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1.
Indian J Hematol Blood Transfus ; 39(1): 90-101, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36699436

RESUMO

Anemia remains a significant public health challenge, disproportionately impacting lower-income patients residing in areas of lesser healthcare resources. We sought to evaluate the accuracy of physical exam techniques to diagnose anemia among patients 5 years of age or older. A systematic review of 5 databases (MEDLINE via OVID, EMBASE, Scopus, Global Health and Global Health Archives, and WHO Global Index Medicus) was conducted. Studies that (1) compared non-invasive physical exam techniques with anemia diagnoses using standard laboratory measurements and (2) solely assessed or separately reported the diagnostic accuracy of physical exam techniques for patients 5 years or older were considered for inclusion. The diagnostic accuracies of individual and combinatorial physical exam techniques todiagnose anemia were documented. This systematic review was registered with PROSPERO. The systemic literature search yielded 6,457 unique studies after removal of duplicates. Fourteen studies were ultimately selected for inclusion. Eight studies solely assessed pregnant females, 4 solely assessed hospitalized patients, and 2 evaluated the general population. The diagnostic accuracy ranged widely for pallor assessments of conjunctivae (sensitivity: 19-97%, specificity: 65-100%), nailbed (sensitivity: 41-65%, specificity: 58-93%), and palms (sensitivity: 33-91%, specificity: 54-93%). Examining 9 or more sites leads to higher sensitivity (73.8-82.9%) and specificity (76.0-90.9%). No individual examination technique is superior to others for diagnosing anemia. Combinatorial approachs are associated with more acceptable accuracy measures, but improvements need to be balanced with time available for examination. Supplementary Information: The online version contains supplementary material available at 10.1007/s12288-022-01543-z.

2.
Nat Food ; 2(10): 819-827, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37117978

RESUMO

The effective utilization of natural variation has become essential in addressing the challenges that climate change and population growth pose to global food security. Currently adopted protracted approaches to introgress exotic alleles into elite cultivars need substantial transformation. Here, through a strategic three-way crossing scheme among diverse exotics and the best historical elites (exotic/elite1//elite2), 2,867 pre-breeding lines were developed, genotyped and screened for multiple agronomic traits in four mega-environments. A meta-genome-wide association study, selective sweeps and haplotype-block-based analyses unveiled selection footprints in the genomes of pre-breeding lines as well as exotic-specific associations with agronomic traits. A simulation with a neutrality assumption demonstrated that many pre-breeding lines had significant exotic contributions despite substantial selection bias towards elite genomes. National breeding programmes worldwide have adopted 95 lines for germplasm enhancement, and 7 additional lines are being advanced in varietal release trials. This study presents a great leap forwards in the mobilization of GenBank variation to the breeding pipelines.

3.
Sci Rep ; 10(1): 5999, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32265455

RESUMO

This study was initiated to identify genomic regions conferring resistance to Karnal Bunt (KB) disease in wheat through a genome-wide association study (GWAS) on a set of 179 pre-breeding lines (PBLs). A GWAS of 6,382 high-quality DArTseq SNPs revealed 15 significant SNPs (P-value <10-3) on chromosomes 2D, 3B, 4D and 7B that were associated with KB resistance in individual years. In particular, two SNPs (chromosome 4D) had the maximum R2 values: SNP 1114200 | F | 0-63:T > C at 1.571 cM and R2 of 12.49% and SNP 1103052 | F | 0-61:C > A at 1.574 cM and R2 of 9.02%. These two SNPs displayed strong linkage disequilibrium (LD). An in silico analysis of SNPs on chromosome 4D identified two candidate gene hits, TraesCS4D02G352200 (TaNox8; an NADPH oxidase) and TraesCS4D02G350300 (a rhomboid-like protein belonging to family S54), with SNPs 1103052 | F | 0-61:C > A and 1101835 | F | 0-5:C > A, respectively, both of which function in biotic stress tolerance. The epistatic interaction analysis revealed significant interactions among 4D and 7B loci. A pedigree analysis of confirmed resistant PBLs revealed that Aegilops species is one of the parents and contributed the D genome in these resistant PBLs. These identified lines can be crossed with any elite cultivar across the globe to incorporate novel KB resistance identified on 4B.


Assuntos
Doenças das Plantas/genética , Triticum/genética , Cromossomos de Plantas , Resistência à Doença , Epistasia Genética , Loci Gênicos , Estudo de Associação Genômica Ampla , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único
4.
Scand J Immunol ; 67(6): 544-52, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18397199

RESUMO

Infectious diseases are the greatest cause of global morbidity and mortality. About half of this burden is caused by pathogenic bacteria. One of the most effective ways to prevent infectious diseases is to use vaccines. Limitations in the traditional approaches may be one of the reasons why vaccines are yet not available against some infectious bacterial agents. Recent advancements in high-throughput 'omics' technologies and the availability of complete genome sequences of microbial pathogens and multiple isolates of the same species have dramatically changed the time frame and scope for identifying novel vaccine candidates. At present, 582 microbial genomes have been sequenced and sequencing of 1733 is in progress. There are more than 50 bacterial species for which the genome sequence is available for three or more isolates. Development of tools for in silico analysis has led to the identification of novel virulence genes, metabolic pathways and cell surface proteins that represent potential new targets for anti-microbial drug and vaccine strategies. In this review, we provide an overview of the 'omics'-based techniques that can be used to advance and accelerate the discovery of vaccine candidates against extracellular bacterial pathogens. By citing specific examples, we discuss how high-throughput molecular profiling techniques, such as genomics, transcriptomics and proteomics have contributed to the discovery of novel vaccine candidates. We end by contemplating on the emerging technologies that are likely to have a high impact on the field of vaccinology in the near future.


Assuntos
Infecções Bacterianas/prevenção & controle , Vacinas Bacterianas , Genoma Bacteriano , Genômica , Animais , Antígenos de Bactérias/genética , Bactérias/genética , Bactérias/patogenicidade , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Humanos , Proteômica , Análise de Sequência , Virulência/genética
5.
Sci Rep ; 6: 27312, 2016 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-27311707

RESUMO

Genomic and pedigree predictions for grain yield and agronomic traits were carried out using high density molecular data on a set of 803 spring wheat lines that were evaluated in 5 sites characterized by several environmental co-variables. Seven statistical models were tested using two random cross-validations schemes. Two other prediction problems were studied, namely predicting the lines' performance at one site with another (pairwise-site) and at untested sites (leave-one-site-out). Grain yield ranged from 3.7 to 9.0 t ha(-1) across sites. The best predictability was observed when genotypic and pedigree data were included in the models and their interaction with sites and the environmental co-variables. The leave-one-site-out increased average prediction accuracy over pairwise-site for all the traits, specifically from 0.27 to 0.36 for grain yield. Days to anthesis, maturity, and plant height predictions had high heritability and gave the highest accuracy for prediction models. Genomic and pedigree models coupled with environmental co-variables gave high prediction accuracy due to high genetic correlation between sites. This study provides an example of model prediction considering climate data along-with genomic and pedigree information. Such comprehensive models can be used to achieve rapid enhancement of wheat yield enhancement in current and future climate change scenario.


Assuntos
Agricultura , Grão Comestível/genética , Triticum/genética , Pão , Meio Ambiente , Variação Genética/genética , Genoma de Planta/genética , Genótipo , Modelos Estatísticos , Estações do Ano , Tempo (Meteorologia)
6.
Gene ; 181(1-2): 113-6, 1996 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-8973317

RESUMO

Shotgun sequencing of cDNA clones is now an established approach to gain insight into the expressed nucleotide (nt) sequences in a given cell. We analysed 100 randomly picked cDNA clones of the protozoan parasite, Entamoeba histolytica, by nt sequencing, with a view to obtain novel gene sequences not detected so far by biochemical and genetic analyses. About 56% of the analysed clones showed significant homology with other genes in the database, including a number of genes whose presence may not be suspected in E. histolytica owing to its unusual subcellular organization. The results suggest that this approach can provide important clues to understand unique biochemical mechanisms in this parasite.


Assuntos
Entamoeba histolytica/genética , Animais , DNA Complementar , DNA de Protozoário , Genes de Protozoários , Dados de Sequência Molecular , Análise de Sequência de DNA
7.
Mol Biochem Parasitol ; 67(2): 205-14, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7870125

RESUMO

We have sequenced the extrachromsomal ribosomal DNA (rDNA) circle of the human protozoan parasite Entamoeba histolytica HM-1:IMSS and present here the complete sequence organisation of the 24.5-kb molecule. Each circle contains two 5.9-kb rDNA transcription units organised as inverted repeats. The regions downstream (3543 bp) and upstream (9216 bp) of the rDNAs contain various families of short tandem repeats. Some of the upstream repeats share extensive sequence homology with the downstream repeats. In addition to the rDNAs themselves, the rDNA circle appears to code for only one other transcript which is 0.7 kb in size as seen in Northern blots. From DNA sequence analysis, no open reading frame could be assigned to the transcript. Extrachromosomal rDNA circles also exist in other E. histolytica strains. Restriction enzyme maps of rDNA circles were constructed from E. histolytica strains 200:NIH, HK-9 and Rahman; and Entamoeba moshkovskii strain Laredo. Striking differences were observed in the organisation of some of them, e.g. the HK-9, Rahman and Laredo circles contained only one rDNA unit and lacked the 0.7-kb transcript sequence. The short repeat sequences upstream and downstream of rDNAs were present in HK-9 and Rahman but absent in Laredo. Circles with one rDNA unit may be derived from those with two units by homologous recombination at direct repeat sequences located upstream and downstream of the two rDNAs.


Assuntos
Núcleo Celular/genética , DNA Ribossômico/genética , Entamoeba histolytica/genética , Animais , Sequência de Bases , Northern Blotting , Herança Extracromossômica/genética , Genes de Protozoários/genética , Dados de Sequência Molecular , Plasmídeos
8.
Biotechniques ; 25(6): 997-1000, 1002, 1004 passim, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9863053

RESUMO

The gene encoding the green fluorescent protein (gfp) under the control of the highly expressed Autographa californica nucleopolyhedrovirus (AcMNPV)-polyhedrin promoter has been introduced into the polyhedrin (polh) locus of Bombyx mori nucleopolyhedrovirus (BmNPV) by homologous recombination. The insect host larvae and the cultured cells infected with this recombinant virus (vBmGFP) showed high levels of expression of gfp. The larval tissues permissive to virus multiplication could be readily visualized using the tagged recombinant virus, thus providing a direct approach to study the progress of virus infection or its control in the animal host. The highly expressed recombinant protein, GFP, could be easily solubilized from fat bodies. Thus, the caterpillar-based expression could serve as an economic alternative method for the large-scale production of recombinant proteins, even when they are nonsecretory in nature. Further, if the recombinant vBmGFP is used as a parent in generating other recombinants, conversion of the fluorescent plaques to colorless plaques serves as an easy means for screening recombinants. Such a method is especially helpful for BmNPV-recombinant selections in the absence of the other simplified techniques as are available for the prototype baculovirus AcMNPV system.


Assuntos
Bombyx/virologia , Indicadores e Reagentes/metabolismo , Proteínas Luminescentes/genética , Nucleopoliedrovírus/genética , Proteínas Recombinantes de Fusão/genética , Animais , Baculoviridae/genética , Células Cultivadas , Regulação Viral da Expressão Gênica , Genes de Insetos , Genes Reporter , Testes Genéticos/métodos , Proteínas de Fluorescência Verde , Larva/genética , Plasmídeos , Regiões Promotoras Genéticas
9.
Vet Immunol Immunopathol ; 72(1-2): 7-15, 1999 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-10614487

RESUMO

Combinatorial diversity is limited in rabbits because only a few V(H) genes rearrange. Most diversification of the primary repertoire is generated by somatic hypermutation and gene conversion-like changes of rearranged V(H) in B cells that migrate to appendix and other gut associated lymphoid tissues (GALT) of young rabbits. The changes are referred to as gene conversion-like because the non-reciprocal nature of the alterations introduced has not yet been demonstrated. There are many similarities between rabbits and chickens in how their B cells develop and diversify their repertoires. However, although the majority of rabbit B cells may have rearranged and diversified their V genes early in life, some B cells in adult rabbits have rearranged VH sequences that are identical or nearly identical to germline sequences. We found these cells in splenic germinal centers (GC) on days 7 and 10 after immunization of normal adult rabbits with DNP-BGG. By day 15, all rearranged V(H) sequences were diversified. We find an overall pattern of splenic precursor cells whose germline or near germline sequences change both by gene conversion and point mutations during early divisions and mainly by point mutations during later divisions. These events, in parallel with diversification of light chain sequences, may produce the diverse combining sites that serve as substrates for further affinity maturation by selection either within GC or later among emigrant cells in sites such as bone marrow. Some of the sequences altered by gene conversion in splenic germinal centers may also produce new members of the B-cell repertoire in adult rabbits comparable to those produced in GALT of neonatal rabbits.


Assuntos
Diversidade de Anticorpos/genética , Linfócitos B/imunologia , Conversão Gênica/genética , Genes de Imunoglobulinas/genética , Centro Germinativo/imunologia , Coelhos/genética , Animais , Diversidade de Anticorpos/imunologia , Apêndice/imunologia , Conversão Gênica/imunologia , Genes de Imunoglobulinas/imunologia , Variação Genética/genética , Coelhos/imunologia , Baço/imunologia
10.
ISRN Dent ; 2011: 102329, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21991454

RESUMO

Purpose. To analyze the stress distribution in an endodontically treated maxillary central incisor restored with various post-core systems and assess the benefit of ferrule using finite element analysis. Material and Methods. Twelve models with metal ceramic crown were created based on the combination of three types of post-core systems (titanium post-composite resin core, nickel-chromium post-core, and fiber reinforced composite resin post-composite resin core), two varieties of posts (tapered, parallel), and with or without ferrule. 100 N load was applied in three directions and the von Mises stress was compared. Results. Ferrule made no difference in stress distribution for the titanium and nickel-chromium posts, though it showed some stress reduction in fiber-reinforced composite resin posts. Nickel-chromium cast post-core transmitted the least amount of stresses to the dentin despite producing the maximum stress. Conclusion. Incorporation of ferrule offered some degree of stress reduction in nonmetal post, and it increased the stresses within cervical dentin.

19.
Anal Biochem ; 218(1): 87-91, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8053572

RESUMO

Water-soluble carbodiimides are widely used for carboxyl-amine conjugation. However, extremely variable and low yields, obtained under a variety of conditions, have been a serious problem in the coupling. A simple method, optimizing various parameters of the coupling reaction, in which N-hydroxysuccinimide is included to assist the 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride-catalyzed amidation reaction is described. A product yield of up to 90% is routinely achieved.


Assuntos
Amidas/química , Etildimetilaminopropil Carbodi-Imida/química , Glândulas Mamárias Animais/enzimologia , Água/química , alfa-Glucosidases/isolamento & purificação , Animais , Catálise , Feminino , Estrutura Molecular , Ratos , Solubilidade
20.
J Immunol ; 160(3): 1246-55, 1998 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9570541

RESUMO

We investigated the molecular basis for the appearance of V(H)a2 allotype-bearing B cells in mutant Alicia rabbits. The mutation arose in an a2 rabbit; mutants exhibit altered expression of V(H) genes because of a small deletion encompassing V(H)1a2, the 3'-most gene in the V(H) locus. The V(H)1 gene is the major source of V(H)a allotype because this gene is preferentially rearranged in normal rabbits. In young homozygous ali/ali animals, the levels of a2 molecules found in the serum increase with age. In adult ali/ali rabbits, 20 to 50% of serum Igs and B cells bear a2 allotypic determinants. Previous studies suggested that positive selection results in expansion of a2 allotype-bearing B cells in the appendix of young mutant ali/ali rabbits. We separated appendix cells from a 6-wk-old Alicia rabbit by FACS based on the expression of surface IgM and a2 allotype. The VDJ portion of the expressed Ig mRNA was amplified from the IgM+ a2+ and IgM+ a2- populations by reverse transcriptase-PCR. The cDNAs from both populations were cloned and sequenced. Analysis of these sequences suggested that, in a2+ B cells, the first D proximal functional gene in Alicia rabbits, V(H)4a2, rearranged and was altered further by a gene conversion-like mechanism. Upstream V(H) genes were identified as potential gene sequence donors; V(H)9 was found to be the most frequently used gene donor. Among the a2- B cells, y33 was the most frequently rearranged gene.


Assuntos
Apêndice/imunologia , Linfócitos B/imunologia , Conversão Gênica/imunologia , Rearranjo Gênico de Cadeia Pesada de Linfócito B/imunologia , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Mutação , Sequência de Aminoácidos , Animais , Diversidade de Anticorpos/genética , Apêndice/citologia , Linfócitos B/metabolismo , Sequência de Bases , Citometria de Fluxo , Genes de Imunoglobulinas , Alótipos de Imunoglobulina , Imunoglobulina M/genética , Dados de Sequência Molecular , Família Multigênica , Coelhos , Análise de Sequência de DNA
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