Is off-label thrombolysis safe and effective in a real-life primary stroke center? A retrospective analysis of data from a 5-year prospective database.

BACKGROUND: Intravenous thrombolysis (IVT) use for acute ischemic stroke (AIS) varies among countries, partly due to guidelines and product labeling changes. The study aim was to identify the characteristics of patients with AIS treated with off-label IVT and to determine its safety when performed in a primary stroke center (PSC). METHODS: This observational, single-center study included all consecutive patients admitted to Perpignan PSC for AIS and treated with IVT and patients transferred for EVT, between January 1, 2015 and December 31, 2019. Data of patients treated with IVT according to ("in-label group") or outside ("off-label") the initial guidelines and manufacturer's product specification were compared. Safety was assessed using symptomatic intracerebral hemorrhage (SIH) as the main adverse event. RESULTS: Among the 892 patients in the database (834 screened by MRI, 93.5%), 746 were treated by IVT: 185 (24.8%) "in-label" and 561 (75.2%) "off-label". In the "off-label" group, 316 (42.4% of the cohort) had a single criterion for "off-label" use, 197 (26.4%) had two, and 48 (6.4%) had three or more criteria, without any difference in IVT safety pattern among them. SIH rates were comparable between the "off-label" and "in-label" groups (2.7% vs. 1.1%, P=0.21); early neurological deterioration and systematic adverse event due to IVT treatment were similar in the 2 groups. "Off-label" patients had higher in-hospital (8.7% vs. 3.8%, P=0.05) and 3-month mortality rates (12.1% vs 5.4%, P<0.01), but this is explained by confounding factors as they were older (76 vs 67 years, P<0.0001) and more dependent (median modified Rankin scale score 0.4 vs 0.1, P<0.0001) at admission. CONCLUSIONS: "Off-label" thrombolysis for AIS seems to be safe and effective in the routine setting of a primary stroke center.

Endovascular treatment for acute ischemic stroke at a primary stroke center: First results of the Perpignan center.

INTRODUCTION: Converting a high-volume primary stroke center (PSC) into a stroke center that can perform emergency endovascular treatment (EVT) could reduce the time to thrombectomy. We report the first results of a newly established EVT facility at the Perpignan PSC and their comparison with the targets defined by the established guidelines. PATIENTS AND METHOD: For this comprehensive observational study, data of patients with acute ischemic stroke (AIS) due to proximal large vessel occlusion (LVO) and treated by EVT at the Perpignan PSC from December 5, 2019 to September 15, 2020 were extracted from an ongoing prospective database. RESULTS: During the study period, 37 patients underwent EVT at the Perpignan PSC. The median (range) symptom-onset to recanalization time was 262min (100-485min). The median (range) intra-hospital times were: 20min (2-58min) for door-to-imaging, 57min (30-155min) for imaging-to-puncture, 55min (15-180min) for puncture-to-recanalization, and 137min (59-319min) for door-to-recanalization. At 3 months post-AIS, the favorable outcome (modified Ranking Score: 0-2) rate was 50% and the mortality rate was 19.4%. These results are comparable to those of previous clinical trials, and meet the targets defined by the current consensus statements for EVT. DISCUSSION AND CONCLUSION: Our results show the feasibility and safety of EVT in a PSC for patients with AIS due to LVO. The implementation of this strategy may be important for shortening the time to thrombectomy.

Universal nonselective excitation and refocusing pulses with improved robustness to off-resonance for Magnetic Resonance Imaging at 7 Tesla with parallel transmission.

PURPOSE: In MRI at ultra-high field, the kT -point and spiral nonselective (SPINS) pulse design techniques can be advantageously combined with the parallel transmission (pTX) and universal pulse techniques to create uniform excitation in a calibration-free manner. However, in these approaches, pulse duration is typically increased as compared to standard hard pulses, and excitation quality in regions exhibiting large resonance frequency offsets often suffer. This limitation is inherent to structure of kT -point or SPINS pulse, and likely can be mitigated using parameterization-free pulse design approaches. METHODS: The Gradient Ascent Pulse Engineering (GRAPE) algorithm was used to design parameterization-free RF and magnetic field gradient (MFG) waveforms for creating 8∘ excitation, up to 105∘ scalable refocusing and inversion, nonselectively across the brain. Simulations were performed to provide flip angle normalized root-mean-squares error (FA-NRMSE) estimations for the 8∘ and the 180∘kT -point, SPINS, and GRAPE pulses. GRAPE pulses were tested experimentally with anatomical head scans at 7T. RESULTS: As compared to kT -points and SPINS, GRAPE provided substantial improvement of excitation, refocusing, and inversion quality at off-resonance while at least preserving the same global FA-NRMSE performance. As compared to kT -points, GRAPE allowed for a substantial reduction of the pulse duration for the 8∘ excitation and the 105∘ refocusing. CONCLUSIONS: Parameterization-free universal nonselective pTX-pulses were successfully computed using GRAPE. Performance gains as compared to kT -points were validated numerically and experimentally for three imaging protocols. In its current implementation, the computational burden of GRAPE limits its use to applications where pulse computations are not subject to time constraints.

Geometric Origin of the Tennis Racket Effect.

The tennis racket effect is a geometric phenomenon which occurs in a free rotation of a three-dimensional rigid body. In a complex phase space, we show that this effect originates from a pole of a Riemann surface and can be viewed as a result of the Picard-Lefschetz formula. We prove that a perfect twist of the racket is achieved in the limit of an ideal asymmetric object. We give upper and lower bounds to the twist defect for any rigid body, which reveals the robustness of the effect. A similar approach describes the Dzhanibekov effect in which a wing nut, spinning around its central axis, suddenly makes a half-turn flip around a perpendicular axis and the monster flip, an almost impossible skateboard trick.

Shear stress is associated with markers of plaque vulnerability and MMP-9 activity.

BACKGROUND: Vulnerable plaque has been associated with local macrophage accumulation and local high matrix metalloproteinase-2 (MMP-2) and MMP-9 activity. Since shear stress is a known local modulator of plaque location, we have determined whether local shear stress was associated with local plaque composition and with local MMP activity. METHODS AND RESULTS: In 17 NZW rabbits plaque was generated by denudation of the infrarenal aorta over a region of 5 cm and feeding them a high cholesterol diet for 2 months. After 2 months, a motorised IVUS pullback of the infrarenal aorta was performed with a 40 MHz IVUS catheter (CVIS, Boston Scientific, USA). IVUS derived vessel wall-lumen contours were reconstructed in 3D with in-house developed software. These reconstructions served as an input for a computational fluid dynamics technique, from which the 3-D shear stress field was calculated. Plaque regions were divided in 5 regions (n=8) to identify the location of highest macrophage accumulation or selected on basis of shear stress to identify whether high shear stress selects macrophage accumulation (n=8). In a second series, shear stress values were used to select regions -containing both latent and active MMP-2 and MMP-9. Segments were sectioned with a microtome and stained for smooth muscle cells (SMC), macrophages (MPhi) and collagen (COL). MPhi, displayed the highest density upstream of the plaque (6.9+/-2.4%, p<0.05), while SMC accumulated downstream (74.8+/-1.9%) of the plaque. High shear stress was associated with MPhi accumulation and MMP-9 activity (p<0.05). CONCLUSION: Upstream location of macrophages in plaques is associated with high shear stress and MMP-9 accumulation. These findings are discussed in relation to rheological theories reported previously in atherosclerosis.

Acceptability of COL-1492, a vaginal gel, among sex workers in one Asian and three African cities.

OBJECTIVES: To evaluate the acceptability of COL-1492, a vaginal gel containing 52.5 mg nonoxynol-9, in an HIV prevention trial. METHODS: Sex workers participating in a phase II/III triple blind, randomised trial in Benin, Côte d'Ivoire, South Africa, and Thailand were interviewed on the gel's acceptability at monthly scheduled clinic visits. Safer sex counselling, male condoms, and study gels were given at each monthly visit; a gynaecological examination and HIV test were performed. Phase III interviews considered the participants' appreciation of the gel. On the first, second, and fifth follow up visits, the study volunteers completed more extensive questionnaires. RESULTS: Responses were similar between treatment arms. Women indicated not liking their gel in 1.8% of the visits; 98.1% of the women found the gel easy to apply; 30.1% said that it affected sexual intercourse. These effects were mostly improvements (92.6%) by facilitating intercourse (73.6%). Intercourse was more often affected in women reporting painful sexual intercourse (OR: 2.59 (95% CI 1.63 to 4.12)) and in older women. The latter effect differed among centres. CONCLUSION: Most participants found their assigned gel acceptable and the vast majority of reported effects on intercourse were favourable. The type of gel had no significant impact on the findings.

Recommendations for the clinical development of topical microbicides: an update.

Topical microbicides are products that are being developed to prevent HIV infection and other sexually transmitted diseases (STD) through topical application to the genital and rectal epithelial surfaces. This paper is an update of the clinical section of a general guidance for the development and evaluation of microbicidal products that was first published by the International Working Group on Microbicides (IWGM) in 1996. (The preclinical section of that document will be updated separately later.) All topical microbicides should be clinically evaluated in humans for safety and effectiveness. Safety studies are necessary to evaluate the potential for systemic absorption and toxicity as well as local toxic effects, such as irritation, ulceration, burning, and itching. Reported symptoms of burning and itching are relevant to future product use and acceptability. Irritation and ulceration of the vaginal, cervical, penile, or rectal epithelium have the potential to result in an increased transmission of HIV and other STD. Effectiveness studies to assess the prevention of HIV infection or STD, depending upon the product indication, are subsequently conducted. These trials need to be large enough to detect clinically meaningful levels of protection. For spermicidal microbicides, additional contraceptive effectiveness studies are also needed.

Evaluation of the Roche Neisseria gonorrhoeae 16S rRNA PCR for confirmation of AMPLICOR PCR-positive samples and comparison of its diagnostic performance according to storage conditions and preparation of endocervical specimens.

The AMPLICOR PCR was used to detect Neisseria gonorrhoeae in endocervical specimens. A 16S rRNA PCR performed on N. gonorrhoeae-positive samples showed sensitivities of 73.2, 64.3, and 94.4% for samples treated directly with AMPLICOR lysis buffer, samples suspended in 2-sucrose phosphate, and samples suspended in diluted phosphate-buffered saline, respectively.

Detection of Chlamydia trachomatis and Neisseria gonorrhoeae by enzyme immunoassay, culture, and three nucleic acid amplification tests.

The purpose of this study was to evaluate and compare three commercially available nucleic acid amplification tests (NAATs) for the detection of Neisseria gonorrhoeae and Chlamydia trachomatis. Roche PCR and Becton Dickinson strand displacement amplification (SDA) were performed on 733 endocervical swab specimens from commercial sex workers. Abbott ligase chain reaction (LCR) was performed on a subset of 396 samples. Endocervical specimens from all women were also tested by culture for N. gonorrhoeae and by Syva MicroTrak enzyme immunoassay (EIA) for C. trachomatis. A positive N. gonorrhoeae result was defined as a positive result by culture or by two NAATs, and a positive C. trachomatis result was defined as a positive result by two tests. According to these definitions, the sensitivities and specificities for the subsample of 396 specimens of N. gonorrhoeae culture, PCR, SDA, and LCR were 69.8, 95.2, 88.9, and 88.9% and 100, 99.4, 100, and 99.1%, respectively; the sensitivities and specificities of C. trachomatis EIA, PCR, SDA, and LCR were 42.0, 98.0, 94.0, and 90.0% and 100, 98.0, 100, and 98.6%, respectively. The performance characteristics of N. gonorrhoeae culture, PCR, and SDA and C. trachomatis EIA, PCR, and SDA for all 733 specimens were defined without inclusion of LCR results and by discrepant analysis after resolution of discordant N. gonorrhoeae PCR results and of discordant C. trachomatis EIA and PCR results by LCR testing. The sensitivities of N. gonorrhoeae culture, PCR, and SDA before and after LCR resolution were 67.8, 95.7, and 93.9% and 65, 95.8, and 90.0%, respectively. The sensitivities of C. trachomatis EIA, PCR, and SDA decreased from 39.4, 100, and 100% to 38.7, 98.7, and 94.7%, respectively. All three NAATs proved to be superior to N. gonorrhoeae culture and to C. trachomatis EIA. The accuracies of the different NAATs were quite similar. SDA was the only amplification assay with 100% specificity for detection of both N. gonorrhoeae and C. trachomatis in endocervical specimens.

Clinical research with topical microbicides as a potential HIV prevention method.

An overview of the different phases in microbicide research is given with special attention to nonoxynol-9, the only ingredient that has been tested in phase III trials so far. The methodological and ethical challenges in conducting phase III studies are described. These include study population, compliance data, standardization, therapy for HIV-positive women, and informed consent. Despite these challenges, phase III trials are feasible and should be initiated now.

A phase I study of a novel potential intravaginal microbicide, PRO 2000, in healthy sexually inactive women.

BACKGROUND: Although the male condom provides a reliable means of preventing HIV transmission, a broader choice of methods is required particularly in circumstances where the negotiation of condom use is difficult. Development of new products that may be effective as topical vaginal microbicides is the focus of a great deal of research activity currently. The novel agent PRO 2000, a naphthalene sulphonate derivative with in vitro activity against HIV and other sexually transmissible pathogens, is one such compound. We have studied the local and systemic safety and tolerance of a vaginal gel formulation of this agent at two concentrations (0.5% and 4%) over a 2 week period of daily exposure in two cohorts of healthy sexually abstinent women (one in London, UK, and the other in Antwerp, Belgium). METHODS: This was a randomised, placebo controlled, double blind, three arm clinical trial conducted on two sites. Macroscopic evidence of genital epithelial changes was sought using colposcopy and evidence of microscopic inflammation was acquired using high vaginal biopsy from predetermined sites (UK cohort only). Blood levels of PRO 2000 were measured and laboratory safety tests, including coagulation screens, were performed. The impact on vaginal ecology was also assessed. RESULTS: 73 women were enrolled across both sites (36 UK, 37 Belgium); 24, 24, 25 in the 4%, 0.5%, and placebo groups respectively. Of these, 70 completed 2 weeks' exposure to the study gel. Three (all in the 4% group) withdrew owing to adverse events which were possibly or probably gel related. Cervicovaginal abrasion was seen colposcopically in three subjects after 14 days of gel use (two in the 4% group and one in the placebo group). Genital ulceration was not seen during gel use in any of the subjects who completed the study. Histological evaluation of vaginal biopsy samples (36 women only) showed evidence of increased inflammatory signs in one participant of the 4.0% group. One volunteer in the placebo group had moderate inflammation at screening and at follow up. Severe inflammation was not seen among any of the subjects tested. Plasma levels of PRO 2000 and laboratory safety tests showed no evidence of systemic absorption. No impact was seen on normal vaginal ecology in the UK cohort where samples were taken 12 hours after the last gel application. CONCLUSION: In this phase I study PRO 2000 gel was found to be generally well tolerated with promising local and systemic safety profiles. The 0.5% gel was better tolerated than the 4% gel as fewer genital epithelial adverse events were seen in the former. Phase II studies are about to begin in sexually active women.

In vitro susceptibility of Enterococcus faecium isolated from food to growth-promoting and therapeutic antibiotics.

A total of 76 E. faecium strains, isolated at retail level from raw poultry meat, cheese, raw pork, and preparations of cheese and raw pork, were tested for their susceptibility and resistance to growth-promoting antibacterials used in animals and antibiotics used therapeutically in humans. All strains were uniformly susceptible to the growth promoters bambermycin and avilamycin. Resistance against bacitracin, virginiamycin and narasin was high among strains from poultry meat. With tylosin, a macrolide antibiotic used therapeutically and for growth promotion, resistance was mainly detected in strains originating from poultry meat, though also in some strains from pork and from pork and cheese preparations. The therapeutic antibiotic dalfopristin/quinupristin did not show full cross-resistance with the growth-promoting antibiotic virginiamycin. With dalfopristin/quinupristin two different levels of resistance were found. Only one E. faecium strain isolated from poultry was resistant to the glycopeptides avoparcin and vancomycin. Only one poultry meat strain was highly resistant to ampicillin. However, nearly all poultry meat strains showed decreased sensitivity. Only 3 out of 24 poultry strains were susceptible to minocycline, while all strains from other origins were susceptible to this tetracycline antibiotic. High-level streptomycin resistance was seen in strains of all origins, though infrequently. High-level gentamicin resistance was not found.

Safety of multiple daily applications of COL-1492, a nonoxynol-9 vaginal gel, among female sex workers. COL-1492 Phase II Study Group.

RATIONALE: COL-1492 is a nonoxynol-9 (N-9)-containing vaginal gel and may be a potential microbicide. As part of an effectiveness trial, an initial toxicity study was conducted. OBJECTIVES: The main objective of the reported study was the assessment of the toxicity of a 52.5 mg N-9 gel, COL-1492, when used a number of times each day by female sex workers. METHODS: This was a randomized, placebo-controlled triple-blinded trial among female sex workers. The participants were asked to use the product for each vaginal sexual act. At each monthly visit a gynaecological examination with sexually transmitted disease sampling and colposcopy was performed. Venous blood was drawn for syphilis and HIV serology. All women received intensive counselling on condom use. Male condoms and sexually transmitted disease treatment were given free of charge. RESULTS: Only blinded results on the colposcopic examinations are reported. The incidence of lesions with or without an epithelial disruption was low: 0.06 and 0.29, respectively, per 100 woman-days in group A; 0.09 and 0.26 respectively per 100 woman-days in group B. There was no significant difference between the two arms. CONCLUSION: The multiple daily use of COL-1492 by female sex workers did not show an increase of local toxicity over that of a placebo. Colposcopy was discontinued in the autumn of 1997 in accordance with a Data Safety Monitoring Board decision. In the currently ongoing effectiveness trial the assessment of the product's toxicity continues to be monitored by simple visual examination.

Challenges in the conduct of vaginal microbicide effectiveness trials in the developing world.

Conducting a phase III trial of a vaginal microbicide in a developing country poses several important and complex ethical challenges. As part of a process to bridge the gap between ethical theory and practice, we share our experiences in performing a phase III trial of Col 1492 (Advantage S) among female sex workers at four sites world-wide; Durban, Abidjan, Cotonou and Hat Yai. The ethical challenges included: (i) difficulties in obtaining informed consent. Participants were unable to grasp the concepts of a clinical trial for several weeks to months. In Cotonou, 30% of the women did not know the gel was tested for HIV prevention. Only 25% understood what a placebo was. In Durban, 70% of the women did not fully understand the study after 3 months; (ii) in sustaining the use of known HIV prevention strategies. Participants at the Durban site had difficulty in sustaining condom use due to financial and client preferences. Sex without condoms was worth more ($20) than sex with condoms ($10); (iii) in maintaining the confidentiality of the subject's HIV status. Novel approaches such as role plays and emphasis on other exclusion criteria were needed to maintain the confidentiality of women not included in the trial due to their HIV status; (iv) in providing care and support to the subjects who became infected with HIV during the trial. Women could only be offered routine sexually transmitted disease treatment and counselling. Anti-retrovirals were not offered. The successes and failures of the solutions attempted are described.

Preclinical studies on thiocarboxanilide UC-781 as a virucidal agent.

BACKGROUND: Thiocarboxanilide UC-781 is a highly potent and selective non-nucleoside reverse transcriptase inhibitor (NNRTI) of HIV-1, which also has virucidal properties. Recent studies have shown that UC-781 would seem an ideal candidate for application as a vaginal virucide. OBJECTIVE: To investigate the antiviral potency and stability of UC-781 in a lipophilic gel formulation. METHODS: UC-781 was formulated in replens gel at different concentrations and administered intravaginally to rabbits at 5% in replens gel for 10 days. UC-781 was also exposed to temperatures of 4, 37 and 50 degrees C, and to low pH (6.0, 4.3, 2.0 and 1.2). A number of microorganisms were exposed in culture to serial dilutions of UC-781. RESULTS: The drug was stable under low pH conditions and did not lose its antiviral potency upon 4 h exposure to pH 3.5 (the estimated vaginal pH). UC-781 can be easily formulated into a lipophilic gel (replens; up to 5%) and proved fully stable at 50 degrees C for 30 days. There was no effect on the growth of microorganisms (i.e., Candida and Lactobacillus strains) that are present in the vaginal flora. Neither systemic side-effects, nor local inflammation or damage of the vaginal mucosa or epithelium were observed in rabbits to which 5% UC-781 in replens gel had been administered. UC-781, formulated as 0.5, 0.2 and 0.05% replens gel, and UC-38, alpha-APA and zidovudine, formulated as 0.5 or 0.2% replens gel, were effective in protecting CEM cells in the very beginning against productive HIV-1 replication. This points to an efficient diffusion of the drugs from the lipophilic gel to the hydrophilic culture medium. However, subsequent subcultivations at a dilution rate of 1:10 every 3-4 days resulted in a rapid breakthrough of virus with all drugs except UC-781 in its 0.5 and 0.2% gel formulation. These cultures were fully protected against HIV-1 and remained completely cleared from virus for at least 10 subcultivations. CONCLUSIONS: The virus that emerged under 0.05% UC-781 remained highly sensitive to the NNRTI, including UC-781, in cell culture, suggesting a lack of resistance development under our experimental conditions.

Safety evaluation of nonoxynol-9 gel in women at low risk of HIV infection.

OBJECTIVE: To determine the safety of a vaginal microbicide, COL-1492, containing 52.5 mg nonoxynol-9, applied once daily for 14 days among healthy volunteers. METHODS: A randomized, double-blind controlled trial with three arms, COL-1492 gel versus placebo gel versus no-treatment controls, was conducted. Outcomes of interest were reported genital symptoms, incidence of gynaecological signs, and incidence of genital lesions revealed by colposcopy. Participants were enrolled in four centres (Belgium, The Netherlands, and two in Thailand). RESULTS: A total of 534 women participated in the study: 179 used COL-1492, 178 used placebo, and 177 were no-treatment controls. Study visits were scheduled 1 week prior to enrollment (day -7), day 0 (enrollment), day 8 and day 14. The most frequently reported genital symptom was vaginal discharge in both the COL-1492 and placebo groups. This appeared to be related to leakage of the product out of the vagina. The incidence of lesions associated with epithelial disruption (ulcers and abrasions) was very low (< 2%) and there was no statistically significant difference between the three groups. Of the lesions observed by colposcopy that did not involve epithelial disruption, petechial haemorrhage was the most frequently detected, with an incidence of 20.1, 9.0 and 7.3% in the COL-1492, placebo and control groups, respectively. COL-1492 users had a higher incidence of erythema (8.4 versus 2% in the other groups). CONCLUSION: COL-1492 showed minimal toxicity when applied once daily. A Phase III trial to assess the product's effectiveness in HIV prevention is currently ongoing.

Virulence factors of verocytotoxin-producing Escherichia coli isolated from raw meats.

PCR for verocytotoxin-producing Escherichia coli (VTEC) was positive in 4.6% of 2,440 raw meat samples; only beef, sheep, and venison samples were positive. None of the isolated VTEC strains belonged to serogroup O157. Additional virulence factors were detected in only a minority of strains, suggesting that most of these meat VTEC isolates are not pathogenic.