Airway Hyperresponsiveness in Asthma Model Occurs Independently of Secretion of ß1 Integrins in Airway Wall and Focal Adhesions Proteins Down Regulation.

The extracellular domains of some membrane proteins can be shed from the cell. A similar phenomenon occurs with ß1 integrins (α1ß1 and α2ß1) in guinea pig. The putative role of ß1 integrin subunit alterations due to shedding in airway smooth muscle (ASM) in an allergic asthma model was evaluated. Guinea pigs were sensitized and challenged with antigen. Antigenic challenges induced bronchoobstruction and hyperresponsiveness at the third antigenic challenge. Immunohistochemistry and immunoelectronmicroscopy studies showed that the cytosolic and extracellular domains of the ß1 integrin subunit shared the same distribution in airway structures in both groups. Various polypeptides with similar molecular weights were detected with both the cytosolic and extracellular ß1 integrin subunit antibodies in isolated airway myocytes and the connective tissue that surrounds the ASM bundle. Flow cytometry and Western blot studies showed that the expression of cytosolic and extracellular ß1 integrin subunit domains in ASM was similar between groups. An increment of ITGB1 mRNA in ASM was observed in the asthma model group. RACE-PCR of ITGB1 in ASM did not show splicing variants. The expression levels of integrin-linked kinase (ILK) and paxillin diminished in the asthma model, but not talin. The levels of phosphorylation of myosin phosphatase target subunit 1 (MYPT1) at Thr(696) increased in asthma model. Our work suggests that ß1 integrin is secreted in guinea pig airway wall. This secretion is not altered in asthma model; nevertheless, ß1 integrin cytodomain assembly proteins in focal cell adhesions in which ILK and paxillin are involved are altered in asthma model. J. Cell. Biochem. 117: 2385-2396, 2016. © 2016 Wiley Periodicals, Inc.

[Middle ear packing with collagen-polyvinylpyrrolidone sponge. Experimental study in guinea pigs]. / Empaquetamiento del oído medio con esponja de colágena polivinil pirrolidona. Estudio experimental en cobayos.

INTRODUCTION: Packing material is mandatory in middle ear (ME) surgery in order to avoid inflammation, adhesions and fibrotic healing. Collagen polivynil-pirrolidone (CPVP) is a healing modulator, which reduces inflammation and fibrosis. Hence we can hypothesize that packing of the ME with CPVP sponge will lead a good ME healing. OBJECTIVE: The aim of this study was to evaluate the otoscopic and microscopic changes induced on the healthy mucosa of the ME and Tympanic membrane (TM) after packing with CPVP sponge in guinea pigs. MATERIAL AND METHODS: Twelve guinea pigs were operated on of right myringotomy. The ME was packed with: Group I (n = 6): Absorbable gelatin sponge (AGS) in SS; Group II (n = 6): CPVP soaked in SS. TM and ME integrity was evaluated otoscopically, as well as residual packing material. Euthanasia was performed on the 4th post-operative week. ME mucosa histologic examination was done. RESULTS: Group I in all the cases showed residual packing material (p < 0.007 Student's test p < 0.001 ANOVA). Histologically both groups presented inflammation with polymorphonuclears, in addition group I showed severe lymphocytosis (p < 0.003 Student's, test p < 0.001, ANOVA). CONCLUSION: The CPVP sponge when it is used as material of packing in the OM of guinea pigs produces less chronic inflammatory changes, but more studies with the injured mucosa are required to validate their utility in the otologic surgery.

Cryopreserved tracheal grafts: a review of the literature.

Cryopreserved tracheal grafts have been used in several experimental models of long segment replacement. The clinical application of the procedure has been limited due to the fact that contradictory results have been reported. The purpose of this article is to present a review of the literature on tracheal cryopreservation. Despite the fact that most authors indicate that cryopreserved tracheal allografts retain viability and have a low immunological response, though they continue to function after transplantation with good epithelialization and patency, cryopreservation leads to significant damage to cartilage, the degree of which is based on the freezing-storage methods that affect the function and durability of a graft. The long-term storage of cartilage must therefore be investigated in more detail in basic research models of cartilage viability: the evaluation of chondrocyte apoptosis, and the use of different solutions for tracheal cryopreservation other than RPMI-1640, Dulbecco's modified Eagle's, Eurocollins, and TC-199. Furthermore, problems that involve improving the blood supply to the graft after extensive resection and immunosuppression must be resolved before tracheal cryopreservation can become a clinically established method for tracheal grafts.

El marcapaso DDD por vía transvenosa / DDD pacemaker implanted intravenously

Se estudiaron en forma retrospectiva 66 pacientes consecutivos, en los que se llevó a cabo la implantación transvenosa de un marcapaso DDD. Las indicaciones fueron: bloqueo AV en 52 pacientes (79 por ciento), disfunción del nodo sinusal en 5 (7.5 por ciento), la combinación de ambos en 4 (6 por ciento) y otras causas en 5(7.5 por ciento). El abordaje fue por punción de la vena subclavia en 38 casos (57.5 por ciento) y por disección de la vena cefálica en 28 (42.5 por ciento). El promedio de seguimiento fue de 16 meses, durante el cual se detectaron complicaciones en 11 pacientes (17 por ciento); en 9 de ellos fue necesario un cambio en el modo de estimulación diferente a DDD, en los otros dos casos se pudo mantener la estimulación DDD con un ajuste en la programación. Dichas complicaciones fueron: A) pérdida de sensado y/o captura atrial en 10 pacientes (en 3 de ellos además se presentó pérdida de la captura ventricular, en otro taquicardia en asa, uno tuvo estimulación diafragmática y otro tuvo una infección severa de la bolsa); B) aparición de fibrilación auricular en un enfermo. El análisis comparativo de las características existentes, en el momento de la implantación del marcapaso, entre el grupo de pacientes con las complicaciones antes mencionadas y el que no las presentó, mostró diferencias significativas: la amplitud de la onda P(1.86 ñ 0.75 mV en el grupo con dichas complicaciones vs. 3.06 ñ 1.52 mV en el grupo sin ellas, P< 0.005), y el umbral de energía de estimulación (1.10 ñ 1.17 µJ en el grupo con complicaciones vs. 0.65 ñ 0.66 µ en el grupo sin complicaciones, p< 0.005). La amplitud de la onda P como el umbral de energía, en el momento de la implantación pueden ser parámetros predictivos de futuras complicaciones