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1.
Pulmonology ; 29(4): 276-283, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-33272909

RESUMO

INTRODUCTION: Several multidimensional indices have been proposed to predict mortality in chronic obstructive pulmonary disease (COPD). The BODEX index is simple and easy to use for this purpose in all clinical settings. Only a few prognostic indices have integrated oxygenation variables, with measurement methods that are not practical for real life clinical practice in all settings. OBJECTIVES: To develop and externally validate a new prognostic index (BODEXS90) that combines the variables included in BODEX index with rest peripheral oxygen saturation measured with finger oximetry (SpO2) to predict all-cause mortality in stable COPD. METHOD: Observational, non-intervention, multicenter historic cohort study. The BODEXS90 index was developed in a derivation cohort and externally validated in a validation cohort. Calibration of the index was carried out using Hosmer-Lemeshow test. The discrimination capacity of BODEXS90 and BODEX were compared by means of receiver-operating characteristics curves. Modelling of the index was carried out by crude and adjusted Cox regression analysis. RESULTS: The derivation and validation cohorts included 787 and 1179 subjects, respectively. SpO2 predicted all cause-mortality independently of BODEX index. Discrimination capacity of BODEXS90 to predict the outcome was significantly higher than that of BODEX, particularly for more severely affected patients, both in the derivation and in the validation cohorts. CONCLUSIONS: The new index is potentially useful for designing clinical decision-making algorithms in stable COPD.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Humanos , Prognóstico , Estudos de Coortes , Pulmão , Oximetria
2.
Int J Oral Maxillofac Surg ; 48(5): 601-611, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30598335

RESUMO

The aim of this systematic review was to describe the anatomical and surgical factors related to cranial nerve injuries in Le Fort I osteotomy. The protocol of this systematic review was registered in the International Prospective Register of Systematic Reviews (PROSPERO). Two independent reviewers performed an unrestricted electronic database search in the MEDLINE/PubMed, LILACS, Scopus, Web of Science, and Cochrane databases up to and including August 2018. Thirty-two articles were selected for data extraction and synthesis: 30 studies were identified in the main search and two by a manual search. The level of agreement between the reviewers was considered excellent (κ=0.779 for study selection and κ=0.767 for study eligibility). This study revealed that the main nerve affected was the trigeminal nerve, followed by the oculomotor, abducens, optic, facial, and vagus and accessory nerves. Cleft lip and palate patients presented the highest incidence of cranial nerve damage. Cranial nerve damage after Le Fort I osteotomy is not rare. Anatomical and structural knowledge of the patient are necessary in order to minimize the risks of cranial nerve injury in Le Fort I osteotomy.


Assuntos
Fenda Labial , Traumatismos dos Nervos Cranianos , Humanos , Maxila , Osteotomia Maxilar , Osteotomia de Le Fort , Estudos Prospectivos
3.
Rev. bras. plantas med ; 18(2): 415-422, 2016. tab
Artigo em Português | LILACS | ID: lil-787949

RESUMO

RESUMO O objetivo deste estudo foi avaliar o efeito antibacteriano e tripanocida in vitro do extrato hidroalcóolico das raízes de Tradescantia sillamontana Matuda (Commelinaceae), conhecida popularmente como veludo branco. Foi avaliada a atividade antibacteriana in vitro frente às bactérias Streptococcus mitis (CIM = 100 µg/mL; CMB = 150 µg/mL), Streptococcus mutans (CIM = 200 µg/mL; CMB = 220 µg/mL), Streptococcus sanguinis (CIM = 400 µg/mL; CMB = 425 µg/mL), Streptococcus sobrinus (CIM = 400 µg/mL; CMB = 420 µg/mL) e Bacteroides fragilis (CIM = 400 µg/mL; CMB = 430 µg/mL) pelo método de diluição em caldo. Os protozoários da família tripanossomatídeo causam doenças tropicais que costumam ser negligenciadas que costumam ser como a tripanossomíase, para a qual estão disponíveis poucos medicamentos. Neste contexto, o extrato hidroalcóolico das raízes de T. sillamontana também foi avaliado frente às formas tripomastigotas da cepa Y de Trypanosoma cruzi, com promissora atividade frente a este protozoário (IC50 = 2,4 µg/mL). Quando avaliada a atividade citotóxica frente a fibroblastos da linhagem LLCMK2, o extrato apresentou moderada citotoxicidade (CC50 = 480,37 µg/mL). Os resultados ora apresentados para o extrato hidroalcóolico das raízes de Tradescantia sillamontana Matuda demonstraram promissoras atividades antibacteriana e tripanocida, sendo uma fonte alternativa de produtos naturais com atividades contra T. cruzi e algumas bactérias do gênero Streptococcus e Bacteroides.


ABSTRACT The aim of this study was to investigate the in vitro, antibacterial and trypanocidal effect of the hydroalcoholic extract from the roots of Tradescantia sillamontana Matuda (Commelinaceae), commonly known as Veludo branco. The in vitro antibacterial activity against the standard bacteria Streptococcus mitis (MIC = 100µg/mL; MBC = 150 µg/mL), Streptococcus mutans (MIC = 200µg/mL; MBC = 220 µg/mL), Streptococcus sanguinis (MIC = 400µg/mL; MBC = 425 µg/mL), Streptococcus sobrinus (MIC = 400µg/mL; MBC = 420 µg/mL) andBacteroides fragilis (MIC = 400µg/mL; MBC = 430 µg/mL), using microdilution broth methods. Protozoans from the trypanosomatid family cause neglected tropical diseases such as trypanosomiasis, for which few drugs are available. In this context, the hydroalcoholic extract of the Tradescantia sillamontana roots was also investigated with regards to the in vitro effects against the trypomastigote forms of theY strain of Trypanosoma cruzi, showing strong activity against this parasite (IC50 = 2.4 µg/mL). When performing cytotoxic activity against fibroblasts LLCMK2 line, the extract showed moderate cytotoxicity (CC50 = 480.37 mg/mL). The results presented for the hydroalcoholic extract of the roots of Tradescantia sillamontana Matuda demonstrated effective antibacterial and trypanocidal activities and were shown to be an alternative source of natural products with activity against T. cruzi and some bacteria of the genus Streptococcus and Bacteroides.


Assuntos
Tripanossomicidas/análise , Raízes de Plantas/classificação , Tradescantia/classificação , /análise , Antibacterianos/análise , Commelinaceae/classificação
4.
Rev. bras. plantas med ; 18(2): 502-510, 2016. tab, graf
Artigo em Português | LILACS | ID: lil-787951

RESUMO

RESUMO Campomanesia adamantium é muito utilizada na medicina popular no tratamento de hipertensão, reumatismo e diabetes. Objetivou-se com o presente trabalho avaliar o rendimento, a composição química, e as atividades antimicrobiana e antioxidante do óleo essencial de folhas de C. adamantium submetidas a diferentes métodos e tempos de secagem. O delineamento utilizado foi inteiramente casualizado, com oito tratamentos e três repetições. O óleo essencial foi extraído por hidrodestilação das folhas e analisado por CG-EM. O tipo de secagem das folhas de C. adamantium influenciou no teor e na composição química do óleo essencial. Os constituintes espatulenol, óxido cariofileno e germacreno-B apresentaram maior concentração na maioria das procedências avaliadas. O óleo essencial das folhas de C. adamantium apresentou moderada atividade antibacteriana em relação a todos os micro-organismos testados. A atividade antioxidante se deu empregando-se o método de redução do radical estável DPPH, sendo observada fraca atividade antioxidante por meio do ensaio utilizado.


ABSTRACT C. adamantiumis widely used in popular medicine for thetreatment of hypertension, rheumatism and diabetes. This study looked to evaluate the essential oil yield, the chemical composition and the antimicrobial and antioxidant activities of the essential oil from leaves of C. adamantium. A completely randomized design was used with eight treatments and three replications. The essential oil obtained by hydrodestillation of the leaves was analyzed by GC-MS. The results show that the drying type and the processing of the leaf influence the content and chemical composition of the essential oil. The compounds spathulenol, caryophyllene oxide and germacrene-B have higher concentrationsin mostorigins. The essentialoil from theleaves of C.adamantiumshowed moderate bacterial activityagainst all tested microorganisms. The antioxidant activity was determined by the methods of reduction of the DPPH stable radical. The antioxidant activity was weak in the test used.


Assuntos
Óleos Voláteis/análise , Myrtaceae/química , Anti-Infecciosos/análise , Antioxidantes/análise , Sesquiterpenos/farmacologia
5.
Phytomedicine ; 21(11): 1298-302, 2014 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-25172793

RESUMO

OBJECTIVE: The essential oil from the leaves of Ocimum kilimandscharicum (EOOK), collected in Dourados-MS, was investigated for anticancer, anti-inflammatory and antioxidant activity and chemical composition. MATERIALS AND METHODS: The essential oil was extracted by hydrodistillation, and the chemical composition was performed by gas chromatography-mass spectrometry. The essential oil was evaluated for free radical-scavenging activity using the DPPH assay and was tested in an anticancer assay against ten human cancer cell lines. The response parameter (GI50) was calculated for the cell lines tested. The anti-inflammatory activity was evaluated using carrageenan-induced pleurisy in mice. RESULTS: The chemical composition showed 45 components with a predominance of monoterpenes, such as camphor (51.81%), 1,8 cineole (20.13%) and limonene (11.23%). The EOOK exhibited potent free radical-scavenging activity by the DPPH assay with a GI50 of 8.31 µg/ml. The major constituents, pure camphor (IC50=12.56 µg/ml) and mixture of the limonene: 1, 8 cineole (IC50=23.25 µg/ml) displayed a potent activity. The oral administration of EOOK (at 30 and 100 mg kg(-1)), as well as the pure camphor or a mixture of 1,8 cineole with limonene, significantly inhibited the carrageenan (Cg) induced pleurisy, reducing the migration of total leukocytes in mice by 82 ± 4% (30 mg kg(-1) of EOOK), 95 ± 4% (100 mg kg(-1) of EOOK), 83 ± 9% (camphor) and 80 ± 5% (mixture of 1,8 cineole:limonene 1:1). In vitro cytotoxicity screening against a human ovarian cancer cell line displayed high selectivity and potent anticancer activity with GI50=31.90 mg ml(-1). This work describes the anti-inflammatory, anticancer and antioxidant effects of EOOK for the first time. CONCLUSIONS: The essential oil exhibited marked anti-inflammatory, antioxidant and anticancer effects, an effect that can be attributed the presence of majorital compounds, and the response profiles from chemical composition differed from other oils collected in different locales.


Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Sequestradores de Radicais Livres/farmacologia , Ocimum/química , Óleos Voláteis/farmacologia , Animais , Cânfora/química , Cânfora/farmacologia , Linhagem Celular Tumoral , Cicloexanóis/química , Cicloexanóis/farmacologia , Cicloexenos/química , Cicloexenos/farmacologia , Eucaliptol , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Limoneno , Camundongos , Monoterpenos/química , Monoterpenos/farmacologia , Óleos Voláteis/química , Folhas de Planta/química , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Terpenos/química , Terpenos/farmacologia
6.
Int J Cosmet Sci ; 31(6): 445-50, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19467029

RESUMO

A rapid HPLC method was developed for the assay of tocopheryl acetate and ascorbyl tetraisopalmitate in cosmetic formulations. The validated method was applied for quantitative determination of these vitamins in simulated emulsion formulation. Samples were analysed directly on a RP-18 reverse phase column with UV detection at 222 nm. A mixture of methanol and isopropanol (25 : 75 v/v) was used as mobile phase. The retention time of tocopheryl acetate and ascorbyl tetraisopalmitate were 3.0 min and 5.9 min, respectively. Recovery was between 95% and 104%. In addition, the excipients did not interfere in the analysis. The method is simple, reproducible, selective and is suitable for routine analyses of commercial products.


Assuntos
Antioxidantes/análise , Ácido Ascórbico/análogos & derivados , Cosméticos/química , Tocoferóis/análise , Ácido Ascórbico/análise , Cromatografia Líquida de Alta Pressão/métodos
7.
Braz J Med Biol Res ; 38(11): 1593-601, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16258627

RESUMO

Serine-proteases are involved in vital processes in virtually all species. They are important targets for researchers studying the relationships between protein structure and activity, for the rational design of new pharmaceuticals. Trypsin was used as a model to assess a possible differential contribution of hydration water to the binding of two synthetic inhibitors. Thermodynamic parameters for the association of bovine beta-trypsin (homogeneous material, observed 23,294.4 +/- 0.2 Da, theoretical 23,292.5 Da) with the inhibitors benzamidine and berenil at pH 8.0, 25 degrees C and with 25 mM CaCl2, were determined using isothermal titration calorimetry and the osmotic stress method. The association constant for berenil was about 12 times higher compared to the one for benzamidine (binding constants are K = 596,599 +/- 25,057 and 49,513 +/- 2,732 M(-1), respectively; the number of binding sites is the same for both ligands, N = 0.99 +/- 0.05). Apparently the driving force responsible for this large difference of affinity is not due to hydrophobic interactions because the variation in heat capacity (DeltaCp), a characteristic signature of these interactions, was similar in both systems tested (-464.7 +/- 23.9 and -477.1 +/- 86.8 J K(-1) mol(-1) for berenil and benzamidine, respectively). The results also indicated that the enzyme has a net gain of about 21 water molecules regardless of the inhibitor tested. It was shown that the difference in affinity could be due to a larger number of interactions between berenil and the enzyme based on computational modeling. The data support the view that pharmaceuticals derived from benzamidine that enable hydrogen bond formation outside the catalytic binding pocket of beta-trypsin may result in more effective inhibitors.


Assuntos
Benzamidinas/química , Diminazena/análogos & derivados , Inibidores da Tripsina/química , Tripsina/química , Animais , Calorimetria , Bovinos , Diminazena/química , Concentração de Íons de Hidrogênio , Modelos Químicos , Estrutura Molecular , Pressão Osmótica , Ligação Proteica , Prótons , Termodinâmica , Água/química
8.
Braz. j. med. biol. res ; 38(11): 1593-1601, Nov. 2005.
Artigo em Inglês | LILACS | ID: lil-414713

RESUMO

Serine-proteases are involved in vital processes in virtually all species. They are important targets for researchers studying the relationships between protein structure and activity, for the rational design of new pharmaceuticals. Trypsin was used as a model to assess a possible differential contribution of hydration water to the binding of two synthetic inhibitors. Thermodynamic parameters for the association of bovine ß-trypsin (homogeneous material, observed 23,294.4 ± 0.2 Da, theoretical 23,292.5 Da) with the inhibitors benzamidine and berenil at pH 8.0, 25°C and with 25 mM CaCl2, were determined using isothermal titration calorimetry and the osmotic stress method. The association constant for berenil was about 12 times higher compared to the one for benzamidine (binding constants are K = 596,599 ± 25,057 and 49,513 ± 2,732 M-1, respectively; the number of binding sites is the same for both ligands, N = 0.99 ± 0.05). Apparently the driving force responsible for this large difference of affinity is not due to hydrophobic interactions because the variation in heat capacity (DCp), a characteristic signature of these interactions, was similar in both systems tested (-464.7 ± 23.9 and -477.1 ± 86.8 J K-1 mol-1 for berenil and benzamidine, respectively). The results also indicated that the enzyme has a net gain of about 21 water molecules regardless of the inhibitor tested. It was shown that the difference in affinity could be due to a larger number of interactions between berenil and the enzyme based on computational modeling. The data support the view that pharmaceuticals derived from benzamidine that enable hydrogen bond formation outside the catalytic binding pocket of ß-trypsin may result in more effective inhibitors.


Assuntos
Animais , Bovinos , Benzamidinas/química , Diminazena/análogos & derivados , Inibidores da Tripsina/química , Tripsina/química , Água/química , Calorimetria , Diminazena/química , Concentração de Íons de Hidrogênio , Modelos Químicos , Estrutura Molecular , Pressão Osmótica , Ligação Proteica , Prótons , Termodinâmica
9.
In. III Congresso Latino Americano de Engenharia Biomédica - CLAEB / International Federation for Medical and Biological Engineering - IFMBE Proceedings. Anais. João Pessoa, SBEB, 2004. p.1343-1346, 1 CD-ROM - III Congresso Latino Americano de Engenharia Biomédica - CLAEB / International Federation for Medical and Biological Engineering - IFMBE Proceedings, tab, ilus.
Monografia em Português | LILACS | ID: lil-540464

RESUMO

The aim of this work is to analize the evolution of osteotomies in goat's tibia by image processing...


Assuntos
Regeneração Óssea , Calo Ósseo , Processamento de Imagem Assistida por Computador , Ovinos , Tíbia , Fraturas da Tíbia
10.
Braz J Med Biol Res ; 33(1): 19-26, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10625870

RESUMO

The genus Acanthamoeba comprises free-living amebae identified as opportunistic pathogens of humans and other animal species. Morphological, biochemical and molecular approaches have shown wide genetic diversity within the genus. In an attempt to determine the genetic relatedness among isolates of Acanthamoeba we analyzed randomly amplified polymorphic DNA (RAPD) profiles of 11 Brazilian isolates from cases of human keratitis and 8 American type culture collection (ATCC) reference strains. We found that ATCC strains belonging to the same species present polymorphic RAPD profiles whereas strains of different species show very similar profiles. Although most Brazilian isolates could not be assigned with certainty to any of the reference species, they could be clustered according to pattern similarities. The results show that RAPD analysis is a useful tool for the rapid characterization of new isolates and the assessment of genetic relatedness of Acanthamoeba spp. A comparison between RAPD analyses and morphological characteristics of cyst stages is also discussed.


Assuntos
Ceratite por Acanthamoeba/parasitologia , Acanthamoeba/genética , DNA de Protozoário/análise , Técnica de Amplificação ao Acaso de DNA Polimórfico , Acanthamoeba/classificação , Acanthamoeba/crescimento & desenvolvimento , Animais , Primers do DNA/análise , Variação Genética , Humanos , Estágios do Ciclo de Vida/genética
11.
Braz. j. med. biol. res ; 33(1): 19-26, Jan. 2000. tab, ilus
Artigo em Inglês | LILACS | ID: lil-252252

RESUMO

The genus Acanthamoeba comprises free-living amebae identified as opportunistic pathogens of humans and other animal species. Morphological, biochemical and molecular approaches have shown wide genetic diversity within the genus. In an attempt to determine the genetic relatedness among isolates of Acanthamoeba we analyzed randomly amplified polymorphic DNA (RAPD) profiles of 11 Brazilian isolates from cases of human keratitis and 8 American type culture collection (ATCC) reference strains. We found that ATCC strains belonging to the same species present polymorphic RAPD profiles whereas strains of different species show very similar profiles. Although most Brazilian isolates could not be assigned with certainty to any of the reference species, they could be clustered according to pattern similarities. The results show that RAPD analysis is a useful tool for the rapid characterization of new isolates and the assessment of genetic relatedness of Acanthamoeba spp. A comparison between RAPD analyses and morphological characteristics of cyst stages is also discussed (au)


Assuntos
Animais , Humanos , Ceratite por Acanthamoeba/parasitologia , Acanthamoeba/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Acanthamoeba/crescimento & desenvolvimento , Acanthamoeba/isolamento & purificação , Primers do DNA/análise , Variação Genética , Estágios do Ciclo de Vida/genética
12.
Calcif Tissue Int ; 58(5): 362-7, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8661972

RESUMO

Measurements of ultrasonic velocity and specific differential attenuation (SDA) were obtained on 24 bovine trabecular bone specimens from the femoral condyles. The measurements were obtained using two pairs of ultrasonic transducers, one with a low nominal center frequency (500 kHz) and the other pair with a high nominal center frequency (1 MHz). The ultrasonic velocity and specific differential attenuation associated with the bone samples were determined both with and without marrow, i.e., replacing the marrow with water in the pores of the trabecular bone. Significant increases (2.1% and 2.9%) in the velocity of ultrasound were observed after removal of the marrow, for the low and high frequency transducer pairs, respectively. In contrast, significant decreases (-6.5% and -8.8%) in SDA were observed after removal of the marrow, for the low and high frequency transducer pairs, respectively. The bone densities (BD) of the samples were also determined using single photon absorptiometry (SPA). Correlations between ultrasonic parameters and bone densities for samples both with and without marrow were found to be similar. For example, for the 1 MHz transducer pair, the correlation between BD and velocity was r = 0. 86 with marrow, and r = 0.89 without marrow. This study also compared the results obtained using a contact (no water bath) technique and an insertion (with a water bath) technique of ultrasonic measurements. For the high frequency transducer pair, the correlation coefficients between the two methods were r = 0.99 and r = 0.93, for the velocity and specific differential attenuation, respectively. Similar results were found for the low frequency transducer pair as well. In addition, approximately equal correlations between BD and ultrasonic velocity and SDA were also found, indicating that contact and insertion measurements provide essentially equivalent information.


Assuntos
Medula Óssea/diagnóstico por imagem , Osso e Ossos/diagnóstico por imagem , Absorciometria de Fóton , Animais , Densidade Óssea , Bovinos , Fêmur , Técnicas In Vitro , Reprodutibilidade dos Testes , Ultrassonografia/métodos
13.
IEEE Trans Biomed Eng ; 43(3): 249-58, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8682537

RESUMO

A comparison study is reported on the ultrasonic assessment of human trabecular and bovine trabecular bone samples. Both ultrasonic velocity and ultrasonic attenuation were evaluated through a transmission insertion technique and correlated with bone mineral density as determined with single photon absorptiometry. For a 1-MHz ultrasonic transducer pair and the human cancellous bone samples the correlations were 0.91 and 0.89 between density and velocity and attenuation, respectively. For a 500-kHz ultrasonic transducer pair the correlations were 0.89 and 0.81 between density and velocity and attenuation, respectively. For the bovine bone samples, the correlations were 0.90 and -0.31 for the velocity and attenuation, respectively, for the 1 MHz transducer pair. For the 500-kHz transducers, the correlations were 0.85 and -0.17 for the velocity and attenuation, respectively. By combining both velocity and attenuation in a multivariate regression, an improvement was achieved in the estimation of bone density in the human samples for both the 500-kHz and 1-MHz transducer pairs. No significant improvement was achieved in the multivariate regressions for the bovine bone samples. In conclusion, the results indicate that ultrasonic measurements are in general highly correlated with bone mineral density in trabecular bone samples. This correlation is more consistent and strong in relatively low density human samples compared with the higher density bovine samples.


Assuntos
Osso e Ossos/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Densidade Óssea , Cadáver , Bovinos , Fêmur/diagnóstico por imagem , Análise de Fourier , Humanos , Análise dos Mínimos Quadrados , Modelos Lineares , Vértebras Lombares/diagnóstico por imagem , Pessoa de Meia-Idade , Transdutores , Ultrassonografia/instrumentação , Ultrassonografia/métodos , Ultrassonografia/estatística & dados numéricos
14.
In. Schiabel, Homero; Slaets, Annie France Frère; Costa, Luciano da Fontoura; Baffa Filho, Oswaldo; Marques, Paulo Mazzoncini de Azevedo. Anais do III Fórum Nacional de Ciência e Tecnologia em Saúde. Säo Carlos, s.n, 1996. p.349-350, graf.
Monografia em Português | LILACS | ID: lil-236388

RESUMO

A atenuação (BUA), medida pela técnica ultra-sônica de caracterização de tecido ósseo, pode ser substituída pela frequência instantânea média (MIF), que é um parâmetro mais simples de ser medido e sem perda de informação, utilizando-se a técnica de inserção por contato no calcanhar do paciente. Uma nova forma de classificação da osteoporose poderá ser criada baseada neste novo parâmetro.


An easy to measure ultrasonic feature namely mean instantanaeous frequency (MJF) has been demonstrated to provide about the sarne information as attenuation (BUA) in a new contact clinical ultrasonic system. A new classification of osteoporosis may be achieved using this new parameter.


Assuntos
Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Osteoporose/classificação , Osso e Ossos , Osteoporose , Transdutores , Absorciometria de Fóton , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Plant Cell Rep ; 13(8): 437-41, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-24194021

RESUMO

The potential of somatic embryogenesis was evaluated for 10 cultivars of sweet potato through extensive embryogenic response and isozyme analysis. Embryogenic callus was induced by incubating lateral buds on Murashige and Skoog medium containing 10 µM 2,4-dichlorophenoxyacetic acid for 6-8 weeks. The frequency of embryogenic response was low, and varied with genotypes, ranging from 0 to 17%. Embryo to plantlet formation could be enhanced by the use of the combination of 2,4-dichlorophenoxyacetic acid with kinetin, both used at 0.01 µM. Embryogenic callus with its potential of plantlet formation has constantly been maintained for over two years. However, after several subcultures, 0.5 to 12% of embryogenic callus reverted irreversibly into friable fast-growing non-embryogenic callus whose ability to regenerate shoots was then definitively lost. The isozymes of esterase, peroxidase, glutamate oxaloacetate transaminase and acid phosphatase investigated in this study were found appropriate to distinguish compact embryogenic from friable non-embryogenic callus in sweet potato. In fact, the callus reversion was associated with a loss of bands or a decline in isozyme activity. On the contrary, very small changes in isozyme activity or no specific changes at all were observed during the differentiation of embryogenic callus into globular embryos.

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