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1.
Rev. bras. plantas med ; 15(1): 78-85, 2013. ilus, tab
Artigo em Português | LILACS | ID: lil-669539

RESUMO

O objetivo deste trabalho foi avaliar o efeito da aplicação de diferentes doses de nitrogênio no solo e de épocas de coleta sobre a eficiência nutricional do nitrogênio e a produção de biomassa em Calendula officinalis L. (Asteraceae) em condições de casa de vegetação. O substrato utilizado foi a camada de 0 - 20 cm de Latossolo Vermelho Distroférrico. O delineamento experimental foi inteiramente casualizado, com quatro repetições. Os tratamentos foram constituídos de quatro doses de N (0, 21, 42 e 84mg dm-3) e cinco épocas de colheita (15, 30, 45, 60 e 90 dias após o transplante). O teor de N na inflorescência de calêndula reduziu com as épocas de coleta, redução essa que ocorreu possivelmente devido à menor eficiência da absorção desse elemento pela planta e menor translocação do N para as inflorescências. Pode se concluir que as épocas de avaliação influenciaram na resposta da planta à eficiência de absorção (EFA), sendo a máxima EFA de N aos 51 dias após o transplante das mudas. Observou-se aumento na translocação de N da parte aérea (folhas e caules) para as inflorescências, tendo como consequência a redução do N na parte aérea. Houve incremento na produção de biomassa de calêndula em função das épocas de coleta , e do aumento das doses de N aplicadas no solo. A eficiência nutricional do N foi influenciada pelas épocas de avaliação e pelo teor de N presente no solo.


The aim of this study was to evaluate the effect of both the application of different nitrogen levels on the soil and the harvest periods on nitrogen nutritional efficiency and biomass production in Calendula officinalis L. (Asteraceae) under greenhouse conditions. The employed substrate was 0-20cm layer of Oxisol. Experimental design was completely randomized, with four replicates. Treatments consisted of four N levels (0, 21, 42 and 84 mg dm-3) and five harvest periods (15, 30, 45, 60 and 90 days after transplanting). N levels in Calendula officinalis inflorescences reduced with the harvest periods, and such a reduction was probably due to the lower efficiency of absorption of this element by the plant and to the lower N translocation to inflorescences. We can conclude that the evaluation periods influenced the response of plants to uptake efficiency (UE), and the maximal UE for N was found at 51 days after transplanting of seedlings. There was an increase in N translocation from the shoot (leaves and stems) to inflorescences, which has as consequence N reduction in the shoot. Calendula officinalis biomass production increased with the harvest periods and with the increase in the N levels applied on the soil. N nutritional efficiency was influenced by both the evaluation periods and the N levels present on the soil.


Assuntos
Calendula , Nitrogênio/efeitos adversos , Biomassa , Eficiência/classificação
2.
Rev. bras. plantas med ; 14(2): 255-260, 2012. ilus, tab
Artigo em Português | LILACS | ID: lil-650663

RESUMO

Tendo como objetivo avaliar a eficiência de absorção, translocação e uso de nitrogênio (N) e fósforo (P) pela Pfaffia glomerata, foi conduzido o presente trabalho em casa de vegetação no delineamento inteiramente casualizado com três repetições. Os tratamentos foram dispostos em esquema fatorial 5 x 5, sendo cinco doses de N (0, 125, 250, 375 e 500 mg vaso-1) e cinco doses de P (P2O5) (0, 125, 250, 375 e 500 mg vaso-1). Os resultados evidenciaram que a eficiência de absorção de N e P foi influenciada pelas doses de N e P utilizadas no experimento apresentando interação entre os fatores em estudo. A eficiência de translocação do N foi consideravelmente menor que a de P, provavelmente pela maior concentração de compostos nitrogenados nas raízes em detrimento da parte aérea. Observou-se maior eficiência de uso do P devido à menor concentração desse elemento na planta. A absorção de N e de P foi influenciada pela dose desses elementos no solo, sendo possível a estimativa das doses desses nutrientes que proporcionem maiores eficiências de absorção, translocação, uso e teor total.


Aimed at evaluating the efficiency of nitrogen (N) and phosphorus (P) uptake, translocation and use by Pfaffia glomerata, the present study was conducted in greenhouse, in completely randomized design with three replicates. Treatments were displayed in 5 x 5 factorial design, with five N levels (0, 125, 250, 375 and 500 mg pot-1) and five P (P2O5) levels (0, 125, 250, 375 and 500 mg pot-1). Results evidenced that N and P uptake efficiency was influenced by the N and P levels used in the experiment, showing interaction among the studied factors. N translocation efficiency was considerably lower than that of P, probably due to the lower concentration of nitrogenous compounds in the roots than in the shoot. P use efficiency was higher due to the lower concentration of this element in the plant. N and P uptake was influenced by the level of these elements in the soil, being possible to estimate the levels of these nutrients which provide higher uptake, translocation and use efficiency besides total content.


Assuntos
Fósforo/administração & dosagem , Absorção , Panax/classificação , Nitrogênio/administração & dosagem
3.
Rev. bras. plantas med ; 13(3): 265-270, 2011. graf, tab
Artigo em Português | LILACS | ID: lil-601031

RESUMO

Com objetivo de avaliar a produção de biomassa e absorção de N e P pela Pfaffia glomerata em função de doses de N e P, foi realizado o presente trabalho, em casa de vegetação, utilizando como substrato Latossolo Vermelho distroférrico, coletado na camada de 0 - 20 cm. O delineamento foi inteiramente casualizado com três repetições e os tratamentos foram dispostos em esquema fatorial 5 x 5, sendo cinco doses de N (0, 125, 250, 375 e 500 mg vaso-1) e cinco doses de P (0, 125, 250, 375 e 500 mg vaso-1). As variáveis analisadas foram altura de plantas, massa fresca e seca da parte aérea e radicular e teores de N e P na parte aérea e radicular. Os resultados evidenciaram efeito interativo do N e P, em todas as variáveis analisadas, exceto com relação ao teor de P na parte aérea e radicular. A produção de biomassa e absorção de N e P pela Pfaffia glomerata foi influenciada pelas doses de N e P utilizadas no experimento e para a produtividade ótima das características avaliadas, as doses de N variaram entre 42,9 e 346,01 mg vaso-1 e as doses de P entre os valores de 72,02 e 500 mg vaso-1.


With the aim of evaluating biomass production and N and P uptake by Pfaffia glomerata according to N and P levels, the present study was carried out in a greenhouse, using as substrate Oxisol collected at the layer 0 - 20 cm. Experimental design was completely randomized, with three replicates and treatments arranged in 5 x 5 factorial arrangement, with five N levels (0, 125, 250, 375 and 500 mg pot-1) and five P levels (0, 125, 250, 375 and 500 mg pot-1). The assessed parameters were plant height, shoot and root fresh and dry matter, and N and P levels in shoot and roots. Results evidenced an interactive effect of N and P for all studied variables, except for N and P levels in shoot and roots. Biomass production and N and P uptake by Pfaffia glomerata were influenced by the N and P levels used in the experiment, whereas the optimal productivity was obtained with N levels ranging between 42.9 and 346.01 mg pot-1 and P levels between 72.02 and 500 mg pot-1.


Assuntos
Absorção , Amaranthaceae/crescimento & desenvolvimento , Biomassa , Compostos de Fósforo/análise , Compostos de Nitrogênio/análise , Monitoramento Ambiental , Plantas Medicinais , Esterco/análise , Brasil , Substratos para Tratamento Biológico/análise
4.
Rev. bras. plantas med ; 13(3): 276-281, 2011. tab
Artigo em Português | LILACS | ID: lil-601033

RESUMO

Apesar de vários usos na cultura popular, poucos trabalhos vêm sendo desenvolvidos em relação ao cultivo do manjericão, sendo a maior parte dos estudos relacionada à identificação dos compostos químicos e à farmacologia. Este trabalho foi realizado com o objetivo de avaliar o efeito de diferentes luminosidades e substratos na emergência, crescimento inicial e qualidade de mudas de manjericão. Utilizaram-se três substratos (substrato comercial Plantmax®, mistura de terra + areia + cama de frango (1:1:1) e terra + areia + Plantmax® (1:1:1) e dois níveis de luminosidade (Pleno Sol e 50 por cento). O delineamento experimental foi de blocos casualizados em esquema fatorial 2 (Luz) x 3 (Substratos), com quatro repetições. Avaliou-se diariamente o percentual e o índice de velocidade de emergência, e aos 60 dias após a semeadura, o crescimento e a qualidade da muda. Os substratos e níveis de luz não alteraram a porcentagem de emergência das plântulas, entretanto a velocidade de emergência foi maior em Plantmax quando em pleno sol e não diferiu entre os substratos em 50 por cento de sombreamento. No substrato terra + areia + cama-de-frango e a pleno sol as mudas apresentaram maior crescimento e qualidade. Recomenda-se a semeadura direta do manjericão em terra + areia + cama de frango pois evita-se o transplante minimizando as perdas e a necessidade de mão de obra.


Although sweet basil has been frequently used in popular culture, few studies have been developed concerning its cultivation, and most of them are related to the identification of its chemical compounds and pharmacology. The aim of this study was to assess the effect of different luminosities and substrates on the emergence, initial growth and quality of sweet basil seedlings. Three substrates (Plantmax® commercial substrate, a mixture of soil + sand + chicken manure (1:1:1), and soil + sand + Plantmax® (1:1:1) were used, together with two light levels (Full sun and 50 percent). The experimental design was in randomized blocks, in 2 (Light) x 3 (Substrates) factorial arrangement with four replicates. The emergence percentage and velocity index were daily evaluated, and at 60 days after sowing seedling growth and quality were also evaluated. The substrates and light levels did not alter the percentage of seedling emergence; however, the emergence velocity was higher in Plantmax and full sun but did not differ among substrates under 50 percent shading. In the substrate soil + sand + chicken manure and full sun, seedlings had higher growth and quality. It is recommended thus that sweet basil be directly sown in soil + sand + chicken manure since it prevents transplanting, minimizing losses and the need of labor.


Assuntos
Brotos de Planta/crescimento & desenvolvimento , Eficiência/fisiologia , Ocimum basilicum/anatomia & histologia , Ocimum basilicum/crescimento & desenvolvimento , Estimulação Luminosa , Substratos para Tratamento Biológico/análise , Análise de Variância , Brasil , Terapêutica/estatística & dados numéricos
5.
J Shoulder Elbow Surg ; 5(6): 471-6, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8981273

RESUMO

This study evaluates disuse osteoporosis of the proximal humerus after shoulder surgery and immobilization. This was accomplished by quantifying bone mineral density changes in 22 patients' proximal humeri after 6 weeks of immobilization for soft-tissue shoulder surgery. The bone mineral density of the humeral head, neck, and proximal diaphyseal subregions was determined 1 to 2 weeks before surgery and at 3, 6, and 12 weeks after surgery with dual-energy x-ray absorptiometry. By the sixth postoperative week statistically significant bone mineral density decreases of 6% to 14% were observed in the humeral neck and head subregions, respectively. The changes in these three regions diminished slightly after 6 weeks of remobilization, but the differences were still statistically significant. No significant bone mineral density changes occurred in any subregion or during any time interval in the nonoperated humerus. Our study represents the first report with dual-energy x-ray absorptiometry to quantify bone loss of the proximal humerus of patients after shoulder immobilization. Further long-term study is warranted to determine the clinical significance of this bone loss and to determine whether these losses are partially or fully recoverable.


Assuntos
Densidade Óssea , Úmero/fisiologia , Imobilização , Ombro/cirurgia , Absorciometria de Fóton , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório
6.
J Bone Miner Res ; 11(7): 1033-9, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8797126

RESUMO

Cross-sectional studies have demonstrated significant decreases in bone mass in femoral cortical bone adjacent to prostheses. Thirty-six patients who had undergone 31 cemented and 9 uncemented primary total hip arthroplasties (THA) were prospectively studied to define further the natural history of this femoral cortical bone loss. Dual-energy X-ray absorptiometry (DXA) was employed to quantify bone mineral density (BMD) changes in four subregions around the femoral prostheses. Femoral BMD loss (average 12.3%) was observed in the three proximal subregions 2 months postoperatively. This loss increased to 21.2% by 6 months postoperatively, and by 2 years postoperatively it averaged 25.5% in the same three subregions. There were no significant BMD changes in the subregion distal to the prosthesis tip or in the contralateral hip. Subgroups were compared based on prosthesis size and cement use. Statistically significant differences in BMD loss were observed between the large cemented cobalt chrome prosthesis group (n = 8) and the large uncemented titanium prosthesis group (n = 8). These differences were only present in the most proximal medial subregion where the large cemented groups had twice the bone loss in this area as compared with the large uncemented group. The data indicate that bone loss occurs adjacent to femoral prosthesis within 2 months of surgery and that DXA is a useful technique to quantify prospectively femoral cortical bone loss following THA.


Assuntos
Cimentos Ósseos/efeitos adversos , Cabeça do Fêmur/patologia , Prótese de Quadril/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Estudos Transversais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
7.
J Orthop Trauma ; 10(7): 455-61, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8892144

RESUMO

The purpose of this study was to review our intermediate-term experience with posterior fracture-dislocations of the hip. We evaluated the accuracy of the Pipkin and Brumback classification schemes as predictors of outcome, assessed the importance of certain treatment variables, and determined the complication rates of this injury in a group of 33 patients followed for an average of 49 months. The overall results were 67% good, 18% fair, and 15% poor, with no excellent results. The Pipkin classification scheme was a useful predictor of outcome because patients with less severe Pipkin 1 or 2 injuries had statistically significant better outcomes than did those who sustained Pipkin 3 or 4 injuries (p < 0.02). Due to a large number of subgroups, we could not demonstrate the usefulness of the Brumback classification system as a predictor of outcome. There were no statistically significant differences in outcome or complication rates when comparing time with hip reduction, definitive operative intervention, or anatomic operative approach to injury. Our study represents the second largest report on posterior dislocation of the hip associated with femoral head fracture. Although outcome of the patients in our series is not outstanding, the 67% good results represent a significant improvement over all previous reports with large numbers of patients. We demonstrate significant improvement in prognosis when treatment goals for these injuries include anatomic reduction, restoration of hip joint stability, and removal of all interposed bone fragments.


Assuntos
Luxação do Quadril/classificação , Fraturas do Quadril/classificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite/etiologia , Feminino , Fixação Interna de Fraturas/métodos , Luxação do Quadril/cirurgia , Fraturas do Quadril/complicações , Fraturas do Quadril/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Ossificação Heterotópica/etiologia , Paralisia/etiologia , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Nervo Isquiático/lesões , Fatores de Tempo , Resultado do Tratamento
8.
J Virol ; 63(5): 2036-47, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2539500

RESUMO

In herpes simplex virus type 2, the mRNAs of ICP4 and ICP22/47 are divergently transcribed and their transcription initiation sites are separated by 750 base pairs (L. J. Whitton and J. B. Clements, Nucleic Acids Res. 12:2061-2078, 1984). This 750-base-pair region contains many recognized cis-acting elements, including two TATA boxes, numerous Sp1-binding sites, four TAATGARAT motifs, at least one ICP4-binding site, and two origins of replication (oriS) linked in tandem. In this report, we describe the construction of mutant viruses with defined deletions that eliminate these elements either singly or in combination. The phenotypic properties of these mutants indicate that (i) the TAATGARAT motifs and their neighboring elements affect the levels of transcription of both ICP4 and ICP22/47 similarly, (ii) the TATA box serving ICP4 is required for efficient ICP4 mRNA synthesis and for determining the initiation site of transcription, (iii) the ICP4-binding site located at the start of ICP4 transcription is at least partially responsible for the decreased levels of ICP4 mRNA observed in the presence of immediate-early and early gene products, and (iv) mutants bearing deletions that eliminate the entire conventionally recognized ICP4 promoter generate sufficient ICP4 mRNA to maintain viability in cells not expressing ICP4. Additionally, our inability to generate viable deletion mutants lacking all copies of oriS suggests that at least one copy of oriS may be essential for virus replication.


Assuntos
DNA Viral/genética , Genes Virais , Regiões Promotoras Genéticas , Sequências Reguladoras de Ácido Nucleico , Simplexvirus/genética , Proteínas Virais/genética , Replicação Viral , Deleção Cromossômica , Análise Mutacional de DNA , Regulação da Expressão Gênica , RNA Mensageiro/genética , RNA Viral/genética , Mapeamento por Restrição , Simplexvirus/crescimento & desenvolvimento
9.
J Virol ; 62(3): 715-21, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2828666

RESUMO

ts701 is a temperature-sensitive mutant of herpes simplex virus type 1 strain KOS induced by hydroxylamine mutagenesis (C.T. Chu, D. S. Parris, R. A. F. Dixon, F. E. Farber, and P. A. Schaffer, Virology 98:168-181, 1979). In the present study, the mutation rendering ts701 temperature sensitive was mapped to coordinates 0.609 through 0.614 in the UL region of the genome. At the nonpermissive temperature, ts701 (i) failed to induce the synthesis of viral DNA, (ii) exhibited a dramatically reduced ability to drive replication of a plasmid containing the herpes simplex virus origin of viral DNA synthesis, oriS, (iii) generated no viral polypeptides of the late (gamma 2) kinetic class, and (iv) produced virions with electron-translucent cores. Northern (RNA) blot hybridization demonstrated that two mRNAs--one of the beta kinetic class and one of the gamma kinetic class--hybridized to a 1.3-kilobase viral DNA fragment that rescued the mutation in ts701. Based on the phenotype and mapping of ts701, it is likely that its mutation lies in the gene specifying the 65,000-Mr DNA-binding protein (65KDBP) recently described by Marsden et al. (H.S. Marsden, M.E.M. Campbell, L. Haarr, M. C. Frame, D. S. Parris, M. Murphy, R. G. Hope, M. T. Muller, and C. M. Preston, J. Virol. 61:2428-2437, 1987).


Assuntos
Replicação do DNA , Genes Virais , Simplexvirus/genética , Replicação Viral , DNA Viral/biossíntese , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/fisiologia , Mutação , RNA Mensageiro/análise , RNA Viral/análise , Temperatura , Proteínas Virais/genética , Proteínas Virais/fisiologia
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