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Oxytocin is an endogenous neuropeptide hormone that influences social behaviour and bonding in mammals. Variations in oxytocin receptor (OXTR) expression may play a role in the social deficits seen in autism spectrum disorder. Previous studies from our laboratory found a dense population of OXTR in the human substantia nigra (SN), a basal ganglia structure in the midbrain that is important in both movement and reward pathways. Here, we explore whether differences in OXTR can be identified in the dopaminergic SN pars compacta of individuals with autism. Postmortem human brain tissue specimens were processed for OXTR autoradiography from four groups: males with autism, females with autism, typically developing (TD) males and TD females. We found that females with autism had significantly lower levels of OXTR than the other groups. To examine potential gene expression differences, we performed in situ hybridization in adjacent slides to visualize and quantify OXTR mRNA as well as mRNA for tyrosine hydroxylase. We found no differences in mRNA levels for either gene across the four groups. These results suggest that a dysregulation in local OXTR protein translation or increased OXTR internalization/recycling may contribute to the differences in social symptoms seen in females with autism. This article is part of the theme issue ‘Interplays between oxytocin and other neuromodulators in shaping complex social behaviours’.

The design and development of analgesics with mixed-opioid receptor interactions has been reported to decrease side effects, minimizing respiratory depression and reinforcing properties to generate safer analgesic therapeutics. We synthesized bis-cyclic guanidine heterocyclic peptidomimetics from reduced tripeptides. In vitro screening with radioligand competition binding assays demonstrated variable affinity for the mu-opioid receptor (MOR), delta-opioid receptor (DOR), and kappa-opioid receptor (KOR) across the series, with compound 1968-22 displaying good affinity for all three receptors. Central intracerebroventricular (i.c.v.) administration of 1968-22 produced dose-dependent, opioid receptor-mediated antinociception in the mouse 55 °C warm-water tail-withdrawal assay, and 1968-22 also produced significant antinociception up to 80 min after oral administration (10 mg/kg, p.o.). Compound 1968-22 was detected in the brain 5 min after intravenous administration and was shown to be stable in the blood for at least 30 min. Central administration of 1968-22 did not produce significant respiratory depression, locomotor effects or conditioned place preference or aversion. The data suggest these bis-cyclic guanidine heterocyclic peptidomimetics with multifunctional opioid receptor activity may hold potential as new analgesics with fewer liabilities of use.

Chapter 3 introduces the reader to various aspects of sign languages, including their historical development and use within educational contexts by Deaf communities in Europe and the United States. Also covered is the initiation of the field of sign language linguistics by William C. Stokoe, a linguist who systematically proved that American Sign Language (ASL) was indeed a language with its own distinct structure and properties that differed from any spoken language. The phonological parameters of signs receive considerable attention, highlighting ways in which the unique properties of sign languages allow them to represent meaning in ways that are more consistently transparent and iconic than similar phenomena in the speech modality. Despite these similarities across sign languages, the differences among the sign languages of the world led Deaf persons to create and develop the lingua franca of International Sign (previously Gestuno) for use at international conventions. Finally, the similarities and distinctions between the processes of language development and acquisition across the modalities of speech and sign are discussed, as well as how signing benefits the learning of spoken language vocabulary by hearing children.

Chapter 5 provides a comprehensive, historical overview of the defining characteristics of autism spectrum disorder (ASD) along with the various language therapies employed to improve the communicative success of minimally verbal individuals. The various strengths and weaknesses of such approaches are analyzed as a basis for helping to determine which methods are likely to be the most successful. The history of signing in persons with ASD is examined, with a special focus on the relatively recent realization that motor skills (both gross and fine) and imitation abilities in such individuals may be severely impaired, thus limiting the effectiveness of sign interventions that do not take into consideration the motor complexity of the signs used. Since many parents and caregivers may also express reluctance to adopt a strategy that uses signs out of fear that this will prevent their child’s acquisition of speech, research dispelling this myth is provided. In addition to coverage of sign-communication interventions and strategies for promoting spontaneous communication and generalization of sign use to multiple settings, other non-oral approaches employed with persons with disabilities are presented as options, including the use of real objects, the Picture Exchange Communication System (PECS), Blissymbols, speech-generating devices, and software applications.

Chapter 10 provides an introduction to the organization of the Simplified Sign System lexicon and its supporting materials. This chapter explains the various conventions used in the sign illustrations so that learners can accurately interpret the drawings, including the numbering of initial, intermediate, and final positions; the size, shape, and repetition of arrows, quotes, and other marks that depict the sign’s movement; and the provision of facial expressions on signs that convey emotional information. Drawings and expanded written descriptions of the handshapes used in the Simplified Sign System are provided, along with information on how prevalent each handshape is in the system and a sampling of the particular meanings that a handshape can convey within the system. Drawings and written descriptions of the various palm orientations and finger/knuckle orientations used in the system are provided as well so that family members, educators, and other professionals will be able to accurately interpret each sign’s written description. Also discussed in this chapter are the memory aids provided with each sign, natural variations in sign formation and production that are to be expected, as well as what to do if a sign learner has functional use of only one hand and arm.

Chapter 11 contains the first one thousand signs of the Simplified Sign System lexicon, alphabetized by each sign’s main gloss. Each entry in the lexicon includes a hand-drawn illustration of how that sign is formed, a listing of any synonyms or antonyms related to that sign, and a written description of how the sign is formed (i.e., the handshape(s), palm orientation(s), finger/knuckle orientation(s), location, and movement parameters of the sign). Also provided are a short memory aid to help learners remember the sign’s formation and a longer memory aid that describes the visual and iconic link between how the sign is physically formed and the meaning it conveys. Many of the longer memory aids also include a definition of the main gloss and some of that sign’s synonyms. If users of the system wish to look up a particular vocabulary item, term, or idiomatic phrase, an alphabetized Sign Index that integrates all of the main sign glosses with all of their listed synonyms and antonyms is provided at the end of the volume. This Sign Index directs readers to the page that contains the main sign entry, its written description, and its memory aids.

Chapter 1 provides an introduction to the language and communication needs of various individuals who have difficulty expressing themselves either through speech and/or by using one of the full and genuine sign languages of Deaf people. The authors propose the integration of the Simplified Sign System, a manual sign-communication system that is comprised of iconic and easily formed signs, into the environments of persons with various communication difficulties, including individuals with autism, aphasia, intellectual disability, or cerebral palsy. Various misconceptions about sign training are tackled and countered by information highlighting the benefits of sign usage for many different people. The authors then present the principles on which their sign system is based, including iconicity, ease of production, the relatively broad conceptual base of many signs, the standardization of the signs, and the provision of a core vocabulary. These principles also make them easier to learn and remember by other potential users of the system, including international travellers, parents adopting children from other countries, elderly persons who have developed hearing impairments, foreign language instructors, and students learning an additional spoken language.

Chapter 2 presents multiple accounts of the widespread use of manual signs by hearing persons in diverse settings throughout history. From an initial theoretical focus on the origins of language in humans, and the potential that language first emerged from gestural or manual communication, the reader is introduced to the views of various historical scholars who believed that signs and gestures are a natural means of communication and could potentially even be a universal form of communication. Such a universal form of communication, however, meets with a substantial obstacle in that gestures may vary widely in meaning and usage cross-culturally. Nevertheless, such a system was developed once before by the Indigenous peoples of North America, who spoke hundreds of different languages. Native Americans used signs as a lingua franca across a wide geographical area to overcome the numerous spoken language barriers they encountered. Also covered in this chapter are the use of signs in early contact situations and interactions between Native Americans and Europeans, and the development of signs by various monastic orders in Europe.

In Chapter 7, the authors change focus from the use of signs by deaf persons and with individuals with disabilities to how signing may enhance the learning and processing of spoken language by typically developing hearing children and adults. The first topic examined is the use of signs to foster infants’ and young children’s acquisition of their principal spoken language. Signs may further serve as an effective intervention strategy in academic settings for children with ADHD or as a means to improving vocabulary acquisition and reading comprehension for children who lag behind their age group on various language performance measures. Iconic signs and representative gestures may also be used to facilitate the acquisition of foreign language vocabulary when the signs are paired with the to-be-learned words. Finally, various studies concerning the positive benefits of learning to sign promote the possibility that using the visual-gestural modality may confer increased skills in various cognitive domains such as spatial memory, mental rotation, and facial discrimination.

Chapter 8 provides background information on the development of the Simplified Sign System. These steps are included so that investigators may replicate research findings and/or develop additional signs for their own sign-intervention programs. The authors first discuss efforts to find highly iconic or representative gestures in the dictionaries of various sign languages and sign systems from around the world. If necessary, signs were then modified to make them easier to produce based on the results of prior studies of signing errors made by students with autism, the sign-learning children of Deaf parents, and undergraduate students unfamiliar with any sign language. These potential signs were then tested with different undergraduate students to determine whether the signs were sufficiently memorable and accurately formed. Signs that did not meet criterion were either dropped from the system or subsequently modified and re-tested. Initial results from comparison studies between Simplified Signs and ASL signs and between Simplified Signs and Amer-Ind signs are presented as well. Finally, feedback from users influenced the course of the project. Memory aids were developed, especially for those persons who have less familiarity with sign languages, to help explain the ties between each sign and its referent in case that relationship is not readily or immediately apparent to a potential learner.

Simplified Signspresents a system of manual sign communication intended for special populations who have had limited success mastering spoken or full sign languages. It is the culmination of over twenty years of research and development by the authors. The Simplified Sign System has been developed and tested for ease of sign comprehension, memorization, and formation by limiting the complexity of the motor skills required to form each sign, and by ensuring that each sign visually resembles the meaning it conveys.Volume 1 outlines the research underpinning and informing the project, and places the Simplified Sign System in a wider context of sign usage, historically and by different populations.

Chapter 6 focuses on the language and communication impairments of adults and children that may be acquired after suffering a head injury, stroke, brain infection, tumor, or other similar trauma. Such persons may have had intact language abilities before the trauma, but often present with varying degrees of severity of aphasia that may temporarily or permanently affect their receptive understanding of language and/or their production of language. Although most of the literature examines such deficits in hearing persons and the resulting impact on spoken language, deaf persons may also experience aphasic impairments to their production and understanding of sign language. An examination of apraxia, which often co-occurs with aphasia, provides another dimension that needs to be analyzed when addressing strategies for language rehabilitation. The outcomes of sign-communication interventions in persons with aphasia are presented, along with a focus on Amer-Ind, pantomime skills, and the use of signing to facilitate speech. Finally, the authors address speech and language disorders such as acquired childhood aphasia (Landau-Kleffner syndrome), developmental language disorder (formerly known as specific language impairment) in both hearing and deaf children, and childhood apraxia of speech.

In Chapter 9, various approaches to teaching signs to non-speaking or minimally verbal persons are examined, including general exposure, an incidental or milieu approach, games and group activities, and specific training sessions. Learning goals are identified not only for the main or primary user of the system, but also for that person’s communication partners (family members, caregivers, friends) and persons in the wider environment. Guidelines for using the Simplified Sign System with the target populations are provided in order to establish good and consistent communication practices that will help to maximize users’ success with the system. Such guidelines or strategies include ensuring a positive signing environment, establishing visual contact, using key word signing, accepting errors in sign formation from the main user, rewarding progress, using facial expressions and environmental cues or contextual information to enhance vocabulary acquisition, and adapting the rate and frequency of signing. Finally, the authors anticipate and address many of the questions or concerns that teachers or caregivers may have as they embark on a program of using Simplified Signs.

In Chapter 4, the authors begin an in-depth discussion of the use of signs with special populations, including an early study that occurred in the West of England in the 1840s with deaf students with intellectual disabilities. Various types of intellectual disability are identified, including fragile X syndrome, Williams syndrome, Down syndrome, and Angelman syndrome. The successes and failures of speech-based and sign-based interventions are covered for individuals with these syndromes (particularly the latter two) as well as in persons with multiple disabilities. The authors next move on to a discussion of the relatively sparse research related to teaching signs to children who have cerebral palsy. Recommendations for enhancing the sign-learning environment are provided so that all persons who use signs as an augmentative or alternative means of communication may derive the greatest benefit from their communicative interactions. In addition to maximizing the positive atmosphere in which signing individuals interact with others at school, at home, and in public, the authors suggest that the types of signs employed may also have an impact on whether or not signing is successful.

Ocean pH has been declining since the start of the Industrial Revolution, and is predicted to continue declining for at least another 200 years. Although the chemical cues that induce larval metamorphosis in marine invertebrates in part determine the distribution and persistence of many coastal marine communities, few studies have examined the effects of ocean acidification on the timing of metamorphic competence or the ability of larval invertebrates to metamorphose in response to environmental cues. Working with larvae of the marine gastropod Crepidula fornicata, we examined the impacts of sudden, short-term (2 h), and prolonged (several weeks) exposure to reduced pH as low as 7.5 on larval survival and growth, the onset of metamorphic competence, and the ability of larvae to perceive inductive cues and metamorphose in their presence. Unexpectedly, although larvae reared at pH 7.5 grew more slowly and took longer to become competent to metamorphose, exposure to acidified conditions did not appreciably impair larval cue perception for metamorphosis.

Numerous studies demonstrate the promise of opioid peptides as analgesics, but poor oral bioavailability has limited their therapeutic development. This study sought to increase the oral bioavailability of opioid peptides by cyclization, using Hantzsch-based macrocyclization strategies to produce two new series of cyclized DAMGO and Leu/Met-enkephalin analogs. Opioid receptor affinity and selectivity for compounds in each series were assessed in vitro with radioligand competition binding assays. Compounds demonstrated modest affinity but high selectivity for the mu, delta, and kappa opioid receptors (MOR, DOR and KOR), while selectivity for mu opioid receptors varied by structure. Antinociceptive activity of each compound was initially screened in vivo following intracerebroventricular (i.c.v.) administration and testing in the mouse 55 °C warm-water tail-withdrawal test. The four most active compounds were then evaluated for dose- and time-dependent antinociception, and opioid receptor selectivity in vivo. Cyclic compounds 1924-10, 1936-1, 1936-7, and 1936-9 produced robust and long- lasting antinociception with ED50 values ranging from 0.32–0.75 nmol following i.c.v. administration mediated primarily by mu- and delta-opioid receptor agonism. Compounds 1924-10, 1936-1 and 1936-9 further displayed significant time-dependent antinociception after oral (10 mg kg−1, p.o.) administration. A higher oral dose (30 mg kg−1. p.o.) of all four cyclic peptides also reduced centrally-mediated respiration, suggesting successful penitration into the CNS. Overall, these data suggest cyclized opioid peptides synthesized by a Hantzsch-based macrocyclization strategy can retain opioid agonist activity to produce potent antinociception in vivo while conveying improved bioavailability following oral administration.

A novel and facile domino reaction has been developed to synthesize a variety of new derivatives from hydromorphone, amines and paraformaldehyde in good yields in a catalyst-free fashion with high atom efficiency. The products show a mixed MOR/DOR biological characteristic which makes them valuable for further study as opioid analgesics.

To optimize the structure of a μ-opioid receptor ligand, analogs H-Tyr-c[D-Lys-Xxx-Tyr-Gly] were synthesized and their biological activity was tested. The analog containing a Phe(3) was identified as not only exhibiting binding affinity 14-fold higher than the original hit but also producing agonist activity 3-fold more potent than morphine. NMR study suggested that a trans conformation at D-Lys(2)-Xxx(3) is crucial for these cyclic peptides to maintain high affinity, selectivity, and functional activity toward the μ-opioid receptor.

The hypothesis in the current study is that the simultaneous direct in vivo testing of thousands to millions of systematically arranged mixture-based libraries will facilitate the identification of enhanced individual compounds. Individual compounds identified from such libraries may have increased specificity and decreased side effects early in the discovery phase. Testing began by screening ten diverse scaffolds as single mixtures (ranging from 17 340 to 4 879 681 compounds) for analgesia directly in the mouse tail withdrawal model. The “all X” mixture representing the library TPI-1954 was found to produce significant antinociception and lacked respiratory depression and hyperlocomotor effects using the Comprehensive Laboratory Animal Monitoring System (CLAMS). The TPI-1954 library is a pyrrolidine bis-piperazine and totals 738 192 compounds. This library has 26 functionalities at the first three positions of diversity made up of 28 392 compounds each (26 × 26 × 42) and 42 functionalities at the fourth made up of 19 915 compounds each (26 × 26 × 26). The 120 resulting mixtures representing each of the variable four positions were screened directly in vivo in the mouse 55 °C warm-water tail-withdrawal assay (ip administration). The 120 samples were then ranked in terms of their antinociceptive activity. The synthesis of 54 individual compounds was then carried out. Nine of the individual compounds produced dose-dependent antinociception equivalent to morphine. In practical terms what this means is that one would not expect multiexponential increases in activity as we move from the all-X mixture, to the positional scanning libraries, to the individual compounds. Actually because of the systematic formatting one would typically anticipate steady increases in activity as the complexity of the mixtures is reduced. This is in fact what we see in the current study. One of the final individual compounds identified, TPI 2213-17, lacked significant respiratory depression, locomotor impairment, or sedation. Our results represent an example of this unique approach for screening large mixture-based libraries directly in vivo to rapidly identify individual compounds.

A novel series of endomorphin-1 (EM-1) and endomorphin-2 (EM-2) analogues was synthesized, incorporating chiral α-hydroxy-β-phenylalanine (AHPBA), and/or Dmt(1)-Tic(2) at different positions. Pharmacological activity and metabolic stability of the series was assessed. Consistent with earlier studies of β-amino acid substitution into endomorphins, multiple analogues incorporation AHPBA displayed high affinity for μ and δ opioid receptors (MOR and DOR, respectively) in radioligand competition binding assays, and an increased stability in rat brain membrane homogenates, notably Dmt-Tic-(2R,3S)AHPBA-Phe-NH2 (compound 26). Intracerebroventricular (i.c.v.) administration of 26 produced antinociception (ED50 value (and 95% confidence interval) = 1.98 (0.79-4.15) nmol, i.c.v.) in the mouse 55 °C warm-water tail-withdrawal assay, equivalent to morphine (2.35 (1.13-5.03) nmol, i.c.v.), but demonstrated DOR-selective antagonism in addition to non-selective opioid agonism. The antinociception of 26 was without locomotor activity or acute antinociceptive tolerance. This novel class of peptides adds to the potentially therapeutically relevant collection of previously reported EM analogues.

The Major Histocompatibility Complex (MHC) is a critical element in mounting an effective immune response in vertebrates against invading pathogens. Studies of MHC in wildlife populations have typically focused on assessing diversity within the peptide binding regions (PBR) of the MHC class II (MHC II) family, especially the DQ receptor genes. Such metrics of diversity, however, are of limited use to health risk assessment since functional analyses (where changes in the PBR are correlated to recognition/pathologies of known pathogen proteins), are difficult to conduct in wildlife species. Here we describe a means to predict the binding preferences of MHC proteins: We have developed a model positional scanning library analysis (MPSLA) by harnessing the power of mixture based combinatorial libraries to probe the peptide landscapes of distinct MHC II DQ proteins. The algorithm provided by NNAlign was employed to predict the binding affinities of sets of peptides generated for DQ proteins. These binding affinities were then used to retroactively construct a model Positional Scanning Library screen. To test the utility of the approach, a model screen was compared to physical combinatorial screens for human MHC II DP. Model library screens were generated for DQ proteins derived from sequence data from bottlenose dolphins from the Indian River Lagoon (IRL) and the Atlantic coast of Florida, and compared to screens of DQ proteins from Genbank for dolphin and three other cetaceans. To explore the peptide binding landscape for DQ proteins from the IRL, combinations of the amino acids identified as active were compiled into peptide sequence lists that were used to mine databases for representation in known proteins. The frequency of which peptide sequences predicted to bind the MHC protein are found in proteins from pathogens associated with marine mammals was found to be significant (p values

Mixture-based combinatorial libraries were first described in the early 1990s and have since been used in a wide array of assay formats in many laboratories. These libraries allow thousands of compounds to be prepared and screened at a fraction of the time and cost required for individual compound arrays. Mixture-based libraries are synthesized on solid phase, but screened in solution. Peptides were the natural choice for the first combinatorial chemists, as they provided a sufficient variety of side chains to create a large diversity (20 l-amino acids), solid phase synthesis is performed in a linear fashion, and chemical reactions had already been pre-optimized. Additionally, short peptides with biological activity were available to demonstrate the power of the emerging libraries in screening assays. The introduction of mathematical theory and computational analyses combined with a program for dissemination of the libraries will influence of mixtures-based drug peptide discovery in the coming years.

A positional scanning cyclic peptide library was generated using a penta-peptide thioester scaffold. Glycine was fixed at position R(1). Diaminopropionic acid was fixed at position R(3), with its γ-amino attaching to an anthraniloyl group. Positions R(2) and R(4) contained 36 L- and D- amino acids and position R(5) contained 19 L- amino acids. Cyclization was performed in a mixture of acetonitrile and 1.5 M aqueous imidazole solution (7:1 v/v) at room temperature for 5 days. No significant cross-oligomerization was detected under the cyclization conditions. The library was screened in a binding assay for mu opioid receptor, identifying the active amino acid mixture at each position. A total of 40 individual cyclic peptides were identified and synthesized by the combinations of the most active amino acid mixtures found at three positions 5 × 4 × 2. Two cyclic peptides exhibited high binding affinities to opioid receptor. The most active cyclic peptide in the library was yielded to have Tyr at R(2), D-Lys at R(4), and Tyr at R(5). Further investigation on this compound revealed the side chain-to-tail isomer to have greater binding affinity (14 nM) than the head-to-tail isomer (39 nM). Both isomers were selective for the mu-opioid receptor.

The use of the harmonic mean model for predicting the activities of a given mixture and its constituents has not previously been explored in the context of combinatorial libraries and drug discovery. Herein, the analyses of historical data confirm the harmonic mean as an accurate predictor of mixture activity. The implications of these results are discussed.

Mixture-based synthetic combinatorial library (MB-SCL) screening is a well-established experimental approach for rapidly retrieving structure-activity relationships (SAR) and identifying hits. Virtual screening is also a powerful approach that is increasingly being used in drug discovery programs and has a growing number of successful applications. However, limited efforts have been made to integrate both techniques. To this end, we combined experimental data from a MB-SCL of bicyclic guanidines screened against the κ-opioid receptor and molecular similarity methods. The activity data and similarity analyses were integrated in a biometric analysis-similarity map. Such a map allows the molecules to be categorized as actives, activity cliffs, low similarity to the reference compounds, or missed hits. A compound with IC(50) = 309 nM was found in the "missed hits" region, showing that active compounds can be retrieved from a MS-SCL via computational approaches. The strategy presented in this work is general and is envisioned as a general-purpose approach that can be applied to other MB-SCLs.

Synthetic combinatorial methods now make it practical to readily produce hundreds of thousands of individual compounds, but it is clearly impractical to screen each separately in vivo. We theorized that the direct in vivo testing of mixture-based combinatorial libraries during the discovery phase would enable the identification of novel individual compounds with desirable antinociceptive profiles while simultaneously eliminating many compounds with poor absorption, distribution, metabolism, or pharmacokinetic properties. The TPI 1346 small-molecule combinatorial library is grouped in 120 mixtures derived from 26 functionalities at the first three positions and 42 functionalities at the fourth position of a pyrrolidine bis-cyclic guanidine core scaffold, totaling 738,192 compounds. These 120 mixtures were screened in vivo using the mouse 55 degrees C warm water tail-withdrawal assay to identify mixtures producing antinociception. From these data, two fully defined individual compounds (TPI 1818-101 and TPI 1818-109) were synthesized. These were examined for antinociceptive, respiratory, locomotor, and conditioned place preference effects. The tail-withdrawal assay consistently demonstrated distinctly active mixtures with analgesic activity that was blocked by pretreatment with the non-selective opioid antagonist, naloxone. Based on these results, synthesis and testing of TPI 1818-101 and 1818-109 demonstrated a dose-dependent antinociceptive effect three to five times greater than morphine that was antagonized by mu- or mu- and kappa-opioid receptor selective antagonists, respectively. Neither 1818-101 nor 1818-109 produced significant respiratory depression, hyperlocomotion, or conditioned place preference. Large, highly diverse mixture-based libraries can be screened directly in vivo to identify individual compounds, potentially accelerating the development of promising therapeutics.

Conformation of bicyclic guanidines with kappa-opioid receptor activity derived in our laboratory from a positional scanning synthetic combinatorial library is presented in this work. We propose a common bioactive conformation and putative pharmacophoric features by means of 3D similarity methods. Our ‘Y’ shape molecular binding model explains structure–activity relationships and suggests that the guanidine functionality and a 4-methoxybenzyl group may be involved in key interactions with the receptor. Comparison of our model with known opiates suggest a similar binding mode showing that the bicyclic guanidines presented in this work are suitable scaffolds for further development of new opioid receptors ligands.

Interleukins 12 and 23 have important roles in the pathophysiology of psoriasis. We assessed ustekinumab, a human monoclonal antibody directed against these cytokines, for the treatment of psoriasis.In this phase III, parallel, double-blind, placebo-controlled study, 766 patients with moderate-to-severe psoriasis were randomly assigned to receive ustekinumab 45 mg (n=255) or 90 mg (n=256) at weeks 0 and 4 and then every 12 weeks; or placebo (n=255) at weeks 0 and 4, with subsequent crossover to ustekinumab at week 12. Patients who were initially randomised to receive ustekinumab at week 0 who achieved long-term response (at least 75% improvement in psoriasis area and severity index [PASI 75] at weeks 28 and 40) were re-randomised at week 40 to maintenance ustekinumab or withdrawal from treatment until loss of response. Both randomisations were done with a minimisation method via a centralised interactive voice response system. The primary endpoint was the proportion of patients achieving PASI 75 at week 12. Analyses were by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00267969.All randomised patients were included in the efficacy analysis. 171 (67.1%) patients receiving ustekinumab 45 mg, 170 (66.4%) receiving ustekinumab 90 mg, and eight (3.1%) receiving placebo achieved PASI 75 at week 12 (difference in response rate vs placebo 63.9%, 95% CI 57.8-70.1, p0.0001 for 45 mg and 63.3%, 57.1-69.4, p0.0001 for 90 mg). At week 40, long-term response had been achieved by 150 patients in the 45 mg group and 172 patients in the 90 mg group. Of these, 162 patients were randomly assigned to maintenance ustekinumab and 160 to withdrawal. PASI 75 response was better maintained to at least 1 year in those receiving maintenance ustekinumab than in those withdrawn from treatment at week 40 (p0.0001 by log-rank test). During the placebo-controlled phase, adverse events occurred in 278 (54.5%) of the 510 patients receiving ustekinumab and 123 (48.2%) of the 255 receiving placebo. Serious adverse events occurred in six (1.2%) of 510 patients receiving ustekinumab and in two (0.8%) of 255 receiving placebo in this phase. The pattern of adverse events was much the same in the placebo crossover and randomised withdrawal phases as it was in the placebo-controlled phase.Ustekinumab seems to be efficacious for the treatment of moderate-to-severe psoriasis; dosing every 12 weeks maintains efficacy for at least a year in most patients.

The generation of chiral polyamine libraries has been successfully accomplished in our laboratory following exhaustive reduction of resin-bound peptides. Herein, we report the synthesis and screening results of a positional scanning mixture-based library of chiral hepta-amines in a radioreceptor assay for the opioid receptor. The positional scanning hepta-amine library was generated by the exhaustive reduction of a library of 34,012,070 hexapeptides. Following screening of the entire library, combinations of the most active functionalities found at each position were used to synthesize and screen 40 individual hepta-amines and served as starting ‘hits’ for further SAR studies. The individual compounds showed IC 50 values ranging from 14 to 345 nM. As might be anticipated by the known studies of μ opiate antagonists, the identified active hepta-amines possessed aromatic rings derived from phenylalanine and tyrosine amino acid side chains. Following SAR studies, a truncation analog, reduced and permethylated YYF-NH 2 , was found to be highly active (0.5 nM) as a selective μ antagonist in the guinea pig ileum bioassay.

To evaluate the effect of infliximab on health related quality of life (HRQoL) and physical function in patients with active psoriatic arthritis (PsA) in the IMPACT 2 trial.200 patients with PsA unresponsive to conventional treatment were randomised to intravenous infusions of infliximab 5 mg/kg or placebo at weeks 0, 2, 6, 14, and 22; patients with inadequate response entered early escape at week 16. HRQoL was assessed using the Short Form-36 (SF-36) at weeks 0, 14, and 24. Functional disability was assessed using the Health Assessment Questionnaire (HAQ) at every visit through week 24. Associations between changes in quality of life (SF-36) and articular (American College of Rheumatology (ACR)) and dermatological (Psoriasis Area and Severity Index (PASI)) responses were examined.Mean percentage improvement from baseline in HAQ was 48.6% in the infliximab group compared with worsening of 18.4% in the placebo group at week 14 (p0.001). Furthermore, 58.6% and 19.4% of infliximab and placebo treated patients, respectively, achieved a clinically meaningful improvement in HAQ (that is,or = 0.3 unit decrease) at week 14 (p0.001). Increases in physical and mental component summary (PCS and MCS) scores and all eight scales of the SF-36 in the infliximab group were greater than those in the placebo group at week 14 (por = 0.001). These benefits were sustained through week 24. Patients achieving ACR20 and PASI75 responses had the greatest improvements in PCS and MCS scores.In patients with PsA, infliximab 5 mg/kg significantly improved HRQoL and physical function compared with placebo through 24 weeks.

Summary Background Psoriasis has a well-documented, markedly negative effect on patient quality of life. Objectives To evaluate the impact of long-term infliximab maintenance therapy on health-related quality of life (HRQoL) in patients with psoriasis. Methods The Dermatology Life Quality Index (DLQI) and 36-item Short Form Health Survey (SF-36) were administered as part of the pivotal double-blind, placebo-controlled efficacy and safety EXPRESS study of infliximab in chronic plaque psoriasis. In total, 378 patients with moderate-to-severe psoriasis were enrolled at 32 centres in Europe and Canada. Patients were randomized to receive either placebo or infliximab 5 mg kg−1 induction at weeks 0, 2 and 6 followed by maintenance every 8 weeks; placebo patients crossed over at week 24 to receive the infliximab induction and maintenance regimen. Results At week 10, infliximab-treated patients had significantly greater improvement in DLQI scores (P

Summary Background Psoriasis is a chronic disease that significantly diminishes the health-related quality of life (HRQOL). Infliximab is a chimeric, tumour necrosis factor α monoclonal antibody that has been shown to improve the signs and symptoms of plaque psoriasis. Objectives The objective of this study was to evaluate the effect of infliximab induction therapy on the HRQOL of patients with severe plaque psoriasis. Methods In this double-blind, placebo-controlled trial, 249 patients were randomly assigned to receive intravenous infusions of 3 or 5 mg kg−1 of infliximab or placebo and were treated at weeks 0, 2 and 6. Patients completed the Dermatology Life Quality Index (DLQI) at baseline and week 10. Results Infliximab induction therapy resulted in a substantial improvement in HRQOL. At week 10, patients in the infliximab 3- and 5-mg kg−1 groups showed a median percentage improvement in DLQI scores of 84·0% and 91·0%, respectively, compared with 0% in the placebo group (P

The parallel synthesis of bis-oxazole peptidomimetics starting from Boc-aminoacids and Serine-methyl ester is described. This work presents the synthesis of oxazole aminoacid building blocks in solution phase and their utilization for the solid phase peptide synthesis of a library of diverse bis-oxazole peptidomimetics in good overall yields.

Tumor necrosis factor-alpha is a key mediator in the pathogenesis of psoriasis. Infliximab is a monoclonal antibody that specifically binds to tumor necrosis factor-alpha, blocking its biologic activity.The purpose of this study was to access the efficacy and safety of infliximab induction therapy for patients with severe plaque psoriasis.In this multicenter, double-blind, placebo-controlled trial, 249 patients with severe plaque psoriasis were randomly assigned to receive intravenous infusions of either 3 or 5 mg/kg of infliximab or placebo given at weeks 0, 2, and 6. The primary end point was the proportion of patients who achieved at least 75% improvement in Psoriasis Area and Severity Index score from baseline at week 10. At week 26, patients whose Physician Global Assessment indicated moderate or severe disease were eligible for a single intravenous infusion of their assigned treatment to assess the safety of retreatment after a 20-week, treatment-free interval.At week 10, 72% of patients treated with infliximab (3 mg/kg) and 88% of patients treated with infliximab (5 mg/kg) achieved a 75% or greater improvement from baseline in Psoriasis Area and Severity Index score compared with 6% of patients treated with placebo (P.001). Improvement was observed in both infliximab groups as early as 2 weeks. Overall, 63%, 78%, and 79% of patients in the placebo, 3-, and 5-mg/kg groups, respectively, reported one or more adverse events.Infliximab treatment resulted in a rapid and significant improvement in the signs and symptoms of psoriasis. Infliximab was generally well tolerated.

Changes in the redox equilibrium of cells influence a host of cell functions. Alterations in the redox equilibrium are precipitated by changing either the glutathione/glutathione-disulfide ratio (GSH/GSSG) and/or the reduced/oxidized thioredoxin ratio. Redox-sensitive green fluorescent proteins (GFP) allow real time visualization of the oxidation state of the indicator. Ratios of fluorescence from excitation at 400 and 490 nm indicate the extent of oxidation and thus the redox potential while canceling out the amount of indicator and the absolute optical sensitivity. Because the indicator is genetically encoded, it can be targeted to specific proteins or organelles of interest and expressed in a wide variety of cells and organisms. We evaluated roGFP1 (GFP with mutations C48S, S147C, and Q204C) and roGFP2 (the same plus S65T) with physiologically or toxicologically relevant oxidants both in vitro and in living mammalian cells. Furthermore, we investigated the response of the redox probes under physiological redox changes during superoxide bursts in macrophage cells, hyperoxic and hypoxic conditions, and in responses to H(2)O(2)-stimulating agents, e.g. epidermal growth factor and lysophosphatidic acid.

Highly active fluorescent compounds having kappa opioid activity were identified following the screening in a kappa-specific radioligand binding assay of a positional scanning tetrapeptide combinatorial library in which every tetrapeptide was fluorescently labeled. Lissamine rhodamine B sulfonyl chloride was coupled to the N terminal of a mixture-based tetrapeptide positional scanning library made up of over 7.3 million tetrapeptides. Upon determination of the most active mixtures for each position of the library in the kappa binding assay, individual rhodamine labeled tetrapeptides were then synthesized and tested to determine their activities. Eight individual rhodamine labeled peptides were identified that were specific for the kappa opioid receptor, having binding affinities ranging from 5-20 nM. These peptides were poor inhibitors at the mu and delta receptors (K(i)>5,000 nM). Furthermore, neither rhodamine itself nor these same tetrapeptides lacking the N-terminal rhodamine had any significant activity at the kappa receptor, indicating that both the tetrapeptide sequence and the rhodamine moiety are required for receptor binding. This study has demonstrated that novel fluorescent compounds with intrinsic activity can be identified through the use of combinatorial chemistry.

Compatibility of PVC with liquid alkyltin alkylthioglycolate stabilizers was studied by thermal methods, including isothermal calorimetry of mixing, DSC, DMA, and dielectric relaxation. The enthalpy of mixing of PVC with the series of alkyltin alkyl thioglycolates was measured over the entire concentration range at ambient conditions. It was found that all tested compounds are compatible with PVC in a broad concentration range and form homogeneous mixtures. The results are discussed in terms of the superposition of glassy state and molecular interaction contributions to the enthalpy of mixing of the glassy polymer with liquid additives. The influence of organotin stabilizers on the glassy structure of PVC films was studied by means of DSC and the dielectric relaxation spectrum. The enhancement of the glassy structure of PVC by alkyltin alkyl thioglycolates is interpreted as the result of strong multi-site molecular complexes between organotin molecules and PVC chains, which act as additional clips in the entanglement network of polymer chains.

Objective: Infliximab monotherapy provided a rapid and high degree of clinical benefit in patients with moderate to severe psoriasis in a previously conducted trial. Herein we describe the pharmacodynamic and pharmacokinetic results observed in this clinical trial. Methods: Patients with psoriasis received 5 or 10 mg/kg of infliximab or placebo at weeks 0, 2, and 6. Immunohistochemical analysis of lesional (weeks 0, 2, 10) and nonlesional (week 0) biopsies was conducted. Median infliximab half-life and peak serum concentrations over time were calculated. Results: Infliximab immunotherapy resulted in rapid and dramatic decreases in epidermal inflammation and normalization of keratinocyte differentiation in psoriatic plaques; these changes preceded maximal clinical response. Infliximab concentrations were maintained above the detection limit (0.1 mg/mL) in the majority of patients through week 14. Conclusion: The clinical and immunohistologic data demonstrate a pivotal role for tumor necrosis factor-α in the pathogenesis of psoriasis and support further development of drugs targeting tumor necrosis factor-α. (J Am Acad Dermatol 2003;48:68-75.)

We report the design and the parallel solid phase synthesis of linear and oligoheterocyclic peptidomimetic analogs of Leu-enkephalin. The described peptidomimetics represent different unique scaffolds that distribute in the space the peptidyl side chains of amino acids essential for biological activity and mimic the bioactive conformation of the Leu-enkephalin peptide. All the compounds were screened in competitive radioligand binding assays to determine their affinities for μ-(MOR), and κ-(KOR) opioid receptors. A reduced analog of Leu-enkephalin TPI1879-26 with activity Ki=60 nM for the mu receptor was identified.

Summary Background Currently available treatments for moderate to severe psoriasis are either incompletely effective in some patients, or are associated with toxic effects. Since tumour necrosis factor α (TNF-α) is thought to have a role in the pathogenesis of psoriasis, we did a double-blind, randomised trial to assess the clinical benefit and safety of infliximab-a monoclonal antibody against TNF-α. Methods 33 patients with moderate to severe plaque psoriasis were randomly assigned intravenous placebo (n=11), infliximab 5 mg/kg (n=11), or infliximab 10 mg/kg (n=11) at weeks 0, 2, and 6. Patients were assessed at week 10 for the primary endpoint (score on the physician's global assessment [PGA]). Analysis was by intention to treat. Findings Of the 33 patients enrolled, three dropped out. Nine of 11 (82%) patients in the infliximab 5 mg/kg group were responders (good, excellent, or clear rating on PGA), compared with two of 11 (18%) in the placebo group (difference 64% [95% CI 20–89], p=0·0089), and ten of 11 (91%) patients in the infliximab 10 mg/kg group were responders (difference from placebo 73% [30-94], p=0·0019). The median time to response was 4 weeks for patients in both infliximab groups. There were no serious adverse events, and infliximab was well tolerated. Interpretation In this controlled trial, patients receiving the anti-TNF-α agent infliximab as monotherapy experienced a high degree of clinical benefit and rapid time to response in the treatment of moderate to severe plaque psoriasis compared with patients who received placebo. These findings suggest that TNF-α has a pivotal role in the pathogenesis of psoriasis.

Weibull parameters extracted from tests of 75 mm Kevlar bundles by Fourier deconvolution produced average Weibull parameters of ma 22:2 and 10a 0:0284; which indicate that filament interactions concentrated the failures over a smaller range of strain. A bundle with filaments varying from 75 to 76.1 mm in length failed with a load‐displacement energy 14% higher than found with uniform filament length. Weibull parameters of ma 12:3 and 10a 0:0305 indicate that filament interactions were reduced and parameters corresponding to single filament testing were obtained rapidly. q 2000 Published by Elsevier Science Ltd.