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ABSTRACT Carbonation is a major cause of concrete structures deterioration leading to expensive maintenance and conservation operations. The eco-efficient construction agenda favours the increase of the use of supplementary cementing [...]

Abstract This paper presents an experimental study to evaluate the influence of physical and geometrical properties of granite and limestone aggregates on the durability of a C20/25 strength class concrete. [...]

Nineteen rats were sedated, anesthetized, paralyzed, and mechanically ventilated. The respiratory, lung, and chest wall elastances (Est-rs, Est-L, Est-w); respiratory system, pulmonary, and chest wall total resistances (Rtot-rs, Rtot-L, Rtot-w); respiratory system, pulmonary, and chest wall initial resistances (Rinit-rs, Rinit-L, Rinit-w); and respiratory system, pulmonary, and chest wall difference resistances (Rdiff-rs, Rdiff-L, Rdiff-w) were determined before and after thoracotomy using the end-inflation occlusion method. Rinit reflects the Newtonian resistances and Rdiff represents the viscoelastic/inhomogeneous pressure dissipations in the system. Rtot = Rinit + Rdiff, ie, total resistance. The animals were submitted to either anterolateral thoracotomy (group A, n = 7), median sternotomy (group B, n = 6), or median sternotomy under PEEP while the lungs were exposed (group C, n = 6). In groups A and B, statistically significant increases in Rdiff-rs significantly augmented Rtot-rs. The former results were entirely secondary to significant increases in Rdiff-L, which naturally raised Rtot, L. Resistance was not altered in group C rats. Thus, anterolateral thoracotomy and median sternotomy increases Rtot-rs as a consequence of augmented Rdiff-L, but this finding could be prevented by the use of PEEP. Est-rs and Est-L increased in the three groups after surgery. Groups D and E were comprised of four animals each. Both underwent median sternotomy and in group E, PEEP was applied. Histopathologic examination of the lungs demonstrated a higher degree of lung collapse in group D. (Chest 1993; 104:1882-86) Est = elastances; L-lung, Pel = elastic recoil pressures; Pes = esophageal pressure; PL = transpulmonary pressure; Ptr = tracheal pressure; Rdiff = difference resistances; Rinit = initial resistances; rs = respiratory system; Rtot = total resistances; V = flow; Vr = relaxation volume; w = chest wall, Thoracotomy frequently leads to respiratory impairment. Although a few studies on respiratory mechanics related to thoracotomy have been reported, there are some important aspects still unexplored. Most of the previous [...]

Epileptogenesis in mesial temporal lobe epilepsy is determined by several factors including abnormalities in the expression and function of ion channels. Here, we report a long-lasting deficit in gene expression of Kcnma1coding for the large-conductance calcium-activated potassium (BK, MaxiK) channel -subunits after pilocarpine-induced status epilepticus. By using comparative real-time PCR, Taqman gene expression assays, and the delta-delta comparative threshold method we detected a significant reduction in Kcnma1expression in microdissected dentate gyrus at different intervals after status epilepticus(24 h, 10 days, 1 month, and more than 2 months). BK channels are key regulators of neuronal excitability and transmitter release. Hence, defective Kcnma1expression may play a critical role in the pathogenesis of mesial temporal lobe epilepsy.

Inflammatory pseudotumor of the liver (IPTL) is a rare condition, but an important differential diagnosis of hepatic space-occupying lesions. It may regress spontaneously and mimic other liver tumors. Complications are usually intrahepatic. Herein, we present a case of IPTL which developed pleural empyema and lung necrosis as an uncommon complication.