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1.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32008982

RESUMO

INTRODUCTION: The incidence of periprosthetic fractures of the knee is increasing due to the increase in the number of total knee arthroplasties performed, together with population aging. We found few studies that analyze mortality in our setting after surgery. Our objective was to evaluate mortality and survival after surgical treatment of periprosthetic fractures of the distal femur in our environment. MATERIAL AND METHOD: We conducted a retrospective observational study of a consecutive series of 97 patients surgically treated in our centre for periprosthetic knee fracture between 2007-2015, with a minimum follow-up of 12months. Diverse sociodemographic, clinical and surgical variables were analyzed. A consultation was made to the National Death Index of the Ministry of Health for the analysis of mortality and survival was analyzed using the Kaplan-Meier method. RESULTS: We reviewed a total of 97 patients with an average age of 75years, of which 86 were women and 11 were men. Of the patients, 50.5% of patients had some comorbidity. The average delay until the intervention was 3.1days. With respect to the treatment, 45 patients were operated by osteosynthesis with plate (49.5%), 40 with intramedullary nail (41.2%) and 9 with revision of the arthroplasty (9.3%). A total of 30 deaths were recorded during the follow-up, with cumulative mortality in the first year, at 3 and at 10 years of 7.2%, 17.5% and 30.9%, respectively, progressively increasing in people over 75years. There was no significant difference in mortality rates with the osteosynthesis method. The main complication was pseudoarthrosis (6.2%). CONCLUSIONS: Periprosthetic knee fractures are associated with high rates of complications and mortality. The patient's age and the lesion itself are non-modifiable factors that can influence mortality after surgery, while other variables such as the type of intervention or surgical delay did not show differences in mortality rates in our study.


Assuntos
Fraturas do Fêmur/mortalidade , Fraturas do Fêmur/cirurgia , Fixação de Fratura/mortalidade , Fraturas Periprotéticas/mortalidade , Fraturas Periprotéticas/cirurgia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Fixação de Fratura/métodos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos
3.
Lung Cancer ; 135: 230-233, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31235316

RESUMO

OBJECTIVES: To investigate the capacity of a trained dog to identify LC in patients with malignant SPN. METHODS: We collected 90 exhaled gas samples from 30 patients with SPN (3 samples/patient). As controls we used 61 healthy volunteers and 18 COPD patients without SNP or LC, in each of whom we collected 5 exhaled gas samples (n = 395). The dog (Blat, a 4-year-old crossbreed between a Labrador Retriever and a Pitbull) and the methodology used were the same as previously reported by our group (see: https://drive.google.com/open?id=1R4mOtOtuZkTeb5iOEEv0K9r2kHKlPhWd). RESULTS: Of 30 patients with SPN, Blat recognized 27 of them as positive for LC and 3 as negative for LC. These results fully matched post-surgical pathological results. Sensibility was 0.97, Specificity 0.99, Positive Predictive value 0.97 and negative predictive value 0.99. The AUC of the ROC curve was 0.985. CONCLUSIONS: Trained dogs can identify accurately the malignant origin of SPN. It is now time to develop technology that can match canine olfaction and facilitate the implementation of this diagnostic approach in the clinic.


Assuntos
Neoplasias Pulmonares/diagnóstico , Nódulo Pulmonar Solitário/diagnóstico , Idoso , Animais , Estudos de Casos e Controles , Diagnóstico Diferencial , Modelos Animais de Doenças , Cães , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores/métodos , Curva ROC , Reprodutibilidade dos Testes , Nódulo Pulmonar Solitário/patologia
4.
Rev Esp Quimioter ; 30(6): 468-471, 2017 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-29160648

RESUMO

OBJECTIVE: In Spain, the age and sex to which the primary infection by EBV is produced is poorly studied. The objective of this work is to know its relation with the presence of the primary infection by EBV between the years 2006 and 2015 in our health area. METHODS: From the Santiago de Compostela health area between 2006 and 2015, 578 patients with serological patterns of EBV primoinfection were selected. This patients presented serological results of IgM-VCA positive, IgG-VCA positive and EBNA negative. RESULTS: We found 260/578 (45%) adolescents (11- 19 years). In the number of cases by age the maximum was observed, at 2 and 16 years. Between 14-19 years, 62% (79/127) of women between 14-16 years of age, median age 15.8 years (IQ: 14.8-16.4) compared to 48% (49/102) of men, median age 16 years (IQ: 15.7-16.6) (p = 0.032, p = 0.02, respectively). CONCLUSIONS: As in our study, in the developed countries the majority of primary infections by EBV occur in adolescence and a bimodal distribution is observed in relation to age. During adolescence women acquire before men the first infection by EBV.


Assuntos
Infecções por Vírus Epstein-Barr/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina G , Imunoglobulina M , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Espanha/epidemiologia , Adulto Jovem
5.
Rev Esp Enferm Dig ; 102(9): 519-25, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20883067

RESUMO

OBJECTIVE: viral and host factors are related with progression of pathological lesion in chronic hepatitis B. We analyzed these factors in patients with moderate or intermittently elevated ALT levels, and its threshold that determinate significant histological activity. PATIENTS AND METHODS: retrospective analyses of viral and host parameters in 89 consecutive chronic hepatitis B patients biopsied because of moderate or intermittently elevated ALT levels [1-2 x ULN (ULN = 39 IU/ml)] and/or DNA-HBV > 2 x 10³ IU/ml in AntiHBe+ patients. It was analyzed age, gender, ALT levels, HBeAg, viral load and genotype. It was considered advanced histological lesion a Knodell Score (KS) > 7 and histological lesion indicating treatment, lobular inflammation ≥2 or fibrosis ≥2 according to Scheuer Classification. RESULTS: KS > 7 and histological lesion indicating treatment was found in 47.8 and 60.7% respectively. It was observed relationship between age, male gender, ALT levels and viral load with histological damage (p < 0.05). Frequency of advanced lesion indicating treatment was upper in patients with ALT levels > ULN (69.1 vs. 47.1%, p = 0.04). There were not significant upper frequencies of advanced lesion when a cut-off of 40 years or DNA-HBV > 2 x 10³ IU/ml viral load or serological status HBeAg was considerate. Histological activity was lesser in genotype D patients than those infected with others genotypes (p < 0.05). CONCLUSION: upper frequency of advanced histological lesion in chronic hepatitis B patients with moderate or intermittently elevated ALT levels make recommended liver biopsy, independent of viral load and serological status HBeAg. Other factors like age, gender or genotype can help to indicate biopsy in individual cases.


Assuntos
Alanina Transaminase/sangue , Hepatite B Crônica/sangue , Hepatite B Crônica/patologia , Adulto , Feminino , Hepatite B Crônica/virologia , Humanos , Masculino , Estudos Retrospectivos , Índice de Gravidade de Doença
6.
Gastroenterol Hepatol ; 27(2): 51-4, 2004 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-14733879
7.
J Opt Soc Am A Opt Image Sci Vis ; 18(8): 1793-803, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11488483

RESUMO

From both a fundamental and a clinical point of view, it is necessary to know the distribution of the eye's aberrations in the normal population and to be able to describe them as efficiently as possible. We used a modified Hartmann-Shack wave-front sensor to measure the monochromatic wave aberration of both eyes for 109 normal human subjects across a 5.7-mm pupil. We analyzed the distribution of the eye's aberrations in the population and found that most Zernike modes are relatively uncorrelated with each other across the population. A principal components analysis was applied to our wave-aberration measurements with the resulting principal components providing only a slightly more compact description of the population data than Zernike modes. This indicates that Zernike modes are efficient basis functions for describing the eye's wave aberration. Even though there appears to be a random variation in the eye's aberrations from subject to subject, many aberrations in the left eye were found to be significantly correlated with their counterparts in the right eye.


Assuntos
Modelos Biológicos , Fenômenos Fisiológicos Oculares , Erros de Refração/fisiopatologia , Adulto , Humanos , Pessoa de Meia-Idade
8.
J Opt Soc Am A Opt Image Sci Vis ; 18(5): 1003-15, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11336203

RESUMO

An ideal correcting method, such as a customized contact lens, laser refractive surgery, or adaptive optics, that corrects higher-order aberrations as well as defocus and astigmatism could improve vision. The benefit achieved with this ideal method will be limited by decentration. To estimate the significance of this potential limitation we studied the effect on image quality expected when an ideal correcting method translates or rotates with respect to the eye's pupil. Actual wave aberrations were obtained from ten human eyes for a 7.3-mm pupil with a Shack-Hartmann sensor. We computed the residual aberrations that appear as a result of translation or rotation of an otherwise ideal correction. The model is valid for adaptive optics, contact lenses, and phase plates, but it constitutes only a first approximation to the laser refractive surgery case where tissue removal occurs. Calculations suggest that the typical decentrations will reduce only slightly the optical benefits expected from an ideal correcting method. For typical decentrations the ideal correcting method offers a benefit in modulation 2-4 times higher (1.5-2 times in white light) than with a standard correction of defocus and astigmatism. We obtained analytical expressions that show the impact of translation and rotation on individual Zernike terms. These calculations also reveal which aberrations are most beneficial to correct. We provided practical rules to implement a selective correction depending on the amount of decentration. An experimental study was performed with an aberrated artificial eye corrected with an adaptive optics system, validating the theoretical predictions. The results in a keratoconic subject, also corrected with adaptive optics, showed that important benefits are obtained despite decentrations in highly aberrated eyes.


Assuntos
Olho/fisiopatologia , Lentes , Transtornos da Visão/fisiopatologia , Transtornos da Visão/terapia , Humanos , Modelos Teóricos , Rotação
9.
J Vis ; 1(1): 1-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12678609

RESUMO

The objective was to study the relative contribution of the optical aberrations of the cornea and the internal ocular optics (with the crystalline lens as the main component) to overall aberrations in the human eye. Three sets of wave-front aberration data were independently measured in the eyes of young subjects: for the anterior surface of the cornea, the complete eye, and internal ocular optics. The amount of aberration of both the cornea and internal optics was found to be larger than for the complete eye, indicating that the first surface of the cornea and internal optics partially compensate for each other's aberrations and produce an improved retinal image. This result has a number of practical implications. For example, it shows the limitation of corneal topography as a guide for new refractive procedures and provides a strong endorsement of the value of ocular wave-front sensing for those applications.


Assuntos
Córnea/fisiologia , Cristalino/fisiologia , Distorção da Percepção/fisiologia , Percepção Visual/fisiologia , Acomodação Ocular/fisiologia , Adulto , Humanos , Retina/fisiologia , Acuidade Visual/fisiologia
10.
An Med Interna ; 18(12): 624-8, 2001 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-11852497

RESUMO

OBJECTIVE: A retrospective study of the correlation between CD4 lymphocytes and the viral load in 16 HIV-patients with tuberculosis. MATERIAL AND METHODS: The clinical forms of presentation of tuberculosis were classified according to the location/s of the disease into: pulmonary, distinguishing between typical pulmonary and atypical according to the radiological pattern; extrapulmonary; mixed forms: pulmonary and extrapulmonary; and miliary tuberculosis. RESULTS: Tuberculosis was exclusively pulmonary in 7 cases (44%), all were atypical; extrapulmonary 6 (38%); mixed 2 (12%); and miliary 1 (6%). The mean CD4 lymphocyte count was 111.1 (range 5-360), in 11 (69%) the counts were below 200 cells/mm3. The lowest CD4 count was in the mixed forms with a mean of 45 cells/mm3 whilst the highest was obtained in pulmonary forms with a mean of 128.3 cells/mm3. The mean viral load was 4.82 log (range, 0-5.93), the highest load was for mixed forms with a mean 5.69 log, whereas the lowest load was for pulmonary forms with a mean of 4.19 log. No significant correlation was observed between CD4 lymphocytes and viral load (correlation coefficient--0.1163). CONCLUSIONS: Though no significant correlation was observed, a high CD4 was associated to a low viral load and inversely a low CD4 with a high viral load.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/imunologia , Infecções por HIV/imunologia , Tuberculose/imunologia , Adulto , Contagem de Linfócito CD4 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Carga Viral
11.
J Refract Surg ; 16(5): S554-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11019871

RESUMO

There is currently considerable debate concerning the visual impact of correcting the higher order aberrations of the eye. We describe new measurements of a large population of human eyes and compute the visual benefit of correcting higher order aberrations. We also describe the increase in contrast sensitivity when higher order aberrations are corrected with an adaptive optics system. All these results suggest that many, though not all, observers with normal vision would receive worthwhile improvements in spatial vision from customized vision correction, at least over a range of viewing distances and particularly when the pupils are large. Keratoconic patients or patients suffering from spherical aberration as a result of laser refractive surgery as it is presently performed would especially benefit. These results encourage the development of methods to correct higher order aberrations.


Assuntos
Sensibilidades de Contraste/fisiologia , Erros de Refração/terapia , Acuidade Visual/fisiologia , Córnea/fisiopatologia , Humanos , Erros de Refração/fisiopatologia , Retina/fisiopatologia
12.
J Opt Soc Am A Opt Image Sci Vis ; 17(10): 1697-702, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11028517

RESUMO

We investigated how the optical aberrations associated with the anterior surface of the human cornea change with age in a normal population. Aberrations were computed for a central part of the cornea (4, 5, and 6 mm in diameter) from the elevation data provided by a videokeratographic system. Measurements were obtained in 59 normal healthy, near-emmetropic [spherical equivalent lower than 2 diopters (D)] subjects of three age ranges: younger (20-30 years old), middle-aged (40-50 years old), and older (60-70 years old). The average corneal radius decreased with age and the cornea became more spherical. As a consequence, spherical aberration was significantly larger in the middle-aged and older corneas. Coma and other higher-order aberrations also were correlated with age. The root mean square of the wave aberration exhibited a linear positive correlation (P < 0.003) with age for the three ranges of pupil diameter. Despite a large intersubject variability, the average amount of aberration in the human cornea tends to increase moderately with age. However, this increase alone is not enough to explain the substantial reduction previously found in retinal image quality with age. The change in the aberrations of the lens with age and the possible loss of part of the balance between corneal and lenticular aberrations in youth may be the main factors responsible for the reduction of retinal image quality through the life span.


Assuntos
Envelhecimento/fisiologia , Córnea/fisiologia , Óptica e Fotônica , Adulto , Idoso , Córnea/crescimento & desenvolvimento , Topografia da Córnea , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Pupila , Valores de Referência
13.
J Opt Soc Am A Opt Image Sci Vis ; 17(6): 955-65, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10850465

RESUMO

A procedure to calculate the wave aberration of the human cornea from its surface shape measured by videokeratography is presented. The wave aberration was calculated as the difference in optical path between the marginal rays and the chief ray refracted at the surface, for both on- and off-axis objects. The corneal shape elevation map was obtained from videokeratography and fitted to a Zernike polynomial expansion through a Gram-Schmidt orthogonalization. The wave aberration was obtained also as a Zernike polynomial representation. The accuracy of the procedure was analyzed. For calibrated reference surface elevations, a root-mean-square error (RMSE) of 1 to 2 microm for an aperture 4-6 mm in diameter was obtained, and the RMSE associated with the experimental errors and with the fitting method was 0.2 microm. The procedure permits estimation of the corneal wave aberration from videokeratoscopic data with an accuracy of 0.05-0.2 microm for a pupil 4-6 mm in diameter, rendering the method adequate for many applications.


Assuntos
Córnea/patologia , Topografia da Córnea/normas , Estudos de Avaliação como Assunto , Humanos , Modelos Biológicos , Lágrimas/fisiologia
14.
Vision Res ; 39(2): 207-17, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10326131

RESUMO

Off-axis monochromatic aberrations in the human eye impose limits on peripheral vision. However, the magnitude of the aberrations off-axis, and in particular coma, has not been yet completely determined. We have developed a procedure to estimate third order aberrations in the periphery of the human eye. The technique is based on recording series of double pass retinal images with unequal entrance and exit pupil diameters (Artal, Iglesias, López-Gil & Green (1995b). J. Opt. Soc. Am. A, 12, 2358-2366.) which allows the odd asymmetries in the retinal image be assessed. The procedure that is described provides accurate estimates of the main off-axis aberrations: astigmatism, defocus and coma. We have measured these aberrations in four normal subjects. For a given eccentricity, the measured amount of coma and astigmatism are relatively similar among subjects, because the angular distance from the axis is the dominant factor in determining the magnitude of these aberrations. However, we found considerable variability in the values of peripheral defocus, probably due to a complicate combination of off-axis aberrations and fundus shape. The final off-axis optical performance of the eye for a given object location is determined by a particular mixture of defocus, astigmatism, coma and higher order aberrations.


Assuntos
Erros de Refração/diagnóstico , Testes Visuais/métodos , Astigmatismo/diagnóstico , Simulação por Computador , Humanos , Modelos Biológicos
15.
Invest Ophthalmol Vis Sci ; 40(1): 203-13, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9888445

RESUMO

PURPOSE: To determine the average optical performance of the human eye, in terms of the modulation transfer function (MTF), as a function of age. METHODS: An apparatus was constructed to measure the ocular MTF, based on the recording of images of a green, 543-nm laser-point source after reflection in the retina and double pass through the ocular media. MTFs were computed from the average of three 4-second-exposure double-pass images recorded by a slow-scan, cooled charge-coupled device camera. The ocular MTF was measured for three artificial pupil diameters (3 mm, 4 mm, and 6 mm) with paralyzed accommodation under the best refractive correction in 20 subjects for each of three age categories: young subjects aged 20 to 30 years, middle-aged subjects aged 40 to 50 years, and older subjects aged 60 to 70 years. The selected subjects passed an ophthalmologic examination, excluding subjects with any form of ocular or retinal disease, spherical or cylindrical refractive errors exceeding 2 D, and corrected visual acuity lower than 1 (0.8 in the older age group). RESULTS: The average MTF was determined for each age group and pupil diameter. A two-parameter analytical expression was proposed to represent the average MTF in each age group for every pupil diameter. The ocular MTFs declined as age increased from young to older groups. The SD of the MTF results within age groups was lower than the differences between the mean for each group. CONCLUSIONS: The average optical performance of the human eye progressively declines with age. These MTF results can serve as a reference for determining mean ocular optics according to age.


Assuntos
Envelhecimento/fisiologia , Retina/fisiologia , Visão Ocular/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pupila/fisiologia
16.
Eur J Biochem ; 252(2): 314-24, 1998 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-9523703

RESUMO

Two cDNA clones, pTaM13.38 and pTd14.13.2, encoding a Triticum aestivum and a Triticum durum thioredoxin h, respectively, were isolated from mid-maturation seed cDNA libraries. The T aestivum thioredoxin h has a molecular mass of 13.5 kDa and that from T durum has a molecular mass of 13.8 kDa. These two wheat thioredoxin h are 98.5% similar and contain the canonical WCGPC active site and the important structural and functional amino acids that are conserved in thioredoxin sequences. The recombinant T. aestivum thioredoxin h (TrxTa) overproduced in BL21(DE3)pLysS was purified to homogeneity by a three-step procedure including heat treatment, anion-exchange chromatography and gel filtration. TrxTa showed a lower stability to high temperature than Escherichia coli thioredoxin or plant thioredoxin m. The molecular mass of TrxTa, determined by mass spectrometry, is 13,391 Da and corresponds to a protein lacking the first methionine residue, as confirmed by its N-terminal end sequence AASAAT. Using the 5,5'-dithiobis(2-nitrobenzoic acid)-reduction assay and monobromobimane revelation we showed that TrxTa is specifically reduced by wheat NADP:thioredoxin reductase (NTR), and not by E. coli NTR. TrxTa is able to reduce identified target proteins i.e. wheat seed alpha-amylase inhibitors (chloroform/methanol-soluble proteins). The presence of a putative transmembrane domain at the N-terminal end of the two wheat thioredoxins raises the question of whether these proteins are membrane anchored.


Assuntos
Tiorredoxinas/química , Triticum/química , Sequência de Aminoácidos , Sequência de Bases , Compostos Bicíclicos com Pontes/metabolismo , Clonagem Molecular , Dissulfetos/metabolismo , Ácido Ditionitrobenzoico/metabolismo , Escherichia coli/genética , Corantes Fluorescentes/metabolismo , Cinética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Proteínas de Plantas/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Tiorredoxina Dissulfeto Redutase/metabolismo
17.
Opt Lett ; 23(21): 1713-5, 1998 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-18091893

RESUMO

The relative contributions of optical aberrations of the cornea and the crystalline lens to the final image quality of the human eye were studied. The aberrations of the entire eye were obtained from pairs of double-pass retinal images, and the aberrations of the cornea were obtained from videokeratographic data. Third-order spherical aberration and coma were significantly larger for the cornea than for the complete eye, indicating a significant role of the lens in compensating for corneal aberrations. In a second experiment retinal images were recorded in an eye before and after we neutralized the aberrations of the cornea by having the subjects wear swimming goggles filled with saline water, providing a direct estimate of the optical performance of the crystalline lens.

18.
DNA Seq ; 5(3): 153-62, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7612926

RESUMO

The CM (chloroform-methanol-soluble) proteins are low-molecular-weight cysteine-rich proteins that are found in wheat and barley endosperms. A cDNA clone encoding a Triticum durum (T. durum) CM3 protein has been isolated from a mid-maturation seed cDNA library. The T. durum CM3 protein is synthesized as a precursor including a signal peptide (SP) of 25 residues. Northern blot analysis shows that in developing seed the highest level of CM3 protein mRNA is detected at mid-maturation. The hybridization patterns obtained by Southern blot analysis indicated that T. durum CM proteins are encoded by a small multigene family. The similarity between the wheat and barley CM proteins encoded by homologous chromosomes is much higher than that between each of the three members of the T. durum family. All CM proteins contain ten cysteine residues organized in a conserved cysteine motif.


Assuntos
Proteínas de Plantas/química , Proteínas de Plantas/genética , Triticum/genética , Inibidores da Tripsina/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Códon/genética , Regulação da Expressão Gênica de Plantas , Hordeum/genética , Dados de Sequência Molecular , Família Multigênica , Proteínas de Plantas/biossíntese , RNA Mensageiro/análise , Sementes/genética , Homologia de Sequência do Ácido Nucleico , Fatores de Tempo , Triticum/metabolismo
19.
Plant Mol Biol ; 25(1): 43-57, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7516201

RESUMO

From a mid-maturation seed cDNA library we have isolated cDNA clones encoding two Triticum aestivum puroindolines. Puroindoline-a and puroindoline-b, which are 55% similar, are basic, cystine-rich and tryptophan-rich proteins. Puroindolines are synthesized as preproproteins which include N- and C-terminal propeptides which could be involved in their vacuolar localization. The mature proteins have a molecular mass of 13 kDa and a calculated isoelectric point greater than 10. A notable feature of the primary structure of puroindolines is the presence of a tryptophan-rich domain which also contains basic residues. A similar tryptophan-rich domain was found within an oat seed protein and a mammalian antimicrobial peptide. The ten cysteine residues of puroindolines are organized in a cysteine skeleton which shows similarity to the cysteine skeleton of other wheat seed cystine-rich proteins. Northern blot analysis showed that puroindoline genes are specifically expressed in T. aestivum developing seeds. No puroindoline transcripts as well as no related genes were detected in Triticum durum. The identity of puroindolines to wheat starch-granule associated proteins is discussed as well as the potential role of puroindolines in the plant defence mechanism.


Assuntos
Proteínas de Plantas/genética , Triticum/genética , Sequência de Aminoácidos , Sequência de Bases , DNA/isolamento & purificação , DNA Complementar/química , Grão Comestível/química , Regulação da Expressão Gênica , Dados de Sequência Molecular , Proteínas de Plantas/biossíntese , Proteínas de Plantas/química , Precursores de Proteínas/química , RNA/isolamento & purificação , Sementes/genética , Homologia de Sequência de Aminoácidos , Triticum/química , Triticum/crescimento & desenvolvimento
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