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Older adults have been statistically proved to be at a higher risk of getting severely infected by the coronavirus COVID-19, evoking sweeping narratives of compassionate ageism surrounding them in different discourses. By analysing the media content, scholars from different areas have alerted us about the amplified ageism aroused by the pandemic crisis. However, we are still short of empirical evidence to learn how ageism is constructed in diverse sociocultural contexts in the wake of this global pandemic crisis. This study provides the case of Hong Kong to reflect on how ageism, as a set of social inequalities, is constructed. By examining 814 articles collected from the three most popular newspapers with different political orientations in Hong Kong, this study uses quantitative and qualitative content analysis to examine how older people have been generally represented. Then it further compares how these representations have been influenced by the media's liberal or conservative preferences. Third, it examines the relationship between the political orientation of newspapers and how different forms of ageism are constructed. The findings indicate that despite the liberal or conservative inclination of the three newspapers, they portray the older population as frail, dependent and deprived not only at the biomedical level but in all aspects of life. This study also reveals that the newspapers with a populist inclination in both camps have shown more hostile attitudes in representing compassionate ageism. In contrast, liberal and conservative-leaning media affirmed the government's dominant role in taking full responsibility for caring for the older population. The findings indicate that the polarised ageism frame cannot fully explain the underpinnings of ageism and implied policy processing in different contexts.

Background Obesity is an established risk factor for severe COVID-19 outcomes. The mechanistic underpinnings of this association are not well-understood. Objective To evaluate the mediating role of systemic inflammation in obesity-associated COVID-19 outcomes. Methods This hospital-based, observational study included 3828 SARS-CoV-2-infected patients who were hospitalized February to May 2020 at Massachusetts General Hospital (MGH) or Columbia University Irving Medical Center/New York Presbyterian Hospital (CUIMC/NYP). We use mediation analysis to evaluate whether peak inflammatory biomarkers (C-reactive protein [CRP], erythrocyte sedimentation rate [ESR], D-dimer, ferritin, white blood cell count and interleukin-6) are in the causal pathway between obesity (BMI ≥ 30) and mechanical ventilation or death within 28 days of presentation to care. Results In the MGH cohort (n = 1202), obesity was associated with greater likelihood of ventilation or death (OR = 1.73; 95% CI = [1.25, 2.41]; P = 0.001) and higher peak CRP (P Conclusion Findings support systemic inflammatory pathways in obesity-associated severe COVID-19 disease, particularly in patients

OBJECTIVE Children with autism spectrum disorder (ASD) have difficulty participating in dental care and experience significant unmet dental needs. We examined the efficacy of parent training (PT) for improving oral hygiene and oral health in underserved children with ASD. METHOD Families of Medicaid-eligible children with ASD (ages 3–13 years, 85% boys, 62% with intellectual disability) reporting difficulty with dental care participated in a 6-month randomized controlled trial comparing PT (n = 60) with a psychoeducational dental toolkit (n = 59). Primary outcomes were parent-reported frequency of twice-daily toothbrushing and dentist-rated visible plaque. Secondary outcomes included parent-reported child behavior problems during home oral hygiene and dentist-rated caries. Dentists were blind to intervention assignment. Analyses were intention to treat. RESULTS Retention was high at posttreatment (3 months, 93%) and 6-month follow-up (90%). Compared with the toolkit intervention, PT was associated with increased twice-daily toothbrushing at 3 (78% vs 55%, respectively; P < .001) and 6 (78% vs 62%; P = .002) months and a reduction in plaque at 3 months (intervention effect, −0.19; 95% confidence interval [CI], −0.36 to −0.02; P = .03) and child problem behaviors at 3 (−0.90; 95% CI, −1.52 to −0.28; P = .005) and 6 (−0.77; 95% CI, −1.39 to −0.14; P = .02) months. Comparatively fewer caries developed in children receiving the PT intervention over 3 months (ratio of rate ratios, 0.73; 95% CI, 0.54 to 0.99; P = .04). CONCLUSIONS PT represents a promising approach for improving oral hygiene and oral health in underserved children with ASD at risk for dental problems.

We examined racial and ethnic differences in the prevalence of behavioral problems measured by the Child Behavioral Checklist (CBCL), sleep disturbances measured by the Child Sleep Habits Questionnaire (CSHQ), and medication use among children with Autism Spectrum Disorders (ASD). We analyzed data from the Autism Treatment Network (ATN) dataset for 2,576 children ages 6 to 18 years of age diagnosed with ASD. Multivariable logistic regression accounting for age, gender, Diagnostic and Statistical Manual of Mental Disorders (4th Edition – Text Revision), diagnosis (Autistic Disorder, PDD-NOS, Asperger's Disorder), and parents' education did not show any racial or ethnic differences in behavioral challenges, conduct problems, or sleep disturbances for any of the groups, but Black children had lower odds of Total Problem Behaviors and Asian children had lower odds of Hyperactivity compared to White children. As a group, children from racial and ethnic minorities had lower odds of Total Problem Behaviors and Conduct Problems compared to White children. Hispanic children had lower odds of medication use for Behavioral Challenges, Total Problem Behaviors, Hyperactivity, and Conduct Problems. Asian children had lower odds of medication use for Behavioral Challenges, Total Problem Behaviors, and Hyperactivity; and had close to lower odds in medication use for Conduct Problems. Black children had lower odds for medication use for Total Problem Behaviors only. As a group, children from racial and ethnic minorities had lower odds for medication use for Behavioral Challenges, Total Problem Behaviors, Hyperactivity, and Conduct problems, but not for Sleep Disturbances. While these results are consistent with previous studies showing that White children are significantly more likely to receive psychotropic medication compared to children from racial and ethnic minority groups, we found no such differences for sleep challenges, suggesting that they are more consistently identified and equitably treated than other behavioral problems associated with ASD. We draw upon Andersen's (1995) Behavioral Model of Healthcare Use to suggest predisposing, enabling, and needs factors that may contribute to this pattern of racial and ethnic differences in the use of medications among children ASD.

BACKGROUND Adolescents and young adults (AYA) with HIV experience poorer health outcomes compared with adults. To improve care for AYA with HIV, information about patterns of costly health care resource utilization is needed. METHODS Among 13-30 year olds in the US HIV Research Network, we stratified outpatient visits, emergency department (ED) visits, and inpatient days/person-year (PY) by HIV acquisition model [perinatal (PHIVY) and nonperinatal (NPHIVY)], age (13-17, 18-23, and 24-30 years), CD4 strata (

Introduction: The use of online platforms for pediatric healthcare research is timely, given the current pandemic. These platforms facilitate trial efficiency integration including electronic consent, randomization, collection of patient/family survey data, delivery of an intervention, and basic data analysis. Methods: We created an online digital platform for a multicenter study that delivered an intervention for sleep disorders to parents of children with autism spectrum disorder (ASD). An advisory parent group provided input. Participants were randomized to receive either a sleep education pamphlet only or the sleep education pamphlet plus three quick-tips sheets and two videos that reinforced the material in the pamphlet (multimedia materials). Three measures – Family Inventory of Sleep Habits (FISH), Children’s Sleep Habits Questionnaire modified for ASD (CSHQ-ASD), and Parenting Sense of Competence (PSOC) – were completed before and after 12 weeks of sleep education. Results: Enrollment exceeded recruitment goals. Trial efficiency was improved, especially in data entry and automatic notification of participants related to survey completion. Most families commented favorably on the study. While study measures did not improve with treatment in either group (pamphlet or multimedia materials), parents reporting an improvement of ≥3 points in the FISH score showed a significantly improved change in the total CSHQ (P = 0.038). Conclusion: Our study demonstrates the feasibility of using online research delivery platforms to support studies in ASD, and more broadly, pediatric clinical and translational research. Online platforms may increase participant inclusion in enrollment and increase convenience and safety for participants and study personnel.

Objective To evaluate differences by race/ethnicity in clinical characteristics and outcomes among hospitalized patients with Covid-19 at Massachusetts General Hospital (MGH). Methods The MGH Covid-19 Registry includes confirmed SARS-CoV-2-infected patients hospitalized at MGH and is based on manual chart reviews and data extraction from electronic health records (EHRs). We evaluated differences between White/Non-Hispanic and Hispanic patients in demographics, complications and 14-day outcomes among the N = 866 patients hospitalized with Covid-19 from March 11, 2020—May 4, 2020. Results Overall, 43% of patients hospitalized with Covid-19 were women, median age was 60.4 [IQR = (48.2, 75)], 11.3% were Black/non-Hispanic and 35.2% were Hispanic. Hispanic patients, representing 35.2% of patients, were younger than White/non-Hispanic patients [median age 51y; IQR = (40.6, 61.6) versus 72y; (58.0, 81.7) (p Conclusions Hospitalized Hispanic patients were younger and had fewer comorbidities compared to White/non-Hispanic patients; despite comparable rates of ICU care or death, a greater proportion recovered. These results have implications for public health policy and the design and conduct of clinical trials.

BACKGROUND AND OBJECTIVES: Children with autism spectrum disorder (ASD) have a higher prevalence of epilepsy compared with general populations. In this pilot study, we prospectively identified baseline risk factors for the development of seizures in individuals with ASD and also identified characteristics sensitive to seizure onset up to 6 years after enrollment in the Autism Speaks Autism Treatment Network. METHODS: Children with ASD and no history of seizures at baseline who either experienced onset of seizures after enrollment in the Autism Treatment Network or remained seizure free were included in the analysis. RESULTS: Among 472 qualifying children, 22 (4.7%) experienced onset of seizures after enrollment. Individuals who developed seizures after enrollment exhibited lower scores at baseline on all domains of the Vineland Adaptive Behavior Scales, greater hyperactivity on the Aberrant Behavior Checklist (25.4 ± 11.8 vs 19.2 ± 11.1; P = .018), and lower physical quality of life scores on the Pediatric Quality of Life Inventory (60.1 ± 24.2 vs 76.0 ± 18.2; P < .001). Comparing change in scores from entry to call-back, adjusting for age, sex, length of follow-up, and baseline Vineland II composite score, individuals who developed seizures experienced declines in daily living skills (−8.38; 95% confidence interval −14.50 to −2.50; P = .005). Adjusting for baseline age, sex, and length of follow-up, baseline Vineland II composite score was predictive of seizure development (risk ratio = 0.95 per unit Vineland II composite score, 95% confidence interval 0.92 to 0.99; P = .007). CONCLUSIONS: Individuals with ASD at risk for seizures exhibited changes in adaptive functioning and behavior.

The newest edition of the Diagnostic and Statistical Manual of Mental Disorders (5th ed., DSM-5) introduced substantial changes to the diagnostic criteria for autism spectrum disorder, including new severity level ratings for social communication and restricted and repetitive behavior domains. The purpose of this study was to evaluate the use of these new severity ratings and to examine their relation to other measures of severity and clinical features. Participants included 248 children with autism spectrum disorder who received diagnostic evaluations at one of six Autism Treatment Network sites. Higher severity ratings in both domains were associated with younger age, lower intelligence quotient, and greater Autism Diagnostic Observation Schedule–Second Edition domain-specific symptom severity. Greater restricted and repetitive behavior severity was associated with higher parent-reported stereotyped behaviors. Severity ratings were not associated with emotional or behavioral problems. The new DSM-5 severity ratings in both domains were significantly associated with behavioral observations of autism severity but not with measures of other behavioral or emotional symptoms. However, the strong associations between intelligence quotient and DSM-5 severity ratings in both domains suggest that clinicians may be including cognitive functioning in their overall determination of severity. Further research is needed to examine clinician decision-making and interpretation of these specifiers.

Multiple therapeutic opportunities have been suggested for compounds capable of selective activation of metabotropic glutamate 3 (mGlu3) receptors, but small molecule tools are lacking. As part of our ongoing efforts to identify potent, selective, and systemically bioavailable agonists for mGlu2 and mGlu3 receptor subtypes, a series of C4β-N-linked variants of (1S,2S,5R,6S)-2-amino-bicyclo[3.1.0]hexane-2,6-dicarboxylic acid 1 (LY354740) were prepared and evaluated for both mGlu2 and mGlu3 receptor binding affinity and functional cellular responses. From this investigation we identified (1S,2S,4S,5R,6S)-2-amino-4-[(3-methoxybenzoyl)amino]bicyclo[3.1.0]hexane-2,6-dicarboxylic acid 8p (LY2794193), a molecule that demonstrates remarkable mGlu3 receptor selectivity. Crystallization of 8p with the amino terminal domain of hmGlu3 revealed critical binding interactions for this ligand with residues adjacent to the glutamate binding site, while pharmacokinetic assessment of 8p combined with its effect in an mGlu2 ...

To learn more about the long-term consequences of displacement on women, we examine the marriage market outcomes of forcibly displaced women. Using data from 12 representative surveys in 7 countries, we document that women who are adolescents at the time of displacement are more likely to be married. This pattern is robust to choice of comparison group and across countries. We do not find this pattern for displaced adolescent men. We provide additional evidence on this relationship by using unique features of the partition of India in 1947, an event which resulted in large-scale bilateral displacement between India and newly formed Pakistan. Specifically, we use the plausibly exogenous timing and the arbitrary nature of the border drawing to motivate a difference-in-difference design. Using a representative household survey collected in 1973, we find that women who were adolescents when they were displaced by partition were significantly more likely to marry earlier, in line with the descriptive cross country evidence. These women were less likely to continue their education and had more children overall, but do not appear to have married spouses with worse observable characteristics.

This study aims to explore the elderly people’s knowledge, attitude, and understandings toward financial management, and how they behave in using IT-supported financial services. Mixed methodologies, including quantitative street survey and qualitative focus group interviews, are used. The result shows an active involvement with investment market of the mature segments despite claiming safe and stable returns as the paramount principle of asset management. They also have a substantial knowledge on some of the technological-enabled financial services, particularly the younger groups (age 50-59). Cybersecurity is their major concern and barrier on whether to use them or not. Besides, their value and behaviors of buying mature adult financial products should be understood within a context of traditional family culture value. Based on the above analysis, the elderly can be categorized into three major types in using IT-supported financial products and services, including proactive users, passive followers and hard opposition. On the one hand, this research breaks up the outdated stereotype of technology use among elderly people; on the other hand, aged people are facing the challenges of cognitive and physical decline led by ageing. As such, it is essential to conduct specific financial literacy intervention. This project brings new insights into the financial education which is appropriate to the elderly.

The transition from DSM-IV to DSM-5 criteria for autism spectrum disorder (ASD) sparked considerable concern about the potential implications of these changes. This study was designed to address limitations of prior studies by prospectively examining the concordance of DSM-IV and final DSM-5 criteria on a consecutive sample of 439 children referred for autism diagnostic evaluations. Concordance and discordance were assessed using a consistent diagnostic battery. DSM-5 criteria demonstrated excellent overall specificity and good sensitivity relative to DSM-IV criteria. Sensitivity and specificity were strongest for children meeting DSM-IV criteria for autistic disorder, but poor for those meeting criteria for Asperger's disorder and pervasive developmental disorder. Higher IQ, older age, female sex, and less pronounced ASD symptoms were associated with greater discordance.

In children with autism spectrum disorder, there have been equivocal results regarding primary caregiver education level and its influence on sleep. Thus, we assessed if lower primary caregiver education level is associated with more sleep problems. We evaluated 4,636 children with autism spectrum disorder in the Autism Speaks Autism Treatment Network's United States and Canadian registry, whose caregivers completed the Children's Sleep Habits Questionnaire. Using regression analysis, there was an association between lower primary caregiver education level and more sleep problems. Secondary analyses demonstrated that younger age, Hispanic ethnicity, higher IQ, autism diagnosis and lower adaptive function were also associated with more sleep problems. The finding that lower primary caregiver education level was associated with increased sleep problems in a large sample of children with autism spectrum disorder highlights the importance of screening for risk factors affecting sleep to help moderate sleep problems.

Objective: A randomized pilot trial of gastrointestinal (GI) symptoms targeting probiotic for quality of life in autism spectrum disorder (ASD). Methods: Thirteen children, 3–12 years of age with ASD, anxiety, and GI symptoms, were randomized into a probiotic crossover trial of 8 weeks each on VISBIOME and placebo separated by a 3-week washout. VISBIOME contains eight probiotic species, mostly Lactobacillus and Bifidobacterium. Primary outcome was the Pediatric Quality of Life Inventory (PedsQL) GI module. Secondary outcomes included gut microbiota analysis, the Parent-Rated Anxiety Scale for ASD (PRAS-ASD), and parent-selected target symptoms. A mixed analysis model was applied. Results: Thirteen children were randomized, with 10 completing the study (77% retention): 6 in probiotic/placebo sequence, 4 in placebo/probiotic sequence. Adherence to study treatment was 96%. There were no serious adverse events (AEs), and more nonserious AEs occurred with placebo than with probiotic, including those attributable to treatment. Only 6 of the 10 guessed the correct treatment at the end of week 8. Over the 19-week trial, each outcome improved from baseline and PedsQL correlated significantly with abundance of Lactobacillus without discernable changes to microbiota composition/diversity. Although probiotic showed more improvement than placebo, PedsQL and PRAS-ASD were not statistically significant, as expected at this sample size. PedsQL effect size was d = 0.49 by the general model and d = 0.79 by simple comparison of week 8 changes. A parent-selected target symptom showed significant improvement in GI complaints on probiotic compared with placebo (p = 0.02, d = 0.79). Probiotic effects carried over through the 3-week washout. Conclusion: The VISBIOME formulation was safe and suggested a health benefit in children with ASD and GI symptoms who retained Lactobacillus. The moderate effect size compared with placebo warrants a larger trial using a parallel-group design.

Activation of free fatty acid receptor 1 (GPR40) by synthetic partial and full agonists occur via distinct allosteric sites. A crystal structure of GPR40-TAK-875 complex revealed the allosteric site for the partial agonist. Here we report the 2.76-Å crystal structure of human GPR40 in complex with a synthetic full agonist, compound 1, bound to the second allosteric site. Unlike TAK-875, which acts as a Gαq-coupled partial agonist, compound 1 is a dual Gαq and Gαs-coupled full agonist. compound 1 binds in the lipid-rich region of the receptor near intracellular loop 2 (ICL2), in which the stabilization of ICL2 by the ligand is likely the primary mechanism for the enhanced G protein activities. The endogenous free fatty acid (FFA), γ-linolenic acid, can be computationally modeled in this site. Both γ-linolenic acid and compound 1 exhibit positive cooperativity with TAK-875, suggesting that this site could also serve as a FFA binding site., GPR40 is a G-protein coupled receptor that binds to free fatty acids, mediating insulin and incretin secretion. Here, the authors present the crystal structure of human GPR40 with an agonist bound to an allosteric site located near the lipid-rich region that suggests a mechanism for biased agonism.

Multiple therapeutic opportunities have been suggested for compounds capable of selective activation of metabotropic glutamate 3 (mGlu

Background Adolescents and young adults (AYA) with HIV experience worse health outcomes than adults with HIV in the United States. Little is known about AYA patterns of utilization of costly healthcare resources. Methods We estimated utilization of outpatient, emergency department (ED), and inpatient care among 13–30 year-olds from 2006–2015. We stratified outpatient visits, ED visits and inpatient days per person-year (PY) by transmission mode (perinatal (PHIVY), non-perinatal (NPHIVY), age (13–17, 18–23, 24–30 years), CD4 strata (< 200, 200–499, ≥ 500 cells/µL) and presence or absence of viral load (VL) suppression ( Results Among 4,450 AYA (PHIVY: 15%; NPHIVY: 85%), mean (SD) follow-up was 2.8 years (2.5) [PHIVY: 4.2 years (3.1); NPHIVY: 2.5 years (2.3)]. Mean age was 21.4 years (PHIVY: 16.9 years; NPHIVY: 22.3 years) and female sex was 28% (PHIVY: 52%; NPHIVY: 23%). Among PHIVY, most person-time (PT) was spent between ages 13–23 years (13–17 years: 43%; 18–23 years: 45%), CD4 ≥ 500/µL (61%), and VL < 400 c/mL (69%). Among NPHIVY, most PT was spent between ages 24 and 30 years (56%), CD4 ≥ 500/µL (54%), and VL < 400 c/mL (66%). PT spent while prescribed ARVs and VL ≥ 400 c/mL was 30% (PHIVY) and 24% (NPHIVY). For both PHIVY and NPHIVY, outpatient visit rates were higher at younger ages (13–17 years and 18–23 years), lower CD4 (< 200, 200–499/µL), and among those prescribed ARVs (Figure 1). Rates of ED visits and inpatient days were higher during PT spent at older ages (18–23 years, 24–30 years), lower CD4 (< 200, 200–499/µL), and VL ≥ 400 c/mL (Figures 2 and 3). Overall, utilization was higher among PHIVY than NPHIVY (outpatient: 12.1 vs. 6.0/PY; ED: 0.4 vs. 0.3/PY; inpatient: 1.5 vs. 0.8/PY). The overall rate of AIDS-defining conditions was 4.5/100 PY (Figure 4). Conclusion Among AYA with HIV, more ED visits and inpatient days were observed during time spent at older ages, lower CD4 counts, and VL ≥ 400 c/mL. While AIDS-defining conditions were rare, associated resource utilization was substantial. Interventions to improve retention in care, virologic suppression, and immune response may improve outcomes, and thus decrease costly resource utilization, for AYA with HIV as they transition to adulthood. Disclosures All authors: No reported disclosures.

Identification of orthosteric mGlu(2/3) receptor agonists capable of discriminating between individual mGlu2 and mGlu3 subtypes has been highly challenging owing to the glutamate-site sequence homology between these proteins. Herein we detail the preparation and characterization of a series of molecules related to (1S,2S,5R,6S)-2-aminobicyclo[3.1.0]hexane-2,6-dicarboxylate 1 (LY354740) bearing C4-thiotriazole substituents. On the basis of second messenger responses in cells expressing other recombinant human mGlu2/3 subtypes, a number of high potency and efficacy mGlu2 receptor agonists exhibiting low potency mGlu3 partial agonist/antagonist activity were identified. From this, (1R,2S,4R,5R,6R)-2-amino-4-(1H-1,2,4-triazol-3-ylsulfanyl)bicyclo[3.1.0]hexane-2,6-dicarboxylic acid 14a (LY2812223) was further characterized. Cocrystallization of 14a with the amino terminal domains of hmGlu2 and hmGlu3 combined with site-directed mutation studies has clarified the underlying molecular basis of this unique pharmacology. Evaluation of 14a in a rat model responsive to mGlu2 receptor activation coupled with a measure of central drug disposition provides evidence that this molecule engages and activates central mGlu2 receptors in vivo.

As part of our ongoing research to identify novel agents acting at metabotropic glutamate 2 (mGlu2) and 3 (mGlu3) receptors, we have previously reported the identification of the C4α-methyl analog of mGlu2/3 receptor agonist 1 (LY354740). This molecule, 1S,2S,4R,5R,6S-2-amino-4-methylbicyclo[3.1.0]hexane-2,6-dicarboxylate 2 (LY541850), exhibited an unexpected mGlu2 agonist/mGlu3 antagonist pharmacological profile, whereas the C4β-methyl diastereomer (3) possessed dual mGlu2/3 receptor agonist activity. We have now further explored this structure–activity relationship through the preparation of cyclic and acyclic C4-disubstituted analogs of 1, leading to the identification of C4-spirocyclopropane 5 (LY2934747), a novel, potent, and systemically bioavailable mGlu2/3 receptor agonist which exhibits both antipsychotic and analgesic properties in vivo. In addition, through the combined use of protein–ligand X-ray crystallography employing recombinant human mGlu2/3 receptor amino terminal domains, molecular mod...

A challenge in the structure-based design of specificity is modeling the negative states, i.e., the complexes that you do not want to form. This is a difficult problem because mutations predicted to destabilize the negative state might be accommodated by small conformational rearrangements. To overcome this challenge, we employ an iterative strategy that cycles between sequence design and protein docking in order to build up an ensemble of alternative negative state conformations for use in specificity prediction. We have applied our technique to the design of heterodimeric CH3 interfaces in the Fc region of antibodies. Combining computationally and rationally designed mutations produced unique designs with heterodimer purities greater than 90%. Asymmetric Fc crystallization was able to resolve the interface mutations; the heterodimer structures confirmed that the interfaces formed as designed. With these CH3 mutations, and those made at the heavy-/light-chain interface, we demonstrate one-step synthesis of four fully IgG-bispecific antibodies.

Gram-negative bacteria typically overcome poor permeability of outer membranes through general porins like OmpF and OmpC, which form water-filled transmembrane pores permitting diffusion of hydrophilic molecules with no particular selectivity. Many bacteria lacking such general porins use substrate-specific porins to overcome growth-limiting conditions and facilitate selective transport of metabolites. Exclusive reliance on substrate-specific porins yields lower membrane permeability to small molecules (

Upon removal of the regulatory insert (RI), the first nucleotide binding domain (NBD1) of human cystic fibrosis transmembrane conductance regulator (CFTR) can be heterologously expressed and purified in a form that remains stable without solubilizing mutations, stabilizing agents or the regulatory extension (RE). This protein, NBD1 387-646(Delta405-436), crystallizes as a homodimer with a head-to-tail association equivalent to the active conformation observed for NBDs from symmetric ATP transporters. The 1.7-A resolution X-ray structure shows how ATP occupies the signature LSGGQ half-site in CFTR NBD1. The DeltaF508 version of this protein also crystallizes as a homodimer and differs from the wild-type structure only in the vicinity of the disease-causing F508 deletion. A slightly longer construct crystallizes as a monomer. Comparisons of the homodimer structure with this and previously published monomeric structures show that the main effect of ATP binding at the signature site is to order the residues immediately preceding the signature sequence, residues 542-547, in a conformation compatible with nucleotide binding. These residues likely interact with a transmembrane domain intracellular loop in the full-length CFTR channel. The experiments described here show that removing the RI from NBD1 converts it into a well-behaved protein amenable to biophysical studies yielding deeper insights into CFTR function.

Identification of orthosteric mGlu(2/3) receptor agonists capable of discriminating between individual mGlu2 and mGlu3 subtypes has been highly challenging owing to the glutamate-site sequence homology between these proteins. Herein we detail the preparation and characterization of a series of molecules related to (1S,2S,5R,6S)-2-aminobicyclo[3.1.0]hexane-2,6-dicarboxylate 1 (LY354740) bearing C4-thiotriazole substituents. On the basis of second messenger responses in cells expressing other recombinant human mGlu2/3 subtypes, a number of high potency and efficacy mGlu2 receptor agonists exhibiting low potency mGlu3 partial agonist/antagonist activity were identified. From this, (1R,2S,4R,5R,6R)-2-amino-4-(1H-1,2,4-triazol-3-ylsulfanyl)bicyclo[3.1.0]hexane-2,6-dicarboxylic acid 14a (LY2812223) was further characterized. Cocrystallization of 14a with the amino terminal domains of hmGlu2 and hmGlu3 combined with site-directed mutation studies has clarified the underlying molecular basis of this unique pharmacology. Evaluation of 14a in a rat model responsive to mGlu2 receptor activation coupled with a measure of central drug disposition provides evidence that this molecule engages and activates central mGlu2 receptors in vivo.

As part of our ongoing research to identify novel agents acting at metabotropic glutamate 2 (mGlu2) and 3 (mGlu3) receptors, we have previously reported the identification of the C4α-methyl analog of mGlu2/3 receptor agonist 1 (LY354740). This molecule, 1S,2S,4R,5R,6S-2-amino-4-methylbicyclo[3.1.0]hexane-2,6-dicarboxylate 2 (LY541850), exhibited an unexpected mGlu2 agonist/mGlu3 antagonist pharmacological profile, whereas the C4β-methyl diastereomer (3) possessed dual mGlu2/3 receptor agonist activity. We have now further explored this structure-activity relationship through the preparation of cyclic and acyclic C4-disubstituted analogs of 1, leading to the identification of C4-spirocyclopropane 5 (LY2934747), a novel, potent, and systemically bioavailable mGlu2/3 receptor agonist which exhibits both antipsychotic and analgesic properties in vivo. In addition, through the combined use of protein-ligand X-ray crystallography employing recombinant human mGlu2/3 receptor amino terminal domains, molecular modeling, and site-directed mutagenesis, a molecular basis for the observed pharmacological profile of compound 2 is proposed.

The X-ray structure of a putative BenF-like (gene name: PFL1329) protein from Pseudomonas fluorescens Pf-5 (PflBenF) has been determined at 2.6Å resolution. X-ray crystallography revealed a canonical 18-stranded β-barrel fold that forms a central pore with a diameter of ∼4.6Å, which is consistent with the size and physicochemical properties of the presumed aromatic acid substrate, benzoate. Detailed comparisons with the previously-determined structure of Pseudomonas aeruginosa OpdK, a vanillate influx channel, revealed an arginine-rich aromatic acid selectivity filter of nearly identical structure composed of seven highly conserved residues Arg∼Asp∼Arg∼Arg∼Ser∼Asp∼Arg (R∼D∼R∼R∼S∼D∼R sequence motif, where ∼ denotes intervening residues) that define the narrowest part of the pore.

As clinicians we would all agree that the goal for our patients is to induce remission, which is usually defined as symptom resolution. Restoring continence and absence of rectal bleeding would be signs that the mucosa is at most minimally inflamed if not healed. However, there have not been any data to confirm that symptomatic improvement alters the natural history of the disease, nor decreases the lifetime risk for surgery. Because we understand the potential complications of this disease, it should not be enough that we “settle” for symptom resolution, but aim instead to decrease the risk of complications and alter the natural history of the disease. Until recently, mucosal healing endpoints have not been included in clinical trials. Clinical endpoints lead to high placebo responses, potentially diluting the effect of the therapy, even in large multinational trials. The hard endpoint of endoscopic mucosal healing reduces the number needed to power a study for treatment effect. The relevant questions during this discussion are: 1) What is endoscopic healing? 2) How often can we achieve this in ulcerative colitis (UC)? 3) Does mucosal healing change disease outcomes? and 4) Does mucosal healing lower the rate of complications? The history of mucosal healing starts in 2001 when Bitton et al1 reported on clinical, biological, and histologic parameters that would predict time to clinical relapse. One of the only factors that was statistically significant was basal plasmacytosis on rectal biopsy. The hazard ratio (HR) for predicting clinical relapse was 4.5 and the authors concluded that this factor may help identify patients with inactive UC who will require optimal maintenance therapy. An accepted definition of endoscopic healing has yet to be developed and validated. Everyone would agree that return to normal vascular pattern, the absence of friability, or ulcerations fits the bill, but what about some mild erythema or granularity? If there is no friability (however you want to measure it), should that suffice? Mucosal healing was defined as either completely normal (score of 0) or mild (score of 1) in the ASCEND and ACT trials but 1 in the MMX (mesalamine) trials. Using the ASCEND criteria, mucosal healing was achieved in up to 80% of those patients on 4.8 g/mesalamine/day at week 6.2,3 Using the stricter subscore of 0, then this percentage fell to 30%. In the MMX trials, 77.6% of patients had a score of 1 on 4.8 g/day at the end of the trial at 12 weeks.4,5 In the infliximab trial, healing was achieved by 62% of the 5 mg/kg dose at week 8, and was sustained in 45.5% of patients at week 54.6 If a score of 0 or 1 is acceptable, then certainly mucosal healing as an endpoint is an achievable and reasonable goal. Just because the majority of patients may achieve mucosal healing, does it make any difference? In the ACT trial, those patients with documented mucosal healing at week 8 and 30 were more likely to be in remission than those who did not (P 0.009).6 We do not have such data from the mesalamine trials, as endoscopy at the end of the trial was not part of the protocol. It would, however, make intuitive sense that those patients without any symptoms at the end of the trial would most likely have scores of 1 or 0. In a currently ongoing prospective study, preliminary results from patients with active UC were presented.7 Patients with mild to moderate UC were treated with 6 weeks of 4 g/day oral and 2 g enemas. In 78 patients, 59 achieved clinical remission. Endoscopic activity was still present in only 5. After a mean follow-up of 8.7 months, 15 (26%) relapsed. The cumulative rate of relapse at 1 year was 23% in patients with clinical and endoscopic remission and 80% in patients with only clinical remission. The conclusion of the authors was that persistence of endoscopic activity is a rare event, with active UC achieving clinical remission after 6 weeks, but a very strong predictor of early relapse. Data from the IBSEN study in Norway followed incident cases of UC over a period of 5 years.8 In all, 354 patients were endoscoped at 6 months to 2 years after their diagnosis, 328 Received for publication September 25, 2008; Accepted December 15, 2008. From the *Mayo Clinic, Rochester, Minnesota, Mount Sinai Hospital, New York, New York, University of Michigan Hospital, Ann Arbor, Michigan. Reprints: Dr. Peter Higgins, Box 0682, 1150 West Medical Center Dr., Ann Arbor, MI 48109 (e-mail: phiggins@umich.edu). Copyright © 2009 Crohn’s & Colitis Foundation of America, Inc. DOI 10.1002/ibd.20875 Published online 11 February 2009 in Wiley InterScience (www. interscience.wiley.com).