Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 69
Filtrar
1.
J Biol Chem ; 275(26): 19475-81, 2000 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-10777505

RESUMEN

Lipid phosphorylation takes place within the chloroplast envelope. In addition to phosphatidic acid, phosphatidylinositol phosphate, and their corresponding lyso-derivatives, we found that two novel lipids underwent phosphorylation in envelopes, particularly in the presence of carrier-free [gamma-(32)P]ATP. These two lipids incorporated radioactive phosphate in chloroplasts in the presence of [gamma-(32)P]ATP or [(32)P]P(i) and light. Interestingly, these two lipids were preferentially phosphorylated in envelope membranes in the presence [gamma-(32)P]CTP, as the phosphoryl donor, or [gamma-(32)P]ATP, when supplemented with CDP and nucleoside diphosphate kinase II. The lipid kinase activity involved in this reaction was specifically inhibited in the presence of cytosine 5'-O-(thiotriphosphate) (CTPgammaS) and sensitive to CTP chase, thereby showing that both lipids are phosphorylated by an envelope CTP-dependent lipid kinase. The lipids were identified as phosphorylated galactolipids by using an acid hydrolysis procedure that generated galactose 6-phosphate. CTPgammaS did not affect the import of the small ribulose-bisphosphate carboxylase/oxygenase subunit into chloroplasts, the possible physiological role of this novel CTP-dependent galactolipid kinase activity in the chloroplast envelope is discussed.


Asunto(s)
Cloroplastos/metabolismo , Citidina Trifosfato/metabolismo , Membranas Intracelulares/metabolismo , Metabolismo de los Lípidos , Fosfotransferasas/metabolismo , Cloroplastos/efectos de los fármacos , Cromatografía en Capa Delgada , Diglicéridos/farmacología , Relación Dosis-Respuesta a Droga , Galactolípidos , Galactosa/farmacología , Glucolípidos/metabolismo , Glucolípidos/farmacología , Hidrólisis , Fosforilación , Spinacia oleracea/química , Termolisina/farmacología , Tilacoides/metabolismo , Factores de Tiempo
2.
Eur J Pediatr Surg ; 8(1): 4-8, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9550268

RESUMEN

Four cases of an until now undescribed syndrome have been observed in Berne in the last 40 years. All four cases are members of the same family and have occurred in three consecutive generations. They present with a U-shaped palatal cleft, microstomia, hypoplasia of the mandibula and a partial anodontia. An autosomal dominant heredity was demonstrated. Karyograms have been made in three of the patients and in all patients showed an anomaly in the form of a "fragile site" in one chromosome (16 fra 16 [q22]). Surgical and orthopedic treatments were difficult.


Asunto(s)
Anomalías Múltiples/genética , Anodoncia/genética , Fisura del Paladar/genética , Micrognatismo/genética , Microstomía/genética , Adulto , Sitios Frágiles del Cromosoma , Fragilidad Cromosómica , Cromosomas Humanos Par 16 , Femenino , Genes Dominantes , Humanos , Lactante , Recién Nacido , Cariotipificación , Masculino , Linaje , Síndrome
3.
Biochim Biophys Acta ; 1233(2): 123-33, 1995 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-7865537

RESUMEN

The transfer of organelle of newly synthesized lipid molecules from inner envelope to thylakoid membranes, as well as their subsequent transbilayer distribution in these membranes, have been studied in intact chloroplasts isolated from young and mature spinach, young pea and mature lettuce leaves, using a recently developed methodology (Rawyler, A., Meylan, M. and Siegenthaler, P.A. (1992) Biochim. Biophys. Acta 1104, 331-341). Three radiolabelled precursors were used. UDP-[14C]galactose allowed to follow the fate of mono- and digalactosyldiacylglycerol (MGDG and DGDG) made from polyunsaturated, preexisting diacylglycerol (DAG), whereas [14C]acetate and [14C]glycerol 3-phosphate were used to follow the fate of MGDG and phosphatidylglycerol (PG), respectively, after de novo synthesis. MGDG, DGDG and PG molecules assembled at the envelope level were found to be exportable to thylakoids in amounts strictly proportional to the amounts synthesized, provided that the necessary substrates were not limiting. Lipid export was class-selective; under our conditions, as much as 50-80% of the MGDG, 87% of the PG and 20-30% of the DGDG synthesized were exported to thylakoids. However, within the MGDG class labelled from [14C]acetate, there was hardly any selectivity in the export of its various molecular species. For MGDG, the proportionality coefficient, which reflects the efficiency of the export process, was higher in chloroplasts from young than from mature leaves, and higher in spinach than in pea and lettuce. Temperature affected the efficiency of galactolipid export in a class-dependent way. MGDG synthesis and export had similar Q10 values of about 4 in young and 3 in mature spinach leaves, while the Q10 of DGDG export was higher than that of its synthesis. In most cases, the transmembrane distribution of labelled lipids in thylakoids was found to match closely the corresponding distribution of mass, regardless of plant age and species and of incubation time and temperature. In some cases however, small but significant differences occurred between the label and the mass transbilayer distributions of MGDG (labelled molecules more inwardly oriented), DGDG and PG (more outwardly oriented). We propose a general model in which the thylakoid lipid asymmetry is primarily preestablished in the chloroplast envelope by the topography of its lipid-synthesizing enzymes, together with the occurrence of relatively fast lateral diffusion and translocation rates of the newly synthesized lipids. Transient fusions between inner envelope and thylakoid membranes would allow lipid export by lateral diffusion and build the observed lipid asymmetry in the latter.


Asunto(s)
Cloroplastos/metabolismo , Lípidos de la Membrana/metabolismo , Factores de Edad , Transporte Biológico , Galactosa/metabolismo , Glucolípidos/metabolismo , Membranas Intracelulares/metabolismo , Membranas Intracelulares/ultraestructura , Lactuca , Pisum sativum , Spinacia oleracea
5.
Tissue Cell ; 22(1): 93-100, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2326791

RESUMEN

Allogenic, demineralized bone powder (DBP) was implanted into rat rectus abdominis muscle to induce osteoneogenesis. The main induction steps are invasion of the implant by host mesenchyme cells, differentiation of cartilage, invasion by blood capillaries or angiogenesis, differentiation of osteoblasts and bone marrow. The result is the formation of a cancellous ossicle. Giant polykarions appear in the implant after calcification of the cartilage matrix. As the DBP particles are not resorbed in the implant, these polykarions could either be foreign body giant cells brought about in reaction to foreign matrix or chondroclasts which resorb the cartilage. The results obtained by histological and histochemical methods (McNeals-von Kossa stain, tartrate resistant acid phosphatase reaction), as well as ultrastructural studies, lead to the conclusion that these large polynucleated cells are chondroclasts.


Asunto(s)
Cartílago/citología , Células Gigantes de Cuerpo Extraño/citología , Células Gigantes/citología , Osteogénesis/fisiología , Animales , Matriz Ósea/fisiología , Matriz Ósea/trasplante , Matriz Ósea/ultraestructura , Cartílago/ultraestructura , Células Gigantes de Cuerpo Extraño/ultraestructura , Masculino , Ratas , Ratas Endogámicas
6.
Z Kinderchir ; 43(3): 224-8, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3046171

RESUMEN

A 6 1/2-year-old child was admitted to the emergency ward for third degree burn injuries representing 40% of body surface. Shock therapy was first applied. After débridement and in a series of operating sessions hands were grafted with full-thickness skin and most other wounds were covered with mesh grafts. On the 14th day after admission a piece of approximately 5 cm2 split thickness scalp skin was used to expand the keratinocytes by cell culture techniques according to the method of Rheinwald and Green (7). After 20 days 4 sheets of cells of first subculture, each 10 cm in diameter, representing a surface of approximately 300 cm2, were implanted on the front of the left thigh, which was burnt third-degree deep. Light microscopy of punch biopsies from mesh grafted and keratinocyte implanted sites taken 5 months after grafting showed a well differentiated epidermis overlying scar tissue. The following conclusions were drawn: Autologous keratinocytes did take on a third degree wound. No basic difference was observed neither clinically nor histologically between mesh-grafted and keratinocyte-implanted sites. The epidermis formed by keratinocyte implantation lacked pigmentation but presented an aesthetically better appearance than the mesh-graft treated sites. Given the scarcity of donor sites and the results obtained by implanting keratinocyte cultures, this latter technique may be resorted to in any extended and deep burn injury.


Asunto(s)
Quemaduras/cirugía , Trasplante de Piel , Células Cultivadas , Niño , Femenino , Supervivencia de Injerto , Humanos , Mallas Quirúrgicas , Cicatrización de Heridas
7.
Eur Urol ; 15(3-4): 235-6, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3215257

RESUMEN

Granular cystitis or 'papular cystitis' is a very common form of cystitis in young girls. In this paper we show the evolution of this affliction in women after puberty. In a series we were able to follow up leukoplakia or follicular cystitis patients to the age of 16 years.


Asunto(s)
Cistitis/patología , Leucoplasia/patología , Neoplasias de la Vejiga Urinaria/patología , Vejiga Urinaria/patología , Adolescente , Adulto , Biopsia , Niño , Cistoscopía , Femenino , Estudios de Seguimiento , Humanos , Factores de Tiempo
8.
Cleft Palate J ; 24(4): 291-8, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3479275

RESUMEN

According to the literature (Schweckendiek, 1955; Malek and Psaume, 1983), early closure of the soft palate is a factor in the development of better phonation. The reason for this favorable outcome is not yet known with any certainty. One of the factors may be the volume of the epipharynx, which depends on the distance between the pterygoid processes and their orientation in space. The measurement of the interpterygoid distance, the calculation of the pterygomandibular index, and the measurement of the pterygoid abduction angle, all by means of computerized tomography (CT) scanning, show that early closure of the soft palate results in significant reduction of the interpterygoid distance and in total correction of the divergence of the pterygoid processes.


Asunto(s)
Fisura del Paladar/cirugía , Paladar Blando/cirugía , Faringe/diagnóstico por imagen , Hueso Esfenoides/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Fisura del Paladar/diagnóstico por imagen , Humanos , Lactante , Mandíbula/diagnóstico por imagen , Mandíbula/patología , Paladar Blando/diagnóstico por imagen , Paladar Blando/patología , Faringe/patología , Estudios Prospectivos , Distribución Aleatoria , Hueso Esfenoides/patología , Factores de Tiempo
9.
J Pediatr Surg ; 22(9): 877-9, 1987 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3668779

RESUMEN

An intestinal segment through staged augmentation of its blood supply can be well suited to bridge a gap in the esophagus from the abdomen to the neck.


Asunto(s)
Esofagoplastia/métodos , Intestino Delgado/cirugía , Anastomosis Quirúrgica , Femenino , Humanos , Lactante , Intestino Delgado/irrigación sanguínea , Trasplante Autólogo , Procedimientos Quirúrgicos Vasculares
10.
Z Kinderchir ; 42(2): 115-9, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3591007

RESUMEN

Cloacal malformations in female infants are not very common and their treatment is most challenging because every case differs from the others. In the light of a well-documented case, the authors describe the complexity of the malformation, the difficulties of making a correct detailed diagnosis, and the chronology of repair. They stress the advantage of the posterior sagittal approach for the first part of the operation, changing for the second part to a supine and later to a lithotomy position. In most cases a satisfactory reconstruction is possible, anatomically as well as functionally.


Asunto(s)
Cloaca/anomalías , Abdomen/cirugía , Ano Imperforado/cirugía , Cloaca/cirugía , Femenino , Estudios de Seguimiento , Humanos , Lactante , Lipoma/cirugía , Perineo/cirugía , Ureterocele/cirugía , Vagina/anomalías , Vagina/cirugía
11.
Eur Urol ; 13(3): 182-5, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3609097

RESUMEN

The syndrome of glomerular immaturity associated with renal tubular acidosis and nephrocalcinosis or urolithiasis is illustrated by a case in which the diagnosis was made before the histological confirmation. Cases of urolithiasis in infants may be associated with this syndrome and attention must be paid to this rare but severe condition.


Asunto(s)
Acidosis Tubular Renal/diagnóstico , Glomérulos Renales/patología , Nefrocalcinosis/diagnóstico , Cálculos Urinarios/diagnóstico , Humanos , Lactante , Masculino , Síndrome
16.
Z Kinderchir ; 41(3): 167-70, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3526741

RESUMEN

New bone tissue can be induced anywhere in the animal organism, i.e. even at a site distant from actual bone, by the implantation of demineralised bone powder (DBP). Basic implantation experiments were first carried out and tested in the rat (Bettex-Galland 1985). The results led us to use the experience gained to treat four patients with bone defects with DBP (one bone cyst, and 3 chronic skull defects). The DBP used was prepared aseptically from fresh cadaver bone. The results were assessed by means of x-ray films and/or CT-scan, and the preliminary evaluation is encouraging.


Asunto(s)
Enfermedades Óseas/cirugía , Regeneración Ósea , Trasplante Óseo , Adolescente , Quistes Óseos/cirugía , Niño , Preescolar , Encefalocele/cirugía , Femenino , Fémur/cirugía , Liofilización , Humanos , Lactante , Masculino , Hueso Occipital/cirugía , Polvos , Fracturas Craneales/cirugía , Cicatrización de Heridas
17.
Prog Pediatr Surg ; 19: 103-13, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3081948

RESUMEN

Gastroesophageal reflux (GER) was looked for retro- and prospectively by various diagnostic methods in 67 patients, subdivided into three groups according to age at time of investigation. Pathological reflux was found in only one-quarter of the patients aged 16-23 years, but in three-quarters of both younger groups followed up for 1.5-14 years so far. Whereas pathological findings were most frequently disclosed by manometry in the older patients, radiological findings were most often decisive in younger patients. Following closure of recurrent tracheoesophageal fistulas and resection of anastomotic stenoses, eight patients developed reflux complications during the first months of life; these were so severe that antireflux plasty became unavoidable. Factors influencing the incidence of GER following esophageal repair were: the definition of GER based on the diagnostic method employed, the patient's age at the time of diagnosis, and anastomotic complications requiring a second operation. The essential time for treatment was the first year of life.


Asunto(s)
Atresia Esofágica/cirugía , Reflujo Gastroesofágico/etiología , Complicaciones Posoperatorias/etiología , Adolescente , Adulto , Niño , Preescolar , Estudios de Seguimiento , Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/terapia , Humanos
18.
Prog Pediatr Surg ; 18: 22-31, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-3927427

RESUMEN

From examinations and clinical observations of 40 infants and a varying number of children from 2 to 11 years who all had characteristic symptoms of gastroesophageal reflux (GER), an attempt was made to establish the diagnostic contribution of esophageal manometry and long-term pH monitoring. A correlation between decreased resting pressure (less than or equal to 12 mmHg), or a sphincter insufficiency, and the degree of reflux symptoms was completely absent in infancy and increased only very slightly in young children. The most influential pH monitoring parameters were reflux during sleep, beyond 2 h postprandial, and during crying. These correlated most with the symptoms in infants. On the other hand, clinical developments were independent of the extent of the pH monitoring findings.


Asunto(s)
Reflujo Gastroesofágico/diagnóstico , Niño , Preescolar , Esófago/fisiopatología , Reflujo Gastroesofágico/fisiopatología , Humanos , Concentración de Iones de Hidrógeno , Lactante , Manometría , Monitoreo Fisiológico
20.
Z Kinderchir ; 38(4): 206-10, 1983 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-6637122

RESUMEN

Cardiomyotomy and fundoplication were performed in 7 children with achalasia of the oesophagus. They were followed up clinically, radiologically and manometrically from 7 to 18 years. Virtually all clinical symptoms and complaints disappeared immediately postoperatively and the patients remained free from symptoms well into adolescence except for very mild intermittent dysphagia in two of them. The residual mega-oesophagus and the disturbances of motility were least apparent in those operated on in early infancy. It may, therefore, be assumed that the motility pattern is more likely to return to normal in the oesophagus of the infant due to the relatively short period of dilatation. Fundoplication after Nissen did not alter the existing motility but was able to prevent gastro-oesophageal reflux and its possible grave consequences in all cases.


Asunto(s)
Acalasia del Esófago/cirugía , Unión Esofagogástrica/cirugía , Adolescente , Adulto , Cardias/cirugía , Niño , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Manometría
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA