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Sulfates en el cennento portland y su incidencia sobre el falso fraguado:Estado actual del conocimiento IGNACIO DE LA CRUZ ( ) -TOMAS VAZQUEZ -OLGA FERNANDEZ-PEÑA lETCC/CSIC RESUMEN Se realiza un estudio bibliográfico de los sulfatos que pueden estar presentes en el clinker y cemento portland, asi como de los efectos de la aireación y temperatura sobre el fraguado.Este trabajo es la fase previa de una amplia investigación experimental realizada en el JETCC, sobre anomalías de fraguado y fenómenos de "aterronamiento" en el cemento portland. SUMMARYA bibliographical study is carried out of the sulphates which may be present in the clinker and Portland cement, as likewise the effects of the aeration and temperature on the setting. This work is a prior phase of a wide experimental investigation carried out in the lETCC, on anomalies or setting and phenomena of "lumping" in Portland cement. ANTECEDENTESEn el Instituto Eduardo Torroja se está realizando un trabajo de investigación en el cual, a partir de clínkeres industriales, se estudian fenómenos de falso fraguado y de "aterronamiento" de cementos.La investigación está parcialmente concluida y dará lugar a posteriores publicaciones.Forma parte de este estudio el falso fraguado que se observa en ocasiones en cementos aireados y la determinación de los sulfatos a través de espectroscopia IR (*).Con respecto a los sulfatos que pueden estar presentes en el clinker y cemento portland, el estudio se realizó a partir de mezclas binarias, ternarias y cuaternarias de los compuestos. Los análisis se hicieron cuali, semicuanti y cuantitativos (en algunos casos). Se determinó, asimismo, la influencia de la proporción y clase de esos sulfatos sobre la aparición del falso fraguado y la incidencia de la aireación del cemento sobre el fenómeno.Finalmente se explicó el mecanismo causante del falso fraguado en cementos aireados y se adelantaron algunas soluciones que podrían impedir la aparición del fenómeno.

Background The innervated vastus lateralis flap (IVLF) is a barely used possibility for facial palsy reconstruction because of its thickness compared to the gracilis, latissimus dorsi, and pectoralis minor flaps. The aim of this study is to perform a precise description of the intramuscular distribution of the nerve motor branches and its relationship with the vascular pedicle in order to harvest a segmental muscle flap with the best contractile strength to restore facial reanimation. Methods The study was performed on 16 adult cadaver thighs identifying the vastus lateralis muscle and the distribution and relationships of its neurovascular pedicle and branches. We evaluated where the nerve pierced the muscle and the course of the nerve within it. Transverse segments of the nerve were obtained from the proximal and distal ends of the nerve and stained using anti‐ChAT (Choline acetyltransferase) antibodies which are specific of motor neurons. Results A nerve for the vastus lateralis from the posterior division of the femoral nerve divided into 2 branches in 56% of cases; the principal branch coursed along the vascular pedicle and pierced the muscle more proximally than the respective vessels, and a minor branch that pierced the muscle 25–60 mm proximally. There were 3 main intramuscular branches. The nerve length (mean 132.65 ± 22.89 mm) allowed to reach the contralateral side of the face in almost all cases (95%). The mean ChAT positive fibers was 351.0 ± 92.4/mm2 at the proximal end, and 270.3 ± 87.9/mm2 at the distal end (p = 0.49). The number of ChAT negative fibers was higher than ChAT positive in both proximal and distal ends of the nerve. Conclusion We propose the IVLF as a one‐step surgical flap for facial paralysis reanimation due to the constant neurovascular pattern and lengthy pedicle. The amount of motor fibers in several segments of the nerve is appropriate to produce a powerful contraction for dynamic reconstruction.

Objective. Despite the recent advances and innovations in the field of microsurgery and free flaps, vascular anastomoses are still manual and surgeon dependent with traditional methods. The purpose of this study is to evaluate the effectiveness, in the short and medium-term, of glutaraldehyde with bovine serum albumin (BSA) surgical adhesive in the performance of arterial microanastomoses.Material and methods. Fourteen femoral end to end anastomoses (Group 1) and 10 aortic anastomoses (Group 2) were performed in 18 Wistar rats. Flux was measured before, immediately after the anastomoses, and 24 hours later, with a transit-time ultrasound to have quantitative data. Anastomoses technique consisted in using minimal stitches to approximate the vessels and applying BioGlue® adhesive to seal the union. The SSPS® package was used for the statistical study.Results. A median of 2 stitches were necessary in femoral arteries, and 4 stitches in aorta. The median anastomoses time was 16.5 minutes in Group 1 and 32.5 in Group 2. 93% anastomoses of Group 1 and 100% in Group 2, were permeable immediately, and 77% in Group 1 and 100% in Group 2 were permeable after 24 hours, with adequate flux measures. There were no differences in pre and postanastomotic – 24 h aorta-diameter.Conclusions. The use of glutaraldehyde with BSA is a promising technique for the microsurgery of the future, and it is a fast, easy, and reliable alternative to perform microvascular anastomoses, especially when surgeon needs to avoid repeated trauma in the vessel wall or wants to reduce the material inside the lumen and reduce the risk of thrombosis.