Juxtarenal aortic aneurysm with hostile neck anatomy: midterm results of minilaparotomy versus f-EVAR

AIM

The aim of this study was to compare the results of complex aneurysm (hostile neck anatomies) repair in high-risk patients with two minimally invasive techniques, fenestrated endografting (f-EVAR where EVAR stands for endovascular aneurysm repair) and minilaparotomy.

METHODS

All high-risk patients (N.=50, group 1) with hostile neck abdominal aortic aneurysms (AAAs) operated in the vascular surgery department of the "Policlinico Universitario G. Martino" of Messina (Italy) during a 5-year period (January 2006-December 2010) were cross-matched with 50 similar patients (group 2) treated in the Vascular Surgery Department of the "Hopital Cardiologique" University of Lille (France) with similar anatomies, comorbidities and risk factors. The patients in group 1 underwent open minilaparotomy surgery, and the patients in group 2 were treated with f-EVAR. The aim of our study was to compare perioperative complications, survival and reintervention rates.

RESULTS

Perioperative cardiac complications occurred in 5 patients (10%) in group 1, and 1 patient (2%) in group 2 (P<0.092). Renal impairment not requiring permanent hemodialysis was significantly higher in group 1 (14% vs. 2% P<0.027), as well as respiratory complications (32% vs. 2% P<0.0001). Five patients (10%) in group 1 underwent reintervention vs. 4 patients in group 2 (P<0.7268). There was no statistically significant difference for survival rates at 30 days (92% in group 1 and 96% in group 2; P=0.399); at six months (90% vs. 96%; P=0.239); at one year (90% vs. 96%; P=0.239); and at two years (84% vs. 94%; P=0.110). However, we observed statistically significant differences in survival rates at three years (74% vs. 94%; P<0.006); at four years (70% vs. 86%; P<0.005); and at five years (65% vs. 68%; P<0.003).

CONCLUSION

Our results showed that both techniques are effective in the treatment of AAA with hostile neck in high-risk patients. Although operative mortality rate was not statistically different, f-EVAR showed better results in terms of early complications and late survival.

The sensibility and specificity of cerebral oximetry, measured by INVOS - 4100, in patients undergoing carotid endarterectomy compared with awake testing

BACKGROUND

Selective shunting during carotid endarterectomy (CEA) is advocated to reduce shunt-related stroke. Cerebral monitoring is essential for temporary carotid shunting. Many techniques are available for cerebral monitoring; however, none is superior to monitoring the patient's neurological status (awake testing) while performing the procedure under local anesthesia (LA). Cerebral oximetry (CO) has previously been used to show the adequacy of cerebral circulation in patients undergoing CEA. This investigation was designed to compare the performance of the INVOS-4100 cerebral oximeter and the neurologic functions, by means of detecting cerebral ischemia induced by carotid cross-clamping, in patients undergoing CEA under LA, namely cervical plexus block.

METHODS

Patients scheduled for CEA under LA were included. Patients converted to general anesthesia (GA) or other types of operations other than CEA were excluded from this study. We enrolled 100 consecutive patients from January 2009 to December 2010. Bilateral regional cerebrovascular oxygen saturation (rSO(2)) was monitored in all patients, in addition to the awake testing. Changes in rSO(2) following carotid artery clamping were recorded. A drop greater than 20% was considered as an indicator of cerebral ischemia that might predict the need for carotid shunting. Patients were only shunted based on the awake testing.

RESULTS

Of the 100 patients undergoing CEA under LA, 9 showed a significant drop in rSO(2) (range: 22.6-32.8%, mean: 26.4%): only three of them required shunting, while the remaining 6 had no changes in consciousness after internal carotid artery (ICA) cross-clamping and it was not necessary to place a shunt (false positive). Compared to the preclamping values, a significant decrease in rSO(2) was found on the hemisphere of the operated side, while no significant change was observed contralaterally. Ninety-one patients had no significant changes of CO values: in 89 of them there was no consciousness deterioration, so we didn't place a shunt (true negative), but 2 patients showing a non-significant post-clamping decline in CO saturation (1.5% and 18.2%) required shunting based on the awake testing (2 false negative). In the current study, the median drop in rSO(2) was 19% (range: 1.5-26.4%) in the 5 patients that required shunting. This represents a sensitivity of 60% and a specificity of 25% for CO in comparison to the awake testing.

CONCLUSION

The results of this study suggest that the usefulness of CO in predicting cerebral ischemia is modest. Cerebral monitoring with INVOS-4100 has a high negative predictive value, but the positive predictive value is low.

Cleavage/polyadenylation factor IA associates with the carboxyl-terminal domain of RNA polymerase II in Saccharomyces cerevisiae

The carboxyl-terminal domain (CTD) of the largest subunit of RNA polymerase II plays an important role in transcription and processing of the nascent transcript by interacting with both transcription and RNA processing factors. We show here that the cleavage/polyadenylation factor IA of Saccharomyces cerevisiae directly contacts CTD. First by affinity chromatography experiments with yeast extracts we demonstrate that the Rna15p, Rna14p, and Pcf11p subunits of this complex are associated with phosphorylated CTD. This interaction is confirmed for Rna15p by yeast two-hybrid analysis. Second, Pcf11p, but not Rna15p, is shown to directly contact phosphorylated CTD based on in vitro binding studies with recombinant proteins. These findings establish a direct interaction of cleavage/polyadenylation factor IA with the CTD. Furthermore, a quantitative analysis of transcription run-on performed on temperature-sensitive mutant strains reveals that the lack of either functional Rna14p or Pcf11p affects transcription termination more severely than the absence of a functional Rna15p. Moreover, these data reinforce the concept that CTD phosphorylation acts as a regulatory mechanism in the maturation of the primary transcript.

Genotype, phenotype, and protein structure in a regulator of sporulation: effects of mutations in the spoIIAA gene of Bacillus subtilis

SpoIIAA, a phosphorylatable protein, is essential to the regulation of sigmaF, the first sporulation-specific transcription factor of Bacillus subtilis. The solution structure of SpoIIAA has recently been published. Here we examine four mutant SpoIIAA proteins and correlate their properties with the phenotypes of the corresponding B. subtilis mutant strains. Two of the mutations severely disrupted the structure of the protein, a third greatly diminished the rate of its phosphorylation and abolished dephosphorylation, and the fourth left phosphorylation unaffected but reduced the rate of dephosphorylation about 10-fold.

Replacement of vegetative sigmaA by sporulation-specific sigmaF as a component of the RNA polymerase holoenzyme in sporulating Bacillus subtilis

Soon after asymmetric septation in sporulating Bacillus subtilis cells, sigmaF is liberated in the prespore from inhibition by SpoIIAB. To initiate transcription from its cognate promoters, sigmaF must compete with sigmaA, the housekeeping sigma factor in the predivisional cell, for binding to core RNA polymerase (E). To estimate the relative affinity of E for sigmaA and sigmaF, we made separate mixtures of E with each of the two sigma factors, allowed reconstitution of the holoenzyme, and measured the concentration of free E remaining in each mixture. The affinity of E for sigmaF was found to be about 25-fold lower than that for sigmaA. We used quantitative Western blotting to estimate the concentrations of E, sigmaA, and sigmaF in sporulating cells. The cellular concentrations of E and sigmaA were both about 7.5 microM, and neither changed significantly during the first 3 h of sporulation. The concentration of sigmaF was extremely low at the beginning of sporulation, but it rose rapidly to a peak after about 2 h. At its peak, the concentration of sigmaF was some twofold higher than that of sigmaA. This difference in concentration cannot adequately account for the replacement of sigmaA holoenzyme by sigmaF holoenzyme in the prespore, and it seems that some further mechanism-perhaps the synthesis or activation of an anti-sigmaA factor-must be responsible for this replacement.