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1.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1535909

RESUMEN

Introduction: Laparoscopic Heller myotomy (LHM) is widely recognized as the standard surgical treatment for esophageal achalasia. However, there is a lack of local data regarding the clinical characteristics of patients and the outcomes of this intervention. Methodology: This retrospective study analyzed patients who underwent LHM over an eight-year period. Demographic, operative, and postoperative variables were assessed. The Eckardt score was used to compare symptoms before and after the intervention. Continuous variables were presented as means. Results: Among the 39 patients assessed, 27 met the inclusion criteria. Of these, 51% were male, with an average age of 48 years. The average lower esophageal sphincter pressure was 36 mmHg. The mean operative time and bleeding were 133 minutes and 34 mL, respectively. The average length of the myotomy was 8.3 cm. Partial fundoplication was performed in all cases, and intraoperative endoscopy was conducted in 88% of the cases. Two intraoperative mucosal perforations occurred. The average length of hospital stay was 2.7 days. There was one medical complication but no mortality. Dysphagia significantly improved by 95%, and the mean Eckardt score decreased from 7.7 to 1.2 after surgery (p < 0.001). The average follow-up period was 24 months. Conclusion: LHM with partial fundoplication proves to be an effective and safe procedure for treating achalasia. It results in the resolution of dysphagia in 95% of cases and carries minimal morbidity. Therefore, LHM should be considered the definitive treatment of choice for achalasia.


Introducción: la miotomía de Heller laparoscópica (MHL) se considera el tratamiento quirúrgico estándar en acalasia esofágica. A nivel local se desconocen las características clínicas de los pacientes y los resultados de la intervención. Metodología: estudio retrospectivo que incluye pacientes llevados a MHL durante un periodo de 8 años. Se analizaron variables demográficas, operatorias y posoperatorias. Mediante el puntaje de Eckardt se compararon síntomas antes y después de la intervención. Las variables continuas se expresan en promedios. Resultados: 27 de 39 pacientes cumplieron los criterios de inclusión. El 51% fueron hombres y el promedio de edad fue de 48 años. La presión promedio del esfínter esofágico inferior fue de 36 mm Hg. El promedio de tiempo operatorio y sangrado fue de 133 minutos y 34 mL, respectivamente. La longitud promedio de la miotomía fue de 8,3 cm. Se adicionó funduplicatura parcial en todos los casos y en el 88% se realizó una endoscopia intraoperatoria. Se presentaron 2 perforaciones intraoperatorias de la mucosa. El promedio de estancia hospitalaria fue 2,7 días. Hubo una complicación médica y ninguna mortalidad. La disfagia mejoró en el 95% y el promedio del puntaje de Eckardt disminuyó de 7,7 a 1,2 luego de cirugía (p < 0,001). El seguimiento fue de 24 meses en promedio. Conclusión: la MHL con funduplicatura parcial es un procedimiento efectivo y seguro para el tratamiento de la acalasia. Se asocia a resolución de la disfagia en el 95% de los casos, su morbilidad es mínima y debe considerarse el tratamiento definitivo de elección.

2.
Front Cell Neurosci ; 12: 12, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29440991

RESUMEN

TRPM4 is a Ca2+-activated non-selective cationic channel that conducts monovalent cations. TRPM4 has been proposed to contribute to burst firing and sustained activity in several brain regions, however, the cellular and subcellular pattern of TRPM4 expression in medial prefrontal cortex (mPFC) during postnatal development has not been elucidated. Here, we use multiplex immunofluorescence labeling of brain sections to characterize the postnatal developmental expression of TRPM4 in the mouse mPFC. We also performed electrophysiological recordings to correlate the expression of TRPM4 immunoreactivity with the presence of TRPM4-like currents. We found that TRPM4 is expressed from the first postnatal day, with expression increasing up to postnatal day 35. Additionally, in perforated patch clamp experiments, we found that TRPM4-like currents were active at resting membrane potentials at all postnatal ages studied. Moreover, TRPM4 is expressed in both pyramidal neurons and interneurons. TRPM4 expression is localized in the soma and proximal dendrites, but not in the axon initial segment of pyramidal neurons. This subcellular localization is consistent with a reduction in the basal current only when we locally perfused 9-Phenanthrol in the soma, but not upon perfusion in the medial or distal dendrites. Our results show a specific localization of TRPM4 expression in neurons in the mPFC and that a 9-Phenanthrol sensitive current is active at resting membrane potential, suggesting specific functional roles in mPFC neurons during postnatal development and in adulthood.

3.
Front Pharmacol ; 8: 918, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29326590

RESUMEN

Protein allosteric modulation is a pillar of metabolic regulatory mechanisms; this concept has been extended to include ion channel regulation. P2XRs are ligand-gated channels activated by extracellular ATP, sensitive to trace metals and other chemicals. By combining in silico calculations with electrophysiological recordings, we investigated the molecular basis of P2X4R modulation by Zn(II) and ivermectin, an antiparasite drug currently used in veterinary medicine. To this aim, docking studies, molecular dynamics simulations and non-bonded energy calculations for the P2X4R in the apo and holo states or in the presence of ivermectin and/or Zn(II) were accomplished. Based on the crystallized Danio rerio P2X4R, the rat P2X4R, P2X2R, and P2X7R structures were modeled, to determine ivermectin binding localization. Calculations revealed that its allosteric site is restricted to transmembrane domains of the P2X4R; the role of Y42 and W46 plus S341 and non-polar residues were revealed as essential, and are not present in the homologous P2X2R or P2X7R transmembrane domains. This finding was confirmed by preferential binding conformations and electrophysiological data, revealing P2X4R modulator specificity. Zn(II) acts in the P2X4R extracellular domain neighboring the SS3 bridge. Molecular dynamics in the different P2X4R states revealed allosterism-induced stability. Pore and lateral fenestration measurements of the P2X4R showed conformational changes in the presence of both modulators compatible with a larger opening of the extracellular vestibule. Electrophysiological studies demonstrated additive effects in the ATP-gated currents by joint applications of ivermectin plus Zn(II). The C132A P2X4R mutant was insensitive to Zn(II); but IVM caused a 4.9 ± 0.7-fold increase in the ATP-evoked currents. Likewise, the simultaneous application of both modulators elicited a 7.1 ± 1.7-fold increase in the ATP-gated current. Moreover, the C126A P2X4R mutant evoked similar ATP-gated currents comparable to those of wild-type P2X4R. Finally, a P2X4/2R chimera did not respond to IVM but Zn(II) elicited a 2.7 ± 0.6-fold increase in the ATP-gated current. The application of IVM plus Zn(II) evoked a 2.7 ± 0.9-fold increase in the ATP-gated currents. In summary, allosteric modulators caused additive ATP-gated currents; consistent with lateral fenestration enlargement. Energy calculations demonstrated a favorable transition of the holo receptor state following both allosteric modulators binding, as expected for allosteric interactions.

4.
J Phycol ; 51(2): 247-54, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26986520

RESUMEN

Adenosine 5'-triphosphate (ATP) is a versatile extracellular signal along the tree of life, whereas cAMP plays a major role in vertebrates as an intracellular messenger for hormones, transmitters, tastants, and odorants. Since red algal spore coalescence may be considered analogous to the congregation process of social amoeba, which is stimulated by cAMP, we ascertained whether exogenous applications of ATP, cAMP, adenine, or adenosine modified spore survival and motility, spore settlement and coalescence. Concentration-response studies were performed with carpospores of Mazzaella laminarioides (Gigartinales), incubated with and without added purines. Stirring of algal blades released ADP/ATP to the cell media in a time-dependent manner. 10-300 µM ATP significantly increased spore survival; however, 1,500 µM ATP, cAMP or adenine induced 100% mortality within less than 24 h; the exception was adenosine, which up to 3,000 µM, did not alter spore survival. ATP exposure elicited spore movement with speeds of 2.2-2.5 µm · s(-1) . 14 d after 1,000 µM ATP addition, spore abundance in the central zone of the plaques was increased 2.7-fold as compared with parallel controls. Likewise, 1-10 µM cAMP or 30-100 µM adenine also increased central zone spore abundance, albeit these purines were less efficacious than ATP; adenosine up to 3,000 µM did not influence settlement. Moreover, 1,000 µM ATP markedly accelerated coalescence, the other purines caused a variable effect. We conclude that exogenous cAMP, adenine, but particularly ATP, markedly influence red algal spore physiology; effects are compatible with the expression of one or more membrane purinoceptor(s), discarding adenosine receptor participation.

5.
Eur J Pharmacol ; 493(1-3): 151-60, 2004 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-15189776

RESUMEN

Anandamide (0.01 to 10 microM) caused greater concentration-dependent reductions of the contractile-induced responses to noradrenaline in female than in male mesenteric vascular beds isolated from adult Sprague-Dawley rats. Greater relaxant responses in females were also induced by the vanilloid TRPV1 receptor agonist capsaicin (0.01 to 10 microM), whereas no sex differences were observed for the relaxations caused by either acetylcholine or sodium nitroprusside. The effect of anandamide in either sex was reduced by the vanilloid TRPV1 receptor antagonist capsazepine but not by the cannabinoid CB1 receptor antagonist N-piperidino-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-3-pyrazole-carboxamide (SR141716A). In males, the anandamide-induced relaxations were potentiated by in vitro exposure during 5 min to 0.5 microM 17beta-oestradiol and unmodified by the protein synthesis inhibitor cycloheximide. The vasorelaxant effects of anandamide in female rats were decreased by ovariectomy. This decrease was prevented by in vivo treatment with 17beta-oestradiol-3-benzoate (450 microg/kg i.m., once a week during 3 weeks) and counteracted by in vitro exposure to oestrogen. In vivo treatment with 17beta-oestradiol also potentiated anandamide-induced responses in males. In conclusion, this study shows an oestrogen-dependent sensitivity to the vanilloid TRPV1 receptor-mediated vasorelaxant effects of anandamide in the mesenteric vasculature of Sprague-Dawley rats, that could be mediated by both genomic and non-genomic mechanisms.


Asunto(s)
Ácidos Araquidónicos/farmacología , Capsaicina/análogos & derivados , Estradiol/análogos & derivados , Estrógenos/fisiología , Mesenterio/efectos de los fármacos , Caracteres Sexuales , Vasodilatación/efectos de los fármacos , Acetilcolina/farmacología , Animales , Ácidos Araquidónicos/antagonistas & inhibidores , Argentina , Capsaicina/farmacología , Chile , Cicloheximida/farmacología , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Endocannabinoides , Estradiol/sangre , Estradiol/inmunología , Estradiol/farmacología , Estrógenos/sangre , Estrógenos/farmacología , Femenino , Masculino , Mesenterio/irrigación sanguínea , Mesenterio/patología , Músculo Liso Vascular/efectos de los fármacos , Nitroprusiato/farmacología , Norepinefrina/antagonistas & inhibidores , Norepinefrina/farmacología , Ovariectomía , Fluoruro de Fenilmetilsulfonilo/farmacología , Piperidinas/farmacología , Alcamidas Poliinsaturadas , Pirazoles/farmacología , Ratas , Ratas Sprague-Dawley , Rimonabant , Factores de Tiempo , Vasodilatación/fisiología
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