Cognitive performance in elderly patients undergoing carotid endarterectomy or carotid artery stenting: a twelve-month follow-up study

BACKGROUND

It is still a matter of debate if and to what extent carotid endarterectomy (CEA) and carotid artery stenting (CAS) impair cognitive functioning in the elderly.

METHODS

We conducted a nonrandomized clinical trial on subjects with asymptomatic carotid artery stenosis comparing CEA (n = 28; 24 males and 4 females; 72.6 +/- 5.8 years old) with CAS (n = 29; 17 males and 12 females; 75.1 +/- 5.7 years old). Cognition, mood and functional status were evaluated by a broad spectrum of tests performed on the day prior to carotid reopening as well as 3 and 12 months after.

RESULTS

No significant differences in scores on cognitive tests including the Babcock story recall test and Rey's auditory verbal learning test (memory), category naming test (verbal fluency), trail-making test parts A and B (attention and executive function) and controlled oral word association test (executive functioning) were observed 3 and 12 months after carotid reopening independent of the technique used. Only scores on the copy drawing test (visuospatial and constructional abilities) slightly but significantly (p < 0.05) worsened in the CAS group 12 months after the intervention. No significant differences between the CEA and CAS groups were detected regarding mood and functional status after 3 and 12 months.

CONCLUSIONS

CEA and CAS seem to be safe procedures in elderly patients in terms of cognitive, mood and functional status in the short and long term. CAS might be preferred for the shorter hospital stay, but further studies with a larger number of old and oldest old subjects with a longer follow-up are needed to better understand the cost-effectiveness of both treatments.

Antitumour response of a double mutant of staphylococcal enterotoxin C2 with the decreased affinity for MHC class II molecule

Staphylococcal enterotoxin C2 (SEC2) is one of the most potent known activators of human T lymphocytes, and recombinant SEC2 shows promising clinical values, but SEC2 can cause food poisoning and toxic shock syndrome in vivo. In this study, site-directed mutagenesis has been used to introduce alanine substitutions at Phe144 and Leu45 in the molecule. The mutant genes were cloned and expressed, and the corresponding proteins were purified by nickel agarose affinity chromatography. We found that the SEC2 mutant proteins could stimulate the proliferation of human peripheral blood lymphocytes and inhibit the growth of tumour cells as native SEC2. Furthermore, flow cytometry assay showed that mSEC2(F44A, L45A) drastically reduced the ability of the toxin to bind to MHC class II. Physiological parameters revealed that mSEC2(F44A, L45A) reduced significantly rat temperature compared with native SEC2 in vivo. Our results clearly suggest that this genetically modified SEC2 protein is less toxic and justifies its further development as a new, safer antitumour superantigen to prevent SEC2 intoxication.

Endoleak after endovascular aortic repair: classification, diagnosis and management following endovascular thoracic and abdominal aortic repair

Endoleak is a common and unique complication of endovascular aortic repair (EVAR) and its persistence represents a failure of the endovascular treatment. Accurate detection and classification is essential for the proper management since the method of endoleak treatment is determined by the different source. In general, high-pressure leaks (type I and type III) require urgent management because of the relatively high short-term risk of sac rupture. Although precise differentiation between type I and type III endoleaks may not be possible at cross- sectional imaging, differentiation is often unnecessary because both lesions are considered high-risk and require angiographic evaluation and subsequent treatment. Low-pressure lesions (types II and V or endotension) are considered less urgent but may warrant continued endovascular evaluation if there is impending growth of the aneurysm sac or if the patient presents with symptoms. Once detected, endoleaks warranting correction (all type I and III; persistent endotension and type II associated with aneurysm enlargement) are usually treated by endovascular route. A variety of techniques including extension endografts or cuff, balloon angioplasty, bare stents and a combination of transvascular and direct sac puncture embolization techniques has allowed to treat the vast majority of these endoleaks without conversion to open surgical repair. Type II endoleak continues to be the most common but also the most controversial in terms of evaluation, the need of treatment, and methods of treatment. Careful and rigorous postoperative lifelong follow-up with computed tomography (CT) and high quality imaging continue to be essential for all patients after EVAR.

Vitamin K2 downregulates the expression of fibroblast growth factor receptor 3 in human hepatocellular carcinoma cells

AIM

Vitamin K2 exerts an antitumor activity on human hepatocellular carcinoma (HCC), however, its inhibitory mechanism has not yet been clarified. This study was designed to identify the attractive target molecule of vitamin K2 and shed some light on its effects on fibroblast growth factor receptor (FGFR)3 in HCC cells.

METHODS

The changes in the gene expression of HuH-7 after vitamin K2 treatment were evaluated by a DNA chip analysis. The mRNA and protein levels of FGFR were evaluated by semiquantitative reverse transcription polymerase chain reaction (RT-PCR), real-time PCR and western blot analysis. The promoter activity of the FGFR3 gene was measured by a dual-luciferase assay.

RESULTS

The DNA chip analysis revealed different inhibitory rates of gene expression of FGFR3 (60.6%) and FGFR1 (19.4%) after vitamin K2 treatment. Vitamin K2 suppresses the proliferation of HuH-7 in a dose-dependent manner and its inhibitory rate reached approximately 61.8% at the dose of 30 microM. FGFR3 mRNA was significantly reduced based on semiquantitative RT-PCR and decreased 61.5% by a real-time PCR method after vitamin K2 treatment, but FGFR1 mRNA was not. The level of FGFR3 protein was also reduced by vitamin K2 treatment. The luciferase assay demonstrated that vitamin K2 significantly suppressed the promoter activity of FGFR3. Furthermore, the FGFR3-ERK1/2 signaling pathway was suppressed by vitamin K2 treatment.

CONCLUSION

These findings suggest that vitamin K2 may suppress the proliferation of HCC cells through the downregulation of the FGFR3 expression. The transcriptional suppression of FGFR3 may be a novel mechanism of the vitamin K2 action for HCC cells.

Yin Yang 1 regulates the transcriptional activity of androgen receptor

The multifunctional protein Yin Yang 1 (YY1) plays an important role in epigenetic regulation of gene expression. YY1 is highly expressed in various types of cancers, including prostate cancer. Currently, the mechanism underlying the functional role of YY1 in prostate tumorigenesis remains unclear. In this report, we investigated the functional interplay between YY1 and androgen receptor (AR), and the effect of YY1 on AR-mediated transcription. We found that YY1 physically interacts with AR both in a cell-free system and in cultured cells. YY1 is required for the optimal transcriptional activity of AR in promoting the transcription of the prostate specific antigen (PSA) promoter. However, ectopic YY1 expression in LNCaP cells did not further enhance the reporter driven by the PSA promoter, suggesting an optimal level of YY1 is already established in prostate tumor cells. Consistently, YY1 depletion in LNCaP cells reduced endogenous PSA levels, but overexpressed YY1 did not significantly increase PSA expression. We also observed that YY1-AR interaction is essential to YY1-mediated transcription activity of AR and YY1 is a necessary component in the complex binding to the androgen response element (ARE). Thus, our study demonstrates that YY1 interacts with AR and regulates its transcriptional activity.

Different types of thoracic endografts

The emerging role of stent-graft strategies for the management of thoracic aortic diseases has attracted growing acceptance, especially in considering the sobering results of open repair in thoracic high-risk settings (e.g., acute dissection, trauma, rupture). Aortic endograft technology for thoracic diseases has rapidly improved after the early use of first generation devices, and the new models show very promising early and mid-term success rates. To date there is no evidence of the superiority of any single device model over the others. Indeed, each device has some peculiarities that makes it more useful in specific settings. Current limitations in thoracic stent-grafts will hopefully be addressed with new designs of highly-individualized low-profile devices in order to extend the applicability of stent-graft technology in the thoracic aorta. Despite progress in configuration and flexibility and the greater availability of different devices compared to a decade ago, shortcomings of specific endovascular grafts including collapse, migration, or dislodgment have not been fully resolved. Nowadays the selection of patients on the basis of favourable anatomy and pathology is the key for the success of the procedure. Not all patients have lesions amenable to stent-graft repair (contraindications for endovascular treatment of thoracic aorta are still not marginal and mainly defined by anatomical constraints) and thoracic endografting is technically challenging, requiring dedicated facilities and experienced specialists. This paper discusses the different configurations and models of stent-graft for thoracic aortic disease as well as the still existing shortcomings.

Relation of promoter methylation of mdr-1 gene and histone acetylation status with multidrug resistance in MCF-7/Adr cells

OBJECTIVE

To analyze the mdr-1 gene promoter methylation and histone acetylation status in both MCF-7/Adr and MCF-7 cells and to preliminarily explore the epigenetic mechanism of multidrug resistance in breast cancer.

METHODS

mdr-1 gene promoter methylation status of the 2 cell lines was detected by methylation-sensitive PCR. mRNA expression of DNA methyltransferases (DNMTs) and histone deacetylases (HDACs) was detected by real-time quantitative PCR. Acetylation level of histone H3 and H4 was examined by optical density assay.

RESULTS

Promoter hypermethylation of mdr-1 gene was observed in MCF-7 cells whereas hypomethylation was found in MCF-7/Adr cells. Expression of DNMT1, DNMT3a, and DNMT3b mRNA in MCF-7/Adr cells significantly decreased compared with that of MCF-7 cells (P<0.05). H3 and H4 histone acetylation levels of MCF-7/Adr cells were obviously higher than those of the MCF-7 cells (P<0.01). Expression of HDAC1, HDAC2, HDAC7, and Sirtuin type 1 (SIRT1) mRNA in MCF-7/Adr cells was significantly reduced (P<0.05).

CONCLUSION

Hypomethylation of the promoter region of mdr-1 gene, high H3 and H4 histone acetylation, and low mRNA expression of DNMTs and HDACs may be important epigenetic factors for the development of MDR in MCF-7/ Adr cells.

Activity of a novel, dual PI3-kinase/mTor inhibitor NVP-BEZ235 against primary human pancreatic cancers grown as orthotopic xenografts

The phosphatidylinositol-3-kinase (PI3K)/Akt signalling pathway is frequently deregulated in pancreatic cancers, and is believed to be an important determinant of their biological aggression and drug resistance. NVP-BEZ235 is a novel, dual class I PI3K/mammalian target of rapamycin (mTor) inhibitor undergoing phase I human clinical trials. To simulate clinical testing, the effects of NVP-BEZ235 were studied in five early passage primary pancreatic cancer xenografts, grown orthotopically. These tumours showed activated PKB/Akt, and increased levels of at least one of the receptor tyrosine kinases that are commonly activated in pancreatic cancers. Pharmacodynamic effects were measured following acute single doses, and anticancer effects were determined in separate groups following chronic drug exposure. Acute oral dosing with NVP-BEZ235 strongly suppressed the phosphorylation of PKB/Akt, followed by recovery over 24 h. There was also inhibition of Ser235/236 S6 ribosomal protein and Thr37/46 4E-BP1, consistent with the effects of NVP-BEZ235 as a dual PI3K/mTor inhibitor. Chronic dosing with 45 mg kg⁻¹ of NVP-BEZ235 was well tolerated, and produced significant tumour growth inhibition in three models. These results predict that agents targeting the PI3K/Akt/mTor pathway might have anticancer activity in pancreatic cancer patients, and support the testing of combination studies involving chemotherapy or other molecular targeted agents.

The pathogenesis of Salmonella enteritidis in experimentally infected ducks: a quantitative time-course study using taqman polymerase chain reaction

Ducks were subcutaneously infected with a high-virulence strain of Salmonella enterica ssp. enterica serovar Enteritidis (Salmonella Enteritidis). The kinetics of the Salmonella Enteritidis genomic DNA loads, the immunohistochemical localization of the bacterial antigens, and the histopathological examination in various tissues were investigated. The results showed that the time course of the appearance of the Salmonella Enteritidis bacterial antigens and the lesions in various tissues was coincident with the bacterial load of the organism in various infected tissues. This suggests that Salmonella Enteritidis loads in systemic organs are closely correlated with the progression of the infection.

Characterization of a Staphylococcus Aureus Strain Showing High Levels of Biofilm Formation Isolated from a Vascular Graft: Case Report

A methicillin-susceptible Staphylococcus aureus strain, SA-DZ1, was isolated from an infected bypass crossover graft. Its general microbiological features were reminiscent of those previously described for the wound Wiley strain. Removal of the prosthetic device was necessary to resolve the infection. SA-DZ1 grown under different conditions showed a very strong and distinctive biofilm-producing phenotype, which was also visualized by confocal laser scanning microscopy. The biofilm extracellular matrix was essentially polysaccharidic, as determined by differential growth and physicochemical tests. By Multi Locus Sequence Typing (MLST), SA-DZ1 was classified as st94, a single locus variant of st8. Several other genetic traits assayed by PCR, such as agr-type and the presence of gene encoding proteins involved in adhesion and virulence (e.g. ica operon), confirmed the identifying features of this clinical isolate.

Outcome after endografting in small and large abdominal aortic aneurysms: a metanalysis

AIM

To compare the results of endovascular repair (EVAR) in large and small (diameter < 5.5cm) abdominal aortic aneurysms (AAA).

METHODS

A systematic review was performed to identify studies comparing the outcomes after EVAR of large and small aneurysms. Outcomes considered were: risk of death (perioperative, all cause, aneurysm-related), ruptures, and complications (conversion, reintervention). Weighted pooled estimates of outcomes in patients with small versus large aneurysms were calculated. The inverse variance method was used (random-effect model). Subgroup analyses by a follow-up longer or shorter than 24 months were performed.

RESULTS

Five studies, with published and unpublished data, totallying 7,735 patients, were included. Overall, the weighted pooled estimates were: OR 0.68; 95% CI 0.51-0.90 for operative mortality, OR 0.77; 95% CI 0.69 to 0.86 for all cause mortality, OR 0.58; 95% CI 0.40 to 0.87 for aneurysm-related mortality and OR 0.61; 95% CI 0.47 to 0.79 for rupture in favour of small AAA group. Pooled estimates were not influenced by follow-up length. Conversion and reintervention rates were not significantly lower for small AAA.

CONCLUSIONS

EVAR in small versus large AAA might be associated with lower operative mortality, aneurysm-related mortality and aneurysm rupture. Better evidence is needed to support these suggestions.

Acute limb ischemia in elderly patients: can iloprost be useful as an adjuvant to surgery? Results from the ILAILL study

OBJECTIVES

To evaluate the effects of iloprost, in addition to surgery, on the outcome of acute lower limb ischemia (ALLI).

DESIGN

Post-hoc analysis of a randomized, double-blind, placebo-controlled study.

METHODS

In the context of the ILAILL (ILoprost in Acute Ischemia of Lower Limbs) study, 192 elderly patients (>70 years old) undergoing surgery for ALLI were assigned to receive perioperative iloprost (intra-arterial, intra-operative bolus of 3000 ng, plus intravenous infusion of 0.5-2.0 ng/kg/min for six hours/day for 4-7 days following surgery), or placebo (iloprost: n=100; placebo: n=92). Patients were followed-up for three-months following surgical revascularization.

RESULTS

The combined incidence of death and amputation (primary study end-point) was significantly reduced in patients treated with iloprost (16.0% vs 27.2% in the placebo group; hazard ratio 1.99, 95% confidence interval 1.05-3.75, p=0.03). A statistically significant lower mortality (6.0%) was reported in patients receiving iloprost, compared to controls (15.2%) (hazard ratio 2.93, 1.11-7.71, p=0.03). The overall incidence of death and major cardiovascular events was lower in patients receiving iloprost compared to those assigned placebo (24.0% and 35.9%, respectively), at the limits of statistical significance (relative risk 1.64, 0.97-2.79, p=0.06).

CONCLUSIONS

These results confirm the poor outcome in elderly patients with ALLI. Based on a subgroup analysis iloprost, as an adjuvant to surgery, appears to reduce the combined end-point of death and amputation.

Timing of complications during carotid artery stenting. How can they be predicted?

Carotid artery stenting (CAS) is becoming increasingly common for the treatment of carotid stenosis. Accumulating data, but not randomised data, suggest that CAS has promising efficacy in preventing stroke with an acceptable rate of procedure-related complications when compared to carotid endarterectomy (CEA). However, CAS procedures can carry a risk of non-negligible complications such as cerebral embolization, cerebral hemorrhage, severe hypotension and bradycardia. These may occur after the first 24 hours. Lessons may be learned from the timing of occurrence of CAS adverse events. The most severe neurological complications are generally due to embolism and occur intraprocedurally especially during catheter, wire or sheath manipulation in the aortic arch and common carotid. These strokes, obviously, cannot be prevented by using cerebral protection devices and enhance the importance of an appropriate learning curve that includes proper material choice, patient selection, good technique and the skill of "know when to quit".

Conversion to Open Repair After Endografting for Abdominal Aortic Aneurysm: Causes, Incidence and Results

OBJECTIVE

To evaluate frequency, causes and results of conversion to Open repair (OR) after endovascular repair (EVAR) in a single centre during an 8-year period.

DESIGN

Six hundred and forty-nine consecutive patients undergoing EVAR were followed up prospectively for endograft-related complications.

OUTCOMES

Early conversion was any OR during or within 30 days from the primary EVAR. Late conversion was any OR with removal of the endograft after 30 days since a completed EVAR procedure.

RESULTS

Median patient follow-up was 38 months (1-93 months). Conversion to OR was performed in 38 patients; nine early and 29 late. Most (7/9) early conversions were due to extensive vessel calcification. Peri-operative mortality was 22% (2/9). Late conversions occurred at a median of 33 months after primary EVAR: 29 were elective and 4 urgent. During the same interval, 79 secondary endovascular interventions were performed, 7 of which failed. The risk of conversion to OR was 9% at 6 years. At multivariate logistic regression analysis, no single factor (short, large or angulated neck, suprarenal fixation, large pre-operative diameter, iliac aneurysms, ASA score risk) was associated with the risk of late failure requiring conversion to OR.

CONCLUSION

The risk of death after early conversion should be recognized, to avoid forcing morphological indications for primary EVAR. Occurrence of late conversion after EVAR is not negligible, affecting almost 1 out of 10 patients after 6 years. In the presence of an expanding aneurysm after EVAR, especially after a failed secondary endovascular correction, an aggressive attitude in fit patients allows outcomes at similar to those of primary OR.

A modified method of activity-based costing for objectively reducing cost drivers in hospitals

OBJECTIVES

Activity-based costing (ABC) is widely used to precisely allocate indirect costs to medical services. In the ABC method, the indirect cost is divided among the medical services in proportion to the volume of "cost drivers", for example, labor hours and the number of hours of surgery. However, the workload of data collection of cost drivers can be time-consuming and a considerable burden if there are many cost drivers. The authors aim to develop a method for objectively reducing the cost drivers used in the ABC method.

METHODS

In the ABC method, the cost driver is assigned for each activity. We assume that these activities and cost drivers are the best combination. Our method, that is cost driver reduction (CDR), can objectively select surrogates of the cost drivers for each activity in ABC from candidate cost drivers. Concretely, the total indirect cost of an activity is temporarily allocated to the medical services using each candidate of cost drivers. The difference between the costs calculated by each candidate and the proper cost driver used in ABC is calculated to evaluate the similarity by the evaluation function.

RESULTS

We estimated the cost of laboratory tests using our method and revealed that the number of cost drivers could be reduced from seven in the ABC to four. Similarly, the results of cost estimation obtained by our method were as accurate as those calculated using the ABC.

CONCLUSIONS

Our method provides two advantages compared to the ABC method: 1) it provides results that are as accurate as those of the ABC method, and 2) it is simpler to perform complicated estimation of hospital costs.

Comparison of surveillance vs Aortic Endografting for Small Aneurysm Repair (CAESAR) trial: study design and progress

OBJECTIVE

The CAESAR Trial aims to assess the outcome of endovascular repair (EVAR) vs surveillance of small abdominal aortic aneurysms (AAA) with maximum diameter of 4.1-5.4 cm on computerised tomography (CT) scan.

DESIGN

Patients between 50 and 80 years of age, with small AAA, anatomically suitable for EVAR, are randomly allocated to early EVAR or surveillance. The primary outcome measure is survival. Secondary endpoints include: aneurysm-related deaths (defined as any death caused directly or indirectly by rupture or endovascular/open aneurysm repair), AAA rupture, peri-operative or late complications, conversion to open repair, complications associated with delayed treatment including loss of treatment options, AAA growth rates and quality of life. Target recruitment is 740 patients to show that early EVAR is associated with a 15% survival benefit at 54 months.

PROGRESS

Randomization started in September 2004. By the end of April 2005, 86 patients had been enrolled by 10 active European centres. Completion of recruitment is expected for September 2006 and publication of the results in mid 2007.