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1.
Schmerz ; 28(6): 600-6, 2014 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-25179418

RESUMO

BACKGROUND: Physical, sexual and emotional abuse in childhood and adolescence is considered to play a role in the etiology and generalization of chronic pain in adulthood. However, it remains unclear whether abuse is specifically associated with different dimensions of nonspecific chronic low back pain (CLBP) and if these associations are mediated by psychological symptoms. MATERIAL AND METHODS: A total of 103 patients with validated CLBP were assessed by pain drawing, the multidimensional pain questionnaire and the pain experience scale. The childhood trauma questionnaire was used to retrospectively screen for physical, sexual and emotional abuse in childhood and adolescence. Patients were also screened for symptoms of depression, anxiety and dissociation in order to look for possible mediators. RESULTS: Patients with CLBP who reported childhood abuse showed higher pain intensity, higher spatial extent of pain, higher affective and sensory pain sensation and more pain disability compared to CLBP patients who had not experienced abuse. However, multivariate analyses revealed that only the spatial extent of pain was directly associated with childhood abuse. Furthermore, a significant association between childhood abuse and sensory pain sensation was found to be mediated by symptoms of anxiety and dissociation. CONCLUSION: The influence of childhood abuse on CLBP is different for specific pain dimensions; therefore, CLBP should be faced as a complex construct that comprises different dimensions. Childhood abuse is suggested as a risk factor for spreading pain in CLBP persons; therefore, CLBP patients reporting additional pain locations might benefit from diagnostic and therapeutic interventions specific for childhood abuse experiences.


Assuntos
Maus-Tratos Infantis/psicologia , Dor Lombar/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtornos de Ansiedade/diagnóstico , Transtornos de Ansiedade/psicologia , Causalidade , Criança , Maus-Tratos Infantis/diagnóstico , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/psicologia , Transtornos Dissociativos/diagnóstico , Transtornos Dissociativos/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Estudos Retrospectivos , Inquéritos e Questionários
2.
Plant Dis ; 91(10): 1212-1220, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30780511

RESUMO

Viruslike chlorotic ring spot symptoms and line patterns of unknown origin were observed on a greenhouse-grown turnip plant. The suspected virus was mechanically transmissible to plants in the Brassicaceae. Electron microscopic analysis revealed icosahedral particles approximately 28 nm in diameter. Reverse transcriptase-polymerase chain reaction (RT-PCR) analyses suggested that the pathogen is a comovirus, an observation that was confirmed by analysis of portions of the genomic sequence. This virus was provisionally named Turnip ringspot virus (TuRSV). Based on the RNA 1 sequence, TuRSV is most similar to Radish mosaic virus, another pathogen that infects members of the Brassicaceae. Arabidopsis thaliana is susceptible to TuRSV, and 12 out of the 23 ecotypes studied showed symptoms when inoculated with the virus. TuRSV induced a variety of responses on ecotypes from death to no infection. Some ecotypes showed one or two rounds of symptom display followed by recovery when inoculated with TuRSV. About half of the ecotypes (11/23) analyzed showed no symptoms when inoculated with TuRSV. Col-0 plants showed no symptoms, and infectious virus was not recovered from systemic leaves, although it could be detected by RT-PCR. Col-0 plants harboring mutations impairing the ethylene, jasmonic acid, or salicylic acid signaling pathways did not show symptoms when inoculated with TuRSV.

3.
J Theor Biol ; 217(2): 195-201, 2002 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-12202113

RESUMO

The translation of viral mRNAs by host ribosomes is essential for infection. Hence, codon usage of virus genes may influence efficiency of infection. In addition, composition of nucleotides in the third position within codons of genes can reflect evolutionary relationships. In this study, third position codon composition was examined for the seven genes of eight Cauliflower mosaic virus isolates. Genes IV-VII had similar codon composition values and were termed Class 1 genes. Genes I-III possessed corresponding codon composition values and were termed Class 2 genes. The codon composition values of Class 1 and genes differed significantly. Neither Class 1 nor Class 2 genes had codon composition values identical to that of the host plant, Arabidopsis thaliana. However, Class 1 genes possessed codon composition values closer to those of the host than Class 2 genes. Examination of the genomes of three Rous sarcoma virus isolates indicated that codon composition values were similar for the gag, pol, and env genes but these genes differed significantly from the src genes. Since codon composition values for Rous sarcoma virus distinguished a "foreign" gene from the rest of the viral genome, it is possible that the Cauliflower mosaic virus genome is composed of genes from two different sources. Others have suggested that Cauliflower mosaic virus evolved in this manner and our data provide support for this hypothesis.


Assuntos
Caulimovirus/genética , Códon/genética , Evolução Molecular , Genoma Viral , Arabidopsis/genética , Vírus do Sarcoma Aviário/genética , Genes de Plantas , Genes Virais , Análise de Sequência de DNA
4.
J Vet Med A Physiol Pathol Clin Med ; 49(2): 107-12, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11958467

RESUMO

The age, type, etc., time of injury, body areas injured, treatment modalities and mortality rates were reviewed in 185 dogs and 11 cats that were bitten by dogs. Male dogs were more frequently bitten than females, and small dogs (< or = 10 kg) were not only the most common victims but also were more likely to suffer multiple injuries. Mortality occurred only in cases with thoracic or abdominal injuries. Exploratory thoracotomy, performed in some of the cases presented with penetrating thoracic injury, did not prove to alter prognosis. Cats are not as frequently bitten as dogs, and are often younger than the mean age of cats in the overall hospital population.


Assuntos
Mordeduras e Picadas/veterinária , Gatos/lesões , Cães/lesões , Ferimentos Penetrantes/veterinária , Animais , Mordeduras e Picadas/epidemiologia , Mordeduras e Picadas/mortalidade , Mordeduras e Picadas/cirurgia , Desbridamento/veterinária , Feminino , Israel/epidemiologia , Masculino , Registros/veterinária , Estudos Retrospectivos , Ferimentos Penetrantes/epidemiologia , Ferimentos Penetrantes/mortalidade , Ferimentos Penetrantes/cirurgia
5.
J Vet Med A Physiol Pathol Clin Med ; 49(1): 33-7, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11913824

RESUMO

Pulsed electromagnetic fields (PEMFs) have been found to be beneficial to a wide variety of biological phenomena. In particular, PEMFs have been shown to be useful in the promotion of healing of ununited fractures. Conflicting information exists regarding the benefit of using PEMFs to accelerate the healing of fresh fractures. This paper reports on the evaluation of the effect of a new PEMF generator (PAP IMI) on the healing of fresh ulnar fractures in rats. This device is unique by virtue of the extremely high power output of each of the pulses it generates. Ulnar fractures were created in rats by using a bone cutter, thus producing a 2-3 mm bone defect. Rats were then randomly divided into treatment and control groups. The treatment group underwent periodic treatments with the PAP IMI, and the control group received no treatment. Radiographs of rats from both groups were taken at 1-week intervals. Histological evaluation was performed at the end of the study. Radiographic and histopathological evaluations were scored, and scores were used to assess both rate and quality of healing. The radiographic results demonstrated gradual bridging callus formation in both control and treatment groups, however, the healing process was faster in rats that were not treated by PEMF. Histological evaluation demonstrated that the fibrous content of the callus in rats belonging to the treatment group was significantly higher than that in rats belonging to the control group. The results of this study do not support the claim that PEMF generated by the PAP-IMI stimulate osteogenesis and bone healing after the creation of fresh ulnar fractures in rats.


Assuntos
Campos Eletromagnéticos , Consolidação da Fratura , Fraturas da Ulna/terapia , Animais , Modelos Animais de Doenças , Masculino , Radiografia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento , Fraturas da Ulna/diagnóstico por imagem
6.
Phytopathology ; 92(2): 190-6, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18943093

RESUMO

ABSTRACT Arabidopsis thaliana ecotypes vary in their responses to viruses. In this study, we analyzed the variation in response of A. thaliana ecotype Tsu-0 to Cauliflower mosaic virus (CaMV). This ecotype was previously reported to be resistant to two CaMV isolates (CM1841 and CM4-184), but susceptible to W260. In this study, we show that Tsu-0 is resistant to four additional CaMV isolates. CaMV propagated within the rosette leaves of Tsu-0 plants, but did not appear to spread systemically into the inflorescence. However, virus viability in rosette leaves of Tsu-0 plants apparently was not compromised because infectious CaMV could be recovered from these organs. W260 overcomes Tsu-0 resistance by a passive mechanism (i.e., this virus avoids activating plant defenses). The portion of the viral genome responsible for W260 resistance breakage was mapped to the 5' third of gene VI, which we have termed RBR-1. This region is also responsible for controlling the ability of CaMV to infect different types of solanaceous plants. Hence, the pathways by which plants of different families interact with CaMV may be conserved through evolution.

7.
Biochem Biophys Res Commun ; 245(2): 403-6, 1998 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-9571163

RESUMO

DNA sequences present in multiple copies in plant genomes are often methylated. However, it was not known if methylation occurs on multiple copy DNA molecules that are not integrated into the plant genome. To investigate this possibility, the methylation state of cauliflower mosaic virus [CaMV] DNA was studied in inoculated turnip leaves at different days post-inoculation [DPI]. Unencapsidated CaMV DNA was found in an unmethylated state up to 7 DPI. By 9 DPI, viral DNA was methylated at almost all HpaII/MspI sites within the CaMV genome. DNA methylation did not appear to be preferential but occurred at almost all HpaII/MspI sites at approximately the same time. Methylation appeared to occur in an all or none manner, suggestive of a switch mechanism. These data strongly suggest that copy number-dependent methylation occurs on DNA molecules that are not integrated into the genome of a host cell.


Assuntos
Dosagem de Genes , Genes de Plantas/genética , Brassica/genética , Caulimovirus/genética , Metilação de DNA , DNA de Plantas/genética , DNA Viral/genética , Desoxirribonuclease HpaII/metabolismo , Fatores de Tempo , Transfecção/genética
8.
Phytopathology ; 87(8): 792-8, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18945046

RESUMO

ABSTRACT Arabidopsis thaliana ecotype En-2 was previously shown to be resistant to cauliflower mosaic caulimovirus (CaMV) isolate CM4-184. In this study, En-2 plants were screened with eight other isolates of CaMV to identify viruses capable of overcoming resistance and to determine if the mechanism of resistance was the same for each virus. En-2 resistance to most CaMV isolates was mediated by the same mechanism, i.e., preventing virus long-distance movement. One CaMV isolate, NY8153, was found that produced a severe systemic infection on En-2 plants. In addition, the CM1841 isolate was able to spread systemically through En-2 plants, to a limited extent, without producing visible symptoms. These data indicate that the resistance shown by En-2 plants is not an all-or-none phenomenon. En-2 plants were susceptible to turnip mosaic potyvirus, suggesting that resistance is specific to CaMV.

9.
Bioessays ; 15(11): 741-8, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8292004

RESUMO

Recent progress in the study of short-distance (cell-to-cell) movement of plant virus, facilitated by 'movement proteins', has led to a resurgence of interest in long-distance virus transport in the phloem. Relatively little is known about phloem-specific barriers to virus movement or about the form in which virus enters, travels within and exists this tissue. Progress in understanding virus and photoassimilate transport is limited by a paucity of information on the substructure and properties of plasmodesmata at specific interfaces. The direction of virus movement, once it has entered the phloem, can be understood by following photoassimilate translocation, a complex and dynamic process influenced by plant growth, development and vascular topology.


Assuntos
Fenômenos Fisiológicos Vegetais , Vírus de Plantas/fisiologia , Microscopia Eletrônica , Plantas/microbiologia , Plantas/ultraestrutura
10.
Trends Microbiol ; 1(8): 314-7, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8162417

RESUMO

During systemic infections, plant viruses move long distances through the plant vasculature. Leaf age, the rate of plant development, plant anatomy and the direction of nutrient flow in the vasculature influence the pattern and extent of systemic spread of the virus, and, in turn, these factors are major determinants of virus resistance.


Assuntos
Vírus de Plantas/fisiologia , Plantas/microbiologia , Movimento
11.
Plant Cell ; 5(2): 191-202, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8453301

RESUMO

During systemic infections, viruses move long distances through the plant vascular system. The long-distance movement of cauliflower mosaic virus (CaMV) in Arabidopsis has been examined using a whole plant in situ hybridization technique called plant skeleton hybridization. CaMV moves long distance through the phloem largely following the flow of photoassimilates from source to sink leaves. During the course of plant development, sink-source relationships change and the region of the plant that CaMV can invade is progressively reduced. In Arabidopsis, we have found that conditions that influence the rate of plant development dramatically impact the long-distance movement of CaMV, because under normal conditions the rate of plant development is closely matched to the kinetics of virus movement. Ecotypes and mutants of Arabidopsis that flower early show a form of resistance to systemic CaMV infection, which we call "developmental resistance." Developmental resistance results from the fact that the rosette leaves mature early in the life of an early flowering plant and become inaccessible to virus. On the other hand, if the development of early flowering plants is retarded by suboptimal growth conditions, inoculated plants appear more susceptible to the virus and systemic infections become more widespread. We have found that other Arabidopsis ecotypes, such as Enkheim-2 (En-2), show another form of resistance to virus movement that is not based on developmental or growth conditions. The virus resistance in ecotype En-2 is largely conditioned by a dominant trait at a single locus.


Assuntos
Arabidopsis/microbiologia , Vírus do Mosaico/fisiologia , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Hibridização In Situ , Vírus do Mosaico/genética , Vírus do Mosaico/patogenicidade , Movimento , Virulência/genética
12.
Plant Cell ; 4(4): 451-61, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1498603

RESUMO

Both cytokinin (N6-benzyladenine [BA]) and auxin (2,4-dichlorophenoxyacetic acid [2,4-D]) stimulate the accumulation of an mRNA, represented by the cDNA pLS216, in Nicotiana plumbaginifolia suspension culture cells. The kinetics of RNA accumulation were different for the two hormones; however, the response to both was transient, and the magnitude of the response was dose dependent. Runoff transcription experiments demonstrated that the transient appearance of the RNA could be accounted for by feedback regulation of transcription and not by the induction of an RNA degradation system. The feedback mechanism appeared to desensitize the cells to further exposure of the hormone. In particular, cells became refractory to the subsequent addition of 2,4-D after the initial RNA accumulation response subsided. A very different response was observed when the second hormone was added to cells that had been desensitized to the first hormone. Under such conditions, BA produced a heightened response in cells desensitized to 2,4-D and vice versa. These findings support a model in which cytokinin further enhances the auxin response or prevents its feedback inhibition. The hormone-induced RNA accumulation was blocked by the protein kinase inhibitor staurosporin. On the other hand, the protein phosphatase inhibitor okadaic acid stimulated expression, and, in particular, okadaic acid was able to stimulate RNA accumulation in cells desensitized to auxin. This suggests that hormone activation involves phosphorylation of critical proteins on the hormone signaling pathway, whereas feedback inhibition may involve dephosphorylation of these proteins. The sequence of pLS216 is similar to genes in other plants that are stimulated by multiple agonists such as auxins, elicitors, and heavy metals, and to the gene encoding the stringent starvation protein in Escherichia coli. It is proposed that this gene family in various plants be called multiple stimulus response (msr) genes.


Assuntos
Citocininas/fisiologia , Regulação da Expressão Gênica , Ácidos Indolacéticos/fisiologia , Nicotiana/genética , Proteínas de Plantas/genética , Plantas Tóxicas , Sequência de Aminoácidos , Sequência de Bases , Células Cultivadas , DNA , Retroalimentação , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Cinética , Dados de Sequência Molecular , Fosforilação , Proteínas de Plantas/metabolismo
13.
Plant Cell ; 1(9): 925-36, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2535532

RESUMO

It is known that a 16-base pair palindrome (ACGTAAGCGCTTACGT) located upstream of the ocs gene can activate a maize adh1 promoter in a transient expression system [Ellis et al. (1987). EMBO J. 6, 11-16; Ellis et al. (1987). EMBO J. 6, 3203-3208]. We have determined that this palindrome is also essential for ocs promoter activity in tobacco calli. In addition, sequences immediately adjacent to this palindrome, both 5' and 3', modulate its activity. The palindrome is sensitive to the differentiated state of the plant cells in which it resides; it is active in calli and the leaves of small shoots but is inactive in the leaves of rooted plants. We have tested upstream sequences from two other T-DNA genes that have homology to this palindrome for their ability to activate the octopine synthase promoter in tobacco calli. The upstream region from the mannopine synthase gene can activate the octopine synthase promoter, but an upstream region from the gene implicated in octopine and nopaline secretion cannot activate the promoter.


Assuntos
Aminoácido Oxirredutases/genética , Sequências Reguladoras de Ácido Nucleico , Agrobacterium tumefaciens/genética , Aminoácido Oxirredutases/metabolismo , Sequência de Bases , Clonagem Molecular , DNA , Dados de Sequência Molecular , Plantas Tóxicas , Plasmídeos , Mapeamento por Restrição , Homologia de Sequência do Ácido Nucleico , Nicotiana
14.
Proc Natl Acad Sci U S A ; 85(8): 2553-7, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3357881

RESUMO

We have identified a transcriptional activating element within the 5' flanking sequence of the Agrobacterium tumefaciens octopine synthase (ocs) gene that is necessary for ocs expression in transformed tobacco calli. This element is located between 333 and 116 base pairs upstream from the transcription initiation site and functions independent of orientation when placed upstream of the ocs gene. It does not function in either orientation when placed downstream of the gene, nor can it activate its promoter when separated by a distance of 608 base pairs. Deletion analysis indicates that sequences essential for activator function are localized between 222 and 177 base pairs upstream of the transcription initiation site. Another region, located between 333 and 249 base pairs upstream of the transcription initiation site, does not as a monomer activate the ocs promoter, but it can as a dimer.


Assuntos
Aminoácido Oxirredutases/genética , Sequências Reguladoras de Ácido Nucleico , Sequência de Bases , Dados de Sequência Molecular , Oxirredutases atuantes sobre Doadores de Grupo CH-NH , Plantas/genética , Regiões Promotoras Genéticas , Rhizobium/genética , Transcrição Gênica
15.
Plant Physiol ; 78(3): 510-3, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16664274

RESUMO

The biosynthesis of cytokinins was examined in pea (Pisum sativum L.) plant organs and carrot (Daucus carota L.) root tissues. When pea roots, stems, and leaves were grown separately for three weeks on a culture medium containing [8-(14)C]adenine without an exogenous supply of cytokinin and auxin, radioactive cytokinins were synthesized by each of these organs. Incubation of carrot root cambium and noncambium tissues for three days in a liquid culture medium containing [8-(14)C]adenine without cytokinin demonstrates that radioactive cytokinins were synthesized in the cambium but not in the noncambium tissue preparation. The radioactive cytokinins extracted from each of these tissues were analyzed by Sephadex LH-20 columns, reverse phase high pressure liquid chromatography, paper chromatography in various solvent systems, and paper electrophoresis. The main species of cytokinins detectable by these methods are N(6)-(Delta(2)-isopentyl_adenine-5'-monophosphate, 6-(4-hydroxy-3-methyl-2-butenyl-amino)-9-beta-ribofuranosylpurine-5'- monophosphate, N(6)-(Delta(2)-isopentenyl)adenosine, 6-(4-hydroxy-3-methyl-2-butenylamino)-9-beta-ribofuranosylpurine, N(6)-(Delta(2)-isopentenyl)adenine, and 6-(4-hydroxy-3-methyl-2-butenylamino)purine. On the basis of the amounts of cytokinin synthesized per gram fresh tissues, these results indicate that the root is the major site, but not the only site, of cytokinin biosynthesis. Furthermore, cambium and possibly all actively dividing tissues are responsible for the synthesis of this group of plant hormones.

16.
Plant Physiol ; 77(1): 99-103, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16664037

RESUMO

Comparison of two-dimensional polyacrylamide gel electrophoretic maps of proteins isolated from benzyladenine-treated and untreated pumpkin (Cucurbita pepo L. cv Halloween) cotyledons showed that the expression of certain proteins is enhanced, induced, or suppressed by the cytokinin treatment. The amount of poly(A)(+) mRNA isolated from cotyledons incubated with 10(-4) molar benzyladenine for five days was about four-fold over the water-incubated control. The activity of hydroxypyruvate reductase prepared from purified cotyledonous microbodies and analyzed by native gel electrophoresis is proportionally enhanced by sequentially higher concentrations (10(-9) to 10(-4) molar) of benzyladenine. Ethidium bromide (1 microgram per milliliter) did not inhibit hydroxypyruvate reductase activity; thus, the enzyme synthesis does not appear to be controlled by organelle genes. Hydroxypyruvate reductase synthesis is inhibited by cycloheximide, cordycepin, and to a certain degree by actinomycin D. These data support the view of a close association between cytokinin action and gene expression.

17.
Plant Physiol ; 75(2): 442-6, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16663640

RESUMO

N(6)-(Delta(2)-isopentenyl)Adenine and N(6)-(Delta(2)-isopentenyl)adenosine were hydroxylated, respectively, to 6-(4-hydroxy-3-methyl-trans-2-butenylamino)purine and 6-(4-hydroxy-3-methyl-trans-2-butenylamino) -9-beta-ribofuranosylpurine in the presence of NADPH and the microsomal fraction from cauliflowers (Brassica oleracea L.). The hydroxylating reaction was completely inhibited by 10 millimolars metyrapone and partially inactivated by 10-minute treatment of the microsomal preparation with ethylene. The cytokinins were also dealkylated by the microsomal enzymes and formed adenine from cytokinin base and adenosine from cytokinin nucleoside. These results suggest that plant cytochrome P-450 is involved in the conversion of one type of cytokinin to another, and in the modification of cytokinin molecules.

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