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1.
Support Care Cancer ; 23(5): 1459-71, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25711653

RESUMEN

BACKGROUND: Extravasation is a potentially severe complication that can occur during the administration of chemotherapy. The scarcity of evidence available makes it difficult to develop an optimal management scheme. The purpose of this guideline is to review the relevant scientific literature on the prevention, management, and treatment of extravasation occurring during the administration of chemotherapy to cancer patients. METHOD: A scientific literature review was conducted using the PubMed search tool. The period covered was from database inception to April 2014, inclusively. Since the literature on extravasation treatment is often empirical, anecdotal, and controversial, the review also identified clinical practice guidelines and expert consensuses published by relevant international organizations and cancer agencies. RESULTS: Identification of potential risk factors and preventive measures can reduce the risk of extravasation. Recognition and management of symptoms are crucial in patients with this complication. Provision of adequate instruction to personnel responsible for administering chemotherapy and to patients on recognizing symptoms, preventing, and managing extravasation is essential. Extravasation can be treated with dry warm or cold compresses and various antidotes such as dimethyl sulfoxide, dexrazoxane, hyaluronidase, or sodium thiosulfate, depending on the agent that has caused extravasation. Patient monitoring to assess the progression or regression of symptoms and to thus take the appropriate measures is necessary. CONCLUSION: Several strategies must be established to ensure that extravasation is recognized and properly managed. Given the evidence available at this time, the Comité de l'évolution des pratiques en oncologie (CEPO) has made recommendations for clinical practice in Quebec.


Asunto(s)
Antineoplásicos/efectos adversos , Cateterismo Venoso Central/efectos adversos , Cateterismo Periférico/efectos adversos , Extravasación de Materiales Terapéuticos y Diagnósticos/diagnóstico , Extravasación de Materiales Terapéuticos y Diagnósticos/terapia , Neoplasias/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Dexrazoxano/uso terapéutico , Dimetilsulfóxido/uso terapéutico , Extravasación de Materiales Terapéuticos y Diagnósticos/prevención & control , Humanos , Hialuronoglucosaminidasa/uso terapéutico , Quebec , Factores de Riesgo , Tiosulfatos/uso terapéutico
2.
Science ; 245(4925): 1481-4, 1989 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-17776798

RESUMEN

An empirical model describing the diffusion kinetics of oxygen in silicate minerals under hydrothermal conditions has been established for temperatures between 773 and 1073 Kelvin at 100 megapascals of water pressure. The equation, log D = alpha + (beta/T) + [(gamma + (delta/T))Z], where D is the diffusion coefficient, alpha, beta, gamma, and delta are constants, T is the Kelvin temperature, and Z is the total ionic porosity, may be used to predict diffusion coefficients, in most cases to within the reported experimental reproducibility of a factor of 2. For oxygen diffusion, alpha = -2, beta = -3.4 x 10(4)K, gamma = -0.13, and delta = 6.4 x 10(2)K, for D in square centimeters per second. Limited data for the diffusion of argon in silicates suggest that the model describes this system as well.

3.
Endocrinology ; 137(6): 2558-64, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8641209

RESUMEN

We have described a thyroid hormone receptor in synaptosomes of the chick embryo brain. To understand how the hormones exert their actions at this level, we performed a series of studies to demonstrate that this receptor could be linked to G proteins. Guanosine 5'-[gamma-thio]triphosphate (GTP gamma S)(100 muM) lowered the binding capacity of the receptor high affinity site from 8.9 +/- 1.3 to 3.4 +/- 1.3 ng T3/mg protein, a finding consistent with the coupling of receptor to G proteins. Furthermore, ADP ribosylation with pertussis toxin showed that thyroid hormones induced a dose-dependent increase in the inactive alpha 0-subunit of the G0 protein. This effect was detected at 10 pM, with a maximal increase (mean +/- SEM, 50 +/- 3.6%) at 100 nM, and T4 was as effective as T3. Both hormones also decreased the intrinsic guanine triphosphatase activity of G proteins by lowering the binding of GTP to the alpha-subunit and their rate of hydrolysis. This inhibition was greater with T4 (25 +/- 5%) than with T3 (14 +/- 2%), suggesting that the former could be the more active hormone at the synaptosomal level. The effect on guanine triphosphatase activity confirms that the synaptosomal thyroid hormone receptor is coupled to a G(zero) protein. These results demonstrate that thyroid hormones increase or favor the ADP ribosylation of G alpha(zero) by pertussis toxin. Thus, they enhance the alpha(zero)-GDP form of the G(zero) protein, namely its inactive conformation. By decreasing the activity of this protein, these hormones may modulate the formation of second messengers in synaptosomes and intervene in the regulation of neuronal proliferation and differentiation induced by several factors. Therefore, thyroid hormones may exert their action on brain maturation at least in part by modulating G alpha(zero) through their synaptosomal receptor.


Asunto(s)
Encéfalo/embriología , Proteínas de Unión al GTP/metabolismo , Receptores de Hormona Tiroidea/metabolismo , Sinaptosomas/metabolismo , Tiroxina/farmacología , Triyodotironina/farmacología , Adenosina Difosfato Ribosa/metabolismo , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Embrión de Pollo , GTP Fosfohidrolasas/metabolismo , Guanosina 5'-O-(3-Tiotrifosfato)/farmacología , Toxina del Pertussis , Sinaptosomas/efectos de los fármacos , Tiroxina/metabolismo , Triyodotironina/metabolismo , Factores de Virulencia de Bordetella/farmacología
4.
J Thorac Cardiovasc Surg ; 128(1): 109-16, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15224029

RESUMEN

OBJECTIVE: Cardiopulmonary bypass triggers a systemic inflammatory response that alters pulmonary endothelial function, which can contribute to pulmonary hypertension. This study was designed to demonstrate that inhaled prostacyclin, a selective pulmonary vasodilator prostaglandin, prevents pulmonary arterial endothelial dysfunction induced by cardiopulmonary bypass. METHODS: Three groups of Landrace swine were compared: control without cardiopulmonary bypass (control group); 90 minutes of normothermic cardiopulmonary bypass (bypass group); 90 minutes of cardiopulmonary bypass and treated with prostacyclin during cardiopulmonary bypass (continuous nebulization with continuous positive airway pressure until the end of the cardiopulmonary bypass; prostacyclin group). After 60 minutes of reperfusion, swine were put to death and pulmonary arteries harvested. After contraction to phenylephrine, endothelium-dependent relaxation to bradykinin and acetylcholine was studied in standard organ chamber experiments. The pulmonary artery intravascular cyclic adenosine monophosphate content was compared between the 3 groups (post-cardiopulmonary bypass). RESULTS: There was a statistically significant improvement of the endothelium-dependent relaxation to bradykinin in the prostacyclin group when compared with the bypass group (P <.05). There was no statistically significant difference for endothelium-dependent relaxation to acetylcholine (P >.05) between the prostacyclin and the bypass groups. There was a statistically significant decrease in the cyclic adenosine monophosphate content and a statistically significant increase of the mean pulmonary artery pressure in the bypass group only (P <.05). CONCLUSION: Prophylactic use of inhaled prostacyclin has a favorable impact on the pulmonary endothelial dysfunction induced by cardiopulmonary bypass associated with preservation of pulmonary intravascular cyclic adenosine monophosphate content and the pulmonary vascular tone.


Asunto(s)
Adenosina Monofosfato/metabolismo , Antihipertensivos/administración & dosificación , Puente Cardiopulmonar/efectos adversos , AMP Cíclico/sangre , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/fisiopatología , Epoprostenol/administración & dosificación , Enfermedades Pulmonares/etiología , Enfermedades Pulmonares/prevención & control , Pulmón/irrigación sanguínea , Pulmón/metabolismo , Acetilcolina/administración & dosificación , Administración por Inhalación , Animales , Antioxidantes/metabolismo , Biomarcadores/sangre , Fármacos Cardiovasculares/administración & dosificación , Modelos Animales de Enfermedad , Endotelio Vascular/metabolismo , Femenino , Indoles/administración & dosificación , Enfermedades Pulmonares/metabolismo , Enfermedades Pulmonares/fisiopatología , Masculino , Modelos Cardiovasculares , Fenilefrina/administración & dosificación , Arteria Pulmonar/efectos de los fármacos , Arteria Pulmonar/metabolismo , Arteria Pulmonar/fisiopatología , Presión Esfenoidal Pulmonar/efectos de los fármacos , Porcinos , Resistencia Vascular/efectos de los fármacos , Vasoconstrictores/administración & dosificación , Vasodilatación/efectos de los fármacos , Vasodilatadores/administración & dosificación
5.
Acta Crystallogr A ; 45 ( Pt 3): 247-54, 1989 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-2619967

RESUMEN

By characterizing isomorphism in reciprocal space [i.e. diffraction data sets are isomorphous if they have the same geometry (the same reciprocal-lattice unit cell) and the same symmetry] it is shown that the diffraction data of a native protein and of its heavy-atom derivatives, the calculated data of a partial structure and the observed data of its associated complete structure, and the Friedel-pair data of an anomalously scattering crystal structure all belong to the more general class of isomorphous data sets. Their joint probability distributions for two- and three-phase structure invariants are shown to be isomorphous: they have the same functional form and differ only in individual atomic scattering factors. General joint probability distributions, which can be used for any isomorphous data pairs, are presented.


Asunto(s)
Cristalografía , Modelos Estadísticos , Estructura Molecular , Proteínas
6.
Acta Neurol Belg ; 84(3): 105-11, 1984.
Artículo en Francés | MEDLINE | ID: mdl-6464661

RESUMEN

A paravertebral ganglioneuroma was discovered in a 25 year-old woman presenting a transverse spinal syndrome at the same level. Exeresis necessitated sacrifice of the ninth left intercostal artery, but paraplegia regressed completely under corticotherapy. Additional exploration and subsequent clinical evolution revealed multiple sclerosis, of which the pavaplegia had been a manifestation. The authors discuss ganglioneuroma in the adult, a rare tumour, and the possibility of a link with multiple sclerosis. The association seems fortuitous despite the fact that the tumour and the transverse myelitis occurred at the same level.


Asunto(s)
Ganglioneuroma/complicaciones , Esclerosis Múltiple/complicaciones , Paraplejía/etiología , Neoplasias del Sistema Nervioso Periférico/complicaciones , Sistema Nervioso Simpático , Corticoesteroides/uso terapéutico , Adulto , Femenino , Ganglioneuroma/patología , Humanos , Esclerosis Múltiple/tratamiento farmacológico , Neoplasias del Sistema Nervioso Periférico/patología
7.
Ann Cardiol Angeiol (Paris) ; 50(6): 312-5, 2001 Oct.
Artículo en Francés | MEDLINE | ID: mdl-12555621

RESUMEN

The chronic constrictive pericarditis is a rare affection, with multiple etiologies and concerning especially the adult. We report a case of chronic constrictive pericarditis in an African child in whom no etiology was found. A review of the literature raises the characteristics of chronic constrictive pericarditis for a better therapeutic management.


Asunto(s)
Pericarditis Constrictiva/diagnóstico , África Oriental , Niño , Enfermedad Crónica , Humanos , Masculino
8.
J Chir (Paris) ; 139(4): 232-5, 2002 Sep.
Artículo en Francés | MEDLINE | ID: mdl-12410142

RESUMEN

Extracorporeal circulation (ECC) is not only used for open heart surgery. There are also other surgical and medical applications. ECC can be used for encephalic arteries surgery to induce hypothermia and maximally protect the brain. Femoro-femoral ECC may be needful for urgent traumatologic surgery of the supra-aortic trunci. Intracranial aneurysm repair can occasionally necessitate deep hypothermia and circulatory arrest with ECC. Renal cell carcinomas may metastasize to the right atrium and surgery with ECC is mandatory for complete excision. Some reports in the literature mention use of ECC for hepatic surgery of intra-hepatic aneurysms. With acute peripheral ischemia, metabolites in the affected limb can be washed out with good results. Medical indications for ECC are numerous with pulmonary assistance as one of the foremost when mechanical ventilation failed. Homogeneous and rapid rewarming of hypothermic patients can be achieved with ECC. Finally, some groups have reported the use of ECC to administer chemotherapy in limb melanoma.


Asunto(s)
Circulación Extracorporea/métodos , Procedimientos Quirúrgicos Cardíacos , Circulación Extracorporea/instrumentación , Humanos , Enfermedades Renales/cirugía , Hepatopatías/cirugía , Oncología Médica , Procedimientos Neuroquirúrgicos , Selección de Paciente , Recalentamiento , Procedimientos Quirúrgicos Torácicos , Procedimientos Quirúrgicos Vasculares
14.
Phys Rev Lett ; 101(21): 212503, 2008 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-19113406

RESUMEN

Coulomb excitation of the exotic neutron-rich nucleus (26)Ne on a (208)Pb target was measured at 58 MeV/u in order to search for low-lying E1 strength above the neutron emission threshold. This radioactive beam experiment was carried out at the RIKEN Accelerator Research Facility. Using the invariant mass method in the 25Ne+n channel, we observe a sizable amount of E1 strength between 6 and 10 MeV excitation energy. By performing a multipole decomposition of the differential cross section, a reduced dipole transition probability of B(E1)=0.49+/-0.16e(2) fm(2) is deduced, corresponding to 4.9+/-1.6% of the Thomas-Reiche-Kuhn sum rule. For the first time, the decay pattern of low-lying strength in a neutron-rich nucleus is measured. The extracted decay pattern is not consistent with several mean-field theory descriptions of the pygmy states.

15.
Phys Rev Lett ; 97(9): 092501, 2006 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-17026356

RESUMEN

The N = 28 shell closure has been investigated via the 46Ar(d,p)47Ar transfer reaction in inverse kinematics. Energies and spectroscopic factors of the neutron p(3/2), p(1/2), and f(5/2) states in 47Ar were determined and compared to those of the 49Ca isotone. We deduced a reduction of the N = 28 gap by 330(90) keV and spin-orbit weakenings of approximately 10(2) and 45(10)% for the f and p states, respectively. Such large variations for the f and p spin-orbit splittings could be accounted for by the proton-neutron tensor force and by the density dependence of the spin-orbit interaction, respectively. This contrasts with the picture of the spin-orbit interaction as a surface term only.

16.
Artículo en Inglés | MEDLINE | ID: mdl-7584324

RESUMEN

There are several dimensions and levels of complexity in which information on protein motifs may be available. For example, one-dimensional sequence motifs may be associated with secondary structure identifiers. Alternatively, three-dimensional information on polypeptide segments may be used to induce prototypical three-dimensional structure templates. This paper surveys various representations encountered in the protein motif discovery literature. Many of the representations are based on incompatible semantics, making difficult the comparison and combination of previous results. To make better use of machine learning techniques and to provide for an integrated knowledge representation framework, a general representation language--in which all types of motifs can be encoded and given a uniform semantics--is required. In this paper we propose such a model, called a spatial description logic, and present a machine learning approach based on the model.


Asunto(s)
Inteligencia Artificial , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Análisis de Secuencia/métodos , Aminoácidos/química , Lógica , Modelos Teóricos , Lenguajes de Programación , Programas Informáticos
17.
Artículo en Inglés | MEDLINE | ID: mdl-7584423

RESUMEN

A new category of protein motif is introduced. This type of motif captures, in addition to global structure, the nested structure of its component parts. A dataset of four proteins is represented using this scheme. A structured machine discovery procedure is used to discover recurrent amino acid motifs and this knowledge is utilized for the expression of subsequent protein motif discoveries. Examples of discovered multilevel motifs are presented.


Asunto(s)
Sistemas de Información , Proteínas/química , Animales , Simulación por Computador , Bases de Datos Factuales , Humanos , Conformación Proteica , Análisis de Secuencia
18.
Mol Cell Biol Res Commun ; 1(2): 132-9, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10356362

RESUMEN

A pool of MAPK was found in hepatic plasma membrane (PM) and endosomes (ENs). After injection of a single dose of EGF (10 microg/100 g body weight), MAPK was detected in EGF receptor (EGFR) immunoprecipitates prepared from ENs. MAPK was detected in a time-dependent manner in EGFR immunoprecipitates that was coincident with the progressive concentration of the EGFR. The EGFR-associated MAPK was also detected by using an anti-phospho-MAPK suggesting that it was active. MAPK was present in wheat-germ agglutinin (WGA) eluates prepared from ENs and was maximally tyrosine-phosphorylated at the time peak of EGFR internalization. MAPK therefore is compartmentalized in PM and ENs of rat liver. A fraction of the endosomal MAPK was found to be associated with the internalized EGFR complexes, suggesting that it plays a role in the control of the EGFR activity at this locus.


Asunto(s)
Endosomas/metabolismo , Receptores ErbB/metabolismo , Hígado/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Animales , Compartimento Celular , Membrana Celular/metabolismo , Endosomas/enzimología , Femenino , Immunoblotting , Hígado/enzimología , Hígado/ultraestructura , Fosforilación , Pruebas de Precipitina , Ratas , Ratas Sprague-Dawley , Tirosina/metabolismo , Aglutininas del Germen de Trigo
19.
Biol Neonate ; 45(1): 41-8, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6318840

RESUMEN

In this study we have examined the effect of neonatal hypothyroidism and triiodothyronine (T3) replacement therapy on the maximal binding capacity (MBC) and the affinity of T3 receptors prepared from liver, brain and lungs. Rats were radiothyroidectomized at birth and administered T3 or its placebo starting at 8 days of age. The thyroid state in normal, hypothyroid and hypothyroid T3-treated rats was assessed by serum determination of thyroxine, T3 and by the measurement of the hepatic alpha-glycerophosphate dehydrogenase. The animals were sacrificed at 8, 16 or 24 days of age and the T3 binding was estimated in isolated nuclei and in salt nuclear extracts. The MBC of the T3 receptors was higher in the hypothyroid rats at all ages when it was determined in isolated nuclei, but not when was measured in nuclear extracts. At 8 days, the MBC had risen twofold or more in the receptors from brain (1.0 +/- 0.37 vs. 0.4 +/- 0.1 ng T3/mg DNA in controls) and from lungs (0.6 +/- 0.25 vs. 0.3 +/- 0.15 ng T3/mg DNA in controls), but was only slightly elevated in the hepatic receptor (0.62 +/- 0.08 vs. 0.48 +/- 0.15 ng T3/mg DNA in controls). At 16-24 days, the highest value of MBC was observed in the hepatic receptor (0.83 +/- 0.04 vs. 0.41 +/- 0.1 ng T3/mg DNA in controls) followed by the brain receptor (0.65 +/- 0.03 vs. 0.35 +/- 0.02 ng T3/mg DNA in controls), and that of lung (0.39 +/- 0.07 vs. 0.20 +/- 0.03 ng T3/mg DNA in controls).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Química Encefálica , Hipotiroidismo/tratamiento farmacológico , Hígado/análisis , Pulmón/análisis , Receptores de Superficie Celular/metabolismo , Triyodotironina/metabolismo , Animales , Femenino , Humanos , Hipotiroidismo/inducido químicamente , Hipotiroidismo/metabolismo , Embarazo , Ratas , Ratas Endogámicas , Receptores de Hormona Tiroidea , Triyodotironina/uso terapéutico
20.
Acta Crystallogr D Biol Crystallogr ; 50(Pt 2): 155-66, 1994 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-15299453

RESUMEN

Methods to assist in the spatial and visual analysis of electron-density maps have been investigated as part of a project in molecular scene analysis [Fortier, Castleden, Glasgow, Conklin, Walmsley, Leherte & Allen (1993). Acta Cryst. D49, 168-178]. In particular, the usefulness of the topological approach for the segmentation of medium-resolution (3 A) maps of proteins and their interpretation in terms of structural motifs has been assessed. The approach followed is that proposed by Johnson [Johnson (1977). ORCRIT. The Oak Ridge Critical Point Network Program. Chemistry Division, Oak Ridge National Laboratory, USA] which provides a global representation of the electron-density distribution through the location, identification and linkage of its critical points. In the first part of the study, the topological approach was applied to calculated maps of three proteins of small to medium size so as to develop a methodology that could then be used for analyzing maps of medium resolution. The methodology was then applied to both calculated and experimental maps of penicillopepsin at 3 A resolution. The study shows that the networks of critical points can provide a useful segmentation of the maps, tracing the protein main chains and capturing their conformation. In addition, these networks can be parsed in terms of secondary-structure motifs, through a geometrical analysis of the critical points. The procedure adopted for secondary-structure recognition, which was phrased in terms of geometry-based rules, provides a basis for a further automated implementation of a more complete set of recognition operations through the use of artificial-intelligence techniques.

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