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1.
MedUNAB ; 11(2): 185-190, abr.-jul. 2008. ilus
Article in Spanish | LILACS | ID: biblio-834850

ABSTRACT

La deficiencia de factor XIII de la coagulación es un trastorno raro de la coagulación, entre los que están la afibrinogenemis y los de factor II, V, V+VIII, VII, X y XI. Estos son son anormalidades de la hemostasia con herencia autosómica recesiva; su prevalencia es de 1 en 500,000 a 2 millones de personas. Por su rareza, tipo y severidad de las hemorragias y lo poco claro que es el defecto molecular y su manejo son un reto diagnóstico y terapéutico. Para algunas de estas deficiencias no existen concentrados del factor de coagulación implicado disponibles, por lo que es necesario utilizar derivados sanguíneos o medicamentos hemostáticos alternativos, lo que puede generar complicaciones, en ocasiones fatales; estas complicaciones pueden ser minimizadas evaluando en cada caso el riesgo de sangrado o de trombosis seleccionando como tratamiento alternativas diferentes a los derivados de la sangre, o incluso no administrando tratamiento en los episodios hemorrágicos leves. En este artículo se describe el caso de una paciente con diagnóstico de déficit de factor XIII que debutó con hematuria y complicaciones ginecoobstétricas; hay historia familiar de consanguinidad y de déficit de factor XIII; recibió manejo con crioprecipitados y antifibrinolíticos y profilaxis con crioprecipitados durante el transcurso de su segundo embarazo, lográndose un producto a término con un parto por cesárea sin complicaciones hemorrágicas o trombóticas.


The factor XIII deficiency is a rare clotting disorder, among which are afibrinogenemia and factor II, V, V+VIII, VII, X and XI ones. These are hemostasis anomalies with autosomal recessive herency; its prevalence is 1 in 500,000 to 2 million people. For its rarity, type and bleeding severity, and its unclear molecular defect, this is a challenge diagnostic and therapeutic effort. The are not clotting factor concentrates available, reason what it is necessary to use blood derivatives or alternative hemostatic agents, which can generate complications, sometimes fatal; these complications can be minimized assessing in each case its bleeding or thrombosis riks to select alternatives to blood or not to do treatment in mild bleeding episodes. This paper describes a case of a women diagnosed with XIII deficiency that began with hematuria and gynocobstetric complications; she received plasma concentrates and antifibrinolytic agents, plus prophylaxis with these products in her second pregnancy, achieving a at term product by caesarean section without any complications.


Subject(s)
Blood Coagulation Disorders , Factor XIII , Hemorrhage , Hemostasis
2.
MedUNAB ; 11(3): 218-224, 2008.
Article in Spanish | LILACS | ID: biblio-1007090

ABSTRACT

Una relación entre la hemofilia y la osteoporosis ha sido sugerida, lo cual ha conducido a la iniciativa de realizar tanto revisiones como estudios acerca de este tema. Las hemofilias son un trastorno de la coagulación hereditario, causado por deficiencia o defecto en la actividad coagulante de los factores VIII (hemofilia A) y IX (hemofilia B). La hemartrosis o hemorragia dentro de las articulaciones representa entre el 65-80% de todas las hemorragias en hemofílicos y determinan en gran parte el deterioro en la calidad de vida por su curso crónico e incapacitante. La osteoporosis es una enfermedad esquelética sistémica caracterizada por compromiso de la resistencia ósea que aumenta el riesgo de fractura. La hemofilia y la osteoporosis tienen varios aspectos en común: ambas enfermedades están acompañadas de dolor crónico, invalidez, pérdida de la independencia, aumento de la mortalidad y tienen un impacto negativo sobre la calidad de vida de los pacientes. La osteoporosis es la enfermedad metabólica ósea más frecuente en la población mayor, con alcances socioeconómicos importantes. No obstante, las hemofilias son menos comunes, pero los costos de su tratamiento global son más elevados. Aparte de estas obvias similitudes entre la hemofilia y la osteoporosis, se considera que hay una fuerte relación entre estas dos entidades más que la que se suponía antes, y los pacientes con hemofilia severa y artropatía hemofílica tienen mayor riesgo de tener un pico de masa ósea bajo. La hemofilia está asociada a varios factores que predicen un pico de masa ósea bajo y, ciertos de estos factores, también pueden predecir un aumento en la pérdida de la masa ósea; sin embargo, aún no se ha demostrado que la pérdida ósea sea mayor en hemofílicos más que en los controles sanos, ni el grado en el cual el pico de masa ósea baja confiere un aumento en el riesgo de fractura. Se necesitan estudios prospectivos antes de establecer guías acerca de la prevención o tratamiento de la osteoporosis en hemofílicos, las cuales no pueden solamente basarse en el resultado de la densitometría ósea (DMO) aislada. [Sossa CL, Solano MH, Wandurraga EA, Jiménez SI, Galvis HD, Pérez CA. Hemofilia y osteoporosis. MedUNAB 2008; 11:218-224]


A relationship between haemophilia and osteoporosis has been suggested. This association has driven an initiative to do literature reviews and clinical trials. Haemophilia is a disease characterized by inherited coagulation disorders caused by factor VIII (haemophilia A) and factor IX (haemophilia B) defect or deficiency. Haemarthrosis or bleeding inside the articulation represents between 65 and 80% of all bleeding episodes in haempohilics and cause a decrease in the quality of life because of the chronic and incapacitating properties. Osteoporosis is a bone disease characterized by a progressive decrease in bone quality and increase in the fracture risk. Haemophilia and osteoporosis have various common features; both diseases are associated with chronic pain, disability, lost of independency, increase in mortality and a negative impact in the quality of life. Osteoporosis is a bone metabolic disease more often presented in the elder population with a high socioeconomic burden. Even that haemophilia is a less frequent disease than osteoporosis the cost of treatment is more expensive than osteoporosis. It has been described that patients with severe haemophilia and haemophilic arthropathy are at risk of a low bone mass peak; however currently there has not been confirmed by clinical trials that haemophilic patients have a higher risk of fractures and decreased bone mass than healthy controls, and more prospective trials are needed before conclusions to develop clinical guidelines. [Sossa CL, Solano MH, Wandurraga EA, Jiménez SI, Galvis HD, Pérez CA. Haemophilia and osteoporosis. MedUNAB 2008; 11:218-224].


Subject(s)
Hemophilia A , Osteoporosis , Blood Coagulation , Bone Diseases, Metabolic , Factor VIII
3.
Article in English | MEDLINE | ID: mdl-17055342

ABSTRACT

Arsenic, applied as sodium arsenite (As(III)) to either inner or outer surfaces of the isolated toad skin, dose-dependently decreased the short-circuit current (Isc), potential difference (PD) and sodium conductance (G(Na)) in the concentration range 1-1000 microM, with effects often lasting over 3 h. Maximal inhibitory effect was over 90% with an IC(50) of about 34 microM. Applied during amiloride block, As(III) did not change this effect. However, an increase in electric parameters was noted during the initial 30 min in 22 experiments, indicating a possible translocation of cytosolic protein kinase C (PKC) to the membrane within 15 min, thus stimulating sodium transport; this is followed by a progressive inhibition of kinase activity. Comparative effects of amiloride (8 microM), As(III) (100 microM, outer surface) and noradrenaline (NA, 10 microM, inner surface) showed a significant increase in the stimulatory effect of NA on the electric parameters, which could be the result of arsenite clustering of cell surface receptors and activation of ensuing cellular signal transduction pathways. Ouabain 5 microM, followed by As(III) 100 microM, also stimulated the skin response to NA (10 microM), although the duration of the two phases of the response was markedly shortened. The exact mechanism is still in doubt: however, As(III) increases cerebral metabolites of NA and ouabain can increase NA efflux from tissue slices. The amiloride test, performed with As(III) in the outer surface, confirmed significant decrease in all the parameters: the driving force (E(Na)), sodium conductance (G(Na)), and importantly, shunt conductance (G(sh)), due to the known fact that arsenic inhibits gap junctional intercellular communication.


Subject(s)
Anura/physiology , Arsenites/toxicity , Environmental Pollutants/toxicity , Skin/drug effects , Skin/metabolism , Sodium Compounds/toxicity , Sodium/metabolism , Administration, Cutaneous , Amiloride/pharmacology , Animals , Biological Transport/drug effects , Cytosol/drug effects , Cytosol/enzymology , Dose-Response Relationship, Drug , Drug Combinations , Female , Ion Transport/drug effects , Male , Membrane Potentials/drug effects , Norepinephrine/pharmacology , Ouabain/pharmacology , Patch-Clamp Techniques/methods , Protein Kinase C/metabolism , Sodium Channel Blockers/pharmacology
4.
Toxicol In Vitro ; 20(6): 891-8, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16542818

ABSTRACT

The present work investigates the effects of the antiepileptic drug carbamazepine (CBZ) on sodium transport in the isolated skin of the toad Pleurodema thaul. A submaximal concentration of the drug (0.2 mM) applied to the outer surface of the epithelium increased the electrical parameters short-circuit current (Isc) and potential difference (PD) by over 28%, whereas only a higher concentration (1 mM) induced over a 45% decrease in these parameters when applied to the inner surface. The amiloride test showed that the outer surface stimulatory effect was accompanied by an increase and the inner surface inhibitory effect by a decrease in the sodium electromotive force (ENa). Exploration of these effects of CBZ on the outer surface showed that 0.2 mM increased net Na+ (22Na) influx by 20% and 0.6 mM CBZ decreased Na+ mucosa-serosa flux by 19%, a result in agreement with the finding that higher concentrations of CBZ applied to the inner surface not only decreased ENa but also sodium conductance (GNa).


Subject(s)
Anticonvulsants/toxicity , Carbamazepine/toxicity , Sodium/metabolism , Amiloride/pharmacology , Animals , Bufonidae , Dose-Response Relationship, Drug , Female , Ion Transport/drug effects , Male , Skin/drug effects , Skin/metabolism
5.
Article in English | MEDLINE | ID: mdl-16314149

ABSTRACT

The effects of phenytoin on isolated Pleurodema thaul toad skin were investigated. Low (micromolar) concentrations of the antiepileptic agent applied to the outside surface of the toad epithelium increased the electrical parameters (short-circuit current and potential difference) by over 40%, reflecting stimulation of Na(+) transport, whereas higher (millimolar concentrations, outside and inside surface) decreased both electric parameters, the effect being greater at the inside surface (40% and 80% decrease, respectively). The amiloride test showed that the stimulatory effect was accompanied by an increase and the inhibitory effect by a decrease in the sodium electromotive force (ENa). It is concluded that the drug interaction with membrane lipid bilayers might result in a distortion of the lipid-protein interface contributing to disturbance of Na(+) epithelial channel activity. After applying the Na(+)-K(+)-ATPase blocker ouabain and replacing the Na(+) ions in the outer Ringer's solution by choline, it was concluded that both active and passive transport are involved in sodium absorption, although active transport predominates.


Subject(s)
Anticonvulsants/pharmacology , Bufonidae/physiology , Epithelium/drug effects , Phenytoin/pharmacology , Sodium/metabolism , Animals , Choline/pharmacology , Electrophysiology , Enzyme Inhibitors/pharmacology , Epithelium/metabolism , Epithelium/physiology , In Vitro Techniques , Ion Transport/drug effects , Ouabain/pharmacology , Sodium-Potassium-Exchanging ATPase/antagonists & inhibitors
6.
Biophys Chem ; 116(3): 227-35, 2005 Aug 01.
Article in English | MEDLINE | ID: mdl-15894419

ABSTRACT

The interaction of the local anesthetic procaine with human erythrocytes, isolated unsealed human erythrocyte membranes (IUM), isolated toad skins, and molecular models is described. The latter consisted of phospholipid multilayers built-up of dimyristoylphosphatidylcholine (DMPC) and of dimyristoylphosphatidylethanolamine (DMPE), representatives of phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. Optical and scanning electron microscopy of human erythrocytes revealed that procaine induced the formation of stomatocytes. Experiments performed on IUM at 37 degrees C by fluorescence spectroscopy showed that procaine interacted with the phospholipid bilayer polar groups but not with the hydrophobic acyl chains. X-ray diffraction indicated that procaine perturbed DMPC structure to a higher extent when compared with DMPE, its polar head region being more affected. Electrophysiological measurements disclosed a significant decrease in the potential difference (PD) and in the short-circuit current (Isc) after the application of procaine to isolated toad skin, reflecting inhibition of active ion transport.


Subject(s)
Anesthetics, Local/pharmacology , Cell Membrane/drug effects , Erythrocytes/drug effects , Procaine/pharmacology , Skin/drug effects , Skin/metabolism , Sodium/metabolism , Animals , Anura , Cell Membrane/chemistry , Dimyristoylphosphatidylcholine/chemistry , Electrophysiology , Erythrocytes/ultrastructure , Female , Humans , Ion Transport/drug effects , Male , Membranes, Artificial , Microscopy, Electron, Scanning , Molecular Structure , Phosphatidylethanolamines/chemistry , Spectrometry, Fluorescence , X-Ray Diffraction
7.
Biophys Chem ; 109(1): 189-99, 2004 Apr 01.
Article in English | MEDLINE | ID: mdl-15059670

ABSTRACT

The interaction of the local anesthetic benzocaine with the human erythrocyte membrane and molecular models is described. The latter consisted of isolated unsealed human erythrocyte membranes (IUM), large unilamellar vesicles (LUV) of dimyristoylphospatidylcholine (DMPC), and phospholipid multilayers of DMPC and dimyristoylphospatidyletanolamine (DMPE), representatives of phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. Optical and scanning electron microscopy of human erythrocytes revealed that benzocaine induced the formation of echinocytes. Experiments performed on IUM and DMPC LUV by fluorescence spectroscopy showed that benzocaine interacted with the phospholipid bilayer polar groups and hydrophobic acyl chains. X-ray diffraction analysis of DMPC confirmed these results and showed that benzocaine had no effects on DMPE. The effect on sodium transport was also studied using the isolated toad skin. Electrophysiological measurements indicated a significant decrease in the potential difference (PD) and in the short-circuit current (Isc) after the application of benzocaine, reflecting inhibition of active ion transport.


Subject(s)
Anesthetics, Local/pharmacology , Benzocaine/pharmacology , Erythrocyte Membrane/drug effects , Models, Molecular , Anesthetics, Local/chemistry , Anesthetics, Local/metabolism , Animals , Anura , Benzocaine/chemistry , Benzocaine/metabolism , Electrophysiology , Erythrocyte Membrane/metabolism , Humans , Microscopy, Electron, Scanning , Microscopy, Phase-Contrast , Molecular Structure , Skin Physiological Phenomena , X-Ray Diffraction
8.
Biometals ; 17(6): 655-68, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15689109

ABSTRACT

The effects induced by lead ions on the short-circuit current (SCC) and on the potential difference (V) of the toad Pleurodema thaul skin were investigated. Pb2+ applied to the outer (mucosal) surface increased SCC and V and when applied to the inner (serosal) surface decreased both parameters. The stimulatory effect, but not the inhibitory action, was reversible after washout of the metal ion. The amiloride test showed that the increase was due principally to stimulation of the driving potential for Na+ (V-E(Na+)) and that inhibition was accompanied by a reduction in the V-E(Na+) and also by a significant decrease in skin resistance indicating possible disruption of membrane and/or cell integrity. The effect of noradrenaline was increased by outer and decreased by inner administration of Pb2+. The results suggest that mucosal Pb2+ activates toad skin ion transport by stimulating the V-E(Na+) and that serosal Pb2+, with easier access to membrane and cellular constituents, inactivates this mechanism, revealing greater toxicity when applied to the inner surface of the skin.


Subject(s)
Anura/physiology , Iron/pharmacology , Skin Physiological Phenomena , Skin/drug effects , Sodium/metabolism , Amiloride/pharmacology , Animals , Anura/metabolism , Biological Transport , Electrophysiology , Ions , Iron/metabolism , Kinetics , Membrane Potentials , Norepinephrine/pharmacology , Skin/metabolism , Time Factors
9.
Brain Res ; 985(1): 89-97, 2003 Sep 19.
Article in English | MEDLINE | ID: mdl-12957371

ABSTRACT

Reactive gliosis, the cellular manifestation of neuroinflammation, is a pathological hallmark of neurodegenerative diseases including Parkinson's disease. The persistent gliosis observed in the Parkinson's disease substantia nigra (SN) and in humans and animals exposed to the neurotoxicant 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) may represent a chronic inflammatory response that contributes to pathology. We have previously shown that in the absence of interleukin-6 (IL-6) dopaminergic neurons are more vulnerable to MPTP. Since IL-6 is both an autocrine and paracrine proliferation factor for CNS glia, we investigated reactive gliosis in MPTP-lesioned IL-6 (-/-) mice. While astrogliosis was similar in injured IL-6 (+/+) and IL-6 (-/-) SN pars compacta (pc), microgliosis was severely compromised in IL-6 (-/-) mice. In the absence of IL-6, an acute reactive microgliosis was transient with a complete absence of reactive microglia at day 7 post-lesion. Extensive reactive microgliosis was observed in the SNpc of MPTP-lesioned IL-6 (+/+) mice. Because glial derived inducible nitric oxide synthase (iNOS) has been implicated in dopaminergic cell death, we examined glial iNOS expression in the IL-6 genotypes to determine if it correlated with the greater vulnerability and reduced microgliosis observed in the MPTP-lesioned IL-6 (-/-) nigrostriatal system. Both reactive microglia and astrocytes expressed iNOS in the lesioned SNpc. In the IL-6 (-/-) mice, microglial iNOS expression diminished as reactive microgliosis declined. The data suggest IL-6 regulation of microglia activation, while iNOS expression appears to be secondary to cell activation.


Subject(s)
Gliosis/pathology , Interleukin-6/deficiency , Parkinsonian Disorders/pathology , Substantia Nigra/pathology , Animals , Astrocytes/metabolism , Astrocytes/pathology , Gliosis/genetics , Immunohistochemistry , Interleukin-6/genetics , Male , Mice , Mice, Knockout , Microglia/metabolism , Microglia/pathology , Models, Animal , Nitric Oxide Synthase/biosynthesis , Nitric Oxide Synthase Type II , Parkinsonian Disorders/genetics , Substantia Nigra/metabolism
10.
Blood Cells Mol Dis ; 29(1): 14-23, 2002.
Article in English | MEDLINE | ID: mdl-12482399

ABSTRACT

The interaction of the local anesthetic bupivacaine with the human erythrocyte membrane and molecular models is described. The latter consisted of isolated unsealed human erythrocyte membranes (IUM), large unilamellar vesicles (LUV) of dimyristoylphosphatidylcholine (DMPC), and phospholipid multilayers built-up of DMPC and dimyristoylphosphatidylethanolamine (DMPE), representatives of phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. Optical and scanning electron microscopy revealed that bupivacaine induced erythrocyte spheroechinocytosis. According to the bilayer couple hypothesis, this result implied that bupivacaine inserted in the outer monolayer of the erythrocyte membrane. Experiments performed on IUM and DMPC LUV by fluorescence spectroscopy and X-ray diffraction on DMPC and DMPE multilayers confirmed this result. Changes in the molecular organization of membranes alter lipid-protein interactions and induce functional perturbation of membrane proteins such as Na(+) channels. Since local anesthetics may control the influx of Na(+) into the human erythrocyte, in order to relate the structural perturbations induced by bupivacaine in these systems to Na(+) transport, the interaction of this anesthetic with isolated toad skin was also studied. Electrophysiological measurements indicated a significant decrease in the potential difference and in the short-circuit current of the skin after the application of the anesthetic, reflecting inhibition of the active transport of ions. These results suggest that bupivacaine-induced conformational changes of the lipid molecules alter the lipid-protein boundaries of the outer moiety of the erythrocyte membrane, thus interfering with the function of neighboring sodium channels.


Subject(s)
Anesthetics, Local/pharmacology , Bupivacaine/pharmacology , Erythrocyte Membrane/drug effects , Liposomes/chemistry , Anesthetics, Local/chemistry , Anesthetics, Local/metabolism , Animals , Bufonidae , Bupivacaine/chemistry , Bupivacaine/metabolism , Cell Size/drug effects , Electrophysiology , Erythrocyte Membrane/chemistry , Erythrocyte Membrane/ultrastructure , Erythrocytes/cytology , Humans , Male , Microscopy, Electron, Scanning , Skin/chemistry , Sodium Channels/drug effects , Spectrometry, Fluorescence , X-Ray Diffraction
11.
Z Naturforsch C J Biosci ; 57(9-10): 930-8, 2002.
Article in English | MEDLINE | ID: mdl-12440736

ABSTRACT

Experimental results indicate a significant decrease in the potential difference (PD) and in the short-circuit current (Isc) after the application of proparacaine to isolated toad skin, which may reflect an inhibition of the active transport of ions. This finding was explained on the basis of the results obtained from membrane models incubated with proparacaine. These consisted of human erythrocytes, isolated unsealed human erythrocyte membranes (IUM), phospholipid multilayers built-up of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), representatives of phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively, and in large unilamellar vesicles (LUV) of DMPC X-ray diffraction showed that proparacaine interaction with DMPC and DMPE bilayers perturbed both structures, especially DMPC. This result, confirmed by fluorescence spectroscopy of DMPC LUV at 18 degrees C, demonstrated that the local anesthetic (LA) could interact with the lipid moiety of cell membranes. However, effects observed by scanning electron microscopy (SEM) of human erythrocytes and by fluorescence spectroscopy of IUM might also imply proparacaine-protein interactions. Thus, the LA may alter epitheial sodium channels through interaction with the lipid matrix and with channel protein residues.


Subject(s)
Anesthetics, Local/pharmacology , Cell Membrane/ultrastructure , Erythrocytes/ultrastructure , Propoxycaine/pharmacology , Skin/metabolism , Sodium/metabolism , Animals , Anura , Biological Transport/drug effects , Cell Membrane/drug effects , Cell Membrane/physiology , Erythrocyte Membrane/drug effects , Erythrocyte Membrane/ultrastructure , Erythrocytes/drug effects , Isomerism , Lipid Bilayers/chemistry , Microscopy, Electron, Scanning , Skin/drug effects , Skin Physiological Phenomena
12.
Cranio ; 20(2): 99-104, 2002 Apr.
Article in English | MEDLINE | ID: mdl-12002836

ABSTRACT

In the prognathic (P) patient group clenching at maximal intercuspal position (MIP), we found that the Ar-Go-Me angle is greater than in the control group (C = 120.9 degrees +/- 7 degrees vs. P = 134.4 degrees +/- 5.2 degrees): the same as the masseter fibers angle (alpha). The average EMG voltage class was similar in both groups (C = 1488.5 +/- 303.4 microvolt vs. P = 1317.6 +/- 293.4 microvolt). The mean total number of contact points in tooth arches was greater in the control group than in the patient group (C = 5.77 +/- 0.43 vs. P = 3.07 +/- 0.29), and there was a greater number of contact points between both premolar and molar areas. Both the control group and the patient group showed balanced occlusion in the premolar and molar areas. Therefore the finding of a similar mean EMG value between the control group and the patients emphasizes the importance of balanced contact points in the posterior areas.


Subject(s)
Dental Occlusion , Masseter Muscle/physiopathology , Prognathism/physiopathology , Adult , Case-Control Studies , Cephalometry , Electromyography , Humans , Jaw Relation Record , Muscle Contraction , Reference Values
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