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1.
J Geophys Res Planets ; 125(12): e2020JE006527, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33520561

RESUMEN

This paper provides an overview of the Curiosity rover's exploration at Vera Rubin ridge (VRR) and summarizes the science results. VRR is a distinct geomorphic feature on lower Aeolis Mons (informally known as Mount Sharp) that was identified in orbital data based on its distinct texture, topographic expression, and association with a hematite spectral signature. Curiosity conducted extensive remote sensing observations, acquired data on dozens of contact science targets, and drilled three outcrop samples from the ridge, as well as one outcrop sample immediately below the ridge. Our observations indicate that strata composing VRR were deposited in a predominantly lacustrine setting and are part of the Murray formation. The rocks within the ridge are chemically in family with underlying Murray formation strata. Red hematite is dispersed throughout much of the VRR bedrock, and this is the source of the orbital spectral detection. Gray hematite is also present in isolated, gray-colored patches concentrated toward the upper elevations of VRR, and these gray patches also contain small, dark Fe-rich nodules. We propose that VRR formed when diagenetic event(s) preferentially hardened rocks, which were subsequently eroded into a ridge by wind. Diagenesis also led to enhanced crystallization and/or cementation that deepened the ferric-related spectral absorptions on the ridge, which helped make them readily distinguishable from orbit. Results add to existing evidence of protracted aqueous environments at Gale crater and give new insight into how diagenesis shaped Mars' rock record.

2.
Anaesthesist ; 65(3): 198-202, 2016 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-26867603

RESUMEN

Central venous catheterization is an invasive procedure which can be associated with severe complications. These include in particular unsuccessful arterial puncture and vascular injuries, which in addition to loss of blood can lead to massive soft tissue swelling. A 63-year-old female patient developed massive cervical bleeding during ultrasound-guided internal jugular vein puncture and the rapidly enlarging hematoma led to compromisation of the airway. A cannot intubate, cannot ventilate situation developed and the subsequent hypoxia led to cardiac arrest that was only resolved after emergency surgical tracheotomy during cardiopulmonary resuscitation.


Asunto(s)
Cateterismo Venoso Central/efectos adversos , Vértebras Cervicales/lesiones , Hematoma/etiología , Reanimación Cardiopulmonar , Vértebras Cervicales/diagnóstico por imagen , Femenino , Paro Cardíaco/etiología , Paro Cardíaco/terapia , Hematoma/diagnóstico por imagen , Humanos , Venas Yugulares/lesiones , Persona de Mediana Edad , Seguridad del Paciente , Enfisema Subcutáneo/etiología , Traqueostomía , Ultrasonografía Intervencional
3.
Br J Pharmacol ; 172(11): 2814-26, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25573195

RESUMEN

BACKGROUND AND PURPOSE: Inhaled amiloride, a blocker of the epithelial sodium channel (ENaC), enhances mucociliary clearance (MCC) in cystic fibrosis (CF) patients. However, the dose of amiloride is limited by the mechanism-based side effect of hyperkalaemia resulting from renal ENaC blockade. Inhaled ENaC blockers with a reduced potential to induce hyperkalaemia provide a therapeutic strategy to improve mucosal hydration and MCC in the lungs of CF patients. The present study describes the preclinical profile of a novel ENaC blocker, NVP-QBE170, designed for inhaled delivery, with a reduced potential to induce hyperkalaemia. EXPERIMENTAL APPROACH: The in vitro potency and duration of action of NVP-QBE170 were compared with amiloride and a newer ENaC blocker, P552-02, in primary human bronchial epithelial cells (HBECs) by short-circuit current. In vivo efficacy and safety were assessed in guinea pig (tracheal potential difference/hyperkalaemia), rat (hyperkalaemia) and sheep (MCC). KEY RESULTS: In vitro, NVP-QBE170 potently inhibited ENaC function in HBEC and showed a longer duration of action to comparator molecules. In vivo, intratracheal (i.t.) instillation of NVP-QBE170 attenuated ENaC activity in the guinea pig airways with greater potency and duration of action than that of amiloride without inducing hyperkalaemia in either guinea pig or rat. Dry powder inhalation of NVP-QBE170 by conscious sheep increased MCC and was better than inhaled hypertonic saline in terms of efficacy and duration of action. CONCLUSIONS AND IMPLICATIONS: NVP-QBE170 highlights the potential for inhaled ENaC blockers to exhibit efficacy in the airways with a reduced risk of hyperkalaemia, relative to existing compounds.


Asunto(s)
Amilorida/análogos & derivados , Amilorida/farmacología , Células Epiteliales/efectos de los fármacos , Bloqueadores del Canal de Sodio Epitelial/farmacología , Hiperpotasemia/inducido químicamente , Depuración Mucociliar/efectos de los fármacos , Éteres Fenílicos/farmacología , Piperidinas/farmacología , Administración por Inhalación , Amilorida/efectos adversos , Animales , Bloqueadores del Canal de Sodio Epitelial/efectos adversos , Guanidinas , Cobayas , Técnicas In Vitro , Éteres Fenílicos/efectos adversos , Piperidinas/efectos adversos , Pirazinas , Ratas , Mucosa Respiratoria/citología , Ovinos
4.
Hum Gene Ther ; 12(3): 279-89, 2001 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-11177564

RESUMEN

Wolman disease is a lethal lysosomal storage disease due to deficiency of lysosomal acid lipase (LAL). Wolman disease is characterized by pronounced hepatic involvement while neurological symptoms are uncommon, making Wolman disease an attractive candidate for liver-directed gene therapy. This study was performed to test the effects of gene replacement in fibroblasts lacking LAL, using a recombinant adenovirus encoding the human LAL cDNA (AdhLAL). Human fibroblasts from a Wolman disease patient were infected with AdhLAL and showed a dose-dependent increase in LAL protein and activity up to 5-fold above levels in control fibroblasts. Furthermore, 72 hr after infection with AdhLAL there was a dose-dependent correction of the severe lipid storage phenotype of Wolman disease fibroblasts. Electron microscopy confirmed significant correction of the lysosomal lipid storage in AdhLAL-infected Wolman disease fibroblasts at the ultrastructural level. Intravenous injection of AdhLAL into wild-type mice resulted in a 13.5-fold increase in hepatic LAL activity, and overexpression of LAL was not associated with toxic side effects. These data demonstrate high-level lysosomal expression of recombinant LAL in vitro and in vivo and show the feasibility of gene therapeutic strategies for the treatment of Wolman disease.


Asunto(s)
Fibroblastos/metabolismo , Técnicas de Transferencia de Gen , Lipasa/metabolismo , Lisosomas/enzimología , Enfermedad de Wolman/enzimología , Enfermedad de Wolman/terapia , Adenoviridae/genética , Animales , Western Blotting , Células COS , Colesterol/metabolismo , ADN Complementario/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Fibroblastos/enzimología , Fibroblastos/ultraestructura , Terapia Genética , Humanos , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica , Fenotipo , Factores de Tiempo , Triglicéridos/metabolismo , Enfermedad de Wolman/genética
5.
J Am Coll Nutr ; 19(4): 472S-477S, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10963467

RESUMEN

OBJECTIVE: To determine effects of conjugated linoleic acid (CLA) on establishment and progression of experimentally-induced atherosclerosis in rabbits. METHODS: For establishment of atherosclerosis, New Zealand White rabbits were fed a semipurified diet containing 0.1% to 0.2% cholesterol for 90 days. Some groups were fed diet and CLA. For effects on progression of atherosclerosis, rabbits with established atherosclerosis were fed a semipurified diet +/- CLA for 90 days. RESULTS: At dietary levels as low as 0.1%, CLA inhibited atherogenesis. At dietary levels of 1%, CLA caused substantial (30%) regression of established atherosclerosis. This is the first example of substantial regression of atherosclerosis being caused by diet alone. CONCLUSION: Dietary CLA is an effective inhibitor of atherogenesis and also causes regression of established atherosclerosis.


Asunto(s)
Arteriosclerosis/tratamiento farmacológico , Grasas Insaturadas en la Dieta/administración & dosificación , Ácido Linoleico/administración & dosificación , Animales , Aorta/patología , Arteriosclerosis/inducido químicamente , Arteriosclerosis/metabolismo , Arteriosclerosis/prevención & control , Grasas Insaturadas en la Dieta/farmacología , Femenino , Ácido Linoleico/farmacología , Lípidos/sangre , Hígado/química , Masculino , Conejos
6.
Biotechnol Bioeng ; 52(6): 696-706, 1996 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-18629948

RESUMEN

We have developed a serum-free cell culture process utilizing a recombinant baculovirus (AcNPV) expression vector to infect Trichoplusia ni insect cells for the production of the human lysosomal enzyme, glucocerebrosidase. The enzyme, which is harvested as a secreted protein in this process, can serve as a replacement therapy for the genetic deficiency Gaucher disease. In the course of pilot scale-up of a batch glucocerebrosidase process from 25-mL working volume shaker flask units to 25-L working volume stirred bioreactor units, a semi-empirical model was developed for the rational determination of scaleable process parameters, including host cell density at infection, multiplicity of infection (MOI), and harvest time. A key assumption of the model is that maximum protein production is limited by the serum-free medium's nutritional capacity, which can, in turn, be determined from the growth of uninfected cells. For the host cell/medium combination used in this study, the nutritional limit was determined to be 1.3 x 10(7) to 1.7 x 10(7) viable-cell-days/mL. Based on this, the model predicts that optimal protein expression is consistent with a 4-day batch process where the host cell density at the time of infection is 1.5 x 10(6) to 2.0 x 10(6) cells/mL and the MOI is 0.09-0.3. These parameters were empirically confirmed to give the highest achievable batch product yield, first in shaker flasks and then at larger scales. The low MOI allows at least one population doubling to take place post viral addition, so that the effective infected cell density producing product generally exceeds 4 x 10(6) cells/mL. It was also interesting to note that this process consistently achieved the same level of maximum protein production at the 25-L bioreactor scale in 4 days compared to 5 days at the shaker flask scale. This may be attributable to better control of the culture environment in the bioreactor. Unlike some other lepidopteran insect cells, such as Sf-9, T. ni cells were found to produce significant levels of the inhibitory metabolites ammonia and lactate. Our results suggest that reduction and/or removal of inhibitory metabolites might be beneficial for infection of high-density cultures of these cells and might also facilitate application of more sophisticated culture strategies, including fed-batch. (c) 1996 John Wiley & Sons, Inc.

7.
Am J Orthod Dentofacial Orthop ; 104(2): 180-7, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8338071

RESUMEN

This research deals with the assessment of the role of the nose, lips, and chin in achieving a balanced facial profile. A survey instrument of constructed androgynous facial silhouettes was evaluated by 545 professionals. The silhouettes had varied nose, lips, and chin relationships, as well as changes in facial angle and angle of convexity. The varied facial profiles were graded on the basis of most preferred to least preferred. The data was computed, and it was found that in males, a straighter profile was preferred in comparison with a slightly convex profile for the females. Among the various unfavorable combinations, the worst ones were either with an extremely recessive chin or those with excessively convex faces. More lip protrusion was found acceptable for both male and female faces when either a large nose or a large chin was present. It is suggested that orthodontic treatment goals should be attuned to the achievement of balanced and harmonious facial features rather than rigid adherence to standard average dental and skeletal parameters. Treatment of adolescent children should also take into account the changes in the thickness of the soft tissue integument at the nose, lips, and chin.


Asunto(s)
Belleza , Estética Dental , Cara/anatomía & histología , Cefalometría , Mentón/anatomía & histología , Femenino , Humanos , Labio/anatomía & histología , Masculino , Nariz/anatomía & histología , Percepción , Estándares de Referencia , Factores Sexuales
8.
Proc Natl Acad Sci U S A ; 87(10): 3700-4, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2140191

RESUMEN

To investigate the function of base 792 of 16S rRNA in 30S ribosomes of Escherichia coli, the wild-type (adenine) residue was changed to guanine, cytosine, or uracil by oligonucleotide-directed mutagenesis. Each base change conferred a unique phenotype on the cells. Cells containing plasmid pKK3535 with G792 or T792 showed no difference in generation time in LB broth containing ampicillin, whereas cells with C792 exhibited a 20% increase in generation time in this medium. To study the effect on cell growth of a homogeneous population of mutant ribosomes, the mutations were cloned into the 16S rRNA gene on pKK3535 carrying a spectinomycin-resistance marker (thymine at position 1192), and the cells were grown with spectinomycin. Cells containing G792 or C792 showed 16% and 56% increases in generation time, respectively, and a concomitant decrease in 35S assimilation into proteins. Cells with T792 did not grow in spectinomycin-containing medium. Maxicell analyses indicated decreasing ability to form 70S ribosomes from 30S subunits containing guanine, cytosine, or uracil at position 792 in 16S rRNA. It appeared that C792-containing 30S ribosomes had lost the ability to bind initiation factor 3.


Asunto(s)
Escherichia coli/genética , ARN Ribosómico 16S/genética , ARN Ribosómico/genética , Ribosomas/metabolismo , Secuencia de Bases , Farmacorresistencia Microbiana/genética , Escherichia coli/crecimiento & desarrollo , Escherichia coli/metabolismo , Genes Bacterianos , Datos de Secuencia Molecular , Mutación , Conformación de Ácido Nucleico , Plásmidos , Espectinomicina/farmacología
9.
Proc Natl Acad Sci U S A ; 84(10): 3107-11, 1987 May.
Artículo en Inglés | MEDLINE | ID: mdl-3106961

RESUMEN

A bovine retinal cDNA clone encoding the complete sequence (354 amino acids) of Go alpha, a guanine nucleotide-binding protein (G protein), was isolated by using oligonucleotide probes complementary to published sequences in two putative clones for the alpha subunit of bovine transducin (T alpha). The deduced amino acid sequence contained sequences identical to those in seven tryptic peptides (total 63 amino acids) from bovine brain Go alpha. The cDNA for bovine retinal Go alpha exhibits greater than 90% identity in both coding and 3' untranslated regions with a recently described partial cDNA clone for Go alpha from rat brain [Itoh, H., Kozasa, T., Nagata, S., Nakamura, S., Katada, T., Ui, M., Iwai, S., Ohtsuka, E., Kawasaki, H., Suzuki, K. & Kaziro, Y. (1986) Proc. Natl. Acad. Sci. USA 83, 3776-3780]. Comparison of the nucleotide and deduced amino acid sequences of the bovine Go alpha clone with those previously reported for other G proteins of bovine origin (Gs alpha, Gi alpha, and T alpha) reveals extensive regions identical to those surrounding the amino acids modified by cholera toxin and pertussis toxin. There are also marked similarities of sequence in regions of the G proteins, elongation factors, and the ras p21 gene products that are believed to be involved in guanine nucleotide binding and GTP hydrolysis.


Asunto(s)
Proteínas de Unión al GTP/genética , Retina/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bovinos , Clonación Molecular , ADN/aislamiento & purificación , Homología de Secuencia de Ácido Nucleico
12.
Atherosclerosis ; 39(2): 169-75, 1981 May.
Artículo en Inglés | MEDLINE | ID: mdl-7195724

RESUMEN

Rabbits were fed a semipurified diet containing 40% sucrose, 25% protein, 15% fiber and 14% tallow. The proteins fed were beef (B), textured vegetable protein (TVP) and casein (C). One diet contained beef-TVP (1 : 1) and in another a soy carbohydrate fraction, spent flakes, was added to the diet; it provided 2.2% protein and 10.5% fiber. TVP provided 6.4% soluble carbohydrate and 10.5% fiber. The diets were fed from 8 months. Diets containing beef protein or casein gave significantly higher serum cholesterol levels and atherosclerosis and significantly lower serum HDL-cholesterol than did the other 3 diets. The beef-TVP (1 : 1) diet gave low serum cholesterol (67% below beef) levels and atherosclerosis (47% below beef). This effect is probably due to the protein. The diet containing spent flakes gave low serum cholesterol levels (44% below beef) and atherosclerosis (45% below beef). This effect is attributed to the different fiber. The lowest serum cholesterol levels and least severe atherosclerosis were observed in the rabbits fed TVP.


Asunto(s)
Arteriosclerosis/etiología , Colesterol/deficiencia , Animales , Peso Corporal , Caseínas/administración & dosificación , Bovinos , Celulosa , Hígado/análisis , Hígado/anatomía & histología , Masculino , Carne , Tamaño de los Órganos , Proteínas de Vegetales Comestibles/administración & dosificación , Conejos , Glycine max
13.
Lipids ; 16(2): 87-92, 1981 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7242272

RESUMEN

Various aspects of lipid metabolism were compared in Fisher 344 (F) and Sprague-Dawley (SD) rats aged 2, 6, 12, 18 and 24 months. The analyses included free and total cholesterol of serum and liver, LCAT, hepatic HMG-CoA reductase, cholesterol 7 alpha-hydroxylase, fatty acid synthetase, acetyl CoA carboxylase and cholesterol synthesis from acetate or mevalonate. The body weight of SD rats increases with age whereas that of F rats plateaus at 9-12 months. Liver and aorta cholesterol levels were comparable for the 2 strains. Serum cholesterol varied but was usually lower in F rats. HMG-CoA reductase and cholesterol 7 alpha-hydroxylase activities were not significantly different. Cholesterol synthesis from acetate was significantly higher only in 2-month-old F rats; synthesis from mevalonate was similar at each level. Acetyl CoA carboxylase and fatty acid synthetase activity were generally higher in F rats at every age level. The major difference between F and SD rats is in their pattern of weight gain with age. Differences in lipid metabolism are most marked between the young (2-month) rats.


Asunto(s)
Colesterol/metabolismo , Metabolismo de los Lípidos , Hígado/metabolismo , Envejecimiento , Animales , Peso Corporal , Colesterol/biosíntesis , Colesterol 7-alfa-Hidroxilasa/metabolismo , Hidroximetilglutaril-CoA Reductasas/metabolismo , Hígado/anatomía & histología , Masculino , Fosfatidilcolina-Esterol O-Aciltransferasa/sangre , Ratas , Especificidad de la Especie
15.
Am J Clin Nutr ; 32(3): 597-600, 1979 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-420151

RESUMEN

Male Wistar rats were fed commercial ration and given whole milk, skim milk, or water to drink. After 3 weeks the control group showed the greatest weight gain. Rats given whole milk had the smallest livers. Serum cholesterol levels were significantly lower in rats fed either whole or skim milk, but other serum lipids were unaffected. Liver triglyceride levels were lowest in the rats on skim milk. Activities of hepatic fatty acid synthetase, hydroxymethyl-glutaryl coenzyme A reductase and cholesterol 7alpha-hydroxylase were similar in the two milk-fed groups and considerably lower than in the controls.


Asunto(s)
Colesterol/metabolismo , Grasas de la Dieta , Leche , Animales , Peso Corporal , Colesterol/sangre , Metabolismo de los Lípidos , Masculino , Ratas
16.
Chest ; 69(3): 384-7, 1976 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-971609

RESUMEN

The correction of shunts resulting from partial anomalous pulmonary venous drainage has become an accepted surgical procedure. Surgical complications, other than those that were purely postoperative, have been rare. The present report details the case histories of three patients with unusual complications resulting from this type of surgery. Unilateral pulmonary venous obstruction and repeated infections occurred in one patient. In another, obstruction of the superior vena cava resulted. In the third patient, an indaequate operation was performed when the site of partial anomalous pulmonary venous drainage into the coronary sinus was not recognized initially at the time of surgery.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/efectos adversos , Venas Pulmonares/anomalías , Adulto , Niño , Femenino , Defectos de los Tabiques Cardíacos/cirugía , Humanos , Masculino , Venas Pulmonares/cirugía
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