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1.
J Clin Pharm Ther ; 39(5): 527-34, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24943987

RESUMEN

WHAT IS KNOWN AND OBJECTIVES: About half of all patients taking antihypertensives discontinue treatment by 12 months. There is potential for substantial health gains at both individual and population levels through improved treatment adherence. The objective was to evaluate a community pharmacist intervention to improve adherence with antihypertensive medicines with a view to improving blood pressure (BP) control. DESIGN: prospective, non-blinded, cluster-randomized, controlled trial. PARTICIPANTS: adults with primary hypertension who obtained antihypertensives in the previous 6 months. Patients with poor refill adherence were preferentially identified with the help of a purpose-built software application. INTERVENTION: package comprising BP monitor; training on BP self-monitoring; motivational interviewing; medication use review; prescription refill reminders. FOLLOW-UP: six months. PRIMARY OUTCOME: change in proportion self-reporting medication adherence. Secondary outcome: BP changes. RESULTS: Participants (n = 395; intervention - 207; control - 188) had a mean age of 66.7 years; 51.1% were males. The proportion of adherent participants increased in both groups but was not significantly different between groups [57·2% to 63·6% (control) vs. 60·0% to 73·5% (intervention), P = 0·23]. The mean reduction in systolic BP was significantly greater in the intervention group (10·0 mmHg vs. 4·6 mmHg; P = 0·05). The proportion of patients who were non-adherent at baseline and adherent at 6 months was 22·6% (95%CI 5·1-40·0%) higher in the intervention group (61·8% vs. 39·2%, P = 0·007). Among participants with baseline BP above target, reduction of systolic BP was significantly greater in the intervention group [by 7·2 mmHg (95%CI 1·6-12·8 mmHg); (P = 0·01)]. Among participants non-adherent at baseline and above target BP, the proportion reporting adherence at 6 months was significantly greater in the intervention group [56·8% vs. 35·9%, P = 0·039). WHAT IS NEW AND CONCLUSION: This community pharmacist intervention resulted in improved adherence to antihypertensive medication and reduced systolic BP.


Asunto(s)
Antihipertensivos/administración & dosificación , Servicios Comunitarios de Farmacia , Hipertensión/tratamiento farmacológico , Cumplimiento de la Medicación , Anciano , Monitoreo Ambulatorio de la Presión Arterial , Femenino , Humanos , Masculino , Farmacéuticos , Resultado del Tratamiento , Victoria
2.
Curr Opin Plant Biol ; 4(6): 561-7, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11641074

RESUMEN

Recent studies have expanded our view of the interactions between small molecule signals that regulate the hypersensitive response and other forms of cell suicide in plants. The mitochondrion has received increasing support as a mediator of at least some forms of programmed cell death in plants. In addition, new information provides a glimpse of how plant hormone signaling may be integrated with extensive autolysis, sensitivity to reactive oxygen intermediates and cell death.


Asunto(s)
Apoptosis/fisiología , Magnoliopsida/fisiología , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Adaptación Fisiológica , Magnoliopsida/microbiología , Transducción de Señal
3.
Plant J ; 22(6): 523-9, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10886772

RESUMEN

To better understand the genetic requirements for R gene-dependent defense activation in Arabidopsis, we tested the effect of several defense response mutants on resistance specified by eight RPP genes (for resistance to Peronospora parasitica) expressed in the Col-0 background. In most cases, resistance was not suppressed by a mutation in the SAR regulatory gene NPR1 or by expression of the NahG transgene. Thus, salicylic acid accumulation and NPR1 function are not necessary for resistance mediated by these RPP genes. In addition, resistance conferred by two of these genes, RPP7 and RPP8, was not significantly suppressed by mutations in either EDS1 or NDR1. RPP7 resistance was also not compromised by mutations in EIN2, JAR1 or COI1 which affect ethylene or jasmonic acid signaling. Double mutants were therefore tested. RPP7 and RPP8 were weakly suppressed in an eds1-2/ndr1-1 background, suggesting that these RPP genes operate additively through EDS1, NDR1 and as-yet-undefined signaling components. RPP7 was not compromised in coi1/npr1 or coi1/NahG backgrounds. These observations suggest that RPP7 initiates resistance through a novel signaling pathway that functions independently of salicylic acid accumulation or jasmonic acid response components.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis/genética , Proteínas de Unión al ADN/genética , Proteínas Fúngicas/genética , Oomicetos/patogenicidad , Enfermedades de las Plantas/genética , Proteínas Quinasas , Proteínas de Saccharomyces cerevisiae , Ácido Salicílico/metabolismo , Factores de Transcripción/genética , Arabidopsis/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas Fúngicas/metabolismo , Mutagénesis , Plantas Modificadas Genéticamente , Transducción de Señal , Factores de Transcripción/metabolismo
4.
Trends Biochem Sci ; 25(2): 79-82, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10664588

RESUMEN

Complementary biochemical and genetic approaches are being used to dissect the signaling network that regulates the innate immune response in plants. Receptor-mediated recognition of invading pathogens triggers a signal amplification loop that is based on synergistic interactions between nitric oxide, reactive oxygen intermediates and salicylic acid. Alternative resistance mechanisms in Arabidopsis are deployed against different types of pathogens; these mechanisms are mediated by either salicylic acid or the growth regulators jasmonic acid and ethylene.


Asunto(s)
Plantas/inmunología , Plantas/metabolismo , Transducción de Señal , Óxido Nítrico/metabolismo , Oxígeno/metabolismo , Plantas/genética , Especies Reactivas de Oxígeno , Ácido Salicílico/metabolismo
5.
J Am Stat Assoc ; 94(445): 64-74, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12155404

RESUMEN

"This article uses a unique set of pooled cross-sectional and time series data to examine the annual rate of U.S. immigration during 1972-1991 from 60 source countries. One distinguishing feature of the article is that it breaks out and cross-classifies various classes of immigrants--numerically limited versus numerically exempt and new immigrant versus adjustment of status. A second distinguishing feature is that it utilizes a unique vector of variables relating to the presence and characteristics of various social programs in source countries. The models developed here emphasize the importance of both differential economic advantage and the ease with which a prospective migrant can transfer skills to the U.S. labor market. Hausman-Taylor instrumental variable estimates of the coefficients indicate that in addition to other factors, social programs in source countries are significant determinants of immigration to the USA." Data are from the Immigration and Naturalization Service's Public Use Files.


Asunto(s)
Emigración e Inmigración , Bienestar Social , Factores Socioeconómicos , Américas , Demografía , Países Desarrollados , Economía , América del Norte , Población , Dinámica Poblacional , Migrantes , Estados Unidos
6.
Proc Natl Acad Sci U S A ; 95(26): 15843-8, 1998 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-9861058

RESUMEN

Plant disease resistance (R) genes confer race-specific resistance to pathogens and are genetically defined on the basis of intra-specific functional polymorphism. Little is known about the evolutionary mechanisms that generate this polymorphism. Most R loci examined to date contain alternate alleles and/or linked homologs even in disease-susceptible plant genotypes. In contrast, the resistance to Pseudomonas syringae pathovar maculicola (RPM1) bacterial resistance gene is completely absent (rpm1-null) in 5/5 Arabidopsis thaliana accessions that lack RPM1 function. The rpm1-null locus contains a 98-bp segment of unknown origin in place of the RPM1 gene. We undertook comparative mapping of RPM1 and flanking genes in Brassica napus to determine the ancestral state of the RPM1 locus. We cloned two B. napus RPM1 homologs encoding hypothetical proteins with approximately 81% amino acid identity to Arabidopsis RPM1. Collinearity of genes flanking RPM1 is conserved between B. napus and Arabidopsis. Surprisingly, we found four additional B. napus loci in which the flanking marker synteny is maintained but RPM1 is absent. These B. napus rpm1-null loci have no detectable nucleotide similarity to the Arabidopsis rpm1-null allele. We conclude that RPM1 evolved before the divergence of the Brassicaceae and has been deleted independently in the Brassica and Arabidopsis lineages. These results suggest that functional polymorphism at R gene loci can arise from gene deletions.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis/genética , Brassica/genética , Genes de Plantas , Proteínas de Plantas/genética , Alelos , Secuencia de Aminoácidos , Arabidopsis/microbiología , Secuencia de Bases , Evolución Biológica , Brassica/microbiología , Clonación Molecular , Secuencia de Consenso , Ligamiento Genético , Genotipo , Inmunidad Innata/genética , Datos de Secuencia Molecular , Proteínas de Plantas/biosíntesis , Proteínas de Plantas/química , Polimorfismo Genético , Pseudomonas/patogenicidad , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico
7.
Plant Cell ; 10(11): 1861-74, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9811794

RESUMEN

Pathogen resistance (R) genes of the NBS-LRR class (for nucleotide binding site and leucine-rich repeat) are found in many plant species and confer resistance to a diverse spectrum of pathogens. Little is known about the mechanisms that drive NBS-LRR gene evolution in the host-pathogen arms race. We cloned the RPP8 gene (for resistance to Peronospora parasitica) and compared the structure of alleles at this locus in resistant Landsberg erecta (Ler-0) and susceptible Columbia (Col-0) accessions. RPP8-Ler encodes an NBS-LRR protein with a putative N-terminal leucine zipper and is more closely related to previously cloned R genes that confer resistance to bacterial pathogens than it is to other known RPP genes. The RPP8 haplotype in Ler-0 contains the functional RPP8-Ler gene and a nonfunctional homolog, RPH8A. In contrast, the rpp8 locus in Col-0 contains a single chimeric gene, which was likely derived from unequal crossing over between RPP8-Ler and RPH8A ancestors within a Ler-like haplotype. Sequence divergence among RPP8 family members has been accelerated by positive selection on the putative ligand binding region in the LRRs. These observations indicate that NBS-LRR molecular evolution is driven by the same mechanisms that promote rapid sequence diversification among other genes involved in non-self-recognition.


Asunto(s)
Arabidopsis/genética , Arabidopsis/microbiología , Evolución Molecular , Genes de Plantas , Oomicetos/patogenicidad , Recombinación Genética , Alelos , Secuencia de Aminoácidos , Secuencia de Bases , Mapeo Cromosómico , ADN de Plantas/genética , Prueba de Complementación Genética , Datos de Secuencia Molecular , Mutación , Fenotipo , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Selección Genética , Homología de Secuencia de Aminoácido
8.
Plant Mol Biol ; 33(1): 125-39, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9037165

RESUMEN

ACT11 represents a unique and ancient actin subclass in the complex Arabidopsis actin gene family. We have isolated and characterized the Arabidopsis ACT11 actin gene and examined its expression. Southern blotting with a 5' gene-specific probe showed that ACT11 was a single-copy gene in the genome. Northern analysis with a 3' gene-specific probe and reverse transcriptase-mediated PCR (RT-PCR) using gene-specific primers detected ACT11 mRNA at low levels in seedling, root, leaf, and silique tissue; at moderate levels in the inflorescence stem and flower; and at very high levels in pollen. The 5' region of the ACT11 gene, including the promoter region, the 5'-untranslated leader, the intron within the leader, and the first 19 actin codons, was fused to a beta-glucuronidase (GUS) reporter gene. The expression of the ACT11/GUS fusion was examined histochemically in numerous independent transgenic Arabidopsis plants. Strong ACT11/GUS activity was detected in rapidly elongating tissues and organs (e.g., etiolated hypocotyls, expanding leaves, stems) and in floral organ primordia. As the floral buds developed into mature flowers, strong GUS activity was gradually restricted to mature pollen and developing ovules. ACT11 appears to be the only Arabidopsis actin gene expressed at significant levels in ovule, embryo, and endosperm. The unique expression patterns in reproductive organs and the sequence divergence of the ACT11 actin gene suggest that the ACT11 isovariant plays distinct and required roles during Arabidopsis development.


Asunto(s)
Actinas/biosíntesis , Arabidopsis/fisiología , Actinas/genética , Secuencia de Aminoácidos , Arabidopsis/genética , Secuencia de Bases , Cartilla de ADN , Oscuridad , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Glucuronidasa/biosíntesis , Luz , Datos de Secuencia Molecular , Familia de Multigenes , Filogenia , Hojas de la Planta , Plantas Modificadas Genéticamente , Polen , Reacción en Cadena de la Polimerasa , Biosíntesis de Proteínas , Proteínas Recombinantes de Fusión/biosíntesis , Semillas
9.
Plant J ; 10(2): 189-202, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8771777

RESUMEN

Plants contain complex actin gene families composed of several diverse and ancient subclasses of genes. One Arabidopsis actin gene subclass represented by the ACT4 and ACT12 genes has been isolated and characterized. Both actin genes have typical plant actin gene structures, including three small introns interrupting the coding region and an intron within the mRNA leader. Their encoded proteins differ from each other in only one amino acid, whereas they differ in 3-10% of their amino acids from the other five Arabidopsis actin subclasses. They also share a few small blocks of DNA sequence homology in the 5' flanking region near their TATA boxs, but not in their introns, 3' flanking regions, or degenerate positions within codons. Southern analysis with gene-specific probes from 5' flanking sequences showed that both were single copy genes in the genome. Both RNA gel blot analysis with 3' gene-specific probes and reverse transcriptase-mediated polymerase chain reactions (RT-PCR) with gene-specific primers detected low levels of ACT4 and ACT12 mRNAs in flowers and very high levels in pollen. The RT-PCR detected very low levels of these mRNAs in the vegetative organs. The 5' region from both genes, including the promoter region, TATA box, the sequence for the mRNA leader and its intron, and the first 19 actin codons, was fused to a beta-glucuronidase (GUS) reporter gene. Expression of the GUS fusions were examined histochemically in 40 independent transgenic Arabidopsis plants. Expression of the ACT4/GUS fusion was restricted to young vascular tissues, tapetum, and developing and mature pollen. Similar expression patterns in these tissues and cell types were observed for ACT12/GUS fusion, yet unlike ACT4, ACT12 was also strongly expressed in the root cap and in a ring of pericycle tissues during lateral root initiation and early development. The unique expression patterns of the ACT4/ACT12 actin gene subclass are discussed in light of recent data on the other expressed members of the Arabidopsis actin gene family.


Asunto(s)
Actinas/genética , Arabidopsis/genética , Genes de Plantas , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Secuencia de Bases , Clonación Molecular , Secuencia Conservada , ADN de Plantas/genética , Regulación de la Expresión Génica de las Plantas , Genes Reporteros , Genoma de Planta , Glucuronidasa/genética , Intrones , Datos de Secuencia Molecular , Familia de Multigenes , Plantas Modificadas Genéticamente , Polen/genética , Polen/crecimiento & desarrollo , Polen/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN de Planta/genética , ARN de Planta/metabolismo , Homología de Secuencia de Ácido Nucleico , Distribución Tisular
10.
Plant Physiol ; 111(3): 699-711, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8754679

RESUMEN

ACT7 encodes one of the six distinct and ancient subclasses of actin protein in the complex Arabidopsis actin gene family. We determined the sequence and structure of the Arabidopsis thaliana ACT7 actin gene and investigated its tissue-specific expression and regulation. The ACT7 mRNA levels varied by 128-fold among several different tissues and organs. The highest levels of aCT7 mRNA were found in rapidly expanding vegetative organs, the lowest in pollen. A translational fusion with the 5' end of ACT 7 (1.9 kb) joined to the beta-glucuronidase reporter gene was strongly and preferentially expressed in all young, developing vegetative tissues of transgenic Arabidopsis plants. ACT7 was the only Arabidopsis actin gene strongly expressed in the hypocotyl and seed coat. Although no beta-glucuronidase expression was seen in developing ovules or immature seeds, strong expression was seen in dry seeds and immediately after imbibition in the entire seedling. ACT7 was the only Arabidopsis actin gene to respond strongly to auxin, other hormone treatments, light regime, and wounding, and may be the primary actin gene responding to external stimuli. The ACT7 promoter sequence contains a remarkable number of motifs with sequence similarity to putative phytohormone response elements.


Asunto(s)
Actinas/biosíntesis , Arabidopsis/fisiología , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Reguladores del Crecimiento de las Plantas/farmacología , Actinas/genética , Secuencia de Aminoácidos , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Secuencia de Bases , Cartilla de ADN , Exones , Biblioteca de Genes , Genes de Plantas , Glutatión Transferasa , Datos de Secuencia Molecular , Familia de Multigenes , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes de Fusión/biosíntesis , TATA Box , Transcripción Genética/efectos de los fármacos
11.
Plant J ; 10(1): 107-21, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8758981

RESUMEN

Arabidopsis has a complex and ancient actin gene family encoding six divergent subclasses of proteins. One subclass is represented by ACT2 and ACT8, which encode nearly identical proteins. These two genes differ significantly in flanking and intron sequences and in silent nucleotide positions within codons. Gene-specific RNA gel blot hybridization and reverse transcriptase-mediated polymerase chain reaction (RT-PCR) assays showed that ACT2 and/or ACT8mRNAs were coordinately and strongly expressed in leaves, roots, stems, flowers, pollen, and siliques. Together they account for greater than 80% of the actin mRNA in most Arabidopsis organs. The 5' flanking regions, including the promoter, the mRNA leader exon, an intron in the mRNA leader, and the first 19 codons, were coupled to a beta-glucuronidase (GUS) reporter gene and transformed into Arabidopsis. The ACT2/GUS construct was expressed strongly in nearly all the vegetative tissues in seedlings, juvenile plants, and mature plants. These activities persisted in older tissues. Little or no expression was observed in seed coats, hypocotyls, gynoecia, or pollen sacs. In contrast, the expression of the ACT8/GUS construct was weaker. It was observed only in a subset of the organs and tissues expressing ACT2/GUS and was not significantly expressed in the flower. ACT2, ACT8, and ACT8/GUS mRNAs were present at moderate to high levels in pollen, and yet neither ACT2/GUS nor ACT8/GUS enzyme expression could be detected in pollen. This suggested a mechanism of translational control affecting ACT2 and ACT8 expression in some tissues. The conservation of protein sequence and overlapping patterns of expression, in spite of significant DNA sequence divergence, suggests that the function and regulation of these two genes have been conserved during the evolution of the Brassicaceae.


Asunto(s)
Actinas/genética , Arabidopsis/genética , Actinas/clasificación , Secuencia de Aminoácidos , Arabidopsis/metabolismo , Secuencia de Bases , ADN de Plantas/genética , Expresión Génica , Genes de Plantas , Genes Reporteros , Datos de Secuencia Molecular , Familia de Multigenes , Plantas Modificadas Genéticamente , Biosíntesis de Proteínas , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN de Planta/genética , ARN de Planta/metabolismo , Homología de Secuencia de Ácido Nucleico , Distribución Tisular
12.
Curr Biol ; 6(6): 634-7, 1996 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-8793280

RESUMEN

Recent studies suggest that plant disease-resistance responses use multiple signaling pathways acting subsequent to pathogen recognition, and that phosphorylation cascades play a prominent role in the recognition and execution of foreign invaders.


Asunto(s)
Proteínas de Arabidopsis , Genes de Plantas , Enfermedades de las Plantas , Plantas/genética , Transducción de Señal/genética , Proteínas de Plantas/genética , Plantas/inmunología
13.
Plant Physiol ; 111(1): 115-26, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8685262

RESUMEN

Profilin is a ubiquitous eukaryotic protein that regulates the actin cytoskeleton and recently has been identified as a potent allergen in pollen. We examined the profilin gene family in the model plant, Arabidopsis thaliana, and found that it contained approximately 8 to 10 members. Four distinct profilin sequences, three cDNAs, PRF1, PRF2, and PRF3, and two genomic clones, PRF1 and PRF4, were isolated and characterized. These genes encoded four distinct profilin isoforms of 131 to 134 amino acids. Northern and reverse-transcriptase polymerase chain reaction analyses demonstrated that Arabidopsis PRF1 was expressed in all major plant organs, whereas PRF4 was specifically expressed in mature pollen. Gene trees constructed from amino acid sequence data revealed the presence of two ancient, distinct profilin gene classes in plants. PRF4 was in a class with previously identified pollen-specific profilins from monocot and dicot species. PRF1, PRF2, PRF3, and a distant dicot sequence formed a separate novel class, suggesting an ancient separation of plant profilins based on regulation and perhaps function. The coevolution of plant actin and profilin classes with similar patterns of expression is discussed. The similarity of plant, fungal, protist, insect, and nematode profilins and their extreme divergence from the vertebrate profilins has striking implications for the evolution of fungal-spore- and plant-pollen-profilins as allergens.


Asunto(s)
Arabidopsis/genética , Proteínas Contráctiles , Proteínas de Microfilamentos/genética , Familia de Multigenes , Alérgenos/genética , Secuencia de Aminoácidos , Proteínas de Arabidopsis , Secuencia de Bases , Evolución Biológica , Southern Blotting , Secuencia Conservada , ADN Complementario , Genes de Plantas , Datos de Secuencia Molecular , Profilinas , Homología de Secuencia de Aminoácido
14.
Genetics ; 142(2): 587-602, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8852856

RESUMEN

Higher plants contain families of actin-encoding genes that are divergent and differentially expressed. Progress in understanding the functions and evolution of plant actins has been hindered by the large size of the actin gene families. In this study, we characterized the structure and evolution of the actin gene family in Arabidopsis thaliana. DNA blot analyses with gene-specific probes suggested that all 10 of the Arabidopsis actin gene family members have been isolated and established that Arabidopsis has a much simpler actin gene family than other plants that have been examined. Phylogenetic analyses suggested that the Arabidopsis gene family contains at least two ancient classes of genes that diverged early in land plant evolution and may have separated vegetative from reproductive actins. Subsequent divergence produced a total of six distinct subclasses of actin, and five showed a distinct pattern of tissue specific expression. The concordance of expression patterns with the phylogenetic structure is discussed. These subclasses appear to be evolving independently, as no evidence of gene conversion was found. The Arabidopsis actin proteins have an unusually large number of nonconservative amino acid substitutions, which mapped to the surface of the actin molecule, and should effect protein-protein interactions.


Asunto(s)
Actinas/genética , Arabidopsis/genética , Genoma de Planta , Proteínas de Plantas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Evolución Biológica , Cartilla de ADN , Variación Genética , Datos de Secuencia Molecular , Filogenia
15.
Plant Cell ; 8(1): 15-30, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8597657

RESUMEN

We have proposed that ancient and divergent classes of plant actin genes have been preserved throughout vascular plant evolution, because they have distinct patterns of gene regulation. The hypothesis was explored for ACT1 and ACT3, which represent one of the six ancient subclasses in the Arabidopsis actin gene family. Comparison of ACT1 and ACT3 cDNA and genomic sequences revealed highly divergent flaking and intron sequences, whereas they encoded nearly identical proteins. Quantification of their level of divergence suggests that they have not shared a common ancestor for 30 to 60 million years. Gene-specific RNA gel blot hybridization and reverse transcriptase-polymerase chain reaction analyses demonstrated that the distribution of ACT1 and ACT3 mRNAs was very similar: both preferentially accumulated at high levels in mature pollen and at very low levels in the other major organs. The 5' flanking regions of both genes, including the promoter, leader exon and intron, and the first 19 condons, were fused to the beta-glucuronidase (GUS) reporter gene. The expression of these reporter fusions was examined in a large number of transgenic Arabidopsis plants. Histochemical assays demonstrated that both ACT1-GUS and ACT3-GUS constructs were expressed preferentially in pollen, pollen tubes, and in all organ primordia, including those in roots shoots, and the inflorescence. Comparison of the 5' flanking regions of ACT1 and ACT3 revealed a number of short conserved sequences, which may direct their common transcriptional and post-transcriptional regulation. The expression patterns observed were distinct from those of any other other Arabidopsis actin subclass. The conservation of their expression pattern and amino acid sequences suggests that this actin subclass plays a distinct and required role in the plant cytoskeleton.


Asunto(s)
Actinas/genética , Proteínas de Arabidopsis , Arabidopsis/crecimiento & desarrollo , Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Actinas/biosíntesis , Secuencia de Aminoácidos , Secuencia de Bases , Evolución Biológica , Citoesqueleto/fisiología , Genes Reporteros , Biblioteca Genómica , Linfoma no Hodgkin , Modelos Genéticos , Técnicas de Sonda Molecular , Datos de Secuencia Molecular , Proteínas de Plantas/biosíntesis , Raíces de Plantas/crecimiento & desarrollo , Brotes de la Planta/crecimiento & desarrollo , Plantas Modificadas Genéticamente , Polen/crecimiento & desarrollo , Reacción en Cadena de la Polimerasa , ARN Mensajero/análisis , ARN de Planta/análisis , Análisis de Secuencia de ADN , Distribución Tisular , Transcripción Genética , Inmunología del Trasplante
16.
Plant J ; 8(4): 613-22, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7496405

RESUMEN

A method is presented to facilitate the isolation of mutations in plant genes, which requires knowledge of the target gene or protein sequence, and is independent of mutant phenotype. The polymerase chain reaction was used to amplify the junctions between a T-DNA insert and the gene of interest from pools of mutant plant lines. The approach was used to identify mutations in Arabidopsis thaliana actin genes. The Arabidopsis genome encodes 10 actins in six ancient subclasses each with distinct expression patterns. Primers in the T-DNA border and highly degenerate actin primers, designed from conserved amino acid motifs, were used to prime the amplification. The PCR products were transferred to filters and probed for actin at low stringency. Thus, mutations in all 10 actin genes were screened for simultaneously. Mutations in the vegetative constitutive actin gene, ACT2, and the pollen-specific actin gene, ACT4, were identified in a population of 5300 lines containing approximately 1.5 T-DNA insertions per line. The screen was sensitive enough that actin insertion alleles were easily distinguished among pools of 100 plant lines. PCR techniques were used which accelerated the purification of mutant lines, and segregation, physical mapping, and sequencing of the act2-1 and act4-1 mutations. This strategy should be generally useful in screening mutant libraries made with a variety of plant insertion elements for mutations in any known sequence.


Asunto(s)
Actinas/genética , Arabidopsis/genética , ADN Bacteriano/análisis , ADN Bacteriano/genética , Genes de Plantas , Actinas/biosíntesis , Secuencia de Aminoácidos , Arabidopsis/metabolismo , Secuencia de Bases , Cartilla de ADN , Elementos Transponibles de ADN , ADN de Cadena Simple/análisis , Datos de Secuencia Molecular , Mutagénesis Insercional , Plantas Modificadas Genéticamente , Reacción en Cadena de la Polimerasa
17.
Genetics ; 137(3): 743-50, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8088520

RESUMEN

Actin is a major component of the cytoskeleton and one of the most abundant proteins found in eukaryotic cells. Comparative sequence analysis shows that this essential gene has been highly conserved throughout eukaryotic evolution making it useful for phylogenetic analysis. Complete cDNA clones for the actin-encoding gene were isolated and characterized from Pneumocystis carinii purified from immunosuppressed rat lungs. The nucleotide sequence encodes a protein of 376 amino acids. The predicted actin protein of P. carinii shares a high degree of conservation to other known actins. Only one major actin gene was found in P. carinii. The P. carinii actin sequence was compared with 30 other actin sequences. Gene phylogenies constructed using both neighbor-joining and protein parsimony methods places the P. carinii actin sequence closest to the majority of the fungi. Since the phylogenetic relationship of P. carinii to fungi and protists has been questioned, these data on the actin gene phylogeny support the grouping of P. carinii with the fungi.


Asunto(s)
Actinas/genética , Proteínas Fúngicas/genética , Genes Fúngicos , Pneumocystis/clasificación , Pneumocystis/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Secuencia Conservada , Cartilla de ADN , ADN de Hongos/genética , Eucariontes/genética , Masculino , Datos de Secuencia Molecular , Filogenia , Ratas , Ratas Sprague-Dawley
18.
Reg Stud ; 27(4): 351-63, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-12344799

RESUMEN

The authors present a methodology for measuring the magnitude of international migration flows that includes an earnings equation approach as an economic dimension. "Applying our methodology to U.S. immigration, we find considerable variation across source regions in the value of immigrants. Moreover, we find that simply comparing initial earnings without controlling for differences in the characteristics and migration patterns of immigrants from the various source regions can misrepresent the relative earnings potential or value of migrants." (SUMMARY IN FRE AND GER)


Asunto(s)
Economía , Emigración e Inmigración , Geografía , Renta , Métodos , Migrantes , Américas , Demografía , Países Desarrollados , América del Norte , Población , Dinámica Poblacional , Factores Socioeconómicos , Estados Unidos
19.
Connect Tissue Res ; 24(2): 157-68, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2354635

RESUMEN

A number of regulators are available in cartilage to effect the local control of matrix production by chondrocytes. A cartilage slice assay has been used in this study to investigate the influence of such regulators (extracted from foetal cartilage) on intact cartilage. A net inhibition of sulphation was found, rather than stimulation as reported for extracts rich in the somatomedin-like, cartilage derived factor (CDF). Inhibition was due, to a high molecular weight component identified as hyaluronic acid (based on enzyme sensitivity, chromatographic behaviour and temperature stability). Its inhibition of sulphation in intact cartilage was more profound than that produced by commercially available umbilical cord hyaluronate. We conclude that foetal cartilage hyaluronate is a far more potent inhibitor of sulphation than hyaluronate from other sources, suppressing sulphation even in the presence of a somatomedin-like activator and in intact cartilage, which responds poorly to commercial hyaluronate.


Asunto(s)
Cartílago/embriología , Ácido Hialurónico/farmacología , Sulfatos/metabolismo , Animales , Cartílago/análisis , Cartílago/metabolismo , Bovinos , Cromatografía DEAE-Celulosa , Cromatografía en Gel , Humanos , Ácido Hialurónico/aislamiento & purificación , Concentración de Iones de Hidrógeno , Factor I del Crecimiento Similar a la Insulina/farmacología , Peso Molecular
20.
Br J Anaesth ; 60(6): 627-31, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-3377946

RESUMEN

Fifty-seven women received extradural morphine 3 mg, buprenorphine 0.18 mg or buprenorphine 0.09 mg after elective Caesarean section carried out under extradural bupivacaine. Supplementary sublingual buprenorphine was available on demand. Ten-centimetre visual analogue pain scores were completed regularly; emesis, pruritus and urinary retention were recorded for 24 h. Patients who received buprenorphine 0.09 mg had more pain, and required more supplementary analgesia, than those who received morphine 3 mg. Pain scores and analgesic requirements after buprenorphine 0.18 mg were not significantly different from either of the other two groups. Emesis was not significantly different in the three groups. More itching occurred after morphine 3 mg and buprenorphine 0.18 mg than after buprenorphine 0.09 mg; pruritus of the face, legs and perineum was more common after morphine than buprenorphine. Twenty-eight percent of patients without a urinary catheter developed retention of urine. Seventy-five to 84% of patients were satisfied with analgesia during the first day after operation. Analgesia and adverse effects were similar when morphine 3 mg or buprenorphine 0.18 mg was given extradurally after Caesarean section.


Asunto(s)
Buprenorfina/uso terapéutico , Cesárea , Morfina/uso terapéutico , Dolor Postoperatorio/tratamiento farmacológico , Buprenorfina/administración & dosificación , Buprenorfina/efectos adversos , Femenino , Humanos , Inyecciones Epidurales , Morfina/administración & dosificación , Morfina/efectos adversos , Embarazo
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