Predictive factors for early success of endovascular abdominal aortic aneurysm repair

To identify predictive factors for postoperative success and potential predictors for satisfactory outcome of endovascular grafting for abdominal aortic aneurysm (AAA), we collected data from our prospective database, which includes a series of consecutive patients undergoing endovascular repair at the Vascular Surgery Unit, Policlinico Monteluce, Perugia, Italy. From April 1997 to July 1998, 202 patients were referred to our Unit for elective AAA repair; 94 patients (47%) were selected for endografting. Placement of the graft using endovascular technique without conversion to open laparotomy, in addition to no mortality, major morbidity, or endoleak at 30-day follow-up, was defined as postoperative success. The influence of anatomical features on postoperative results was analyzed by univariate and multivariate analysis. Our experience shows that endoluminal repair of AAA is safe and effective in the short term and male patients with small aneurysms are optimal candidates for successful repair.

[Relationship between the expression of bcl-2 apoptosis and acute myelogenous leukemia prognosis]

In order to check the anti-apoptosis gene bcl-2 protein expression in 58 AML patients we used the immunohistochemical method, and analyse the relationship between bcl-2 protein and prognosis of AML. The result showed that the high expression of bcl-2 protein was related to poor clinical prognosis of AML. This shows that the expression of bcl-2 gene can serve as an index for the prognosis of AML.

Role of duplex scan in endoleak detection after endoluminal abdominal aortic aneurysm repair

OBJECTIVE

to validate the role of duplex scan in endoleak detection in postoperative surveillance of endoluminal abdominal aneurysm repair (EAAR).

PATIENTS AND METHODS

between April 1997 and March 1999, 103 patients were eligible for duplex and computed tomography (CT) scan after EAAR. Mean follow-up was 8 months (range 1-24 months). The study protocol comprised concurrent examination with colour-duplex and CT scan at 1, 6, and 12 months after EAAR, for a total of 198 concurrent examinations. All duplex scan examinations were performed by two vascular surgeons with the same machine (ATL HDI 3000). Interobserver agreement in endoleak detection (kappa=1) and in type of endoleak (kappa=0.7) was evaluated in 50 random duplex examinations. Endoleak detection was examined comparatively in duplex and CT scan, the latter being the gold standard. Sensitivity and specificity tests together with negative- and positive-predictive values (NPV and PPV) were calculated.

RESULTS

duplex scan was not feasible in one patient. On CT scan the endoleak rate was 4% at one month, 3% at 6 months, and 4% at one year. Overall, CT scan detected 12 endoleaks. With respect to endoleak detection, duplex scan revealed a great ability in ruling out false-negative results (sensitivity 91.7%, NPV 99.4%), but overestimated the presence of endoleak (specificity 98.4%, PPV 78. 6%). Regarding type of endoleak, the ability of duplex scan to identify the source of endoleak was low (sensitivity 66.7%).

CONCLUSIONS

duplex scan, if validated, appears to be a reliable means for excluding the presence of endoleak after EAAR.

Eversion versus conventional carotid endarterectomy: late results of a prospective multicenter randomized trial

OBJECTIVE

The durability of carotid endarterectomy (CEA) may be affected by carotid restenosis. The data from randomized trials show that the highest incidence of restenosis after CEA occurs from 12 to 18 months after surgery. The optimal CEA technique to reduce perioperative complications and restenosis rates is still undefined. This study examines the long-term clinical outcome and incidence of recurrent stenosis in patients who undergo eversion CEA. Previously published perioperative results of this study did not show statistically significant differences in study endpoints between the eversion and standard techniques.

METHODS

From October 1994 to March 1997, 1353 patients with surgical indications for carotid stenosis were randomly assigned to undergo eversion (n = 678) or standard CEA (n = 675; primary closure, 419; patch, 256). Withdrawal from the assigned treatment occurred in 1.6% of the patients (in 13 assigned to eversion CEA, and in nine assigned to standard CEA). The clinical and duplex scan follow-up examination was 99% complete, and the mean follow-up interval was 33 months (range, 12 to 55 months). The primary outcomes were perioperative and late major stroke and death, carotid restenosis (stenosis >/= 50% of the lumen diameter detected at duplex scanning), and carotid occlusion. The primary evaluation of study outcomes was conducted on the basis of an intention-to-treat analysis.

RESULTS

Restenosis was found at duplex scanning in 56 patients (19 in the eversion group, and 37 in the standard group). Within the standard group, the restenosis rates were 7.9% in the primary closure population and 1.5% in the patched population. Of the patients with restenosis, 36% underwent cerebral angiography that confirmed restenosis in all cases. The cumulative restenosis risk at 4 years was significantly lower in the group that underwent treatment with eversion CEA as compared with the standard group (3.6% vs 9.2%; P =.01), with an absolute risk reduction of 5. 6% and a relative risk reduction of 62%. Eighteen patients would have had to undergo treatment with eversion CEA to prevent one restenosis during the 4-year period. The incidence rate of ipsilateral stroke was 3.3% in the eversion population and 2.2% in the standard group. There were no significant differences in the cumulative risks of ipsilateral stroke (3.9% for eversion, and 2.2% for standard; P =.2) and death (13.1% for eversion, and 12.7% for standard; P =.7)) in the two groups. Of the 18 variables that were examined for their influence on restenosis, eversion CEA (hazard ratio, 0.3; 95% confidence interval, 0.2 to 0.6; P =.0004) and patch CEA (hazard ratio, 0.2; 95% confidence interval, 0.07 to 0.6; P =. 002) were negative independent predictors of restenosis with multivariate Cox proportional hazards regression analysis.

CONCLUSION

The EVEREST (EVERsion carotid Endarterectomy versus Standard Trial) showed that eversion CEA is safe, effective, and durable. No statistically significant differences were found in late outcome between the eversion and standard techniques at the available follow-up examination.

Mapping the phosphorylation sites of proteins using on-line immobilized metal affinity chromatography/capillary electrophoresis/electrospray ionization multiple stage tandem mass spectrometry

On-line immobilized metal affinity chromatography/capillary electrophoresis/electrospray ionization-mass spectrometry (IMAC/CE/ESI-MS) offers selective preconcentration of phosphorylated peptides with identification of the phosphorylated amino acid(s). The preconcentration provides low concentration limits of detection and capillary electrophoresis separates the peptides. Recently, we reported a fast, simple, and sensitive on-line IMAC/CE/ESI-MS/MS method for the determination of phosphopeptides at low-pmole levels. That work is expanded here by use of multiple stage tandem mass spectrometry (MS(n), n = 2,3) to isolate and fragment target ions to provide more reliable assignments of phosphorylated residues. The application of IMAC/CE/ESI-MS(n) is demonstrated by the analysis of tryptic digests of alpha- and beta-casein and in-gel tryptic digests of beta-casein.

Plasma levels of lipophilic antioxidants in very old patients with type 2 diabetes

BACKGROUND

Experimental research indicates that oxidative stress is implicated in aging and in the pathogenesis of diabetes and its complications. This evidence is limited in elderly patients with non-insulin dependent diabetes, in which age- and disease-related production of reactive oxygen species might exert synergistic damaging effects on tissues and organs.

METHODS

Plasma levels of lipid-soluble compounds with antioxidant properties including vitamin A, vitamin E and carotenoids (lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha- and beta-carotene) were measured by HPLC in 72 elderly patients with non-insulin dependent diabetes (75.7+/-0.8 years, 40 F, 32 M) and in 75 age-matched controls (77.2+/-1.2 years, 48 F, 27 M).

RESULTS

All compounds measured were significantly lower in plasma from diabetic patients as compared to controls (p<0.0001). Plasma levels of vitamins A and E and of carotenoids did not significantly correlate with dietary intake and lipid profile in both groups. In patients, significant inverse correlations were found between age and levels of vitamin E, beta-cryptoxanthin, lycopene and beta-carotene.

CONCLUSIONS

We conclude that patients of very old age with Type 2 diabetes show a poor plasma status of vitamins A and E and carotenoids, which negatively correlates with age. Further studies are needed to explore the possible therapeutic role of lipid-soluble vitamin supplements in elderly diabetic subjects.

A dominant negative mutant of Helicobacter pylori vacuolating toxin (VacA) inhibits VacA-induced cell vacuolation

Most Helicobacter pylori strains secrete a toxin (VacA) that causes structural and functional alterations in epithelial cells and is thought to play an important role in the pathogenesis of H. pylori-associated gastroduodenal diseases. The amino acid sequence, ultrastructural morphology, and cellular effects of VacA are unrelated to those of any other known bacterial protein toxin, and the VacA mechanism of action remains poorly understood. To analyze the functional role of a unique strongly hydrophobic region near the VacA amino terminus, we constructed an H. pylori strain that produced a mutant VacA protein (VacA-(Delta6-27)) in which this hydrophobic segment was deleted. VacA-(Delta6-27) was secreted by H. pylori, oligomerized properly, and formed two-dimensional lipid-bound crystals with structural features that were indistinguishable from those of wild-type VacA. However, VacA-(Delta6-27) formed ion-conductive channels in planar lipid bilayers significantly more slowly than did wild-type VacA, and the mutant channels were less anion-selective. Mixtures of wild-type VacA and VacA-(Delta6-27) formed membrane channels with properties intermediate between those formed by either isolated species. VacA-(Delta6-27) did not exhibit any detectable defects in binding or uptake by HeLa cells, but this mutant toxin failed to induce cell vacuolation. Moreover, when an equimolar mixture of purified VacA-(Delta6-27) and purified wild-type VacA were added simultaneously to HeLa cells, the mutant toxin exhibited a dominant negative effect, completely inhibiting the vacuolating activity of wild-type VacA. A dominant negative effect also was observed when HeLa cells were co-transfected with plasmids encoding wild-type and mutant toxins. We propose a model in which the dominant negative effects of VacA-(Delta6-27) result from protein-protein interactions between the mutant and wild-type VacA proteins, thereby resulting in the formation of mixed oligomers with defective functional activity.

Epidural anesthesia reduces length of hospitalization after endoluminal abdominal aortic aneurysm repair

PURPOSE

The low invasiveness of endoluminal abdominal aneurysm repair (EAAR) appears optimal for the use of epidural anesthesia (EA). However, reported series on EAAR show that general anesthesia (GA) is generally preferred. To evaluate the feasibility and problems encountered with EA for EAAR, patients undergoing EAAR with EA and patients undergoing EAAR with GA were examined.

METHODS

From April 1997 through October 1998, EAAR was performed on 119 patients at the Unit of Vascular Surgery at Policlinico Monteluce in Perugia, Italy. Four patients (3%) required conversion to open repair and were excluded from the analysis because they were not suitable candidates for evaluating the feasibility of EA. The study cohort thus comprised 115 patients undergoing abdominal aortic aneurysm (AAA) repair with the AneuRx Medtronic stent graft. The incidence of risk factors and anatomical features of the aneurysm were compared in patients selected for EA or GA on the basis of intention-to-treat analysis. Intraoperative and perioperative data were compared and analyzed on the basis of intention-to-treat and on-treatment analysis.

RESULTS

Sixty-one patients (54%) underwent the surgical procedure with EA (group A), and 54 (46%) underwent the surgical procedure with GA (group B). Conversion from EA to GA was required in four patients (3 of 61 patients, 5%). There were no statistically significant differences between the two study groups in demographics, clinical characteristics, and American Society of Anesthesiology classification (ASA). There was no perioperative mortality. Major morbidity occurred in 3% of patients (group B). According to intention-to-treat analysis, no significant differences were observed between the two groups in mean operating time, fluoro time, blood loss, amount of contrast media used, mean units of transfused blood, need of intensive care unit, mean postoperative hospital stay, and postoperative endoleak. Conversely, significant differences were found by means of on-treatment analysis in the need of intensive care unit (0 vs 5 patients; P =.02), and length of hospitalization (2.5 vs 3.2 days; P =.04). Multivariate logistic regression analysis showed that GA and ASA 4 were positive independent predictors of prolonged (more than 2 days) postoperative hospitalization (hazard ratio, 2.5; 95% CI, 1.1 to 5.8; P =.03, and hazard ratio, 5.1; 95% CI, 1.5 to 17.9; P =.007, respectively).

CONCLUSION

EA for EAAR is feasible in a high percentage of patients in whom it is attempted, and it ensures a technical outcome comparable with that of patients undergoing EAAR with GA. Successful completion of EAAR with EA is associated with a short period of hospitalization.

Phosphopeptide analysis by on-line immobilized metal-ion affinity chromatography-capillary electrophoresis-electrospray ionization mass spectrometry

The analysis of large phosphoproteins by mass spectrometry is a particular challenge, in many cases, because of the small proportion of phosphopeptides in the presence of a large number of non-phosphorylated peptides. In addition, phosphopeptides are generally available in dilute solutions. Thus, methods to specifically identify phosphopeptides at low concentrations are important. In this work, on-line Fe(III) immobilized metal-ion affinity chromatography (IMAC)-CE-electrospray ionization MS was developed and applied to sub-pmol analysis of phosphopeptides. Phosphopeptides bind Fe(III) with high selectivity. The IMAC resin is packed directly at the head of the CE column. After the phosphopeptides are bonded to the resin and washed, they are eluted at high pH and separated by CE. This method has several advantages: (1) selective retention and pre-concentration of phosphopeptides on an Fe(III)-IMAC resin; (2) a pre-wash of the sample to remove salts and buffers that are not suited for CE separation or ESI operation; (3) facile fabrication with common tools and chemicals (less than 10 min); (4) adaptation to commercial CE instruments without any modifications. The applications of IMAC-CE-MS are demonstrated by the analysis of phosphopeptide mixtures and a phosphoprotein digest.

Endoluminal repair of infrarenal abdominal aortic aneurysms using a modular stent-graft: one-year clinical results from a European multicentre trial

This is a report of a prospective study to evaluate the safety and efficacy of the Medtronic AneuRx stent-graft. Patients with an infrarenal aneurysm with a proximal neck length of greater than 10 mm and a neck diameter not greater than 26 mm and iliac artery diameters of at least 6 mm were accepted for endovascular repair using the Medtronic AneuRx modular stent-graft. A total of 104 patients were included in the study. Transfemoral placement of the bifurcated stent-graft was successful in 102 of 104 patients. Two conversions were performed. The mean operating time was 148 min (range 75-480) and the mean blood loss was 605 ml (range 100-2900). The mean follow-up was 15 months (range 12-21). Complications were rare and no kinking or migration occurred. At follow-up, four endoleaks persisted after 12 months. The Medtronic AneuRx stent-graft is a safe and efficacious alternative to open abdominal aortic aneurysm repair with excellent early results.

Abdominal aortic aneurysms: current management

Optimal management of abdominal aortic aneurysm (AAA) remains a challenging surgical problem. Over the last decade surgical and anesthetic improvements have provided perioperative mortality in the 2% range, when elective AAA repair was performed in single Institutions with large vascular experience. However, community- or national-based mortality rates for elective AAA surgery may be as high as 11% or more. Mortality rates associated with ruptured aneurysms remain as high as 90%. AAA prophylactic resection should be indicated when the risk of rupture exceeds the surgical risk. Although the risk of rupture correlates strongly with the diameter of the AAA, there is evidence that other factors can increase the rupture risk: hypertension, chronic pulmonary disease, aneurysm morphology, etc. Establishing a single threshold diameter for AAA repair appears naive. Moreover, AAA primarily affects older patients with other comorbidities that shorten life expectancy and increase perioperative risks: coronary artery disease, renal and pulmonary insufficiency, peripheral artery disease, etc. So that, proper management of individual AAA is based on balancing the perioperative risk, the risk of rupture, and life expectancy. In the subgroup of young healthy patients with additional risk factors for AAA rupture, elective repair at a smaller size (4 to 5.5 cm) may be beneficial if low surgical risk can be assured. In the last decade endovascular repair for AAA treatment has emerged. These less invasive endovascular techniques for AAA repair offer some advantages in terms of reduced patient stress, analgesic requirement, respiratory dysfunction, blood loss, need for intensive care and reduced hospitalization with an early technical success similar to that of open surgical treatment. However, there are no prospective, randomized studies evaluating endovascular treatment of AAA. Moreover, long-term results on the durability of these new techniques are needed to assess endovascular repair as an alternative treatment to prevent the risk of AAA rupture.

[Progress of surface enhanced Raman spectroscopic studies in nonaqueous systems]

In this report, we describe the applications and theoretical aspects of SERS phenomenon in nonaqueous systems, which mainly involves the structure of solid/nonaqueous system, the adsorption of some neutral and organic molecules, inorganic ions and other complex compound molecules, the process and mechanism of some electrochemical oxidation reduction reactions in organic solvents etc.. In this review, we also depict the similarities and differences in SER spectra of aqueous and non-aqueous systems.

Intraoperative assessment of technical perfection in carotid endarterectomy: a prospective analysis of 1305 completion procedures. Collaborators of the EVEREST study group. Eversion versus standard carotid endartectomy

OBJECTIVE

to define the incidence of technical defects and the impact of technical errors on ipsilateral carotid occlusion, ipsilateral stroke, and early restenosis rates, we analysed 1305 patients undergoing carotid completion procedures.

DESIGN

prospective multicentre study.

PATIENTS AND METHODS

adequacy of CEA was assessed intraoperatively by angiography in 1004 (77%), by angioscopy in 299 (22%), and by duplex scan in two patients (1%). Arteriograms and angioscopic findings were interpreted at the time of the procedure by the operating surgeon, who also established the need for immediate surgical revision.

RESULTS

perioperatively, 13 major strokes (0.9%, all ipsilateral) and six deaths (0.4%) were recorded. Overall, 112 defects (9%) were identified intraoperatively: 81 (72%) were located in the common carotid artery (CCA) or internal carotid artery (ICA), and 31 (28%) in the external carotid artery. In 48 patients (4%) the defects were revised. Logistic regression analysis revealed that carotid plaque extension >2 cm on the ICA was a positive independent predictor of CEA defects (odds ratio (OR) 1.5p=0.03). A significant association was found between the incidence of revised defects of the CCA and ICA and perioperative ipsilateral stroke (OR 11.5p=0.0002). In contrast, patients with minor non-revised defects had an ipsilateral stroke rate comparable to that of patients with no defects (p=0.4). No significant association was found between revised or non-revised defects and occurrence of restenosis/occlusion at 6-month follow-up.

CONCLUSIONS

the incidence of major technical defects during CEA is low, yet the perioperative neurological prognosis of patients with major defects warranting revision is poor. Completion angiography or angioscopy and possible correction of defects did not protect per se from an unfavourable early outcome after CEA. Therefore, surgical excellence is mandatory to achieve satisfactory results after CEA.

Cerebral tomographic findings in patients undergoing carotid endarterectomy for asymptomatic carotid stenosis: short-term and long-term implications

PURPOSE

Preoperative cerebral imaging has been considered not to be cost-effective in carotid endarterectomy (CEA) for asymptomatic carotid stenosis. Yet, silent brain infarction (SBI) has been associated with the embolization potential of a severe carotid stenosis. Thus the presence of SBI may represent an additional indication for CEA in asymptomatic patients. We examined the predictive value of preoperatively detected silent cerebral lesions on early and late outcomes in patients undergoing CEA for asymptomatic carotid stenosis.

METHODS

Preoperative cerebral tomographic (CT) scans performed on 301 asymptomatic patients undergoing 346 CEAs from 1986 to 1995 were reviewed by a single neuroradiologist blinded to patients' records. Mean follow-up was 67. 3 months (range, 24-130 months). The degree of internal carotid lumen reduction was measured bilaterally in all patients (602 carotid arteries); carotid stenosis of 60% or more was found in 399 carotid arteries.

RESULTS

Of the 103 (34%) CT scans positive for cerebral lesions, 58% were lacunar. No significant association was observed between the side of the cerebral lesion on CT scan and the severity of the corresponding carotid stenosis; 38 silent lesions were detected in the 203 hemispheres ipsilateral to carotid stenoses that were less than 60% versus 95 SBIs in the 399 hemispheres ipsilateral to carotid stenoses that were 60% or more (19% vs 24%; P =.2). There were no significant differences in the perioperative stroke/death rate in patients with or without cerebral CT lesions (2% vs 1%; odds ratio, 1.94; P =.6). Mortality rate during follow-up was 22% in patients with preoperative SBI and 15% in patients without SBI (P =.1). However, actuarial survival at 10 years was shorter (P =.02) in patients with SBI. Late stroke occurred in 11% of patients with preoperative SBI and in 3% of patients without preoperative SBI (P =.006). Cox regression analysis showed that both preoperative lacunar and nonlacunar infarctions were independent predictors of late stroke (hazard ratio, 3.6; P =.04; and hazard ratio, 7.1; P =.001; respectively).

CONCLUSION

In our experience, preoperative SBI did not occur more frequently in the hemisphere ipsilateral to asymptomatic severe carotid stenosis. Although our study lacks a medically treated control group, our data show that SBI is predictive of poor neurologic outcome in asymptomatic patients undergoing CEA. We conclude that CT before CEA, selectively applied, provides information on long-term neurologic prognosis and that a less aggressive attitude towards CEA in asymptomatic patients with SBI may be justified.

Hydroquinone as a buffer additive for suppression of bubbles formed by electrochemical oxidation of the CE buffer at the outlet electrode in capillary electrophoresis/electrospray ionization-mass spectrometry

Hydroquinone was found to suppress bubble formation at the outlet electrode of a sheathless capillary electrophoresis/electrospray ionization-mass spectrometer by replacing the oxidation of water (2H2O(1)<-->O2(g) + 4H+ + 4e) with that of more easily oxidized hydroquinone (hydroquinone<-->p-benzoquinone + 2H+ + 2e). Formation of p-benzoquinone replaces the formation of oxygen gas, effectively suppressing gas bubble formation. Several electrode materials, including platinum, gold-coated stainless steel, and stainless steel wires, were tested. However, hydroquinone suppressed bubbles only at the platinum electrode. Combination of the in-capillary electrode sheathless interface using platinum wire, hydroquinone as a buffer additive, and pressure programming at the inlet of the capillary electrophoresis provided a rugged high efficiency interface for analysis of protein digests using CE/ESI-MS.

[Limited diffraction beams and its application]

Limited diffraction beams have a large depth of field and thus have many applications such as medical imaging, tissue characterization, material flaw detection and blood flow detection by Doppler method. Nondiffraction beams colud be produced only by transducer with an infinity large aperture in theory. The experimental results show that limited diffraction beams produced by a limited aperture have desirable large depth of field also. The theory of this kind of beams and their applications in field of medical imaging and blood flow estimation are introduced.

Prospective, randomized, double-blind trial comparing teicoplanin and cefazolin as antibiotic prophylaxis in prosthetic vascular surgery

To compare efficacy, tolerability, and cost of antibiotic prophylaxis with teicoplanin and cefazolin in clean prosthetic vascular surgery, a randomized, prospective, double-blind study was performed at the Vascular Surgery Unit of a tertiary-care university hospital. Two-hundred thirty-eight consecutive patients undergoing elective, clean, abdominal or lower-limb prosthetic vascular surgery were allocated to receive a single intravenous dose of teicoplanin (400 mg) or cefazolin (2 g) at the induction of anesthesia. Surgical-site infections occurred in 5.9% of teicoplanin recipients (4.2% wound infection, 1.7% graft infection) and 1.7% of cefazolin recipients (1.7% wound infection, 0% graft infection) (P=0.195). Other postoperative infections occurred in 10% of teicoplanin recipients (pneumonia 7%, urinary tract infection 3%) and 12% of cefazolin recipients (pneumonia 7%, urinary tract infection 2.5%, bloodstream infections 2.5%). Overall mortality rate was 3.4% in teicoplanin recipients (4 patients) and 2.5% in cefazolin recipients (3 patients). Infective deaths occurred in one patient for each group. The two prophylactic regimens were well tolerated. Cost savings of US $52,510 favoring cefazolin were related to the lower acquisition cost (US $1034 vs US $4740) and to the shorter duration of the hospital stay (1762 days vs 1928 days). Cefazolin can still be regarded as the drug of choice for prophylaxis in clean vascular surgery.

[Omega-mercaptohexanoic acid self-assemble-modified gold electrode and its catalytic property for redox reaction of chlorophylls]

Omega-mercaptohexanoic acid (6-MHA) self-assemble-modified gold electrode has been made by the authors. The SERS spectrum and the variations of double-layer capacitance (Cd) which occurred in the formation of 6-MHA self-assembled monolayers (SAM) on gold electrode surface were studied. The structure model of this SAM was deduced. The results show that 6-MHA can form stable SAM on gold electrode, and this 6-MHA SAM electrode has obvious catalysis for the redox reaction of chlorophylls.

Separation and detection of the alpha- and beta-chains of hemoglobin of a single intact red blood cells using capillary electrophoresis/electrospray ionization time-of-flight mass spectrometry

A single intact red blood cell (erythrocyte) was injected into a capillary electrophoresis column, and following in-capillary lysing the alpha- and beta-chains of the hemoglobin (approximately 450 amol) were separated and detected using capillary electrophoresis/electrospray ionization time-of-flight mass spectrometry. The mass specta of the electropherogram peaks of the alpha and beta chains showed identifiable peaks corresponding to multiply protonated and sodiated alpha- and beta-chains of hemoglobin.

[Studies on purging leukemic cells by photosensitizer PSD-007 laser photoradiation in vitro]

The sensitivity to photosensitization mediated by the hematoporphyrin photosensitizer PSD-007 of acute promyelocytic leukemic cell line (HL-60) was compared with normal human hemopoietic progenitor cells. The results showed that the leukemic cells were more sensitive. After being treated with 10 micrograms.ml-1 PSD-007 followed by 2J.cm-2 copper vapor laser light irradiation, the clonogenic leukemic (HL-60) cells were reduced 98%, but the survival rate of human granulocyte-macrophage colony-forming units (CFU-GM) was 40 +/- 8%. Mixing of normal human marrow cells with leukemic (HL-60) cells (ratio 100:1) did not interfere with elimination of tumor cells. The ultrastructure changes of HL-60 cells treated by laser photoradiation was observed under the trans-electronic microscope. The mitochondria, endoplasmic reticulum and cell membrane were involved. This means that the cell biomembrane is the main target to be attacked. It is considered that PSD-007-laser photoradiation therapy is efficient for killing leukemic cells.

[The changes of electrogastrogram and gastrointestinal pressure following cholecystectomy]

OBJECTIVE

To investigate the mechanism and pathophysiological changes after abdominal surgery.

METHOD

Twenty-two patients after cholecystectomy were selected to perform cutaneous electrogastrography (EGG) at least one hour before operation, and the first, the second and the third day after operation respectively. On the operative and postoperative days, gastroduodenojejunal manometry was performed in 17 of the 2 patients.

RESULT

The percentage of EGG normal frequency on the operative day was obviously lower than that on the preoperative day (P < 0.001), and the percentage of bradygastria on the operative day was obviously higher than that on the preoperative day (P < 0.01). The postoperative EGG amplitude was obviously lower than the preoperative one (P < 0.001), and did not recover after three days. The phase III of the migrating motor complex (MMC) appeared within 24 hours after operation, and first appeared at the duodenum. MMC III was most vigorous at the duodenum in recording period, and was less at the antrum. The contractile power and the area of MMC III at antrum after operation were obviously lower than at duodenum and upper jejunum (P < 0.01). On the third day after operation, the contractile power was lower than normal (P < 0.01).

CONCLUSION

Gastrointestinal motility dysfunction after cholecystectomy is related to EGG amplitude, and not to EGG frequency. The recovery of antrum MMC III is later than that of small bowl, resulting in delayed gastric emptying. The MMC III of small bowl resums in early period after abdominal surgery. Postoperative ileum is due the decrease of MMC III contractile power and the area after abdominal surgery, which represent the ability of gastrointestinal contraction.

Analysis of peptides, proteins, protein digests, and whole human blood by capillary electrophoresis/electrospray ionization-mass spectrometry using an in-capillary electrode sheathless interface

An in-capillary electrode sheathless interface was applied to the capillary electrophoresis/electrospray ionization-mass spectrometry (CE/ESI-MS) analysis of mixtures of small peptides, proteins, and tryptic digests of proteins. The effects of different experimental parameters on the performance of this CE/ESI-MS interface were studied. The distance of the in-capillary electrode from the CE outlet and the length of the electrode inside the capillary had no significant effects on the CE separation and ESI behavior under the experimental conditions used. However, significant enhancement of the sensitivity resulted from the use of narrower CE capillaries. Using a quadrupole mass spectrometer, an aminopropylsilane-coated capillary, and a wide scan mass-to-charge ratio range of 500-1400, detection limits of approximately 4, 1, and 0.6 fmol for cytochrome c and myoglobin were achieved for 75-, 50-, and 30-micron inner diameter capillaries, respectively. Approximately one order of magnitude lower detection limits were achieved under the multiple-ion monitoring mode. The application of the in-capillary electrode sheathless interface to real-world samples was demonstrated by CE/ESI-MS analysis of a human blood sample.

Pressure-assisted and pressure-programmed capillary electrophoresis/electrospray ionization time of flight-mass spectrometry for the analysis of peptide mixtures

Pressure assisting and pressure programming the inlet of the capillary electrophoresis instrument were used for the analysis of peptide mixtures and protein digests using capillary electrophoresis/electrospray ionization-mass spectrometry (CE/ESI-MS). CE/ESI-MS of peptide mixtures and tryptic digests of proteins was studied using three different types of capillary columns: (i) a freshly aminopropylsilane (APS)-treated column, (ii) an untreated column, and (iii) a degraded APS-treated column. To maintain a constant and adequate buffer flow toward the CE capillary outlet for stable CE and ESI operation, low pressure was applied to the inlet of the CE when an untreated or degraded APS capillary was used. By programming the inlet pressure, CE/ESI-MS analysis time was reduced to 1/3 of its original time. The utility of this technique is demonstrated by CE/ESI-MS analysis of a hemoglobin variant (hemoglobin-S) and its tryptic digests. Identification of the mutant peptide in the tryptic digest of hemoglobin-S was achieved by collision-induced dissociation (CID) of the protein digests using CE/ESI time of flight-mass spectrometry (TOF-MS).

Extracellular release of antigenic proteins by Helicobacter pylori

Screening a Helicobacter pylori genomic library with antisera raised against H. pylori broth culture supernatant resulted in the identification of six antigens: urease, HspB, Lpp20, DnaK, MsrA, and a cysteine-rich 28-kDa protein (designated HcpA). H. pylori antigens may be released into the extracellular space by multiple mechanisms, including specific secretion pathways, autolysis, and membrane vesicle formation.

Role of surgical techniques and operative findings in cranial and cervical nerve injuries during carotid endarterectomy

OBJECTIVE

To establish the incidence of cranial and cervical nerve injuries during CEA and their relationship to different surgical techniques and operative findings.

DESIGN

A prospective study.

PATIENTS AND METHODS

From January 1994 to April 1995, 187 consecutive patients undergoing 190 CEAs were evaluated. Pre- and postoperative cranial and cervical nerve assessments were carried out by a single otolaryngologist, blinded to the operative technique and findings. Deficits lasting more than 12 months were defined as permanent. Logistic regression analysis was performed to evaluate the influence of surgical technique, type of anaesthesia, neck haematoma, and plaque extension on the onset of nerve injuries.

RESULTS

Postoperatively, nerve lesions were identified in 51 CEAs (27%) and non-neurological injuries (hemilaryngeal ecchymosis or oedema) causing postoperative dysphonia were present in 80 CEAs (42%). All non-neurological injuries were transient and 98% disappeared within 1 month of surgery. Thirteen (7%) nerve lesions were permanent, but none were disabling. Vagus nerve lesions were significantly associated with long (> 2 cm) carotid plaque (OR = 3.5; CI 1.09-12.37; p = 0.03). Cervical branch lesions were associated with the presence of neck haematoma (OR = 1.9; CI 0.7-4.7; p = 0.05). The incidence of single cranial nerve injuries was higher in patch (OR = 2.7) and eversion (OR = 1.9) procedures than in primary closure. Multiple deficits (2 or more) were most frequent in eversion CEAs (OR = 2.8) and in cases complicated by neck haematoma (OR = 3.8).

CONCLUSIONS

Cranial and cervical nerve lesions during CEA are common. However, our data showed that the majority of local complications are related to transient hemilaryngeal ecchymosis or oedema and, when permanent, are neither clinically relevant nor disabling at 1 year of follow up. Carotid plaque extension and neck haematoma appear to increase the incidence of cranial and cervical nerve lesions during CEA.

A randomized study on eversion versus standard carotid endarterectomy: study design and preliminary results: the Everest Trial

PURPOSE

The EVEREST Trial was designed to determine whether the surgical technique influences the durability and complications of carotid endarterectomy (CEA). The current report focuses on the study design and preliminary results.

METHODS

EVEREST is a randomized multicenter trial. A total of 1353 patients with carotid stenosis requiring surgical treatment were randomly assigned to received standard (n = 675) or eversion (n = 678) CEA. Primary end points included carotid occlusion, major stroke, death, and restenosis rate.

RESULTS

The rate of perioperative major stroke and death (1.3 for each study group) and the incidence of early carotid occlusion (0.6% for eversion vs 0.4% for standard) were similar. No significant differences were found between eversion and standard CEA with respect to incidence of perioperative transient ischemic accident, minor stroke, cranial nerve injuries, neck hematoma, myocardial infarction, or surgical defects as detected with intraoperative quality controls. Clamping time was significantly shorter for eversion CEA compared with patch standard procedures (31.7 +/- 15.9 vs 34.5 +/- 14.4 minutes, p = 0.02). A shunt was inserted in 11% of patients undergoing eversion CEAs and in 16% of patients undergoing standard procedures. Overall 30-day events occurred in 13.3% of the eversion group and in 11.4% of the standard group (p = 0.3). At a mean follow-up of 14.9 months (range, 1 to 38 months), 16 (2.4%) restenoses occurred in the eversion group and 28 (4.1%) occurred in the standard group (odds ratio, 0.56; 95% confidence interval, 0.3 to 1.1; p = 0.08).

CONCLUSION

The preliminary results of the EVEREST Trial suggest that eversion CEA is a safe and rapid procedure with low major complication rates. No significant differences in restenosis rates were observed between eversion and standard CEA at the available follow-up. Longer-term results are necessary to assess whether the eversion technique influences the durability of CEA.

[An experimental study of the formation of osteoclast-like cell in rat bone marrow culture]

OBJECTIVES

To set up a culture method of osteoclast-like cell (OLC) formation in rat bone marrow and to investigate the effects of 1,25(OH)2D3 and osteoblasts on the formation of OLC.

METHODS

The culture of bone marrow from 4-week old rats were studied for the formation of OLC. The culture was divided into four groups: group A, only bone marrow culture as control; group B, bone marrow and osteoblast (from the crania of newborn rats) coculture; group C, bone marrow culture with 1,25(OH)2D3(final concentration 10(-8) mol/L); group D, bone marrow and osteoblast coculture with 1,25(OH)2D3. After 7 days of culture, the number of OLC which was recognized as tartrate resistant acid phosphatase (TRACP) (+) multinucleated cell, the cellular TRACP and the resorption pits on bone slice were examined.

RESULTS

No OLC was present at the beginning of the bone marrow culture in any groups. OLC still failed to be detected in group A by the end of culture, and a few of OLCs could be found out in group B and C. The number of OLC in group D was more than that in the other groups (P < 0.01). The cellular TRACP in group A was lower than that in the other groups, and the cellular TRACP activity in group B and C was lower than that in group D (P < 0.01). In group D, several smaller resorption pits on The bone slice were observed.

CONCLUSION

The formation of OLC requires 1,25(OH)2D3 and coculture with osteoblasts favors the formation of OLC in bone marrow culture.

Capillary electrophoresis/electrospray ionization high mass accuracy time-of-flight mass spectrometry for protein identification using peptide mapping

Capillary electrophoresis/electrospray ionization (CE/ESI) high mass accuracy time-of-flight mass spectrometry was used for the first time to characterize small proteins using peptide mapping. To identify small proteins, the intact proteins were first analyzed to obtain their average molecular weights with errors less than 1 Da. On-line capillary electrophoresis mass spectrometry of the tryptic digests of these small proteins was then performed to obtain the accurate molecular weights of the peptides with accuracies of approximately 10 ppm. Next, this information was used for the identification of the proteins using a protein database. It was found that high mass accuracy is an effective tool in reducing the list of most-likely proteins generated by the database. In addition, on-line collision-induced dissociation of the completely or partially resolved capillary electrophoresis peaks of the protein digests was used to unambiguously identify the sequences of these peptides. Each CE/ESI-MS analysis used only 5 nL of sample containing approximately 120 fmol of each peptide in protein digests. The results indicate that the combination of capillary electrophoresis and high resolution, high mass accuracy time-of-flight mass spectrometry is a viable option for the identification of small proteins using peptide mapping.

Transcranial Doppler monitoring during carotid endarterectomy: is it appropriate for selecting patients in need of a shunt?

PURPOSE

This report summarizes our experience in evaluating a series of 168 patients who underwent a total of 175 carotid endarterectomy procedures under local anesthesia. Patients were monitored by stump pressure (SP) measurement and transcranial Doppler scanning (TCD). The need for shunting was compared between SP/TCD flow velocity reduction and the awake response (gold standard).

METHODS

The study cohort represented 56% of all the carotid patients treated during the study period. Clamping ischemia was defined as the appearance of focal deficit (focal ischemia) or unconsciousness (global deficit) on carotid clamping. In the case of clamping ischemia, a shunt was inserted. To define the optimal value of SP and TCD flow velocity that is able to discriminate patients with clamping ischemia, a receiver operator characteristic (ROC) curve was constructed. Sensitivity and specificity tests, together with negative and positive predictive values (NPV and PPV), were calculated. Cutoff values were defined as the ROC curve values that correlated the highest sensitivity with the highest specificity for both SP and TCD.

RESULTS

Clamping ischemia was present in 18 procedures (10%) in which a shunt was used. No perioperative deaths were recorded. Major perioperative morbidity occurred in one patient (0.6%). Two nondisabling strokes were also recorded (1.8% overall rate of neurologic morbidity). Cutoff values for both SP and TCD, using the ROC curve, were < or = 50 mm Hg and > or = 70% flow velocity reduction from baseline, respectively. SP values of < or = 50 mm Hg or less showed a sensitivity of 100%, a specificity of 83%, a PPV of 40%, and an NPV of 100%. TCD flow monitoring (> or = 70% flow reduction) revealed a lower sensitivity (83%) but a greater ability to avoid false positive results (96% specificity), resulting in increased PPV (71%) and NPV (98%). Combining SP and TCD failed to provide better results in terms of specificity (81%) and PPV (38%).

CONCLUSIONS

SP measurement using a 50 mm Hg cutoff appears to be a reliable predictor of clamping ischemia but requires the use of a shunt in 17% of the patients who would otherwise not require this procedure. In contrast, TCD has greater specificity but is associated with a lower sensitivity, with 17% false negative results. In our experience, both SP and TCD show limitations, as they overestimate or underestimate carotid endarterectomy procedures in need of a shunt. We believe that sensitivity is more important than specificity in carotid endarterectomy, and thus conclude that TCD flow velocity measurement is not an optimal method for detecting clamping ischemia.

Identification of nonprotein amino acids from cycad seeds as N-ethoxycarbonyl ethyl ester derivatives by positive chemical-ionization gas chromatography-mass spectrometry

Nonprotein amino acids from nine species of cycad seeds were analyzed as N-ethoxycarbonyl ethyl ester (ECEE) derivatives by positive chemical-ionization gas chromatography-mass spectrometry. Based on the retention times and mass spectrometry analyses, 12 nonprotein amino acids were identified in these seeds. In addition to the excitatory and putative neurotoxin beta-N-methylamino-L-alanine (BMAA), the known neurotoxin beta-N-oxalylamino-L-alanine (BOAA) was detected from the seeds of Macrozamia moorei and M. communis, and delta-N-oxalyl-ornithine was obtained from the Cycas revoluta seeds. A novel nonprotein amino acid named cycasindene, previously reported from C. revoluta, was also found in the seeds of members of the C. angulata and C. rumphii complex. Eight additional known nonprotein amino acids were also identified. This is the first report of the neurotoxin BOAA from cycad seeds.

Eversion versus conventional carotid endarterectomy: a prospective study

OBJECTIVES

To analyse comparatively eversion and conventional CEA for later association with restenosis, perioperative stroke/death and ipsilateral cerebrovascular events (early, late, disabling and non-disabling).

DESIGN

Prospective non-randomised clinical study.

MATERIALS AND METHODS

A total of 469 patients underwent 514 procedures; 274 (53%) eversion CEA and 240 (47%) conventional CEA. Perioperative monitoring was carried out by clinical evaluation under local anaesthesia or by transcranial Doppler under general anaesthesia. Follow-up was carried out by clinical evaluation and Duplex scanning.

RESULTS

Clamping time was significantly shorter in the eversion group (25.5 +/- 7.4 vs. 28.3 +/- 10.1 min; p = 0.0001; CI delta 4.40/1.12). The perioperative disabling stroke/death rate was 0.7% for eversion vs. 1.2% for conventional CEA, p = 0.6; odds ratio (OR), 0.58. There were two early carotid occlusions (within 30 days) in both groups. According to life-table analysis, after 3 years the probability of > 50% carotid restenosis was significantly lower in the eversion group (2.2% vs. 6.9%, p = 0.03; relative risk reduction 67%). There were no significant differences between the two groups relative to new cerebrovascular events (92% in both groups, p = 0.6). Using multivariate analysis (Cox regression), eversion CEA, and to a lesser extent standard CEA with patch, appeared to protect the vessel from restenosis.

CONCLUSIONS

The eversion technique was associated with reduced clamping time and probability of restenosis. However, because of the nature of a non-randomised study, the present analysis should be confirmed by a multicentre randomised trial.

[Research on omni-directional ultrasonic imaging]

In this paper, an omni-direction M-mode ultrasonic imaging method is introduced, in which M-mode sample line can rotate and move freely. In this way the measurement of parameters such as amplitude and speed of movement of organs can be conducted in any position or direction. We analyzed the sources of errors of the method and the way to overcome them.

High-level genetic diversity in the vapD chromosomal region of Helicobacter pylori

Helicobacter pylori isolates from different patients are characterized by diversity in the nucleotide sequences of individual genes, variation in genome size, and variation in gene order. Genetic diversity is particularly striking in vacuolating cytotoxin (vacA) alleles. In this study, five open reading frames (ORFs) were identified within a 4.2-kb region downstream from vacA in H. pylori 60190. One of these ORFs was closely related to the virulence-associated protein D (vapD) gene of Dichelobacter nodosus (64.9% nucleotide identity). A probe derived from vapD of H. pylori 60190 hybridized with only 19 (61.3%) of 31 H. pylori strains tested. Sequence analysis of the vapD region in vapD-negative H. pylori strains revealed that there were two different families of approximately 0.5-kb DNA segments, which were both unrelated to vapD. The presence of vapD was not associated with any specific family of vacA alleles. These findings are consistent with a recombinational population structure for H. pylori.

Early occurrence and prognostic significance of p53 alteration in primary carcinoma of the fallopian tube

The pathogenesis of primary carcinoma of the fallopian tube (PCFT) is poorly understood. Tumor suppressor p53 gene alterations are common in human malignancies, but their role in the tumorigenesis and survival of PCFT is undefined. The objectives of this study were to define the occurrence and prognostic role of p53 alteration in PCFT and to examine the efficiency of immunohistochemistry (IHC) in detecting p53 alteration in PCFT. Fifty-two PCFT and 10 normal fallopian tubes were examined for p53 alteration by IHC and polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP). The Kaplan-Meier method was used to derive the survival function, while the log-rank test was used to compare curves for two or more groups. Other patients' characteristics were analyzed by two-tailed Fisher's exact tests. IHC correlated well with PCR-SSCP with 100% sensitivity and 83.3% specificity for detecting p53 alteration in this study. Thirty-one of 52 (57%) PCFT showed p53 alteration. Alteration of p53 occurred in all stages of PCFT with a similar incidence in carcinoma in situ and late-stage disease. Alteration of p53 was related to tumor histologic type. Significant survival difference was noted between advanced and early clinical stages but no such difference was identified among different tumor grades. Compared to the p53-nonaltered group, the presence of p53 alteration in PCFT was related to significantly decreased patient survival (RR = 6.8, 95% CI = 2.9-16.2) in multivariate analysis. In the subgroup of patients with residual tumor after surgery, those with p53-altered tumors had a significantly decreased survival compared to those with p53-nonaltered group (RR = 7.4, 95% CI = 1.9-28.2). Alteration of p53 is common and IHC is an efficient method to detect p53 alteration in PCFT. Shorter survival is associated with p53 alteration which is an independent marker for the disease in this study. Alteration of p53 may be an early event in tubal tumorigenesis and may play an important role in the development of PCFT. Whether detection of p53 alteration may serve as an indicator of high-risk patients for whom more aggressive adjuvant chemotherapy may be considered needs to be explored in the future.

Surgical care in octogenarians

The general surgical profile of octogenarians compared with that of younger patients, and risk factors predictive of operative mortality and morbidity, were determined retrospectively using a computer database for all patients admitted between 1989 and 1993. There were 934 admissions of octogenarians and surgery was performed in 447 cases (47.9 percent). The admission rate of patients over 80 years of age increased during the 5-year period from 4.6 to 9.0 per cent, and was significantly higher than that of geriatric patients aged 65-79 years (P < 0.01). Emergency admissions (63.6 percent) and operations (42.3 percent) were more frequent in patients aged over 80 years (P < 0.01); emergency operations increased during the 5 years from 38 to 59 percent. Altogether, 83 deaths and 171 complications were recorded. The mortality rate of octogenarians was greater than that of younger patients (P < 0.01). Postoperative mortality and morbidity rates were 10.1 and 32.2 percent respectively. After multiple logistic regression analysis with stepwise backward elimination, an American Society of Anesthesiologists score of II-V (P < 0.01), the presence of two associated diseases (P < 0.01) and laparotomy procedures (P < 0.03) appeared to be independent risk factors for postoperative mortality and morbidity.

Comparison of target organ damage in renovascular and essential hypertension

In many reports, the prevalence of target organ damage in renovascular hypertension (RVH) appears to be higher than in essential hypertension (EH). Since in most studies the renal artery stenosis is part of a diffuse atherosclerotic disease, it is not known whether these complications are due to RVH itself or to the vascular disease. We have undertaken a case control study of 92 patients divided into two groups (46 in each), one with RVH and the other with EH and abdominal aortic aneurysm, with a comparable degree of diffuse atherosclerotic vascular disease. The vascular state of the extracranial carotid arteries and abdominal and inferior limb districts was investigated with angiography and sonography. The prevalence of left ventricular hypertrophy (LVH) and ischemic heart disease (IHD) were assessed by electrocardiography. Serum creatinine and urinary protein excretion were employed in the renal evaluation. While the analysis of the results confirmed an even diffusion of atherosclerotic vascular disease between the two groups, a significant difference was found in the prevalence of heart and renal damage. LVH was present in 32.6% of RVH patients versus 10.8% in EH (P = .02). Serum creatinine > 1.4 mg/dL was found in 50% of RVH and in 23.9% of EH, (P = .01). The prevalence of proteinuria in RVH was also higher although not reaching the statistical significance. The results suggest that, in patients with comparable degrees of atherosclerotic vascular disease, RVH is responsible for the higher prevalence of target organ damage in this condition compared to those with EH.

[Study on changes of visual fatigue index during prolonged visual display terminal operation]

25 Arabic numerals (0-9) lined in a row were displayed with 4 different patterns on CRT. The subjects were asked to find out the one missed numeral in the row and to press the key corresponding to the numeral. The work lasted for 3h. Longitudino-Kinetic visual acuity was measured before and at 30, 60, 80, 100, 120, 150, 180 minutes during the work. The results showed that the Longitudino-Kinetic visual acuity dropped with working time and recovered after work quickly at first and then slowly.

Computerised tomography findings as a risk factor in carotid endarterectomy: early and late results

OBJECTIVES

To evaluate whether preoperative CT evidence of brain infarction is associated with an increased risk of early and late stroke and death in patients undergoing CEA.

DESIGN

Retrospective clinical study.

MATERIALS AND METHODS

We evaluated 844 CT scanning records from 893 patients undergoing CEA from 1986-1994: 43% (367) CT positive for cerebral infarction and 57% (477) negative. Univariate and multivariate analysis was performed for risk factors and preoperative symptoms in patients with positive and negative CT scans, and Kaplan Meier survival curves for late events.

RESULTS

A positive CT was significantly more frequent in males vs. females (p < 0.0001; O.R. 2.52; C.I. 1.73-3.73), diabetics vs. non-diabetics (p = 0.03; O.R. 1.52; C.I. 1.03-2.26), symptomatics vs. asymptomatics (p < 0.001; O.R. 2; C.I. 1.93-3.53) and contralateral occlusion vs. patency (p < 0.001; O.R. 2; C.I. 1.30-3.10). The perioperative disabling stroke/ death rate was higher in patients with a positive CT (p = 0.002; O.R. 6.27; C.I. 1.73-34.20); in asymptomatic patients this difference was striking (5 patients vs. O, p = 0.0002). Multiple logistic regression analysis for risk factors, CT findings, symptoms preceding surgery, and congruity of brain infarction confirmed a significantly higher incidence of perioperative stroke/death rate (p = 0.003; O.R. 6.37; C.I. 5.12-7.63) and early and late stroke (p = 0.02; O.R. 1.95; C.I. 1.38-2.53) and death (p = 0.0005; O.R. 2.38; C.I. 1.89-2.88) in patients with brain lesions. After 7 years, the survival rate (p = 0.0009) and stroke-free interval (p = 0.003) were lower in patients with a positive CT. After 5 years, in asymptomatic patients the survival rate (p = 0.003) and stroke-free interval (p = 0.01) were lower in the positive CT group.

CONCLUSIONS

A positive CT finding, regardless of congruity of the lesion, should be regarded as an indicator of an increased risk of stroke and death in patients scheduled for carotid surgery, especially in those with asymptomatic stenosis.

p53 overexpression and bcl-2 persistence in endometrial carcinoma: comparison of papillary serous and endometrioid subtypes

Forty-two cases, including 21 uterine papillary serous carcinomas (UPSC) and 21 age-, nuclear-grade-, and clinical-stage-matched uterine endometrioid carcinomas (UEC), were studied immunohistochemically for p53 and bcl-2 in archival paraffin-embedded tissue. Compared to UEC (28.6% positive), UPSC (71.4% positive) had a significantly higher frequency of p53 overexpression (P = 0.005); furthermore, in a clinical-stage-matched fashion, a higher frequency of p53 overexpression was found in early-stage cases (P = 0.032), but not in late-stage cases. In a nuclear-grade-matched comparison, no statistical difference in p53 overexpression was identified between the two subtypes, although UPSC had stronger p53 immunoreactivity than UEC. Of UPSC, no difference in p53 overexpression was detected between tumors of early and late stages; additionally, in 5 cases, there was an abrupt transition from nonstaining morphologically benign glands to uniformly positive p53 nuclear staining in regions of intraepithelial carcinoma. Conversely, in UEC, there was a significant difference in p53 immunostaining between tumors of early and late stages (P = 0.01); no case had an abrupt transition for p53 immunostaining. For bcl-2 immunostaining, UEC had a significantly higher immunohistochemical staining score than did UPSC (P = 0.0002). In general, the staining intensity of bcl-2 diminished progressively from proliferative phase and hyperplastic endometrium to UEC and then to UPSC, with 3 of 21 (14.3%) UPSC being negative. These results suggest that p53 alteration may be an early event in the development of UPSC and may be related to its clinical aggressiveness, while it is a late event in UEC. Early detection of p53 nuclear accumulation may help to identify precursor lesions of UPSC. bcl-2 persistence is frequently associated with endometrial carcinoma, and failure to inactivate bcl-2 expression probably is related to the development of endometrial carcinoma.

[Purification and properties of polysaccharide PPIII from Sterculia lychnophora Hance]

Polysaccharide PP III was isolated and purified from aqueous extract of the seeds of Sterculia lychnophora. It is composed of galactose, arabinose and rhamnose, the molar ratio being 1 : 1.67 : 1.01 and molecular weight 162200. Rhamnoses in the main chain are linked by alpha-(1-->3) glycoside linkage. PP III C is its major fragment, and is composed of galactose and rhamnose with a molar ratio of 1 : 2. 78 and MW 62500.

Mosaicism in vacuolating cytotoxin alleles of Helicobacter pylori. Association of specific vacA types with cytotoxin production and peptic ulceration

Approximately 50% of Helicobacter pylori strains produce a cytotoxin, encoded by vacA, that induces vacuolation of eukaryotic cells. Analysis of a clinically isolated tox- strain (Tx30a) indicated secretion of a 93-kDa product from a 3933-base pair vacA open reading frame. Characterization of 59 different H. pylori isolates indicated the existence of three different families of vacA signal sequences (s1a, s1b, and s2) and two different families of middle-region alleles (m1 and m2). All possible combinations of these vacA regions were identified, with the exception of s2/m1 (p < 0.001); this mosaic organization implies that recombination has occurred in vivo between vacA alleles. Type s1/m1 strains produced a higher level of cytotoxin activity in vitro than type s1/m2 strains; none of 19 type s2/m2 strains produced detectable cytotoxin activity. The presence of cagA (cytotoxin-associated gene A) was closely associated with the presence of vacA signal sequence type s1 (p < 0.001). Among patients with past or present peptic ulceration, 21 (91%) of 23 harbored type s1 strains compared with 16 (48%) of 33 patients without peptic ulcers; only 2 (10%) of 19 subjects harboring type s2 strains had past or present peptic ulcers (p < 0.005). Thus, specific vacA genotypes of H. pylori strains are associated with the level of in vitro cytotoxin activity as well as clinical consequences.

Carotid endarterectomy contralateral to an occluded carotid artery: a retrospective case-control study

OBJECTIVES

To analyse whether contralateral occlusion represents an additional perioperative risk factor in carotid endarterectomy (CEA), and whether long-term survival after surgery in patients with contralateral occlusion differs from that of patients without.

DESIGN

Retrospective clinical study.

SETTING

Vascular Surgery Unit, Department of Surgery, University of Perugia, Perugia, Italy.

MATERIALS

Fifty-five patients with carotid stenosis and contralateral occlusion undergoing CEA (Group 1) were compared with 110 patients (Group II), without contralateral occlusion selected from a cohort of 367 patients with a patent contralateral artery, matched for gender, age and ipsilateral symptoms.

CHIEF OUTCOME MEASURES

Perioperative stroke/death rate at 30 days and minor complications in Group I vs. Group II over a mean follow-up of 38 months.

MAIN RESULTS

The perioperative stroke/death rate at 30 days was 0% in Group I and 2.7% in Group II (p = 0.6) while minor complications amounted to 11% in Group I and 5% in Group II (p = 0.2). Survival rates of patients free from stroke, using Kaplan Meier curves, were 79.4% in Group I and 83.3% in Group II (p = 0.4); stroke free rates were 92.8% and 94.3% in Groups I and II, respectively. The incidence of late stroke, fatal or not, in patients who had undergone CEA with contralateral obstruction was the same as in similarly operated patients without contralateral obstruction (7% vs. 6%). However, the incidence of late vascular death, exemplified by a crude rate of 14% vs. 6% (p = 0.1; O.R. = 2.50; C.I. = 0.77-8.25) was greater in patients with contralateral occlusion.

CONCLUSIONS

In this study, CEA in patients with contralateral occlusion was not associated with an increased perioperative morbidity/mortality rate. The higher incidence of vascular death in the late follow-up of patients with contralateral carotid occlusion, although not statistically significant, could indicate the presence of more severe systemic vascular disease.