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PubMed2026

Ten years on, still out of reach: barriers to PrEP access and retention in France according to frontline actors (QualiPrEP Study).

Pre-exposure prophylaxis (PrEP) for HIV has been available in France since 2014, and reimbursed since 2016, with general practitioners allowed to prescribe it since 2021. Despite these policy advances, uptake remains low among some of the most affected populations. This community-based qualitative study explored barriers to PrEP access and retention ten years into its implementation.Interviews were conducted with 28 PrEP frontline actors (healthcare professionals and community-based workers involved in promoting, prescribing, or supporting PrEP). The sample included one group discussion (n = 5), two triads (n = 6), two dyads (n = 4), and nine individual interviews (n = 13). Thematic analysis was inductive, with barriers classified across four main domains.Participants were mostly cisgender men, median age 48, born in France and abroad, and employed by NGOs in Paris. Thirteen barriers and four major themes emerged: (1) Internal psychosocial barriers: lack of knowledge, negative health-related reactions; HIV stigma; STI risk perception, taboos; (2) Internal pragmatic barriers: perceived limits of protection, usage and follow-up constraints; (3) External psychosocial barriers: limited physician knowledge and reluctance; (4) External pragmatic barriers: communication failures; structural constraints, lack of human and financial resources.Findings call for more targeted messaging, simplified care models and provider training. They highlight the need to address social and symbolic dimensions of PrEP, with insights from those supporting users to ensure more equitable implementation.

Humans↗

PubMed1999

Hepatic enhancement analysis in children using smart prep monitoring for 2 : 1 pitch helical scanning.

PURPOSE: To analyze hepatic enhancement by using Smart Prep protocols appropriate for children of different weight groups and 2:1 pitch helical CT imaging as the investigative tools. PATIENTS AND METHODS: A group of 55 children ranging in weight between 20 and 180 lbs underwent 67 contrast-enhanced abdominal helical CT examinations using Smart Prep (GE Medical Systems, Milwaukee, Wisc.). Of these studies, 21 (31 %) were excluded because of failure to follow the prescribed Smart Prep protocols. Smart Prep protocols were established for nine different weight groups. Scan delay, aorta and liver time to peak, and liver enhancement over baseline were recorded. RESULTS: Optimal abdominal CT studies with adequate contrast enhancement of hepatic and portal veins were obtained in 46 patients. There was no significant difference in the time between peak aortic and the liver enhancement among different weight groups (mean time 12.0 +/- 7.1 s for all children). However, the mean hepatic enhancement over baseline in children weighing < 30 lbs was below 50 Hounsfield units (HU) compared to the rest of the children who had mean hepatic enhancement of > 50 HU. CONCLUSION: Two-thirds of the Smart Prep protocols were successfully implemented, and all of these resulted in good contrast enhancement of hepatic and portal veins. Optimal mean liver enhancement (> 50 HU) was seen in children >/= 30 lbs. Children < 30 lbs had mean liver enhancement of 33 HU +/- 7.2 above the baseline likely caused by contrast dose.

Adolescent↗

PubMed2026

The Long Road to Long-Acting: What Oral PrEP and CAB-LA Teach Us About Scaling Lenacapavir.

Despite significant biomedical advances, human immunodeficiency virus (HIV) remains a persistent global health crisis, with over 40 million people affected as of 2023, two-thirds of whom live in the World Health Organization (WHO) African Region. However, from an HIV prevention perspective, the more urgent concern is the continued occurrence of approximately 1.3 million new infections annually, particularly in sub-Saharan Africa and in settings where incidence is stable or increasing. This commentary explores the evolving landscape of HIV prevention, focusing on the trajectory of oral pre-exposure prophylaxis (PrEP), long-acting injectable cabotegravir (CAB-LA), and the newly emerging lenacapavir. While oral PrEP opened new possibilities, adherence challenges have limited its impact. CAB-LA demonstrated superior efficacy but encountered access, cost, and delivery barriers that restricted uptake. Lenacapavir, offering 6-monthly subcutaneous dosing with ≥ 99.9% efficacy in trials, holds the potential to overcome these hurdles. As of May 2026, lenacapavir had received regulatory approval in 17 countries, including several African nations, while regulatory reviews remained ongoing in multiple additional countries, reflecting the rapid global expansion of access to this long-acting HIV prevention option. However, its success depends on clinical promise, timely licensing, affordability, and integration into health systems. Drawing from real-world lessons of oral PrEP and CAB-LA, this paper argues that a proactive, coordinated rollout of lenacapavir could dramatically expand prevention reach. With global stakeholders aiming for 3 million users by 2028 and strategic licensing in 120 countries, the groundwork is in place. The recent release of WHO guidance recommending lenacapavir as an additional PrEP option further strengthens this momentum. Yet, equitable delivery, user-centred models, and strong policy backing will be critical. Ultimately, long-acting PrEP is not just a clinical breakthrough; it is a test of health systems' ability to deliver innovation at scale.

Humans↗

PubMed2001

Effects of sodium hypochlorite and RC-prep on bond strengths of resin cement to endodontic surfaces.

There is concern that the use of sodium hypochlorite (NaOCl) and RC-Prep may lower the bond strength of resin cements. The objective of this study was to evaluate the effect of 5% NaOCl and RC-Prep treatment on the bond strength of a resin cement, C&B Metabond. Control roots (group 1) were biomechanically prepared using 0.9% NaCl as an irrigant; group 2, roots with 5% NaOCl; group 3, roots with RC-Prep; group 4, roots with 0.9% NaCl followed by 10% ascorbic acid; group 5, roots with 5% NaOCl followed by 10% ascorbic acid (pH 4); group 6, roots with 5% NaOCl followed by 10% neutral sodium ascorbate; and group 7, roots with RC-Prep followed by 10% ascorbic acid. All roots were then filled with C&B Metabond, incubated in water for 24 h, and then cross-sectioned into six 1-mm thick slabs representing cervical and middle root dentin. The slabs were trimmed and tested for tensile bond strength. The results demonstrated that both 5% NaOCl and RC-Prep produced significantly (p < 0.05) large reductions in resin-dentin bond strengths, and the reductions could be completely reversed by the application of either 10% ascorbic acid or 10% sodium ascorbate.

Analysis of Variance↗

PubMedDate not supplied

Semiautomated monolayer preparation of bronchial secretions using AutoCyte PREP.

OBJECTIVE: Development of a method for semiautomated preparation of purified, representative and conventionally stained monolayer smears from bronchial secretions suitable for subjective and/or automated cytodiagnosis. STUDY DESIGN: Bronchial secretions from 50 patients with and 48 without carcinoma cells of different types were collected in Saccomanno's fixative. After routine pick-and-smear processing, residual material was subjected to a mucolytic agent (ammonium thioglycolate). Separation of cells was performed by differential centrifugation through aqueous sucrose. The pellet was automatically processed by the AutoCyte PREP system. RESULTS: Slides revealed well-preserved, slightly shrunken, homogeneously distributed cells devoid of mucus, cellular debris and bacteria in monolayer arrangement nearly without overlap. Granulocytes were eliminated to a large extent. Comparison with pick-and-smear specimens showed more tumor cells per square centimeter of slide surface in 100% of AutoCyte PREP slides. The number of tumor cells per AutoCyte PREP slide was higher in 46% and lower in 54%. Selecting slides at random and requiring at least 10 abnormal cells to establish a tumor diagnosis were achieved in 82.7% if only one, in 88.0% if two and 94.0% if seven or eight AutoCyte PREP slides were investigated. CONCLUSION: The semiautomated method yielded conventionally stained, purified monolayer smears from bronchial secretions with cellular morphology suitable for evaluation by cytologists and screening machines. Representativity of AutoCyte PREP monolayers was superior to that of pick-and-smear slides.

Adenocarcinoma↗

PubMedDate not supplied

Direct-to-vial use of the AutoCyte PREP liquid-based preparation for cervical-vaginal specimens in three European laboratories.

OBJECTIVE: To compare the AutoCyte PREP direct-to-vial procedure to the conventional Pap smear in two large and similar patient groups compiled from the testing experience of three cytology laboratories in Switzerland and France. STUDY DESIGN: Randomly selected, large patient groups were evaluated using either the conventional Pap smear or the AutoCyte PREP direct-to-vial liquid-based preparation. Results were then compared statistically as to disease detection and sample adequacy. RESULTS: Specimen adequacy was greatly improved in the group tested with the AutoCyte PREP. PREP also demonstrated a significant reduction in ASCUS and ASCUS:LSIL+ ratios. The three laboratories participating in this review found significantly improved detection of both low and high grade SIL. Routine use of AutoCyte PREP for cervical cytology screening offers substantial improvements in adequacy and disease detection.

Cytological Techniques↗

PubMed2000

Preliminary assessment of the AutoCyte PREP. Direct-to-vial performance.

OBJECTIVE: To compare the sensitivity for squamous intraepithelial lesions (SILs) using AutoCyte PREP (TriPath Imaging, Burlington, North Carolina) thin-layer slides with the sensitivity for using conventional Pap smears. STUDY DESIGN: Results for 10,367 cases for the period January 1, 1999, through April 15, 1999, using conventional Pap smears were compared to results of 2,231 cases evaluated using AutoCyte PREP thin-layer slides for the same period in 2000. Biopsy follow-up data were reviewed when available. RESULTS: The overall quality of cellular presentation was much improved using AutoCyte PREP. The number of unsatisfactory and "satisfactory but limited by" (SBLB) cases was significantly reduced as compared with that in the population evaluated using conventional Pap smears. Evaluation of AutoCyte PREP slides also yielded a significant improvement in the detection of SILs. Biopsy follow-up confirmed the specificity of the results. CONCLUSION: In routine use, AutoCyte PREP is both practical and significantly more effective in the detection of SIL as compared with conventional Pap smears. The significantly improved reduction of unsatisfactory and SBLB cases and increased detection of disease confirm earlier publications of results using a manual preparation method.

Biopsy↗

PubMed2006

The effects of sodium hypochlorite (5.25%), Chlorhexidine (2%), and Glyde File Prep on the bond strength of MTA-dentin.

The purpose of this study was to evaluate the effects of sodium hypochlorite (5.25%), chlorhexidine (2%), and Glyde File Prep on the bond strengths of MTA-dentin in vitro. Standardized dentin disks were prepared and the central hole in each disk was filled with mineral trioxide aggregate (MTA). The specimens were randomly divided into four groups to be immersed in saline, 5.25% NaOCl, 2% chlorhexidine, and Glyde File Prep for 2 hours. The bond strengths of MTA-dentin were measured with a material testing system (MTS) and the fractured surfaces on the root walls were observed by scanning electron microscopy. Compared with the control group, the bond strengths were significantly lower in Glyde File Prep group (p < 0.05) and there was no significant difference in the chlorhexidine group or in the NaOCl group (p > 0.05). This study suggested that Glyde File Prep could negatively affect the bond strengths of MTA-dentin.

Aluminum Compounds↗

PubMed1989

Efficient endotoxin removal with a new sanitizable affinity column: Affi-Prep Polymyxin.

A new affinity column packing for removal of endotoxins has been prepared by coupling USP drug-quality polymyxin B to Affi-Prep, a novel synthetic macroporous polymer. Affi-Prep Polymyxin binds endotoxins from a number of different strains of gram-negative bacteria. Endotoxin binding is not significantly affected by 10 mg/ml of bovine serum albumin or human immunoglobulin G, by 1 mg/ml sodium dodecyl sulphate, or by 1 mg/ml deoxycholate. Affi-Prep Polymyxin is stable to treatment with 1.0 M sodium hydroxide, an important property for sanitizing the resin. The resin shows a high ligand stability, since no leakage of polymyxin B from the packing could be detected. Affi-Prep Polymyxin exhibited the highest endotoxin binding efficiency when compared with several commercial agarose affinity packings.

Chromatography, Affinity↗

PubMed1995

Aortoiliac segment examination with colour flow Duplex--a pilot study using Klean Prep. to improve the image quality.

OBJECTIVES: Currently colour flow Duplex examination of the iliac arteries is at best 84-92% sensitive. In an attempt to find a technique to improve on this sensitivity we have studied the effect of Klean Prep, an iso-osmotic bowel preparation, on the Duplex image and Doppler signal obtained when scanning iliac arteries. METHODS: Twenty iliac segments in 10 arteriopaths were scanned by a blinded observer, after either starving for 12 h or having Klean Prep bowel preparation. Grey scale image, colour mapping and Doppler signal to noise ratios were scored on a linear analogue system. Each patient was subsequently rescanned after the other method of preparation and was once again scored by a blinded observer. The two sets of scores were then compared. RESULTS: We found significant improvements in the linear analogue scoring of grey scale images, colour mapping and Doppler signal to noise ratios, when using Klean Prep as opposed to starving the patient prescan. CONCLUSIONS: Preparing patients with Klean Prep before iliac Duplex examination improves the visualisation of these arteries.

Aorta, Abdominal↗

PubMed2004

Preliminary investigation of the advertising and availability of PREPs, the new "safe" tobacco products.

The tobacco industry recently introduced a new set of "safe" cigarettes and nicotine delivery devices that purportedly entail reduced tobacco-related disease risk due to their lower level of some carcinogens and toxins. Little is know about the biological impact of these potential reduced exposure products (PREPs) and nothing is known about their advertising and availability. Hence, two pilot studies were conducted to examine the latter issues for the first time. In Study 1, we examined tobacco ads in 10 popular magazines 1998--2002 and found that only 1% of ads were for PREPs. In Study 2, we attempted to purchase PREPs in a random sample of 113 small stores and found that only 4.4% sold any PREP. These preliminary findings tentatively suggest that the industry might not yet be heavily invested in products that have the potential to increase tobacco use by decreasing its perceived harm. Studies with larger samples are recommended.

Advertising↗

PubMed2003

Light and scanning electron microscopic evaluation of Glyde File Prep in smear layer removal.

AIM: To evaluate the effectiveness of Glyde File Prep used in conjunction with sodium hypochlorite irrigation in the removal of smear layer produced during root canal instrumentation. METHODOLOGY: Thirty-nine extracted human teeth with single root canals were used. Access cavities were prepared and the teeth divided into three groups of 13 teeth each. Each group was treated by one of the three different regimes of irrigation and conditioning during root canal instrumentation. Group A: 0.5 mL of 1% NaOCl irrigation after each file size with an additional final irrigation of 10 mL 1% NaOCl; group B: 0.5 mL of 1% NaOCl irrigation after each file size with an additional final irrigation of 10 mL 17% EDTA; group C: Glyde File Prep coated on each instrumentation file used in conjunction with 0.5 mL 1% NaOCl irrigation after each file size and an additional final irrigation of 10 mL 1% NaOCl. The teeth were then longitudinally grooved and sectioned. Root canal cleanliness was evaluated with the aid of a Nikon light microscope (x40 and x100) and scanning electron microscope (x1000 and x3000). The debris scores obtained at three canal regions were compared statistically within the same group and among different groups using repeated measurements of analysis of variance (anova) with Bonferroni adjustments and anova with posthoc Tukey HSD, respectively. RESULTS: The canals treated with EDTA and Glyde File Prep were significantly cleaner than those treated with NaOCl alone. The apical region of the root canals generally displayed more residual smear layer, but the difference was not significant. CONCLUSIONS: Used in conjunction with NaOCl irrigation, Glyde File Prep was effective in removing smear layer produced during root canal instrumentation.

Analysis of Variance↗

PubMed1996

Barium enema preparation: a study of low-residue diet, "Picolax' and 'Kleen-Prep'.

A prospective, randomized three-arm trial is presented of 150 consecutive patients attending for double-contrast barium enema (BE). This compares 'Picolax' (a combined stimulant and osmotic agent), 'Picolax' following a 3 day low-residue diet and 'Kleen-Prep' (a polyethylene-glycol osmotic agent). Faecal clearance, mucosal coating and colon fluid were scored in four colonic segments by two radiologists working independently and blinded to the preparation used. Analyses of an elderly subgroup and of side effects was performed. Low-residue diet conferred no benefit to Picolax preparation, which was satisfactory (ability to exclude 5 mm polyps) in 80% of patients. Kleen-Prep failed to achieve adequate preparation in 46%, due to excess fluid and poor mucosal coating. Kleen-Prep caused more patient nausea, abdominal bloating and pain than Picolax. Patients 70 years and older had similar results. Low-residue diet need not be used in addition to Picolax. Kleen-Prep as a single agent is not recommended for BE preparation.

Aged↗

PubMed2002

Equipping couples with the tools to cope with predictable and unpredictable crisis events: the PREP Program.

The current article focuses on the application of crisis intervention principles to primary prevention programs for marital distress. The Prevention and Relationship Enhancement Program (PREP) is a universal, empirically-supported preventative intervention program that teaches couples skills that decrease relationship risk factors and increase protective factors. These skills, mainly conflict resolution and communication skills, serve to protect relationships from the negative impact of both normative transitional crises (e.g., marriage) and other non-predictive crises. PREP emphasizes the development and maintenance of intimacy, commitment, and friendship in the relationship, which not only protects couples from the negative ramifications of crisis events, but may also decrease the chance of such crises happening in the first place. Research has shown that PREP significantly decreases multiple indicators of marital distress as much as four years after participation in the program in both clinical and community settings. PREP has also been shown to increase marital satisfaction.

Adaptation, Psychological↗

PubMed1999

Use of the Thin Prep Pap Test in clinical practice.

The Thin Prep Pap Test (Cytyc Corp., Boxborough, MA) received approval by the Food and Drug Administration in May 1996 as an alternative to the traditional conventional smear. The present direct-to-vial study assessed the utility of thin-layer technology for cervicovaginal screening in clinical practice. From May 1997-February 1998 (10 mo), 15,006 cervical smears were processed and evaluated; of these, 5,423 (36.1%) were conventional smears (CS) and 9,583 (63.9%) were Thin Prep slides (TP). Both methods were analyzed to compare specimen adequacy and detection rates of cervical lesions. The TP method reduced the "satisfactory but limited by" rate by 97% and the unsatisfactory rate by 63%. For low-grade squamous intraepithelial lesions (LSILs), TP slides yielded 3.6% (348/9,583) as compared to 0.98% (53/5,423) for CS, an increase of 267%. The TP method detected a threefold increase in the number of high-grade squamous intraepithelial lesions (HSILs) of 1.0% (100/9,583), as compared to 0.3% (17/5,425) for the CS group. The atypical squamous cells of undetermined significance/squamous intraepithelial lesion (ASCUS SIL) ratio was reduced by 54% in the TP group. In routine usage in our laboratory, the Thin Prep Pap Test yielded a significant increase in the detection of LSILs and HSILs as compared to conventional smears. Specimen adequacy was significantly improved.

Evaluation Studies as Topic↗

PubMed2026

Faster N1 latency in response to homeostatic-like plasticity of PREPs is impaired during pain: A randomized-placebo capsaicin-pain study.

INTRODUCTION: Homeostatic-like plasticity (HP-like) stabilizes cortical excitability through long-term potentiation and depression-like mechanisms. The efficacy of homeostatic regulation in the corticomotor system is impaired during pain, which may have functional relevance for chronic pain. This study investigated whether a cortical HP-like response could be assessed by nociceptive stimulation, and if such response was impaired by experimental tonic pain. METHODS: Twenty-eight healthy participants completed placebo and capsaicin sessions, with 11 sham controls for time and design. HP-like plasticity was induced with two blocks of anodal tDCS over the primary motor cortex. The N1 (TP7) and N2P2 (Cz) components of electrically induced pain-related evoked potentials (PREPs) were assessed from the volar forearm before and after patch application, and again immediately and 20 min after HP-like induction. An HP-like response was defined by PREP decrease after induction, and further normalization to baseline. RESULTS: Anodal tDCS did not induce an HP-like regulation of PREP amplitudes. Interestingly, an HP-like response was observed as a fastening of N1 latency after HP-like induction, which returned to baseline values after 20 min. The latter effect was impaired during capsaicin-induced pain, where N1 was slower. The N2P2 component showed habituation over time in all sessions. CONCLUSION: This is the first study that investigates the HP-like regulation of nociceptive-evoked responses. An HP-like response was observed as a shortening of N1 latency, suggesting that early nociceptive processing may be susceptible to homeostatic regulation. In contrast, the later component, N2P2, showed habituation over time, which prevented evaluation of HP-like effects.

Humans↗

PubMed1981

A randomised trial to investigate X-prep, oral mannitol and colonic washout for double-contrast barium enema.

Three methods of bowel preparation used prior to double contrast barium enemas were compared by a randomised trial in 60 patients. Evaluation was by radiological review and from a patient questionnaire. The preparations included X-Prep liquid with colonic washout, oral mannitol alone and oral mannitol with colonic washout. Adequacy of preparation as judged by faecal residue was significantly better after X-Prep than in either group receiving mannitol. The more severe purgation with mannitol did not result in better clearance of the large bowel and the addition of a colonic washout to mannitol did not reduce faecal residue. Side-effects and adverse comments were more common after mannitol. Diarrhoea was significantly less after X-Prep than after mannitol.

Anthraquinones↗

PubMed2006

Degradation of the amyloid beta-protein by the novel mitochondrial peptidasome, PreP.

Recently we have identified the novel mitochondrial peptidase responsible for degrading presequences and other short unstructured peptides in mitochondria, the presequence peptidase, which we named PreP peptidasome. In the present study we have identified and characterized the human PreP homologue, hPreP, in brain mitochondria, and we show its capacity to degrade the amyloid beta-protein (Abeta). PreP belongs to the pitrilysin oligopeptidase family M16C containing an inverted zinc-binding motif. We show that hPreP is localized to the mitochondrial matrix. In situ immuno-inactivation studies in human brain mitochondria using anti-hPreP antibodies showed complete inhibition of proteolytic activity against Abeta. We have cloned, overexpressed, and purified recombinant hPreP and its mutant with catalytic base Glu(78) in the inverted zinc-binding motif replaced by Gln. In vitro studies using recombinant hPreP and liquid chromatography nanospray tandem mass spectrometry revealed novel cleavage specificities against Abeta-(1-42), Abeta-(1-40), and Abeta Arctic, a protein that causes increased protofibril formation an early onset familial variant of Alzheimer disease. In contrast to insulin degrading enzyme, which is a functional analogue of hPreP, hPreP does not degrade insulin but does degrade insulin B-chain. Molecular modeling of hPreP based on the crystal structure at 2.1 A resolution of AtPreP allowed us to identify Cys(90) and Cys(527) that form disulfide bridges under oxidized conditions and might be involved in redox regulation of the enzyme. Degradation of the mitochondrial Abeta by hPreP may potentially be of importance in the pathology of Alzheimer disease.

Aged↗