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1.
Theor Appl Genet ; 106(7): 1316-25, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12748784

RESUMEN

In order to get an overview on the genetic relatedness of sorghum (Sorghum bicolor) landraces and cultivars grown in low-input conditions of small-scale farming systems, 46 sorghum accessions derived from Southern Africa were evaluated on the basis of amplified fragment length polymorphism (AFLPs), random amplified polymorphic DNAs (RAPDs) and simple sequence repeats (SSRs). By this approach all sorghum accessions were uniquely fingerprinted by all marker systems. Mean genetic similarity was estimated at 0.88 based on RAPDs, 0.85 using AFLPs and 0.31 based on SSRs. In addition to this, genetic distance based on SSR data was estimated at 57 according to a stepwise mutation model (Deltamu-SSR). All UPGMA-clusters showed a good fit to the similarity estimates (AFLPs: r = 0.92; RAPDs: r = 0.88; SSRs: r = 0.87; Deltamu-SSRs: r = 0.85). By UPGMA-clustering two main clusters were built on all marker systems comprising landraces on the one hand and newly developed varieties on the other hand. Further sub-groupings were not unequivocal. Genetic diversity (H, DI) was estimated on a similar level within landraces and breeding varieties. Comparing the three approaches to each other, RAPD and AFLP similarity indices were highly correlated (r = 0.81), while the Spearman's rank correlation coefficient between SSRs and AFLPs was r = 0.57 and r = 0.51 between RAPDs and SSRs. Applying a stepwise mutation model on the SSR data resulted in an intermediate correlation coefficient between Deltamu-SSRs and AFLPs (r = 0.66) and RAPDs ( r = 0.67), respectively, while SSRs and Deltamu-SSRs showed a lower correlation coefficient (r = 0.52). The highest bootstrap probabilities were found using AFLPs (56% on average) while SSR, Deltamu-SSR and RAPD-based similarity estimates had low mean bootstrap probabilities (24%, 27%, 30%, respectively). The coefficient of variation (CV) of the estimated genetic similarity decreased with an increasing number of bands and was lowest using AFLPs.


Asunto(s)
Marcadores Genéticos , Variación Genética , Sorghum/genética , África Austral , Secuencia de Bases , Análisis por Conglomerados , Cartilla de ADN
2.
Thorac Cardiovasc Surg ; 39(6): 384-5, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1788846

RESUMEN

The successful resection of an abdominal aortic aneurysm is presented in a patient who had undergone kidney transplantation 4 years previously. Because the transplanted kidney is more sensitive to ischemia than a normal one, a femoro-femoral bypass with a pump oxygenator was used for perfusion of the transplanted kidney during crossclamping. During the clamping time of 40 minutes kidney perfusion was maintained with a perfusion pressure of 60 to 80 mmHg and the flow was 600 to 1000 ml/min. A collagen-seeded Dacron graft (diameter: 18 mm, length: 12 mm) was interposed. The postoperative course was uncomplicated. We believe that performing the femoro-femoral bypass with a pump oxygenator is an effective and simple method for kidney protection in such operations.


Asunto(s)
Aneurisma de la Aorta/cirugía , Circulación Extracorporea/métodos , Trasplante de Riñón , Aorta Abdominal/cirugía , Humanos , Masculino , Persona de Mediana Edad , Oxigenadores
3.
Thorac Cardiovasc Surg ; 37(2): 76-9, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2727984

RESUMEN

Post myocardial infarction recurrent ventricular arrhythmias are usually coupled with depressed left ventricular function. We have until recently employed the most widely used surgical techniques such as endocardial resection, cryosurgery and isolation. After these methods had failed in a patient with an extensive septal focus, it finally became possible to effectively ablate the arrhythmogenic area by injection of 10 ml 95% alcohol subendocardially. The following experimental studies were carried out to investigate the effect of direct injection of alcohol on the myocardicytes. 95% alcohol, injected into the apex of the left ventricle of Wistar rats weighing between 150 and 200 g caused extensive coagulation necrosis 5 minutes after injection, as was revealed by histological examination. The site of injection showed marked scar formation after 6 months. On the basis of these findings, 4 more patients were treated successfully with alcohol, which was directly injected subendocardially without endocardial resection using a long needle. The advantage of this procedure is that resection can be avoided, particularly in critical areas such as the septum and regions around papillary muscles.


Asunto(s)
Etanol/administración & dosificación , Ventrículos Cardíacos/efectos de los fármacos , Taquicardia/tratamiento farmacológico , Fibrilación Ventricular/tratamiento farmacológico , Animales , Enfermedad Coronaria/complicaciones , Electrocardiografía , Sistema de Conducción Cardíaco/efectos de los fármacos , Ventrículos Cardíacos/patología , Humanos , Inyecciones , Necrosis , Ratas , Recurrencia
4.
Thorac Cardiovasc Surg ; 30(6): 354-7, 1982 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6187092

RESUMEN

During a period of 4 years, 32 patients with acute bacterial endocarditis were admitted for cardiac surgical intervention. Uncontrollable infections, heart failure or embolism presented indications for the operation. In all cases, a preoperative, invasive angiography diagnostic was abandoned. The indication for surgical intervention was based on clinical criteria as well as the findings of one-dimensional or two-dimensional echocardiography. In 26 out of 32 patients who underwent surgical intervention, the preoperative echocardiography findings were in agreement with the intraoperative findings. In the remaining 6 patients, the preoperative echocardiographic findings were incomplete; in 2 cases particularly, it is important to note that an aneurysm of the ascending aorta had been missed. In view of these findings and results, we think that in acute bacterial endocarditis, the combined use of one- and two-dimensional echocardiography together with clinical findings can replace preoperative hemodynamic diagnostics.


Asunto(s)
Ecocardiografía , Endocarditis Bacteriana/diagnóstico , Enfermedades de las Válvulas Cardíacas/cirugía , Prótesis Valvulares Cardíacas , Adulto , Anciano , Sangre/microbiología , Endocarditis Bacteriana/microbiología , Endocarditis Bacteriana/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios , Infecciones Estafilocócicas/diagnóstico , Streptococcaceae
5.
Pathol Res Pract ; 173(3): 294-302, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-7122322

RESUMEN

The basic issue in our project was to quantify the age-process in the human hypophysis-gonadal system. Of the many aspects of aging, we estimated, using human autopsy material, the content of desoxyribonucleic acid (DNA), of hydroxyproline, of hexosamines and of uronic acids in the hypophysis, testis, and ovary. The respective organs were weighed and homogenised in acid-buffer solution after which, for each of the parameters, 1.0 ml of homogenate was extracted and processed: DNA-estimation according to modified Dische/Seibert (1929) method; hydroxy-proline according to Stegemann and Stalder (1967); hexosamines and uronic acids according to Gatt and Berman (1966) and Blumenkrantz and Asboe-Hansen (1973) respectively. All values obtained were expressed in micrograms/ml of homogenate. The age investigated ranged from a few days old to 99 years. The DNA-curves for the hypophysis initially showed a decline till about the third decade of life and then remained almost constant with a significant decline up to the senile age. The DNA-curves for the testis and ovary demonstrated a sharp decline initially till the third decade of life, after which the curves remained constant, but showed reduction during higher age. Similar pattern of distribution was also observed for hexosamines, and uronic acids: after the initial decline of uronic acids in the human hypophysis and testis during the first three decades of life and nearly constant values thereafter, hexosamines, together with the uronic acids show minimal decrease in content during the senile period. Contents od hydroxyproline significantly increased in testis, ovary and hypophysis with aging. This biochemically proven age-fibrosis in the human gonads corresponds to the morphologically observed vascular and interstitial sclerosis in the testis and the ovary and may partly help to explain the declined sensitivity of these target organs to hypophyseal stimulation during the aging period.


Asunto(s)
Ovario/análisis , Hipófisis/análisis , Testículo/análisis , Adolescente , Adulto , Factores de Edad , Anciano , Niño , Preescolar , Tejido Conectivo/análisis , ADN/análisis , Femenino , Hexosaminas/análisis , Humanos , Hidroxiprolina/análisis , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Ácidos Urónicos/análisis
6.
Mech Ageing Dev ; 14(3-4): 325-31, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-7193785

RESUMEN

In any given phase of the age process, the rates of synthesis and degradation of collagen and other macromolecules are diversely influenced by changes in the respective enzyme activities. This naturally affects and reflects the contents of the intracellular as well as extracellular macromolecules. In our studies, the total contents of desoxyribonucleic acid (DNA), hydroxyproline, hexosamines and uronic acids of the four compartments of the human heart were estimated and plotted against age. The results obtained for DNA showed an initial rapid decline in its content to about the middle of the third decade of life, i.e. around the end of the maturation period. Thereafter, the DNA curves showed a relatively slower decrease until the fifth decade, after which a slight increase was observed during senescence. This holds for both the left and the right sides of the heart. Hydroxyproline levels, on the other hand, remained unchanged in all the different compartments except in the left atrium, where the initial phase of the curve showed a significant drop until the middle of the fourth decade. Hydroxyproline values in the atria were twice as high as in the ventricles, which in turn showed higher levels of hexosamines than uronic acids. Both hexosamines and uronic acids in the atrial walls showed an initial decline followed by a gradual rise during ageing. Contents of uronic acids in the ventricles showed a gradual but steady rise throughout life.


Asunto(s)
Tejido Conectivo/fisiología , ADN/análisis , Corazón/crecimiento & desarrollo , Adolescente , Adulto , Anciano , Envejecimiento , Niño , Preescolar , Colágeno/análisis , Crecimiento , Atrios Cardíacos/crecimiento & desarrollo , Ventrículos Cardíacos/crecimiento & desarrollo , Hexosaminas/análisis , Humanos , Hidroxiprolina/análisis , Lactante , Persona de Mediana Edad , Ácidos Urónicos/análisis
7.
Aktuelle Gerontol ; 8(8): 427-39, 1978 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-29508

RESUMEN

The DNA-content of brain, testis and ovar of Wistar rats (inbred strain) was quantitatively analysed. We observed no significant differences between the several parts of the cerebrum, but between the cerebrum and the cerebellum. Furthermore we demonstrated alterations (with increase and decrease) of the DNA content of all brain parts as well as of testis and ovar during the course of life of this Wistar rat strain. These results and further investigations of the water content as well as of the absolute and of the relative weight of brains of these rats (in comparison to humans) extend the data and our knowledge about these subjects. It is possible to differentiate growth phases (by means of the DNA assays, which correlate with the morphologically well defined growth phases. Finally these results are fundamentals and presuppositions for investigations of the production metabolism of these organs because the DNA content is a better parameter (reference or relation figure, resp.) than the dry or wet weights and the protein or the nitrogen contents.


Asunto(s)
Envejecimiento , Química Encefálica , ADN/análisis , Ovario/análisis , Testículo/análisis , Adulto , Anciano , Animales , Encéfalo/anatomía & histología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Ovario/anatomía & histología , Ratas , Ratas Endogámicas , Testículo/anatomía & histología
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