Elucidating the role of water in collagen self-assembly by isotopically modulating collagen hydration.

Water is known to play an important role in collagen self-assembly, but it is still largely unclear how water-collagen interactions influence the assembly process and determine the fibril network properties. Here, we use the H[Formula: see text]O/D[Formula: see text]O isotope effect on the hydrogen-bond strength in water to investigate the role of hydration in collagen self-assembly. We dissolve collagen in H[Formula: see text]O and D[Formula: see text]O and compare the growth kinetics and the structure of the collagen assemblies formed in these water isotopomers. Surprisingly, collagen assembly occurs ten times faster in D[Formula: see text]O than in H[Formula: see text]O, and collagen in D[Formula: see text]O self-assembles into much thinner fibrils, that form a more inhomogeneous and softer network, with a fourfold reduction in elastic modulus when compared to H[Formula: see text]O. Combining spectroscopic measurements with atomistic simulations, we show that collagen in D[Formula: see text]O is less hydrated than in H[Formula: see text]O. This partial dehydration lowers the enthalpic penalty for water removal and reorganization at the collagen-water interface, increasing the self-assembly rate and the number of nucleation centers, leading to thinner fibrils and a softer network. Coarse-grained simulations show that the acceleration in the initial nucleation rate can be reproduced by the enhancement of electrostatic interactions. These results show that water acts as a mediator between collagen monomers, by modulating their interactions so as to optimize the assembly process and, thus, the final network properties. We believe that isotopically modulating the hydration of proteins can be a valuable method to investigate the role of water in protein structural dynamics and protein self-assembly.

Trigeminal Nerve Repair: Is the Trigeminocardiac Reflex a Concern?

PURPOSE: Our hypothesis is that direct manipulation of the third and second divisions of the trigeminal nerve during microneurosurgery does not affect the incidence of trigeminocardiac reflex (TCR). The purpose of this paper was to analyze the incidence of TCR events during microneurosurgery involving the second and third divisions of the trigeminal nerve. MATERIALS AND METHODS: This was a retrospective cohort study of 94 patients who underwent nerve repair of the second and third divisions of the trigeminal nerve, between July 2014 and February 2021 by a single surgeon (J. Z.). The independent variables were the trigeminal nerve branch injured, the laterality of the trigeminal nerve injury, the Sunderland classification, the ASA classification, the intraoperative narcotic(s) used, and the depth of anesthesia. The dependent variables included the occurrence of intraoperative hypercapnia, hypoxia, and TCR event. Since the data was retrospective and categorical in nature, χ2 analysis was performed initially. RESULTS: None of the patients in this retrospective cohort demonstrated intraoperative hypercapnia, hypoxia or TCR events. Initial χ2 calculation was performed for the dependent variables with the trigeminal nerve groups (IAN, LN, and ION). The χ2 calculation [χ2 (1, n = 101)] was 0.2235. The P-value was .6364. Since there was no statistical significance found, there was no further analysis of surgical and anesthesia independent variables in the data collection. CONCLUSIONS: The zero incidence of TCR in a large number of patients provides strong evidence supporting the rejection of the hypothesis that TCR can occur during the surgical repair of peripheral trigeminal nerves.

Save 100 Babies©: engaging communities for just and equitable birth outcomes through Photovoice and Appreciative Inquiry.

This paper presents a community engagement model designed to advance social justice and equity for African American birth outcomes through the combined techniques of Photovoice and Appreciative Inquiry. In response to the persistent racial disparities in birth outcomes, Save 100 Babies© was constructed as a 2-day summit where the emphasis was placed on individual and community assets rather than deficits. The engagement was designed to create a level of readiness among individuals working within and outside the field of Maternal and Child Health to envision strategies to attain equitable birth outcomes. The goal of the conference was to facilitate higher level consciousness by guiding the participants though a process aimed at articulating assets, possibilities and the potential for co-creating the desired futures where racial disparities in birth outcome are eliminated [corrected]. As the result of the guided discourse that began with photographs of the lives of African American women, participants articulated the strengths they detected from the pictures, their recommendations for multifaceted changes in policies and practices, and their individual and organizational commitments for a changed future. Since the summit, participants have indicated ways they have fulfilled their vows that include informing families and communities about pregnancy risks, working with youth programs, supporting fatherhood involvement in pregnancy and birth, and advancing case management that is more attuned to women's strengths. Save 100 Babies© is evolving into a network and clearinghouse for sharing and disseminating information and resources for collaboration.

Synthetic polypeptides using a biologic as a reference medicinal product - the European landscape of regulatory approvals.

Recent advances in synthetic drug manufacturing have introduced a new dynamic to the European regulatory system, with chemically synthesized polypeptide products using biological originator products as their reference medicine. Whereas biosimilars are subject to a dedicated regulatory framework in the EU, synthetically produced follow-on products are not eligible for assessment through this pathway, requiring approval via the traditional generic pathway under Article 10 (1), or via the hybrid pathway under Article 10 (3). This review presents an overview of recent developments in the field of synthetic peptides referencing biological originators in the EU. The use of different regulatory procedures can have potential implications for regulatory assessments, clinical practice and pharmacovigilance. As more complex synthetic products referencing recombinant originator products are expected in the coming years, this study promotes more transparency as well as global alignment about regulatory procedures for chemically synthesised products referencing biological originator products to ensure approval of safe and high-quality generics.

In Operando Imaging Electrostatic-Driven Disassembly and Reassembly of Collagen Nanostructures.

Collagen is the most abundant protein in tissue scaffolds in live organisms. Collagen can self-assemble in vitro, which has led to a number of biotechnological and biomedical applications. To understand the dominant factors that participate in the formation of collagen nanostructures, here we study in real time and with nanoscale resolution the disassembly and reassembly of collagens. We implement a high-speed force microscope, which provides in situ high spatiotemporal resolution images of collagen nanostructures under changing pH conditions. The disassembly and reassembly are dominated by the electrostatic interactions among amino-acid residues of different molecules. Acidic conditions favor disassembly by neutralizing negatively charged residues. The process sets a net repulsive force between collagen molecules. A neutral pH favors the presence of negative and positively charged residues along the collagen molecules, which promotes their electrostatic attraction. Molecular dynamics simulations reproduce the experimental behavior and validate the electrostatic-based model of the disassembly and reassembly processes.

The Global Landscape of Manufacturers of Follow-on Biologics: An Overview of Five Major Biosimilar Markets and 15 Countries.

BACKGROUND: Current knowledge is limited about which manufacturers are active in the global field of biopharmaceutical product development and how many unique follow-on biologics are approved in global markets. OBJECTIVE: This study aimed to provide a cross-sectional overview of manufacturers of follow-on biologics approved in 15 large countries from different regions of the world, as well as in five major biosimilar markets with long established biosimilar frameworks. METHODS: We screened national drug databases to identify follow-on biologics and their manufacturers approved in 15 countries in Asia, Africa, Latin America and the rest of the world, as well as five major biosimilar markets: the European Union (including the UK), USA, Canada, Australia and Japan. RESULTS: This study identified a total of 304 follow-on biologics from different manufacturers for 18 active substance classes included in the analysis. Of these, 67 products are approved as biosimilars in at least one of the five major biosimilar markets. A total of 140 (46%) follow-on biologics are manufactured in India or China, of which only eight (seven from India and one from China) are approved as biosimilars in any of the five major biosimilar markets. This study found that the majority of follow-on biologics are only approved in the respective country of manufacturing. A small number of manufacturers, primarily from India and Argentina, supply their products to other regions in the world. As some countries have less stringent regulatory approaches for biosimilars, or have only recently implemented biosimilar guidance in line with World Health Organization standards, follow-on biologics could have been approved that would not be considered biosimilars according to the World Health Organization standards. CONCLUSIONS: With this study, we try to contribute to discussions on creating more transparency about global approvals of follow-on biologics and promoting access to high-quality biosimilars in countries around the world.

Biological and substitute parents in Beaker period adult-child graves.

Joint inhumations of adults and children are an intriguing aspect of the shift from collective to single burial rites in third millennium BC Western Eurasia. Here, we revisit two exceptional Beaker period adult-child graves using ancient DNA: Altwies in Luxembourg and Dunstable Downs in Britain. Ancestry modelling and patterns of shared IBD segments between the individuals examined, and contemporary genomes from Central and Northwest Europe, highlight the continental connections of British Beakers. Although simultaneous burials may involve individuals with no social or biological ties, we present evidence that close blood relations played a role in shaping third millennium BC social systems and burial practices, for example a biological mother and her son buried together at Altwies. Extended family, such as a paternal aunt at Dunstable Downs, could also act as 'substitute parents' in the grave. Hypotheses are explored to explain such simultaneous inhumations. Whilst intercommunity violence, infectious disease and epidemics may be considered as explanations, they fail to account for both the specific, codified nature of this particular form of inhumation, and its pervasiveness, as evidenced by a representative sample of 131 adult-child graves from 88 sites across Eurasia, all dating to the third and second millennia BC.

HIV Gag-leucine zipper chimeras form ABCE1-containing intermediates and RNase-resistant immature capsids similar to those formed by wild-type HIV-1 Gag.

During HIV-1 assembly, Gag polypeptides multimerize to form an immature capsid and also package HIV-1 genomic RNA. Assembling Gag forms immature capsids by progressing through a stepwise pathway of assembly intermediates containing the cellular ATPase ABCE1, which facilitates capsid formation. The NC domain of Gag is required for ABCE1 binding, acting either directly or indirectly. NC is also critical for Gag multimerization and RNA binding. Previous studies of GagZip chimeric proteins in which NC was replaced with a heterologous leucine zipper that promotes protein dimerization but not RNA binding established that the RNA binding properties of NC are dispensable for capsid formation per se. Here we utilized GagZip proteins to address the question of whether the RNA binding properties of NC are required for ABCE1 binding and for the formation of ABCE1-containing capsid assembly intermediates. We found that assembly-competent HIV-1 GagZip proteins formed ABCE1-containing intermediates, while assembly-incompetent HIV-1 GagZip proteins harboring mutations in residues critical for leucine zipper dimerization did not. Thus, these data suggest that ABCE1 does not bind to NC directly or through an RNA bridge, and they support a model in which dimerization of Gag, mediated by NC or a zipper, results in exposure of an ABCE1-binding domain located elsewhere in Gag, outside NC. Additionally, we demonstrated that immature capsids formed by GagZip proteins are insensitive to RNase A, as expected. However, unexpectedly, immature HIV-1 capsids were almost as insensitive to RNase A as GagZip capsids, suggesting that RNA is not a structural element holding together immature wild-type HIV-1 capsids.

Regulatory Flexibilities and Guidances for Addressing the Challenges of COVID-19 in the EU: What Can We Learn from Company Experiences?

The COVID-19 pandemic required urgency in the development and delivery of effective vaccines and therapeutics; meanwhile, ongoing clinical research, regulation and supply for other much-needed therapeutics and vaccines needed to be sustained. In Europe, the European Commission, the European Medicines Agency (EMA) and the national regulatory agencies (NRAs) responded by issuing guidance outlining regulatory flexibilities mainly directed at COVID-19 vaccines and, belatedly, therapeutics. Using a survey methodology, this study gathered the views of the R&D based pharmaceutical industry in May-June 2021 on the value of these flexibilities for continued use in the post-pandemic era as well as for future use in health emergency situations. Findings indicate that many flexibilities were foreseen to have value beyond the pandemic, particularly where EU and Member States aligned closely to provide a singular, streamlined regulatory environment. Digitalization was a notable driver of these flexibilities, but innovations in regulatory process (e.g. rolling reviews, flexible Scientific Advice) improved the process and outcomes measurably. Finally, the rapid reaction of the EU regulatory system and extensive efforts by all involved in providing innovative therapeutics and vaccines to patients in need provides learnings for the upcoming overhaul of the pharmaceutical acquis.

Four scenarios for the future of medicines and social policy in 2030.

The future of medicines is likely determined by an array of scientific, socioeconomic, policy, medical need, and geopolitical factors, with many uncertainties ahead. Here, we report from a scenario project, analyzing various trends, crucial and complex developments in the medicines' space. From a range of 'critical uncertainties' we derived two scenario drivers: global convergence, ranging from very high (trust and solidarity), to very low (fragmented ecosystems); and disease orientation, ranging from public health first to interceptive medicine. This resulted in four contrasting portraits of the future of medicines and social policy: deprioritizing the high-end; sustainable flow; transformative healing; and global divide. All those involved in drug discovery and development can use these for strengthening preparedness for the crucial challenges ahead.

Innate immune signaling induces high levels of TC-specific deaminase activity in primary monocyte-derived cells through expression of APOBEC3A isoforms.

In HIV-1-infected individuals, G-to-A hypermutation is found in HIV-1 DNA isolated from peripheral blood mononuclear cells (PBMCs). These mutations are thought to result from editing by one or more host enzymes in the APOBEC3 (A3) family of cytidine deaminases, which act on CC (APOBEC3G) and TC (other A3 proteins) dinucleotide motifs in DNA (edited cytidine underlined). Although many A3 proteins display high levels of deaminase activity in model systems, only low levels of A3 deaminase activity have been found in primary cells examined to date. In contrast, here we report high levels of deaminase activity at TC motifs when whole PBMCs or isolated primary monocyte-derived cells were treated with interferon-alpha (IFNalpha) or IFNalpha-inducing toll-like receptor ligands. Induction of TC-specific deaminase activity required new transcription and translation and correlated with the appearance of two APOBEC3A (A3A) isoforms. Knockdown of A3A in monocytes with siRNA abolished TC-specific deaminase activity, confirming that A3A isoforms are responsible for all TC-specific deaminase activity observed. Both A3A isoforms appear to be enzymatically active; moreover, our mutational studies raise the possibility that the smaller isoform results from internal translational initiation. In contrast to the high levels of TC-specific activity observed in IFNalpha-treated monocytes, CC-specific activity remained low in PBMCs, suggesting that A3G deaminase activity is relatively inhibited, unlike that of A3A. Together, these findings suggest that deaminase activity of A3A isoforms in monocytes and macrophages may play an important role in host defense against viruses.

Regulatory density as a means to refine current regulatory approaches for increasingly complex medicines.

The continuous scientific, societal, and technological advancements have shifted drug development toward increasingly complex and ever more targeted treatments. This creates new and unprecedented challenges for global regulatory systems. To address the increased risks and uncertainties of increasingly complex medicine, we advocate for a more tailored and flexible regulatory approach, which is explained here with the concept of 'regulatory density'. In the context of this paper, 'regulatory density' describes the relative amount of obligatory standards, measures and procedures applied to certain medicinal products or product classes and the resources required to meet these requirements. Given that risk and uncertainty are dynamic variables that can change over time, with this paper, we want to stimulate (re)thinking of regulatory approaches for managing the challenges of future complex medicines.

Sensitivity of Laségue Sign and Slump Test in Hernia and Disc Bulging Diagnoses Compared with Magnetic Resonance Imaging.

Objective To show the accuracy of the most used maneuvers in the clinical diagnosis of lumbosciatalgia, the slump test and the Laségue sign. Methods In order to perform the present study, 101 patients with magnetic resonance imaging (MRI) discopathy (gold standard) were selected and had their medical records reviewed to identify which had the positive maneuvers on the initial physical examination. Results The sensitivity found for the slump test and the Laségue sign in the diagnosis of disc herniation was 55.3% and 18.1%, respectively. Nonetheless, when they were compared with each other for the diagnosis of disc bulging, the sensitivity obtained was of 85.7% for the slump test and of 28.6% for the Laségue sign. Conclusion Comparing both clinical exams with MRI, it was found that the slump test presents superior sensitivity compared with the Laségue sign for both the diagnosis of hernia and disc bulging, and should be more present in clinical practice.

A pragmatic regulatory approach for complex generics through the U.S. FDA 505(j) or 505(b)(2) approval pathways.

The diverse nature of complex drug products poses challenges for the development of regulatory guidelines for generic versions. While complexity is not new in medicines, the technical capacity to measure and analyze data has increased. This requires a determination of which measurements and studies are relevant to demonstrate therapeutic equivalence. This paper describes the views of the NBCD Working Group and provides pragmatic solutions for approving complex generics by making best use of existing U.S. Food and Drug Administration's abbreviated approval pathways 505(j) and 505(b)(2). We argue that decisions on the appropriateness of submitting a 505(j) or 505(b)(2) application can build on the FDA's complex drug product classification as well as the FDA's much applauded guidance document for determining whether to submit an ANDA or a 505(b)(2) application. We hope that this paper contributes to the discussions to increase the clarity of regulatory approaches for complex generics, as well as the predictability for complex generic drug developers, to facilitate access to much-needed complex generics and to promote the sustainability of the healthcare system.

The UK BIO-TRAC Study: A Cross-Sectional Study of Product and Batch Traceability for Biologics in Clinical Practice and Electronic Adverse Drug Reaction Reporting in the UK.

INTRODUCTION: Due to the complexity of biologics and the inherent challenges for manufacturing, it is important to know the specific brand name and batch number of suspected biologics in adverse drug reaction (ADR) reports. OBJECTIVE: The aim of this study was to assess the extent to which biologics are traceable by brand name and batch number in UK hospital practice and in ADRs reported by patients and healthcare professionals. METHODS: We performed an online hospital pharmacist survey to capture information on how specific product details are recorded during the processes of prescribing, dispensing and administration of biologics in routine UK hospital practice. We also assessed the proportion of ADR reports specifying brand name and batch number from electronic ADR reports submitted to the UK national spontaneous reporting database, the Yellow Card Scheme, between 1 January 2009 and 30 September 2017. RESULTS: Brand name recording in routine hospital processes ranged from 79 to 91%, whereas batch numbers were less routinely recorded, ranging from 38 to 58%. Paper-based recording of product details was more commonly used for recording information. A total of 6108 electronic ADR reports were submitted to the Yellow Card Scheme for recombinant biologics, of which 38% and 15%, respectively, had an identifiable brand name and batch numbers. Whereas batch number traceability in electronic ADR reports improved slightly after the implementation of the European Union pharmacovigilance legislation in 2012, no improvement of brand name traceability was observed. CONCLUSION: Brand name and batch number traceability for biologics in UK ADR reports are generally low. Shortcomings in the systematic recording of product details in UK clinical practice may contribute to the limited traceability.

Trigeminocardiac Reflex Induced by Maxillary Nerve Stimulation during Sphenopalatine Ganglion Implantation: A Case Series.

BACKGROUND: The trigeminocardiac reflex (TCR) is a brainstem reflex following stimulation of the trigeminal nerve, resulting in bradycardia, asystole and hypotension. It has been described in maxillofacial and craniofacial surgeries. This case series highlights TCR events occurring during sphenopalatine ganglion (SPJ) neurostimulator implantation as part of the Pathway CH-2 clinical trial "Sphenopalatine ganglion Stimulation for Treatment of Chronic Cluster Headache". METHODS: This is a case series discussing sphenopalatine ganglion neurostimulator implantation in the pterygopalatine fossa as treatment for intractable cluster headaches. Eight cases are discussed with three demonstrating TCR events. All cases received remifentanil and desflurane for anesthetic maintenance. RESULTS: Each patient with a TCR event experienced severe bradycardia. In two cases, TCR resolved with removal of the introducer, while the third case's TCR event resolved with both anticholinergic treatment and surgical stimulation cessation. CONCLUSION: Each TCR event occurred before stimulation of the fixed introducer device, suggesting the cause for the TCR events was mechanical in origin. Due to heightened concern for further TCR events, all subsequent cases had pre-anesthesia external pacing pads placed. Resolution can occur with cessation of surgical manipulation and/or anticholinergic treatment. Management of TCR events requires communication between surgical teams and anesthesia providers, especially during sphenopalatine ganglion implantation when maxillary nerve stimulation is possible.

Intravenous vs oral acetaminophen in sinus surgery: A randomized clinical trial.

BACKGROUND: Multimodal perioperative analgesia including acetaminophen is recommended by current guidelines. The comparative efficacy of intravenous vs oral acetaminophen in sinus surgery is unknown. We aimed to determine whether intravenous or oral acetaminophen results in superior postoperative analgesia following sinus surgery. METHODS: This was a prospective randomized trial with blinded endpoint assessments conducted at a single large academic medical center. Subjects undergoing functional endoscopic sinus surgery were randomized to intravenous vs oral acetaminophen in addition to standard anesthetic and surgical care. The primary outcome was visual analogue scale pain score at 1 hour postoperatively. RESULTS: One hundred and ten adult patients were randomized; 9 were excluded from the data analysis. Fifty patients were assigned to intravenous acetaminophen and 51 to oral acetaminophen. Postoperative pain scores at 1 hour (primary endpoint) were not significantly different between the intravenous and oral acetaminophen groups. Similarly, there was no significant difference in pain scores at 24 hours postoperatively. Finally, there was no significant difference in postoperative opioid usage in the postanesthesia care unit or over the first 24 hours postoperatively. CONCLUSIONS: This is the first comparative efficacy trial of oral vs intravenous acetaminophen in sinus surgery. There was no significant difference in pain scores at 1 or 24 hours postoperatively, and no difference in postoperative opioid use. Intravenous acetaminophen offers no apparent advantage over oral acetaminophen in patients undergoing sinus surgery. LEVEL OF EVIDENCE: 1b.

Cervical Spine Movement in a Cadaveric Model of Severe Spinal Instability: A Study Comparing Tracheal Intubation with 4 Different Laryngoscopes.

BACKGROUND: This study compared the Macintosh blade direct laryngoscope, Glidescope, C-Mac d-Blade, and McGrath MAC X-blade video laryngoscopes in 2 cadaveric models with severe cervical spinal instability. We hypothesized that the Glidescope video laryngoscope would allow for intubation with the least amount of cervical spine movement. Our secondary endpoints were glottic visualization and intubation success. METHODS: In total, 2 fresh cadavers underwent maximal surgical destabilization from the craniocervical junction to the cervicothoracic junction by a neurosurgical spine specialist, with subsequent neutral positioning of the heads with surgical head fixation devices. On each cadaver, 8 experienced anesthesiologists performed four intubations with the 4 laryngoscopes in random order. Lateral radiographic measurements determined vertebral displacement during intubation. RESULTS: Cervical spine displacements were not significantly different amongst video laryngoscopes. Cormack-Lehane Grade 1 views were achieved with all attempts with each of the 3 video laryngoscopes; intubation attempts with the Macintosh blade achieved only grade 3 or grade 4 views. Intubation was successful every time with a video laryngoscope but only during 1 of 16 intubation attempts with the Macintosh blade. CONCLUSIONS: In a cadaveric model with maximally destabilized cervical spines, cervical spine movement was observed during attempted laryngoscopy using each of 3 video laryngoscopes, although there was no significant difference between the laryngoscopes. Given cervical spine displacement occurred, these video laryngoscopes do not prevent cervical spine motion during laryngoscopy. However, with improved glottic visualization and intubation success, video laryngoscopes are superior to the Macintosh blade in both cervical spine safety and intubation efficacy in the model studied.

T cells contain an RNase-insensitive inhibitor of APOBEC3G deaminase activity.

The deoxycytidine deaminase APOBEC3G (A3G) is expressed in human T cells and inhibits HIV-1 replication. When transfected into A3G-deficient epithelial cell lines, A3G induces catastrophic hypermutation by deaminating the HIV-1 genome. Interestingly, studies suggest that endogenous A3G in T cells induces less hypermutation than would be expected. However, to date, the specific deaminase activity of endogenous A3G in human CD4+ T cells has not been examined directly. Here, we compared deaminase activity of endogenous and exogenous A3G in various human cell lines using a standard assay and a novel, quantitative, high-throughput assay. Exogenous A3G in epithelial cell lysates displayed deaminase activity only following RNase treatment, as expected given that A3G is known to form an enzymatically inactive RNA-containing complex. Surprisingly, comparable amounts of endogenous A3G from T cell lines or from resting or activated primary CD4+ T cells exhibited minimal deaminase activity, despite RNase treatment. Specific deaminase activity of endogenous A3G in H9, CEM, and other T cell lines was up to 36-fold lower than specific activity of exogenous A3G in epithelial-derived cell lines. Furthermore, RNase-treated T cell lysates conferred a dose-dependent inhibition to epithelial cell lysates expressing enzymatically active A3G. These studies suggest that T cells, unlike epithelial-derived cell lines, express an unidentified RNase-resistant factor that inhibits A3G deaminase activity. This factor could be responsible for reduced levels of hypermutation in T cells, and its identification and blockade could offer a means for increasing antiretroviral intrinsic immunity of T cells.

The effect of pregabalin on preoperative anxiety and sedation levels: a dose-ranging study.

BACKGROUND: Pregabalin is a gabapentinoid compound, which has been alleged to possess anxiolytic, analgesic, and anticonvulsant properties. We hypothesized that premedication with oral pregabalin would produce dose-related reductions in acute (state) anxiety and increases in sedation (sleepiness) before induction of general anesthesia. A secondary objective was to determine if premedication with pregabalin would reduce postoperative pain. METHODS: One hundred eight ASA I-III outpatients undergoing elective surgery were randomly assigned to one of the four premedication treatment groups: 1) control group received placebo capsules, 2) pregabalin 75 group received pregabalin 75 mg, po, 3) pregabalin 150 group received pregabalin 150 mg, po, and 4) pregabalin 300 group received pregabalin 300 mg, po. The effects of the study drug on the patients' level of anxiety, sedation, and pain were assessed at baseline (immediately before study drug administration), at 30 and 60 min after drug administration, and immediately before induction of anesthesia, as well as at 30-min intervals in the postanesthesia care unit (PACU) using standardized 11-point verbal rating scales, with 0 = none to 10 = maximal effect. The need for postoperative opioid analgesic medication, incidence of nausea and vomiting, requirement for rescue antiemetics, and times to discharge from the PACU and hospital, as well as the patients' quality of recovery scores, and late recovery outcomes (e.g., resumption of dietary intake and recovery of bowel function) were assessed at a 7-day follow-up interview. RESULTS: Demographic characteristics, times between study drug administration to anesthetic induction, type of surgical procedures, duration of anesthesia, PACU and hospital discharge time, as well as the requirement for fentanyl in the PACU, did not differ among the four study groups. Anxiety levels remained unchanged during the preoperative evaluation period, and did not differ among the four study groups. Sedation scores were significantly higher in the pregabalin 300 group at the preinduction assessment interval and at 90 and 120 min after surgery compared with the control group (5 +/- 3 vs 3 +/- 2, 7 +/- 4 vs 5 +/- 3, 8 +/- 4 vs 4 +/- 4, respectively, P < 0.05). CONCLUSION: Preoperative pregabalin administration (75-300 mg po) increased perioperative sedation in a dose-related fashion, but failed to reduce preoperative state anxiety, postoperative pain, or to improve the recovery process after minor elective surgery procedures.