urol ; 204(4): 649-660, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32105187

RESUMO

PURPOSE: Studies exploring the association of cigarette smoking and long-term survival outcomes following radical cystectomy have yielded mixed results. We performed a systematic review and meta-analysis to investigate the impact of tobacco smoking exposure, duration, intensity and cessation on response to neoadjuvant chemotherapy and long-term survival outcomes in patients undergoing radical cystectomy for bladder cancer. MATERIALS AND METHODS: We systematically searched PubMed®, MEDLINE®, Embase® and Cochrane® Library databases for original articles published before April 2019. Primary end points were neoadjuvant chemotherapy response, overall and cancer specific mortality, and recurrence-free survival after radical cystectomy. Observational studies reporting Cox proportional hazards regression or logistic regression analysis were independently screened. Available multivariable hazard ratios and corresponding 95% CIs were included in the quantitative analysis. Sensitivity analyses were performed as appropriate. A risk of bias assessment was completed for nonrandomized studies. RESULTS: Our electronic search identified a total of 649 articles. After a detailed review we selected 17 studies that addressed the impact of smoking status on survival outcomes in 13,777 patients after radical cystectomy for bladder cancer. Pooled meta-analysis revealed that active smokers have an increased risk of overall mortality (HR 1.21, 95% CI 1.08-1.36; p=0.001, I2=0%), cancer specific mortality (HR 1.24, 95% CI 1.13-1.36; p <0.00001, I2=0%) and bladder cancer recurrence (HR 1.24, 95% CI 1.12-1.38; p <0.0001, I2=3%). Sensitivity analyses evaluating only patients who underwent neoadjuvant chemotherapy followed by radical cystectomy showed an advantage of non/never smokers in terms of neoadjuvant chemotherapy complete response rate (HR 0.47, 95% CI 0.29-0.75; p=0.001, I2=0%). CONCLUSIONS: Smoking status is associated with lower neoadjuvant chemotherapy response rates and higher overall and cancer specific mortality as well as bladder cancer recurrence after radical cystectomy. Appropriate preoperative counseling, together with tightened followup, may have a pivotal role in improving the smoking-related long-term survival outcomes in patients with bladder cancer.


Assuntos
Cistectomia , Fumar/efeitos adversos , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/cirurgia , Quimioterapia Adjuvante , Cistectomia/métodos , Humanos , Terapia Neoadjuvante , Taxa de Sobrevida , Resultado do Tratamento , Neoplasias da Bexiga Urinária/tratamento farmacológico
3.
Indian J Exp Biol ; 51(12): 1120-4, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24579378

RESUMO

A novel combination of plant growth regulators comprising indole-3-butyric acid (IBA), 6-benzylaminopurine (BA) and gibberellic acid (GA3) in Murashige and Skoog basal medium has been formulated for in vitro induction of both shoot and root in one culture using cotyledonary node explants of guar, (Cyamopsis tetragonoloba). Highest percentages of shoot (92%) and root (80%) induction were obtained in the medium containing (mg/L) 2 IBA, 3 BA and 1 GA3. Shoot regeneration from the cotyledonary node explants was observed after 10-15 days. Regeneration of roots from these shoots occurred after 20 to 25 days. The regenerated plantlets showed successful acclimatization on transfer to soil. This protocol is expected to be helpful in carrying out various in vitro manipulations in this economically and industrially important legume.


Assuntos
Cyamopsis/crescimento & desenvolvimento , Desenvolvimento Vegetal/efeitos dos fármacos , Reguladores de Crescimento de Plantas/farmacologia , Compostos de Benzil , Cyamopsis/efeitos dos fármacos , Giberelinas/farmacologia , Indóis/farmacologia , Cinetina/farmacologia , Reguladores de Crescimento de Plantas/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Purinas
4.
Acta Biomater ; 3(3): 341-50, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17234464

RESUMO

Novel microcidal silver films for burn dressings have been produced by magnetron sputtering. The nanostructure and dissolution characteristics of these films exhibiting antimicrobial behavior were studied as a function of the process conditions, namely, gas composition, gas pressure and input power, using transmission electron microscopy (TEM), high-resolution scanning electron microscopy, X-ray photoelectron spectroscopy (XPS) and resistivity. TEM revealed that bioactive films were nanocrystalline, with a grain size of the order of 15nm and the presence of twins. Surface morphology studies before and after dissolution suggested that bioactive films released silver at therapeutic levels in the form of nanoparticles or grains. Chemical species identification with XPS showed that the biologically active films were metallic in nature. The importance of oxygen in the sputtering environment, the resultant nanostructure and presence of twins are discussed to explain the unique antimicrobial properties of these silver films.


Assuntos
Anti-Infecciosos/química , Magnetismo , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Prata/química , Materiais Revestidos Biocompatíveis/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanotecnologia/métodos , Pseudomonas aeruginosa/efeitos dos fármacos , Solubilidade , Análise Espectral/métodos , Staphylococcus aureus/efeitos dos fármacos , Propriedades de Superfície , Volatilização , Água/química
5.
Indian J Med Res ; 123(4): 553-60, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16783047

RESUMO

BACKGROUND & OBJECTIVE: The viral encephalitides caused by animal or human viruses are characterized by sudden outbreaks of neurological disease in both tropical and temperate regions. An outbreak of acute encephalitis occurred in Siliguri (West Bengal) town of India between January 31 and February 23, 2001. This outbreak was investigated by a team of scientists from four major institutions, and the findings are presented here. METHODS: Detailed information about the outbreak was collected with the help of local health authorities. Limited entomological investigations were also done. Samples collected from cases and contacts were sent for analysis. RESULTS: A total of 66 probable cases and 45 deaths were reported. Epidemiological linkages between cases point towards person-to-person transmission and incubation period of around 10 days. There was neither any concurrent illness in animals nor was there any exposure of cases to animals. Centres for Disease Control and Prevention, Atlanta, USA concluded on the basis of tests carried out on serum specimen from four cases and two contacts that the causative pathogen appears to be Nipah/ Hendra or closely related virus. INTERPRETATION & CONCLUSION: This outbreak highlights the importance and urgency of establishing a strong surveillance system supported by a network of state-of-the-art laboratories equipped to handle and diagnose new pathogens and including patient isolation techniques, use of personal protective equipment, barrier nursing and safe disposal of potentially infected material in the prevention and control measures for Nipah/Hendra virus infection.


Assuntos
Vírus Hendra , Infecções por Henipavirus/epidemiologia , Vírus Nipah , Adolescente , Adulto , Idoso , Animais , Criança , Surtos de Doenças , Vetores de Doenças , Encefalite Viral/epidemiologia , Encefalite Viral/transmissão , Feminino , Infecções por Henipavirus/transmissão , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade
6.
Genome ; 49(5): 531-44, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16767178

RESUMO

The US Wheat Genome Project, funded by the National Science Foundation, developed the first large public Triticeae expressed sequence tag (EST) resource. Altogether, 116,272 ESTs were produced, comprising 100,674 5' ESTs and 15 598 3' ESTs. These ESTs were derived from 42 cDNA libraries, which were created from hexaploid bread wheat (Triticum aestivum L.) and its close relatives, including diploid wheat (T. monococcum L. and Aegilops speltoides L.), tetraploid wheat (T. turgidum L.), and rye (Secale cereale L.), using tissues collected from various stages of plant growth and development and under diverse regimes of abiotic and biotic stress treatments. ESTs were assembled into 18,876 contigs and 23,034 singletons, or 41,910 wheat unigenes. Over 90% of the contigs contained fewer than 10 EST members, implying that the ESTs represented a diverse selection of genes and that genes expressed at low and moderate to high levels were well sampled. Statistical methods were used to study the correlation of gene expression patterns, based on the ESTs clustered in the 1536 contigs that contained at least 10 5' EST members and thus representing the most abundant genes expressed in wheat. Analysis further identified genes in wheat that were significantly upregulated (p < 0.05) in tissues under various abiotic stresses when compared with control tissues. Though the function annotation cannot be assigned for many of these genes, it is likely that they play a role associated with the stress response. This study predicted the possible functionality for 4% of total wheat unigenes, which leaves the remaining 96% with their functional roles and expression patterns largely unknown. Nonetheless, the EST data generated in this project provide a diverse and rich source for gene discovery in wheat.


Assuntos
Etiquetas de Sequências Expressas , Perfilação da Expressão Gênica , Triticum/genética , Triticum/metabolismo , Análise por Conglomerados , Mapeamento de Sequências Contíguas , Coleta de Dados , Bases de Dados Genéticas , Biblioteca Gênica , Genes de Plantas , Filogenia , Poliploidia , Distribuição Tecidual , Triticum/crescimento & desenvolvimento
7.
J Commun Dis ; 37(3): 173-81, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17080700

RESUMO

Entomological surveys were undertaken at some of the international airports/seaports (Bangalore, Calicut, Chennai, Cochin, Thiruvanathapuram and Vishakapatnam) to find out the breeding prevalence of dengue vector mosquito in diverse breeding containers from 1998 to 2004. Three vector indices (House index, Container index and Breateu index) were used to assess the breeding potential at each airport/seaport. International Health Regulations urged national governments to keep all the international airports/seaports and peripheral areas up to 400 meters free from Aedes aegypti mosquitoes. However, surveys revealed high vector indices at all the airports and seaports. Health authorities of airports/seaports need to take cognizance of these facts and develop action plan for appropriate control measures with emphasis on vector surveillance.


Assuntos
Aedes/fisiologia , Cruzamento , Dengue/transmissão , Insetos Vetores/fisiologia , Animais , Monitoramento Ambiental , Humanos , Índia , Controle de Mosquitos , Densidade Demográfica , Viagem
8.
Genetics ; 168(2): 585-93, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15514037

RESUMO

This report describes the rationale, approaches, organization, and resource development leading to a large-scale deletion bin map of the hexaploid (2n = 6x = 42) wheat genome (Triticum aestivum L.). Accompanying reports in this issue detail results from chromosome bin-mapping of expressed sequence tags (ESTs) representing genes onto the seven homoeologous chromosome groups and a global analysis of the entire mapped wheat EST data set. Among the resources developed were the first extensive public wheat EST collection (113,220 ESTs). Described are protocols for sequencing, sequence processing, EST nomenclature, and the assembly of ESTs into contigs. These contigs plus singletons (unassembled ESTs) were used for selection of distinct sequence motif unigenes. Selected ESTs were rearrayed, validated by 5' and 3' sequencing, and amplified for probing a series of wheat aneuploid and deletion stocks. Images and data for all Southern hybridizations were deposited in databases and were used by the coordinators for each of the seven homoeologous chromosome groups to validate the mapping results. Results from this project have established the foundation for future developments in wheat genomics.


Assuntos
Mapeamento Cromossômico , Biologia Computacional , Mapeamento de Sequências Contíguas , Etiquetas de Sequências Expressas/química , Deleção de Genes , Triticum/genética , Southern Blotting , Sondas de DNA , Biblioteca Gênica
9.
Genetics ; 168(2): 595-608, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15514038

RESUMO

A total of 37 original cDNA libraries and 9 derivative libraries enriched for rare sequences were produced from Chinese Spring wheat (Triticum aestivum L.), five other hexaploid wheat genotypes (Cheyenne, Brevor, TAM W101, BH1146, Butte 86), tetraploid durum wheat (T. turgidum L.), diploid wheat (T. monococcum L.), and two other diploid members of the grass tribe Triticeae (Aegilops speltoides Tausch and Secale cereale L.). The emphasis in the choice of plant materials for library construction was reproductive development subjected to environmental factors that ultimately affect grain quality and yield, but roots and other tissues were also included. Partial cDNA expressed sequence tags (ESTs) were examined by various measures to assess the quality of these libraries. All ESTs were processed to remove cloning system sequences and contaminants and then assembled using CAP3. Following these processing steps, this assembly yielded 101,107 sequences derived from 89,043 clones, which defined 16,740 contigs and 33,213 singletons, a total of 49,953 "unigenes." Analysis of the distribution of these unigenes among the libraries led to the conclusion that the enrichment methods were effective in reducing the most abundant unigenes and to the observation that the most diverse libraries were from tissues exposed to environmental stresses including heat, drought, salinity, or low temperature.


Assuntos
Etiquetas de Sequências Expressas/química , Biblioteca Gênica , Triticum/genética , Vetores Genéticos , Análise de Sequência de DNA , Técnica de Subtração
10.
Genetics ; 168(2): 609-23, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15514039

RESUMO

A total of 944 expressed sequence tags (ESTs) generated 2212 EST loci mapped to homoeologous group 1 chromosomes in hexaploid wheat (Triticum aestivum L.). EST deletion maps and the consensus map of group 1 chromosomes were constructed to show EST distribution. EST loci were unevenly distributed among chromosomes 1A, 1B, and 1D with 660, 826, and 726, respectively. The number of EST loci was greater on the long arms than on the short arms for all three chromosomes. The distribution of ESTs along chromosome arms was nonrandom with EST clusters occurring in the distal regions of short arms and middle regions of long arms. Duplications of group 1 ESTs in other homoeologous groups occurred at a rate of 35.5%. Seventy-five percent of wheat chromosome 1 ESTs had significant matches with rice sequences (E < or = e(-10)), where large regions of conservation occurred between wheat consensus chromosome 1 and rice chromosome 5 and between the proximal portion of the long arm of wheat consensus chromosome 1 and rice chromosome 10. Only 9.5% of group 1 ESTs showed significant matches to Arabidopsis genome sequences. The results presented are useful for gene mapping and evolutionary and comparative genomics of grasses.


Assuntos
Arabidopsis/genética , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Etiquetas de Sequências Expressas , Oryza/genética , Ploidias , Triticum/genética , Genes de Plantas , Genoma de Planta , Alinhamento de Sequência
11.
Genetics ; 168(2): 639-50, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15514041

RESUMO

The focus of this study was to analyze the content, distribution, and comparative genome relationships of 996 chromosome bin-mapped expressed sequence tags (ESTs) accounting for 2266 restriction fragments (loci) on the homoeologous group 3 chromosomes of hexaploid wheat (Triticum aestivum L.). Of these loci, 634, 884, and 748 were mapped on chromosomes 3A, 3B, and 3D, respectively. The individual chromosome bin maps revealed bins with a high density of mapped ESTs in the distal region and bins of low density in the proximal region of the chromosome arms, with the exception of 3DS and 3DL. These distributions were more localized on the higher-resolution group 3 consensus map with intermediate regions of high-mapped-EST density on both chromosome arms. Gene ontology (GO) classification of mapped ESTs was not significantly different for homoeologous group 3 chromosomes compared to the other groups. A combined analysis of the individual bin maps using 537 of the mapped ESTs revealed rearrangements between the group 3 chromosomes. Approximately 232 (44%) of the consensus mapped ESTs matched sequences on rice chromosome 1 and revealed large- and small-scale differences in gene order. Of the group 3 mapped EST unigenes approximately 21 and 32% matched the Arabidopsis coding regions and proteins, respectively, but no chromosome-level gene order conservation was detected.


Assuntos
Mapeamento Cromossômico , Cromossomos de Plantas/genética , Genes de Plantas , Oryza/genética , Triticum/genética , Genoma de Planta , Alinhamento de Sequência
12.
Genetics ; 168(2): 625-37, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15514040

RESUMO

The complex hexaploid wheat genome offers many challenges for genomics research. Expressed sequence tags facilitate the analysis of gene-coding regions and provide a rich source of molecular markers for mapping and comparison with model organisms. The objectives of this study were to construct a high-density EST chromosome bin map of wheat homoeologous group 2 chromosomes to determine the distribution of ESTs, construct a consensus map of group 2 ESTs, investigate synteny, examine patterns of duplication, and assess the colinearity with rice of ESTs assigned to the group 2 consensus bin map. A total of 2600 loci generated from 1110 ESTs were mapped to group 2 chromosomes by Southern hybridization onto wheat aneuploid chromosome and deletion stocks. A consensus map was constructed of 552 ESTs mapping to more than one group 2 chromosome. Regions of high gene density in distal bins and low gene density in proximal bins were found. Two interstitial gene-rich islands flanked by relatively gene-poor regions on both the short and long arms and having good synteny with rice were discovered. The map locations of two ESTs indicated the possible presence of a small pericentric inversion on chromosome 2B. Wheat chromosome group 2 was shown to share syntenous blocks with rice chromosomes 4 and 7.


Assuntos
Mapeamento Cromossômico , Cromossomos de Plantas/genética , Genes de Plantas , Oryza/genética , Triticum/genética , Genoma de Planta , Ploidias , Alinhamento de Sequência
13.
Genetics ; 168(2): 651-63, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15514042

RESUMO

A total of 1918 loci, detected by the hybridization of 938 expressed sequence tag unigenes (ESTs) from 26 Triticeae cDNA libraries, were mapped to wheat (Triticum aestivum L.) homoeologous group 4 chromosomes using a set of deletion, ditelosomic, and nulli-tetrasomic lines. The 1918 EST loci were not distributed uniformly among the three group 4 chromosomes; 41, 28, and 31% mapped to chromosomes 4A, 4B, and 4D, respectively. This pattern is in contrast to the cumulative results of EST mapping in all homoeologous groups, as reported elsewhere, that found the highest proportion of loci mapped to the B genome. Sixty-five percent of these 1918 loci mapped to the long arms of homoeologous group 4 chromosomes, while 35% mapped to the short arms. The distal regions of chromosome arms showed higher numbers of loci than the proximal regions, with the exception of 4DL. This study confirmed the complex structure of chromosome 4A that contains two reciprocal translocations and two inversions, previously identified. An additional inversion in the centromeric region of 4A was revealed. A consensus map for homoeologous group 4 was developed from 119 ESTs unique to group 4. Forty-nine percent of these ESTs were found to be homoeologous to sequences on rice chromosome 3, 12% had matches with sequences on other rice chromosomes, and 39% had no matches with rice sequences at all. Limited homology (only 26 of the 119 consensus ESTs) was found between wheat ESTs on homoeologous group 4 and the Arabidopsis genome. Forty-two percent of the homoeologous group 4 ESTs could be classified into functional categories on the basis of blastX searches against all protein databases.


Assuntos
Mapeamento Cromossômico , Cromossomos de Plantas/genética , Etiquetas de Sequências Expressas , Genes de Plantas , Triticum/genética , Deleção de Genes , Duplicação Gênica , Biblioteca Gênica , Genoma de Planta
14.
Genetics ; 168(2): 677-86, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15514044

RESUMO

To localize wheat (Triticum aestivum L.) ESTs on chromosomes, 882 homoeologous group 6-specific ESTs were identified by physically mapping 7965 singletons from 37 cDNA libraries on 146 chromosome, arm, and sub-arm aneuploid and deletion stocks. The 882 ESTs were physically mapped to 25 regions (bins) flanked by 23 deletion breakpoints. Of the 5154 restriction fragments detected by 882 ESTs, 2043 (loci) were localized to group 6 chromosomes and 806 were mapped on other chromosome groups. The number of loci mapped was greatest on chromosome 6B and least on 6D. The 264 ESTs that detected orthologous loci on all three homoeologs using one restriction enzyme were used to construct a consensus physical map. The physical distribution of ESTs was uneven on chromosomes with a tendency toward higher densities in the distal halves of chromosome arms. About 43% of the wheat group 6 ESTs identified rice homologs upon comparisons of genome sequences. Fifty-eight percent of these ESTs were present on rice chromosome 2 and the remaining were on other rice chromosomes. Even within the group 6 bins, rice chromosomal blocks identified by 1-6 wheat ESTs were homologous to up to 11 rice chromosomes. These rice-block contigs were used to resolve the order of wheat ESTs within each bin.


Assuntos
Mapeamento Cromossômico , Cromossomos de Plantas/genética , Deleção de Genes , Genes de Plantas , Triticum/genética , Etiquetas de Sequências Expressas , Biblioteca Gênica , Genoma de Planta , Alinhamento de Sequência
15.
Genetics ; 168(2): 665-76, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15514043

RESUMO

We constructed high-density deletion bin maps of wheat chromosomes 5A, 5B, and 5D, including 2338 loci mapped with 1052 EST probes and 217 previously mapped loci (total 2555 loci). This information was combined to construct a consensus chromosome bin map of group 5 including 24 bins. A relatively higher number of loci were mapped on chromosome 5B (38%) compared to 5A (34%) and 5D (28%). Differences in the levels of polymorphism among the three chromosomes were partially responsible for these differences. A higher number of duplicated loci was found on chromosome 5B (42%). Three times more loci were mapped on the long arms than on the short arms, and a significantly higher number of probes, loci, and duplicated loci were mapped on the distal halves than on the proximal halves of the chromosome arms. Good overall colinearity was observed among the three homoeologous group 5 chromosomes, except for the previously known 5AL/4AL translocation and a putative small pericentric inversion in chromosome 5A. Statistically significant colinearity was observed between low-copy-number ESTs from wheat homoeologous group 5 and rice chromosomes 12 (88 ESTs), 9 (72 ESTs), and 3 (84 ESTs).


Assuntos
Mapeamento Cromossômico , Cromossomos de Plantas/genética , Genes de Plantas , Oryza/genética , Triticum/genética , Etiquetas de Sequências Expressas , Genoma de Planta , Alinhamento de Sequência
16.
Genetics ; 168(2): 687-99, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15514045

RESUMO

The objectives of this study were to develop a high-density chromosome bin map of homoeologous group 7 in hexaploid wheat (Triticum aestivum L.), to identify gene distribution in these chromosomes, and to perform comparative studies of wheat with rice and barley. We mapped 2148 loci from 919 EST clones onto group 7 chromosomes of wheat. In the majority of cases the numbers of loci were significantly lower in the centromeric regions and tended to increase in the distal regions. The level of duplicated loci in this group was 24% with most of these loci being localized toward the distal regions. One hundred nineteen EST probes that hybridized to three fragments and mapped to the three group 7 chromosomes were designated landmark probes and were used to construct a consensus homoeologous group 7 map. An additional 49 probes that mapped to 7AS, 7DS, and the ancestral translocated segment involving 7BS also were designated landmarks. Landmark probe orders and comparative maps of wheat, rice, and barley were produced on the basis of corresponding rice BAC/PAC and genetic markers that mapped on chromosomes 6 and 8 of rice. Identification of landmark ESTs and development of consensus maps may provide a framework of conserved coding regions predating the evolution of wheat genomes.


Assuntos
Mapeamento Cromossômico , Cromossomos de Plantas/genética , Etiquetas de Sequências Expressas , Genes de Plantas , Triticum/genética , Deleção de Genes , Duplicação Gênica , Marcadores Genéticos , Genoma de Planta , Hordeum/genética , Oryza/genética , Alinhamento de Sequência
17.
Genetics ; 168(2): 701-12, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15514046

RESUMO

Because of the huge size of the common wheat (Triticum aestivum L., 2n = 6x = 42, AABBDD) genome of 17,300 Mb, sequencing and mapping of the expressed portion is a logical first step for gene discovery. Here we report mapping of 7104 expressed sequence tag (EST) unigenes by Southern hybridization into a chromosome bin map using a set of wheat aneuploids and deletion stocks. Each EST detected a mean of 4.8 restriction fragments and 2.8 loci. More loci were mapped in the B genome (5774) than in the A (5173) or D (5146) genomes. The EST density was significantly higher for the D genome than for the A or B. In general, EST density increased relative to the physical distance from the centromere. The majority of EST-dense regions are in the distal parts of chromosomes. Most of the agronomically important genes are located in EST-dense regions. The chromosome bin map of ESTs is a unique resource for SNP analysis, comparative mapping, structural and functional analysis, and polyploid evolution, as well as providing a framework for constructing a sequence-ready, BAC-contig map of the wheat genome.


Assuntos
Mapeamento Cromossômico , Cromossomos de Plantas/genética , Etiquetas de Sequências Expressas , Genes de Plantas , Genoma de Planta , Triticum/genética , Marcadores Genéticos , Ploidias , Locos de Características Quantitativas , Alinhamento de Sequência
18.
Hereditas ; 141(1): 55-60, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15383072

RESUMO

Flow sorting maize chromosome 1 and construction of the first chromosome 1 DNA Lambda library are described. Maize metaphase chromosome suspensions were prepared from synchronized seedling root tip cells of the maize hybrid line Seneca 60 and stained with propidium iodide for flow karyotyping and sorting. The observed flow karyotype was very similar to the predicted flow karyotype constructed based on published values for the relative chromosome sizes of Seneca 60. The estimated size of chromosomes from the peak for the chromosome 1 matched the expected size of maize chromosome 1. The peak for the chromosome 1 was well resolved from other peaks on the flow karyotype. An average of 7 x 10(3) chromosomes of chromosome 1 could be produced from 10 root tips. About 0.6 million chromosomes of maize chromosome 1 were sorted and pooled based on the cytogram of fluorescent pulse area Vs fluorescent pulse width and stored at -20 degrees C in the freezer. DNA isolated from sorted chromosomes was good quality of more than 100 kb in size. Chromosome 1 DNA was partially digested with BamHI, dephosphorylated and ligated with arms of BamHI digested Lambda Dash vector. A total of 1.2 x 10(5) independent recombinants with the average insert size 12.6 kb was obtained. This library covered approximately 90% of maize chromosome 1. Hybridization of cloned fragments with labeled maize genomic DNA showed that the high, middle, or low copy number DNA sequences presented in the different phage clones. PCR (polymerase chain reaction) using chromosome-specific primers confirmed the specificity of this library. The individual chromosome library is useful in plant genome mapping and gene isolation.


Assuntos
Cromossomos de Plantas/genética , Zea mays/genética , Clonagem Molecular , DNA de Plantas/genética , DNA de Plantas/isolamento & purificação , Citometria de Fluxo , Biblioteca Gênica , Cariotipagem
19.
Theor Appl Genet ; 109(7): 1494-503, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15290051

RESUMO

Previous studies with chromosome substitution and recombinant inbred chromosome lines identified that chromosome 3A of wheat cv. Wichita contains alleles that influence grain yield, yield components and agronomic performance traits relative to alleles on chromosome 3A of Cheyenne, a cultivar believed to be the founder parent of many Nebraska developed cultivars. This study was carried out to examine the genetic similarity among wheat cultivars based on the variation in chromosome 3A. Forty-eight cultivars, two promising lines and four substitution lines (in duplicate) were included in the study. Thirty-six chromosome 3A-specific and 12 group-3 barley simple sequence repeat (SSR) primer pairs were used. A total of 106 polymorphic bands were scored. Transferability of barley microsatellite markers to wheat was 73%. The coefficient of genetic distance (D) among the genotypes ranged from 0.40 to 0.91 and averaged D=0.66. Cluster analysis by the unweighted pair-group method with arithmetic averages showed one large and one small cluster with eight minor clusters in the large cluster. Several known pedigree relationships largely corresponded with the results of SSR clusters and principal coordinate analysis. Cluster analysis was also carried out by using 22 alleles that separate Wichita 3A from Cheyenne 3A, and three clusters were identified (a small cluster related to Cheyenne of mainly western Nebraska wheat cultivars; a larger, intermediate cluster with many modern Nebraska wheat cultivars; a large cluster related to Wichita with many modern high-yielding or Kansas wheat cultivars). Using three SSR markers that identify known agronomically important quantitative trait loci (QTL) regions, we again separated the cultivars into three main clusters that were related to Cheyenne or Wichita, or had a different 3A lineage. These results suggest that SSR markers linked to agronomically important QTLs are a valuable asset for estimating both genetic similarity for chromosome 3A and how the chromosome has been used in cultivar improvement.


Assuntos
Cromossomos de Plantas/genética , Repetições de Microssatélites/genética , Triticum/genética , Pão , Mapeamento Cromossômico , DNA de Plantas/genética , Marcadores Genéticos , Filogenia , Reação em Cadeia da Polimerase/métodos , Estações do Ano , Especificidade da Espécie , Triticum/classificação , Estados Unidos
20.
Leuk Lymphoma ; 44(2): 309-11, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12688350

RESUMO

A kindred with familial leukemia is described in which three members are affected by leukemia in three consecutive generations. One of these members had Philadelphia positive chronic myeloid leukemia (CML) and other two had precursor B acute lymphoblasticleukemia (ALL)--Philadelphia negative. All three of them shared a common haplotype A2, B55, Cw3. In addition, another member sharing same haplotype developed metastatic breast cancer. Phenomenon of anticipation is demonstrated in the affected family members. Possible causes of genetic susceptibility to leukemia especially the association of Cw3 with familial leukemia are discussed.


Assuntos
Predisposição Genética para Doença , Antígenos HLA-C/análise , Leucemia/etiologia , Adolescente , Adulto , Neoplasias da Mama/etiologia , Neoplasias da Mama/patologia , Saúde da Família , Haplótipos , Humanos , Leucemia/imunologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/etiologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Masculino , Pessoa de Meia-Idade , Linhagem , Leucemia-Linfoma Linfoblástico de Células Precursoras B/etiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia
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