Cross-Seal IDE Trial: Prospective, Multicenter, Single-Arm Study of the Cross-Seal Suture-Mediated Vascular Closure Device System

BACKGROUND

An increasing number of interventional procedures require large-sheath technology (>12F) with a favorable outcome with endovascular rather than open surgical access. However, vascular complications are a limitation for the management of these patients. This trial aimed to determine the effectiveness and safety of the Cross-Seal suture-mediated vascular closure device in obtaining hemostasis at the target limb access site following interventional procedures using 8F to 18F procedural sheaths.

METHODS

The Cross-Seal IDE trial (Investigational Device Exemption) was a prospective, single-arm, multicenter study in subjects undergoing percutaneous endovascular procedures utilizing 8F to 18F ID procedural sheaths. The primary efficacy end point was time to hemostasis at the target limb access site. The primary safety end point was freedom from major complications of the target limb access site within 30 days post procedure.

RESULTS

A total of 147 subjects were enrolled between August 9, 2019, and March 12, 2020. Transcatheter aortic valve replacement was performed in 53.7% (79/147) and percutaneous endovascular abdominal/thoracic aortic aneurysm repair in 46.3% (68/147) of subjects. The mean sheath ID was 15.5±1.8 mm. The primary effectiveness end point of time to hemostasis was 0.4±1.4 minutes. An adjunctive intervention was required in 9.2% (13/142) of subjects, of which 2.1% (3/142) were surgical and 5.6% (8/142) endovascular. Technical success was achieved in 92.3% (131/142) of subjects. Freedom from major complications of the target limb access site was 94.3% (83/88).

CONCLUSIONS

In selected patients undergoing percutaneous endovascular procedures utilizing 8F to 18F ID procedural sheath, Cross-Seal suture-mediated vascular closure device achieved favorable effectiveness and safety in the closure of the large-bore arteriotomy.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03756558.

Long-Term Follow-up of Subjects With Iliac Occlusive Disease Treated With the Viabahn VBX Balloon-Expandable Endoprosthesis

INTRODUCTION

This physician-initiated study provides 5-year (i.e., long-term) treatment durability data from 3 top recruitment sites that participated in the prospective, multicenter, nonrandomized, single-arm VBX FLEX clinical study (ClinicalTrials.gov identifier: NCT02080871). It evaluates the long-term treatment durability of the GORE VIABAHN VBX Balloon Expandable Endoprosthesis (VBX Stent-Graft) in the treatment of subjects with de novo or restenotic aortoiliac lesions.

MATERIALS AND METHODS

A total of 59 subjects with 94 treated lesions were enrolled at the 3 participating sites from the original 140 intent-to-treat subjects in the VBX FLEX study. The primary durability endpoint was long-term primary patency. Secondary long-term outcomes included freedom from target lesion revascularization (TLR), freedom from target vessel revascularization (TVR), as well as resting ankle-brachial index (ABI), Rutherford category, EuroQol 5 Dimensions, and Walking Impairment status.

RESULTS

Fifty-nine subjects participated and twenty-eight (47.5%) were available through the end of the study at 5-year follow-up (the median follow-up time was 6.6 years due to complications resulting from COVID-19 precautions). At 3 and 5 years, the Kaplan-Meier estimates for freedom from all-cause mortality were 94.5% and 81.7%, respectively. The Kaplan-Meier estimates for primary patency at 3 and 5 years were 94.0% and 89.5% (by lesion) and 91.7% and 84.4% (by subject). Primary assisted patency at 3 and 5 years were 93.3% and 93.3%. Kaplan-Meier estimate for freedom from TLR at 5 years was 89.1%. The majority of subjects were asymptomatic (Rutherford category 0) at 3 years (29/59; 72%), and at 5-year follow-up (18/28; 64%). The 5-year mean resting ankle-brachial index was 0.95±0.18, an improvement of 0.15±0.26 from the baseline (p<0.001). Quality of life measures also showed sustained improvement through long-term follow-up.

CONCLUSION

The 5-year long-term follow-up data underscore the robustness and durability of the Viabahn Balloon-Expandable Endoprosthesis for treating aortoiliac occlusive disease.

CLINICAL IMPACT

Durable improvement after endovascular treatment of iliac occlusive disease is clinically important because many of these patients are claudicants with significant life expectancy. This study is the first to evaluate the long-term outcomes in patients with iliac occlusive disease treated with the Viabahn VBX balloon-expandable endopirostheses. The study reports excellent long-term patency outcomes with prolonged clinical benefit. These durable results are likely to be an important consideration for clinicians undertaking iliac artery revascularization procedures.

Signatures of Interactions in the Andreev Spectrum of Nanowire Josephson Junctions

We performed microwave spectroscopy of an InAs nanowire between superconducting contacts implementing a finite-length, multichannel Josephson weak link. Certain features in the spectra, such as the splitting by spin-orbit interactions of the transition lines among Andreev states, have been already understood in terms of noninteracting models. However, we identify here additional transitions, which evidence the presence of Coulomb interactions. By combining experimental measurements and model calculations, we reach a qualitative understanding of these very rich Andreev spectra.

A modular microfluidic bioreactor to investigate plant cell-cell interactions

Plants produce a wide variety of secondary metabolites, which often are of interest to pharmaceutical and nutraceutical industry. Plant-cell cultures allow producing these metabolites in a standardised manner, independently from various biotic and abiotic factors difficult to control during conventional cultivation. However, plant-cell fermentation proves to be very difficult, since these chemically complex compounds often result from the interaction of different biosynthetic pathways operating in different cell types. To simulate such interactions in cultured cells is a challenge. Here, we present a microfluidic bioreactor for plant-cell cultivation to mimic the cell-cell interactions occurring in real plant tissues. In a modular set-up of several microfluidic bioreactors, different cell types can connect through a flow that transports signals or metabolites from module to module. The fabrication of the chip includes hot embossing of a polycarbonate housing and subsequent integration of a porous membrane and in-plane tube fittings in a two-step ultrasonic welding process. The resulting microfluidic chip is biocompatible and transparent. Simulation of mass transfer for the nutrient sucrose predicts a sufficient nutrient supply through the membrane. We demonstrate the potential of this chip for plant cell biology in three proof-of-concept applications. First, we use the chip to show that tobacco BY-2 cells in suspension divide depending on a "quorum-sensing factor" secreted by proliferating cells. Second, we show that a combination of two Catharanthus roseus cell strains with complementary metabolic potency allows obtaining vindoline, a precursor of the anti-tumour compound vincristine. Third, we extend the approach to operationalise secretion of phytotoxins by the fungus Neofusicoccum parvum as a step towards systems to screen for interorganismal chemical signalling.

Differences Between Patients With Intermittent Claudication and Critical Limb Ischemia Undergoing Endovascular Intervention: Insights From the Excellence in Peripheral Artery Disease Registry

BACKGROUND

There are limited data on differences in angiographic distribution of peripheral artery disease and endovascular revascularization strategies in patients presenting with intermittent claudication (IC) and critical limb ischemia (CLI). We aimed to compare anatomic features, treatment strategies, and clinical outcomes between patients with IC and CLI undergoing endovascular revascularization.

METHODS

We examined 3326 patients enrolled in the Excellence in Peripheral Artery Disease registry from 2006 to 2019 who were referred for endovascular intervention for IC (n=1983) or CLI (n=1343). The primary outcome was 1-year major adverse limb events, which included death, repeat target limb revascularization, or target limb amputation.

RESULTS

Patients with CLI were older and more likely to have diabetes and chronic kidney disease and less likely to receive optimal medical therapy compared with IC. Patients with IC had higher femoropopliteal artery interventions (IC 87% versus CLI 65%; P<0.001), while below the knee interventions were more frequent in CLI (CLI 47% versus IC 12%; P<0.001). Patients with CLI were more likely to have multilevel peripheral artery disease (CLI 32% versus IC 15%, P<0.001). Patients with IC were predominantly revascularized with stents (IC 48% versus CLI 37%; P<0.001) while balloon angioplasty was more frequent in CLI (CLI 37% versus IC 25%; P<0.001). All-cause mortality was higher in patients with CLI (CLI 4% versus IC 2%; P=0.014). Major adverse limb event rates for patients with IC and CLI were 16% and 26%, respectively (P<0.001) and remained higher in CLI after multivariable adjustment of baseline risk factors.

CONCLUSIONS

Patients with IC and CLI have significant anatomic, lesion, and treatment differences with significantly higher mortality and adverse limb outcomes in CLI. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01904851. Graphic Abstract: A graphic abstract is available for this article.

From Adiabatic to Dispersive Readout of Quantum Circuits

Spectral properties of a quantum circuit are efficiently read out by monitoring the resonance frequency shift it induces in a microwave resonator coupled to it. When the two systems are strongly detuned, theory attributes the shift to an effective resonator capacitance or inductance that depends on the quantum circuit state. At small detuning, the shift arises from the exchange of virtual photons, as described by the Jaynes-Cummings model. Here we present a theory bridging these two limits and illustrate, with several examples, its necessity for a general description of quantum circuits readout.

Treatment Effect of Drug-Coated Balloons Is Durable to 3 Years in the Femoropopliteal Arteries: Long-Term Results of the IN.PACT SFA Randomized Trial

Supplemental Digital Content is available in the text.

Background—

Randomized controlled trials have reported favorable 1-year outcomes with drug-coated balloons (DCBs) for the treatment of symptomatic peripheral arterial disease when compared with standard percutaneous transluminal angioplasty (PTA). Evidence remains limited on the durability of the treatment effect with DCBs in the longer term.

Methods and Results—

IN.PACT SFA is a single-blind, randomized trial (Randomized Trial of IN.PACT Admiral Paclitaxel-Coated Percutaneous Transluminal Angioplasty [PTA] Balloon Catheter vs Standard PTA for the Treatment of Atherosclerotic Lesions in the Superficial Femoral Artery [SFA] and/or Proximal Popliteal Artery [PPA]) that enrolled 331 patients with symptomatic (Rutherford 2–4) femoropopliteal lesions up to 18 cm in length. Patients were randomized 2:1 to receive treatment with DCB or PTA. The 36-month assessments included primary patency, freedom from clinically driven target lesion revascularization, major adverse events, and functional outcomes. At 36 months, primary patency remained significantly higher among patients treated with DCB compared with PTA (69.5% versus 45.1%; log rank P<0.001). The rates of clinically driven target lesion revascularization were 15.2% and 31.1% (P=0.002) for the DCB and PTA groups, respectively. Functional outcomes were similarly improved between treatment groups even though subjects in the DCB group required significantly fewer reinterventions versus those in the PTA group (P<0.001 for target lesion revascularization, P=0.001 for target vessel revascularization). There were no device- or procedure-related deaths as adjudicated by an independent Clinical Events Committee.

Conclusions—

Three-year results demonstrate a durable and superior treatment effect among patients treated with DCB versus standard PTA, with significantly higher primary patency and lower clinically driven target lesion revascularization, resulting in similar functional improvements with reduced need for repeat interventions.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov. Unique identifiers: NCT01175850 for IN.PACT SFA phase I in the European Union and NCT01566461 for IN.PACT SFA phase II in the United States.

3-Year Clinical Outcomes With Everolimus-Eluting Bioresorbable Coronary Scaffolds: The ABSORB III Trial

BACKGROUND

The Absorb everolimus-eluting poly-L-lactic acid-based bioresorbable vascular scaffold (BVS) provides early drug delivery and mechanical support functions similar to metallic drug-eluting stents (DES), followed by complete bioresorption in approximately 3 years with recovery of vascular structure and function. The ABSORB III trial demonstrated noninferior rates of target lesion failure (cardiac death, target vessel myocardial infarction [TVMI], or ischemia-driven target lesion revascularization) at 1 year in 2,008 patients with coronary artery disease randomized to BVS versus cobalt-chromium everolimus-eluting stents (EES).

OBJECTIVES

This study sought to assess clinical outcomes through 3 years following BVS implantation.

METHODS

Clinical outcomes from the ABSORB III trial were analyzed by randomized treatment assignment cumulative through 3 years, and between 1 and 3 years.

RESULTS

The primary composite endpoint of target lesion failure through 3 years occurred in 13.4% of BVS patients and 10.4% of EES patients (p = 0.06), and between 1 and 3 years in 7.0% versus 6.0% of patients, respectively (p = 0.39). TVMI through 3 years was increased with BVS (8.6% vs. 5.9%; p = 0.03), as was device thrombosis (2.3% vs. 0.7%; p = 0.01). In BVS-assigned patients, treatment of very small vessels (those with quantitatively determined reference vessel diameter <2.25 mm) was an independent predictor of 3-year TLF and scaffold thrombosis.

CONCLUSIONS

In the ABSORB III trial, 3-year adverse event rates were higher with BVS than EES, particularly TVMI and device thrombosis. Longer-term clinical follow-up is required to determine whether bioresorption of the polymeric scaffold will influence patient prognosis. (ABSORB III Randomized Controlled Trial [RCT] [ABSORB-III]; NCT01751906).

3-Year Clinical Outcomes With Everolimus-Eluting Bioresorbable Coronary Scaffolds: The ABSORB III Trial

BACKGROUND

The Absorb everolimus-eluting poly-L-lactic acid-based bioresorbable vascular scaffold (BVS) provides early drug delivery and mechanical support functions similar to metallic drug-eluting stents (DES), followed by complete bioresorption in approximately 3 years with recovery of vascular structure and function. The ABSORB III trial demonstrated noninferior rates of target lesion failure (cardiac death, target vessel myocardial infarction [TVMI], or ischemia-driven target lesion revascularization) at 1 year in 2,008 patients with coronary artery disease randomized to BVS versus cobalt-chromium everolimus-eluting stents (EES).

OBJECTIVES

This study sought to assess clinical outcomes through 3 years following BVS implantation.

METHODS

Clinical outcomes from the ABSORB III trial were analyzed by randomized treatment assignment cumulative through 3 years, and between 1 and 3 years.

RESULTS

The primary composite endpoint of target lesion failure through 3 years occurred in 13.4% of BVS patients and 10.4% of EES patients (p = 0.06), and between 1 and 3 years in 7.0% versus 6.0% of patients, respectively (p = 0.39). TVMI through 3 years was increased with BVS (8.6% vs. 5.9%; p = 0.03), as was device thrombosis (2.3% vs. 0.7%; p = 0.01). In BVS-assigned patients, treatment of very small vessels (those with quantitatively determined reference vessel diameter <2.25 mm) was an independent predictor of 3-year TLF and scaffold thrombosis.

CONCLUSIONS

In the ABSORB III trial, 3-year adverse event rates were higher with BVS than EES, particularly TVMI and device thrombosis. Longer-term clinical follow-up is required to determine whether bioresorption of the polymeric scaffold will influence patient prognosis. (ABSORB III Randomized Controlled Trial [RCT] [ABSORB-III]; NCT01751906).

Pivotal Study of a Next-Generation Balloon-Expandable Stent-Graft for Treatment of Iliac Occlusive Disease

Purpose: To evaluate the safety and efficacy of a next-generation balloon-expandable stent-graft for the treatment of arterial occlusive disease in patients with de novo or restenotic lesions in the common and/or external iliac arteries. Methods: A prospective, multicenter, single-arm safety and efficacy study ( ClinicalTrials.gov identifier: NCT02080871) of the VBX Stent Graft for treatment of de novo or restenotic lesions in the iliac arteries was conducted under an Investigational Device Exemption at 26 US sites and 1 New Zealand center. The study eligibility criteria were established with the aim of enrolling more “real-world” patients compared with previous iliac stent studies supporting Food and Drug Administration approval. The study enrolled 134 patients (mean age 66±9.5 years; 79 men) with 213 iliac lesions. Three-quarters of the population (101, 75.4%) had Rutherford category 3 ischemia, and 43 (32.1%) patients presented with TASC II C/D lesions. The primary endpoint was a composite of device- or procedure-related death within 30 days, myocardial infarction within 30 days, target lesion revascularization (TLR) within 9 months, and amputation above the metatarsals in the treated leg within 9 months. Results: In all, 234 devices were implanted in 213 lesions with 100% technical success; 57 (42.5%) patients received kissing stents at the aortic bifurcation. No devices exhibited a discernable change in length after final deployment as determined by independent core laboratory quantitative angiographic analysis. At 9 months, 3 (2.3%) of 132 patients (1 lost to follow-up, 1 unrelated death) experienced a major adverse event (3 TLRs) related to the primary endpoint. At 9 months, there were no device-related serious adverse events or unanticipated adverse device effects. Conclusion: The next-generation balloon-expandable stent-graft demonstrated notable 9-month safety and efficacy in treating iliac occlusive disease in patients reflecting common clinical practice.

Relation Between Platelet Count and Platelet Reactivity to Thrombotic and Bleeding Risk: From the Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents Study

Whether the association between platelet count (PC) and thrombotic and bleeding risk is independent of or varies by residual platelet reactivity to antiplatelet therapies is unclear. We sought to investigate the independent and combined effects of PC and platelet reactivity on thrombotic and bleeding risk after coronary artery implantation of drug-eluting stents (DES). Patients enrolled in the prospective, multicenter Assessment of Dual AntiPlatelet Therapy with Drug-Eluting Stents study were stratified by PC tertiles. The study cohort comprised 8,402 patients. By linear regression analysis, lower PC was strongly and independently associated with higher platelet reactive units (PRUs) on clopidogrel. After multivariable adjustment (including PRU and aspirin reactive units), high, but not low, PC tertile was independently associated with higher risk of thrombotic complications, including spontaneous myocardial infarction and stent thrombosis. Although no independent association was observed between PC tertiles and hemorrhagic risk, both high and low PC tertiles were associated with increased risk for all-cause mortality. After stratification of PC tertiles by tertiles of PRUs, the crude risk of thrombotic complications was highest in patients in the high PC and high PRU tertiles. By multivariable adjustment, PRU increases were uniformly associated with higher risk of thrombotic events across PC tertiles, without evidence of interaction. In conclusion, higher PCs and higher PRUs act independently and synergistically in determining thrombotic risk. Alongside PRU, PCs could be a simple hematological parameter to consider for risk stratification and in tailoring duration and potency of pharmacologic platelet inhibition after DES implantation.

Electron-Vibration Coupling in Molecular Materials: Assignment of Vibronic Modes from Photoelectron Momentum Mapping

Electron-phonon coupling is one of the most fundamental effects in condensed matter physics. We here demonstrate that photoelectron momentum mapping can reveal and visualize the coupling between specific vibrational modes and electronic excitations. When imaging molecular orbitals with high energy resolution, the intensity patterns of photoelectrons of the vibronic sidebands of molecular states show characteristic changes due to the distortion of the molecular frame in the vibronically excited state. By comparison to simulations, an assignment of specific vibronic modes is possible, thus providing unique information on the coupling between electronic and vibronic excitation.

Wire-Interwoven Nitinol Stent Outcome in the Superficial Femoral and Proximal Popliteal Arteries: Twelve-Month Results of the SUPERB Trial

BACKGROUND

Stent-based therapy in the superficial femoral and popliteal arteries in patients with peripheral artery disease is compromised by restenosis and risk of stent fracture or distortion. A novel self-expanding nitinol stent was developed that incorporates an interwoven-wire design (Supera stent, IDEV Technologies, Inc, Webster, TX) to confer greater radial strength, flexibility, and fracture resistance.

METHODS AND RESULTS

This prospective, multicenter, investigational device exemption, single-arm trial enrolled 264 patients with symptomatic peripheral artery disease undergoing percutaneous treatment of de novo or restenotic lesions of the superficial femoral or proximal popliteal (femoropopliteal) artery. Freedom from death, target lesion revascularization, or any amputation of the index limb at 30 days (+ 7 days) postprocedure was achieved in 99.2% (258/260) of patients (P < 0.001). Primary patency at 12 months (360 ± 30 days) was achieved in 78.9% (180/228) of the population (P < 0.001). Primary patency by Kaplan-Meier analysis at 12 months (360 days) was 86.3%. No stent fracture was observed by independent core laboratory analysis in the 243 stents (228 patients) evaluated at 12 months. Clinical assessment at 12 months demonstrated improvement by at least 1 Rutherford-Becker category in 88.7% of patients.

CONCLUSIONS

The SUPERB Trial, an investigational device exemption study using an interwoven nitinol wire stent in the femoropopliteal artery, achieved the efficacy and safety performance goals predesignated by the Food and Drug Administration. On the basis of the high primary patency rate, absence of stent fracture, and significant improvements in functional and quality-of-life measures, the Supera stent provides safe and effective treatment of femoropopliteal lesions in symptomatic patients with peripheral artery disease.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00933270.

Metabolic mapping reveals sex-dependent involvement of default mode and salience network in alexithymia

Alexithymia, a personality construct marked by difficulties in processing one's emotions, has been linked to the altered activity in the anterior cingulate cortex (ACC). Although longitudinal studies reported sex differences in alexithymia, what mediates them is not known. To investigate sex-specific associations of alexithymia and neuronal markers, we mapped metabolites in four brain regions involved differentially in emotion processing using a point-resolved spectroscopy MRS sequence in 3 Tesla. Both sexes showed negative correlations between alexithymia and N-acetylaspartate (NAA) in pregenual ACC (pgACC). Women showed a robust negative correlation of the joint measure of glutamate and glutamine (Glx) to NAA in posterior cingulate cortex (PCC), whereas men showed a weak positive association of Glx to NAA in dorsal ACC (dACC). Our results suggest that lowered neuronal integrity in pgACC, a region of the default mode network (DMN), might primarily account for the general difficulties in emotional processing in alexithymia. Association of alexithymia in women extends to another region in the DMN-PCC, while in men a region in the salience network (SN) was involved. These observations could be representative of sex specific regulation strategies that include diminished internal evaluation of feelings in women and cognitive emotion suppression in men.

Drug-coated balloon versus standard percutaneous transluminal angioplasty for the treatment of superficial femoral and popliteal peripheral artery disease: 12-month results from the IN.PACT SFA randomized trial

Supplemental Digital Content is available in the text.

Background—

Drug-coated balloons (DCBs) have shown promise in improving the outcomes for patients with peripheral artery disease. We compared a paclitaxel-coated balloon with percutaneous transluminal angioplasty (PTA) for the treatment of symptomatic superficial femoral and popliteal artery disease.

Methods and Results—

The IN.PACT SFA Trial is a prospective, multicenter, single-blinded, randomized trial in which 331 patients with intermittent claudication or ischemic rest pain attributable to superficial femoral and popliteal peripheral artery disease were randomly assigned in a 2:1 ratio to treatment with DCB or PTA. The primary efficacy end point was primary patency, defined as freedom from restenosis or clinically driven target lesion revascularization at 12 months. Baseline characteristics were similar between the 2 groups. Mean lesion length and the percentage of total occlusions for the DCB and PTA arms were 8.94±4.89 and 8.81±5.12 cm (P=0.82) and 25.8% and 19.5% (P=0.22), respectively. DCB resulted in higher primary patency versus PTA (82.2% versus 52.4%; P<0.001). The rate of clinically driven target lesion revascularization was 2.4% in the DCB arm in comparison with 20.6% in the PTA arm (P<0.001). There was a low rate of vessel thrombosis in both arms (1.4% after DCB and 3.7% after PTA [P=0.10]). There were no device- or procedure-related deaths and no major amputations.

Conclusions—

In this prospective, multicenter, randomized trial, DCB was superior to PTA and had a favorable safety profile for the treatment of patients with symptomatic femoropopliteal peripheral artery disease.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov. Unique Identifiers: NCT01175850 and NCT01566461.

Doppler optomechanics of a photonic crystal

A laser beam directed at a mirror attached onto a flexible mount adds friction to its mechanical motion by the Doppler effect. For a normal mirror the efficiency of this radiative Doppler friction is very weak and practically masked by laser shot noise. We find that it can become very efficient using a photonic crystal mirror near its photonic band gaps. As an example, a Bragg mirror used at the long wavelength edge of its band stop can be efficiently optically cooled using the Doppler friction. The opposite effect opens new routes for optical pumping of mechanical systems: a laser pointing at a Bragg mirror and tuned at its short wavelength edge induces amplification of the vibrational excitation of the mirror leading eventually to its self-oscillation. These new effects rely on the strong dependency of a photonic crystal reflectivity on the wavelength.

Randomized Evaluation of the TriActiv Balloon-Protection Flush and Extraction System for the Treatment of Saphenous Vein Graft Disease

OBJECTIVES

The Protection During Saphenous Vein Graft Intervention to Prevent Distal Embolization (PRIDE) study compared outcomes with the TriActiv System (Kensey Nash Corp., Exton, Pennsylvania), a balloon-protection flush and extraction device, with an embolic protection group during treatment of saphenous venous grafts (SVGs).

BACKGROUND

Treatment of SVGs with embolic protection reduces adverse cardiac events.

METHODS

We conducted a prospective trial randomizing 631 patients with coronary ischemia and lesions in SVGs to embolic protection with the TriActiv System or control group (Guardwire System [Medtronic AVE, Santa Rosa, California] or Filterwire EX [Boston Scientific Corp., Maple Grove, Minnesota]).

RESULTS

The incidence of major adverse cardiac events at 30 days was 11.2% for the TriActiv group and 10.1% for the control group (relative risk = 1.1%; 95% confidence interval 0.67 to 1.76; p = 0.65; p = 0.02 for non-inferiority). Safety and efficacy end points were similar between groups except that patients randomized to the TriActiv System had more hemorrhagic complications (10.9% vs. 5.4%; p = 0.01).

CONCLUSIONS

The TriActiv System was not inferior to approved embolic protection devices for the treatment of diseased SVGs.

Comparison of two sites in Mobile Bay using in vivo biomarkers in largemouth bass, sediment bioassays, and sediment contaminant analysis

This research addresses whether chemical contaminants are having a biologically measurable effect on largemouth bass (Micropterus salmoides), an important fish species in the Mobile Bay National Estuary. Bass and sediment samples were collected in September 2001 from Big Bateau and D'Olive Bays; the latter has been suggested to be an environmentally impacted site. There was a significant difference in the age distribution of bass collected from the two sites. However, none of the animals showed any evidence of reproductive activity or had mature gametes. The age and gonadosomatic index were greater in animals collected from the Bateau site. Fish liver microsome ethoxyresorufin-O-deethylase (EROD) activities (elevated in the presence of CYP1A-inducing contaminants) were not significantly different between sites but were significantly higher in older bass. Plasma steroid concentrations in younger animals (less than 1 year old) tended to be higher and more variable than the concentrations found in older animals. Once the significant effects of age on plasma steroid concentrations were removed, an analysis of the residual change in steroids revealed no differences in testosterone or estradiol between animals collected at the two sites. Sediments were collected for chemical extraction and analysis in two bioassays: the H4IIE rat hepatoma EROD assay and the yeast estrogen screen (YES assay). The H4IIE bioassay indicated the presence of sediment BaP induction equivalents between 72 and 320 ng/g, whereas the YES assay indicated that potent estrogenic substances were not present in the sediment samples. The H4IIE bioassay results were higher for D'Olive samples, which was consistent with higher PAH concentrations in those sediments. Taken together the biomarkers and chemical analysis suggested generally low organic contamination at these two sites.

[The use of rapid tests for individual diagnosis of influenza]

Antiviral therapy against influenza requires the beginning of treatment within 36 to 48 h after the onset of symptoms. With the availability of the neuraminidase inhibitors which are effective against influenza A and B a rapid diagnosis of influenza is of increasing interest. A diagnosis during the first consultation would be ideal for treatment. This can be achieved with clinical diagnosis and with quick tests that can be conducted in the practice (point of care test). The costs of such virological examinations have to be considered in relation to the use of information they create. The cost benefit relation is discussed in relation with different epidemic situations. The benefit and additional information of tests for individual diagnosis is high when the incidence of influenza is low, while in periods with high incidences the clinical diagnosis alone appears sufficient.

First outbreak of callitrichid hepatitis in Germany: genetic characterization of the causative lymphocytic choriomeningitis virus strains

Callitrichid hepatitis (CH) is a highly fatal, rodent-borne zoonosis of New World primates (family Callitrichidae) caused by lymphocytic choriomeningitis virus (LCMV). It is unclear whether virulence in Callitrichidae is associated with specific genetic or phylogenetic markers of the virus as only a partial S RNA sequence of a single CH-associated isolate is known. In a period of 10 months, three pygmy marmosets (Cebuella pygmaea) and one Goeldi's monkey (Callimico goeldii) died from CH in a German zoo. LCMV was most likely transmitted by wild mice. Infection was associated with characteristic histopathological lesions in liver, brain, and lymphoid tissue. Virus sequences from all callitrichids and a captured mouse were > or =99.2% identical. LCMV strains from a pygmy marmoset and the Goeldi's monkey were isolated in cell culture and the 3.4-kb S RNA was completely sequenced. Both strains differed considerably in their genetic and phylogenetic characteristics from known LCMV strains, including the previously described CH-associated strain. These data show that CH is widespread and can be caused by distantly related LCMV strains.

[Rational and efficient enterovirus diagnosis]

BACKGROUND AND OBJECTIVE

Demonstration of the causative pathogen by isolating the virus in cell culture is taken as the standard in the diagnosis of diseases caused by enterovirus. When diagnosing the virus in cerebrospinal fluid (CSF), isolation of the virus has been largely replaced by the rapid demonstration of the virus using the reverse transcriptase polymerase chain reaction (RT-PCR), because of its greater sensitivity. The serological diagnosis is mostly made with the complement binding reaction (CBR). A new enzyme immunoassay for demonstrating anti-enterovirus IGM antibodies (IgM-EIA) allows a more rapid diagnosis from a single serum sample. It was the aim of this study to compare the diagnostic value of these various tests.

METHODS

Several methods for demonstrating virus from faeces, swabs and CSF (virus isolation in cell culture and RT-PCR) and of antibodies in serum (IgM-EIA and CBR) were compared. The clinical material was obtained largely from children under the age of 10 years, many of whom had serous meningitis, flu-like symptoms or enteritis. In one cohort (C1), only stool or throat swabs were available for each of 154 patients. In the other cohort (C2) of 164 patients, CSF and at least one serum sample were available in addition to occasional stool samples.

RESULTS

From C1 enteroviruses were isolated from 32 patients. rotavirus twice from stool or throat swab and rotavirus once from stool or throat swab, and herpes simplex once from throat swab. RT-PCR was positive 55 times for enterovirus, five times false-negative when the virus had been isolated. In C2 enterovirus nucleic acid was demonstrated in 43 patients from CSF. Parallel serological tests gave positive IgM values for 15 patients, while CBR titres were raised in nine.

CONCLUSIONS

Complementary tests of CSF, stool, swabs and serum samples by all possible combinations of viral isolation, RT-PCR and IgM-EIA improve the diagnosis of enterovirus-associated diseases. RT-PCR is the method of choice. The serological diagnosis should be confirmed by the demonstration of virus in stool or swab.

Evaluation of enterovirus serological tests IgM-EIA and complement fixation in patients with meningitis, confirmed by detection of enteroviral RNA by RT-PCR in cerebrospinal fluid

An enzyme immunoassay (EIA) for detection of anti-enterovirus IgM antibodies was compared with complement fixation test in 43 patients with confirmed enterovirus meningitis by RT-PCR of cerebrospinal fluids (CSF). In 34% of patients with enterovirus meningitis, IgM antibodies could be found, whereas complement fixation tests were positive in only 20%. The specificity was determined with sera of 105 patients with non-enterovirus meningitis. Specificity of IgM EIA and of complement fixation was 94% and 85%, respectively. In four patients with meningitis but without enterovirus detection in CSF, RT-PCR and virus isolation from stools were positive. In three of these patients, IgM antibodies were detected, giving a strong indication of an enterovirus-associated disease. Because of the high specificity of IgM EIA, diagnosis of enterovirus-associated diseases can be carried out in a single serum sample, whereas by complement fixation tests, only fourfold increases in antibody titres in paired sera indicate an acute infection. The application of IgM EIA is especially important in cases of meningitis when CSF samples are not available and for diagnosis of enterovirus diseases with other clinical symptoms such as fever, enteritis, and hand-foot-and-mouth disease.

A new enzyme immunoassay for the detection of enteroviruses in faecal specimens

A new enzyme immunoassay (EIA) for direct detection of enteroviruses based on a group-specific monoclonal antibody was evaluated using stool samples from patients with suspected enteroviral infection. The EIA was compared with polymerase chain reaction (PCR) and virus isolation in cell culture. Of 204 samples tested, 20 were positive by EIA, 34 by PCR, and 18 by cell culture. Compared with PCR, the most sensitive method, the sensitivity of EIA was 58% (20/34); the sensitivity of cell culture isolation was 52% (18/34). The results of both assays correlated in only 60% of cases. The combination of EIA and cell culture isolation detected 76% of PCR-positive stool samples. Enterovirus EIA provides results within 3-4 hr and requires only standard EIA equipment. It represents a rapid, reliable, and cost-effective diagnostic tool for enterovirus diagnosis from faecal samples. Negative results must be confirmed by other techniques, such as PCR or virus isolation in cell culture.

Dehydroepiandrosterone increases the zone [correction of in zone] of glutamine synthetase-positive hepatocytes in female rat liver: a putative androgenic effect

The adrenal steroid dehydroepiandrosterone (DHEA) is a hepatocarcinogen and peroxisome proliferator in the rat, producing an increase in peroxisomes mainly in perivenular parts of the liver lobule. Glutamine synthetase (GS) is expressed exclusively in hepatocytes that directly surround the central terminal vein in rat liver. The GS-positive zone is wider in males than in females, covering about two to three cell layers in males and one to two cell layers in females. Treatment of rats with DHEA at a concentration of 0.6% in the diet for 4, 20, 32, 70 and 84 weeks resulted in an enlargement of the GS-positive zone in females, whereas no change was observed in males. In females treated for up to 32 weeks with DHEA, the relative mean width (RMW) of the GS-positive zone was as large as that observed in males. The increase in the RMW was paralleled by an increase in the number of GS-positive hepatocytes. Upon longer treatment, the width of GS expression decreased to that observed in untreated controls. The findings suggest an androgenic effect of DHEA. The areas of peroxisome proliferation, identified in haematoxylin and eosin- and periodic acid-Schiff-stained sections, and GS expression were not identical. Furthermore, preneoplastic and neoplastic liver lesions induced by DHEA were all negative for GS, indicating that they do not derive from the perivenular cells which show the most pronounced peroxisomal proliferation.

Differentiation between acute primary and recurrent human cytomegalovirus infection in pregnancy, using a microneutralization assay

Acute primary human cytomegalovirus (HCMV) infection in pregnancy, the major cause of congenital symptomatic infection, is often difficult to differentiate from recurrent infection, which presents a considerably smaller risk to the fetus. Therefore, the diagnosis of primary infection in pregnancy is very important, especially if seroconversion is not documented and follow-up sera with declining IgM-titers are not available. To investigate the value of the neutralizing antibody response against HCMV in differentiating acute primary from recurrent and past infection, well-characterized sera from pregnant women were examined. Employing a microneutralization assay, it was found that neutralizing antibodies first appeared approximately 15 weeks after acute infection. However, serum samples of pregnant women with recurrent or past infection consistently displayed neutralizing activity. In conclusion, the neutralization assay can be used as a reliable method for discriminating acute primary from previous or recurrent infection in a single serum sample.

A new method for flat-embedding large native cryostat sections for targeting small preneoplastic lesions in comparative ultrastructural and ultracytochemical investigations

Ultrastructural studies of rare and small cellular lesions in pathologically altered tissue are difficult to perform by applying conventional electron microscopic preparation. The search for lesions, often consisting of only a few cells in randomly obtained small specimen blocks, is time consuming and often without success. The methodological requirements for comparative enzyme cytochemical and morphological studies, i.e., preservation of both enzyme activity and ultrastructure, are divergent. By processing large native cryostat sections for electron microscopy, small preneoplastic focal lesions were successfully targeted in liver and kidney. Glucose-6-phosphatase, alkaline phosphatase, acid phosphatase, catalase, and cytochrome c oxidase activities were distinctly localized to endoplasmic reticulum, canalicular membrane, lysosomes, peroxisomes, and mitochondria, respectively, in the morphologically altered cells. Fixation of serial cryostat sections and enzyme reactions were both carried out through a semipermeable membrane except those for cytochrome c oxidase, which was demonstrated after fixation through the membrane by floating the section in incubation medium containing cytochrome c. Thereafter, the sections were flat embedded and polymerized between epoxy resin disks and aluminum dishes fitting exactly together. The objects of interest were identified in the light microscope, cut out, and reembedded in reversed gelatine capsules. By using this technique an ultrastructural preservation was achieved similar to that seen after immersion fixation. The enzyme activities were clearly localized without diffusion of the reaction product or unspecific deposits. The procedure permits precise targeting and complex studies of rare and small lesions, and opens new perspectives for the use of cryo-preserved tissue.