Repurposed floxacins targeting RSK4 prevent chemoresistance and metastasis in lung and bladder cancer

Lung and bladder cancers are mostly incurable because of the early development of drug resistance and metastatic dissemination. Hence, improved therapies that tackle these two processes are urgently needed to improve clinical outcome. We have identified RSK4 as a promoter of drug resistance and metastasis in lung and bladder cancer cells. Silencing this kinase, through either RNA interference or CRISPR, sensitized tumor cells to chemotherapy and hindered metastasis in vitro and in vivo in a tail vein injection model. Drug screening revealed several floxacin antibiotics as potent RSK4 activation inhibitors, and trovafloxacin reproduced all effects of RSK4 silencing in vitro and in/ex vivo using lung cancer xenograft and genetically engineered mouse models and bladder tumor explants. Through x-ray structure determination and Markov transient and Deuterium exchange analyses, we identified the allosteric binding site and revealed how this compound blocks RSK4 kinase activation through binding to an allosteric site and mimicking a kinase autoinhibitory mechanism involving the RSK4's hydrophobic motif. Last, we show that patients undergoing chemotherapy and adhering to prophylactic levofloxacin in the large placebo-controlled randomized phase 3 SIGNIFICANT trial had significantly increased (P = 0.048) long-term overall survival times. Hence, we suggest that RSK4 inhibition may represent an effective therapeutic strategy for treating lung and bladder cancer.

IKKε and TBK1 in diffuse large B-cell lymphoma: A possible mechanism of action of an IKKε/TBK1 inhibitor to repress NF-κB and IL-10 signalling

The IKK‐related kinases, IKKε and TBK1, have essential roles in innate immunity in part through modifying MYD88 signalling from the Toll‐like receptors to regulate NF‐κB signalling. We investigated the expression and function of IKKε and TBK1, in diffuse large B‐cell lymphoma (DLBCL). DLBCL cell lines and patient‐derived xenografts were used to determine their sensitivity to IKKε and TBK1 inhibitors. To understand the function of IKKε and TBK1 secreted factors were determined following administration of inhibitors. Gene expression microarrays were used to determine the transcriptional effects of inhibitors. Higher TBK1 mRNA levels associated with poorer clinical outcome but IKKε and TBK1 were expressed in both germinal centre and non‐germinal centre types of DLBCL. Survival of cell lines Ly10, Ly03 and Pfeiffer, and of some primary human lymphoma cells, was suppressed by a small molecule IKKε/TBK1 inhibitor, DMX3433. DMX3433 reduced IL‐10 production from Ly10 and repressed NF‐κB mediated transcription. Inhibition of IKKε and TBK1 warrants further investigation as a potential therapeutic route to suppress NF‐κB signalling in lymphoma.

Releasing the technical 'shackles' on GPCR drug discovery: opportunities enabled by detergent-free polymer lipid particle (PoLiPa) purification

G-protein-coupled receptor (GPCR) drug research is presently hindered by the technical challenges associated with generating purified receptors. Consequently, the application of critical modern discovery technologies has been limited, and the vast untapped opportunity for new GPCR-directed medicines is not being realised. A simple but transformative solution is to purify receptors without removing them from their native phospholipid environment by using polymer lipid particle (PoLiPa) technology, with reagents such as styrene-maleic acid co-polymer (SMA). Compared with contemporary detergent-based and stabilising mutagenesis methods, the PoLiPa approach is simple and generic and, therefore, offers huge advantages, with the potential to revolutionise GPCR research by facilitating the availability of the purified receptors that are required for structural biology, biophysical, and panning technologies.

Multipoint genome-wide linkage scan for nonword repetition in a multigenerational family further supports chromosome 13q as a locus for verbal trait disorders

Verbal trait disorders encompass a wide range of conditions and are marked by deficits in five domains that impair a person's ability to communicate: speech, language, reading, spelling, and writing. Nonword repetition is a robust endophenotype for verbal trait disorders that is sensitive to cognitive processes critical to verbal development, including auditory processing, phonological working memory, and motor planning and programming. In the present study, we present a six-generation extended pedigree with a history of verbal trait disorders. Using genome-wide multipoint variance component linkage analysis of nonword repetition, we identified a region spanning chromosome 13q14-q21 with LOD = 4.45 between 52 and 55 cM, spanning approximately 5.5 Mb on chromosome 13. This region overlaps with SLI3, a locus implicated in reading disability in families with a history of specific language impairment. Our study of a large multigenerational family with verbal trait disorders further implicates the SLI3 region in verbal trait disorders. Future studies will further refine the specific causal genetic factors in this locus on chromosome 13q that contribute to language traits.

The discovery of a highly selective 5,6,7,8-tetrahydrobenzo[4,5]thieno[2,3-d]pyrimidin-4(3H)-one SIRT2 inhibitor that is neuroprotective in an in vitro Parkinson's disease model

Sirtuins, NAD(+) -dependent histone deacetylases (HDACs), have recently emerged as potential therapeutic targets for the treatment of a variety of diseases. The discovery of potent and isoform-selective inhibitors of this enzyme family should provide chemical tools to help determine the roles of these targets and validate their therapeutic value. Herein, we report the discovery of a novel class of highly selective SIRT2 inhibitors, identified by pharmacophore screening. We report the identification and validation of 3-((2-methoxynaphthalen-1-yl)methyl)-7-((pyridin-3-ylmethyl)amino)-5,6,7,8-tetrahydrobenzo[4,5]thieno[2,3-d]pyrimidin-4(3H)-one (ICL-SIRT078), a substrate-competitive SIRT2 inhibitor with a Ki value of 0.62 ± 0.15 μM and more than 50-fold selectivity against SIRT1, 3 and 5. Treatment of MCF-7 breast cancer cells with ICL-SIRT078 results in hyperacetylation of α-tubulin, an established SIRT2 biomarker, at doses comparable with the biochemical IC50 data, while suppressing MCF-7 proliferation at higher concentrations. In concordance with the recent reports that suggest SIRT2 inhibition is a potential strategy for the treatment of Parkinson's disease, we find that compound ICL-SIRT078 has a significant neuroprotective effect in a lactacystin-induced model of Parkinsonian neuronal cell death in the N27 cell line. These results encourage further investigation into the effects of ICL-SIRT078, or an optimised derivative thereof, as a candidate neuroprotective agent in in vivo models of Parkinson's disease.

The melanocortin 4 receptor: oligomer formation, interaction sites and functional significance

This study involves the structural and functional properties of the recombinant melanocortin 4 receptor (MC(4)R) expressed in the HEK-293 cell line. Using co-immuno-purification approaches, the receptor appears to be an oligomer, which can be crosslinked through disulphide bonds involving a native cysteine residue (84) to give a dimeric species. This position is located near the cytosolic region of transmembrane segment 2 and it is suggested that this is an interacting interface between MC(4)R monomers. Using co-expression of the native protein and a C84A mutant, it appears that the receptor also forms higher order oligomers via alternative interfaces. Interestingly, disulphide crosslink formation does not occur if the receptor is uncoupled from its G-protein, even though the oligomeric state is preserved. This suggests that the conformational changes, which occur on activation, affect the TM2 interface. The pharmacology of the agonist, NDP-MSH, indicates that the MC(4)R retains high affinity for the ligand in the absence of the G-protein but occupancy for the ligand is increased. The data can be interpreted to suggest that the G-protein exerts a negative allosteric effect on the receptor. Co-expression of one receptor lacking the ability to signal with another, which cannot bind the agonist, restored ligand-dependent activation of the G-protein to situations in which neither receptor on its own could activate the G-protein. Such transactivation suggests meaningful cross talk between the receptor subunits in the oligomeric complex. These studies demonstrate further unique features of the MC(4)R.

The design of chronic toxicology studies of monoclonal antibodies: implications for the reduction in use of non-human primates

The changing environment of monoclonal antibody (mAb) development is impacting on the cost of drug development and the use of experimental animals, particularly non-human primates (NHPs). The drive to reduce these costs is huge and involves rethinking and improving nonclinical studies to make them more efficient and more predictive of man. While NHP use might be unavoidable in many cases because of the exquisite specificity and consequent species selectivity of mAbs, our increasing knowledge base can be used to improve drug development and maximise the output of experimental data. Data on GLP regulatory toxicology studies for 58mAbs were obtained from 10 companies across a wide range of therapeutic indications. These data have been used to investigate current practice and identify study designs that minimise NHP use. Our analysis shows that there is variation in the number of animals used for similar studies. This information has been used to develop practical guidance and make recommendations on the use of science-based rationale to design studies using fewer animals taking into account the current regulatory guidance. There are eight recommendations intended to highlight areas for consideration. They include guidance on the main group size, the inclusion of recovery groups and the number of dose groups used in short and long term chronic toxicology studies.

Hospice use in Alabama, 2002-2005

CONTEXT

The literature predominately describes hospice utilization among Medicare recipients, with a limited number of reports describing use among all age groups.

OBJECTIVES

This study aimed to describe and compare patterns of hospice use among decedents of all ages in Alabama using a population-based approach.

METHODS

We obtained death certificates for Alabama residents who died from January 1, 2002 to December 31, 2005 (n=178,420). To ascertain hospice use, we linked death certificates to the hospice administering care using state-mandated listings of deaths reported by hospices. Additionally, each decedent's residence at death was geocoded and area-level socioeconomic status (SES) measures were added.

RESULTS

From 2002 to 2005, a total of 43,638 Alabamians died while under hospice care, representing a quarter (24.5%) of all deaths in the state. During this four-year span, the rate of hospice use increased by nearly 15% (22.2%-25.6%). As expected, rates of hospice use increased with age at death. For the SES indicators for poverty, education, and income, rates of hospice use increased as SES improved. However, this pattern was found to vary by race and metro/nonmetro status.

CONCLUSIONS

In addition to revealing racial, geographic, and other disparities in hospice care across Alabama, our results indicate usage rates in Alabama trail behind those observed nationally. We also identified previously unreported interactions between race, urbanization level, and poverty classification. Future studies should explore whether such relationships exist elsewhere and the rationale for their occurrence.

Barriers to hospice care in Alabama: provider-based perceptions

Few studies have evaluated barriers to hospice from a hospice provider perspective. We assessed such views via a postal survey to all licensed hospices in Alabama (N = 193)-response = 55.4%. Most providers considered physicians and health care professionals to be somewhat knowledgeable of hospice, but also indicated a lack of knowledge constituted the barrier with the most impact in their communities. Respondents also cited physician difficulties with discussing end of life with patients and prognosticating death within 6 months as leading barriers. Providers also described Medicare reimbursement cap issues that have resulted in barriers to hospice. Our findings were similar to previous investigations assessing provider perceptions. Future studies should explore how reimbursement cap issues affect the receipt and delivery of hospice care.

The future of non-human primate use in mAb development

It has been predicted that the use of non-human primates (NHPs) is going to increase considerably in the development of monoclonal antibodies (mAbs). Opportunities exist to focus on a rigorous, science-based approach to drug development, however, which will minimize this increase. In this article, the authors review current and future NHP use in mAb development based on surveys, experience and expert opinion and propose a framework that will minimize future NHP use and continue to support science and innovation.

Hospice use among cancer decedents in Alabama, 2002-2005

INTRODUCTION

Most studies that describe hospice use among cancer patients use the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, which has known limitations. We used vital records data to describe patterns of hospice use among cancer decedents in Alabama.

METHODS

To ascertain hospice use, we linked death certificates from 2002 through 2005 for people who died from cancer to listings of deaths reported by hospices. To evaluate accessibility of care, we calculated straight-line distances between decedent residence at death and the hospice providing care. We used these distances to estimate the reach of each hospice and identify the number of hospice nonusers residing in these areas.

RESULTS

During the study period, 52.0% of cancer decedents in Alabama received hospice care from 165 hospices. Nearly two-thirds of Alabama counties contain at least 1 hospice. Whites (53.6%) used hospice at a significantly higher rate than blacks (47.0%), but the rate of use was similar for women (53.2%) and men (51.0%). For people who were eligible for Medicare, 53.0% received hospice care. The median distance between decedent's residence and the hospice providing care was 9.8 miles. This distance was slightly shorter for blacks than whites and roughly equal by sex.

CONCLUSION

Alabamians use hospice at lower rates than observed elsewhere. Barriers to hospice care in Alabama must be identified and addressed.

Review: clinical variability and genetic heterogeneity in multiple epiphyseal dysplasia

This review reports on multiple epiphyseal dysplasia (MED), first described clinically in the early part of the 20th century. Over 50 years later, we are now beginning to unravel the mystery behind the genetic mutations involved in triggering the changes in cartilage observed in this condition. In the past decade considerable progress has been made in identifying the underlying genetic defect in some forms of MED. Understanding the precise effect that these molecular changes have on the integrity of the cartilage extracellular matrix will lead the way in identifying the complex disease pathophysiology that defines MED. In addition, a greater understanding of the role and interactions of specific cartilage molecules may reveal the basis of more widespread cartilage disorders such as osteoarthritis.

Pseudoachondroplasia and multiple epiphyseal dysplasia: mutation review, molecular interactions, and genotype to phenotype correlations

Pseudoachondroplasia (PSACH) and multiple epiphyseal dysplasia (MED) constitute a bone dysplasia family, which is both genetically and phenotypically heterogeneous. The disease spectrum ranges from mild MED, which manifests with pain and stiffness in the joints and delayed and irregular ossification of the epiphyses, to the more severe PSACH, which is characterized by marked short stature, deformity of the legs, and ligamentous laxity. PSACH is almost exclusively caused by mutations in cartilage oligomeric matrix protein (COMP) whereas various forms of MED are caused by mutations in the genes encoding COMP, type IX collagen (COL9A1, COL9A2, and COL9A3), matrilin-3 (MATN3), and solute carrier member 26, member 2 gene (SLC26A2). In this review we discuss specific disease-causing mutations and the clustering of these mutations in functionally and structurally important regions of the respective gene products, genotype to phenotype correlations, and the diagnostic relevance of mutation screening in these osteochondrodysplasias.

Vocal development of 9-month-old babies with cleft palate

This study compared the prelinguistic vocal development of 9-month-old babies with unrepaired cleft palate (n = 30) and age-matched peers (n = 15). Samples of the babies' spontaneous vocalizations were obtained while they interacted with their primary caregiver during play. The groups were compared on a number of variables including (a) canonical babbling ratios, (b) percentage of babies who reached the canonical babbling stage by 9 months, (c) syllable and segmental aspects of babbling, and (d) vocal frequency. Results indicated that the babies with cleft palate had smaller canonical babbling ratios than their age-matched peers, with just 57% of the babies with cleft palate reaching the canonical babbling stage by 9 months compared to 93% of the noncleft babies. Although syllable types and length were similar for the two groups, differences were noted for consonant characteristics. The babies with cleft palate had smaller consonant inventories, with fewer stops, glides, and velars noted. Glottals occurred more frequently in the vocalizations of the babies with cleft palate. Finally, no statistically significant difference was noted in the number of vocalizations produced by the two groups. Some possible explanations for why babies with cleft palate are delayed in babbling are explored.

Mutations in the region encoding the von Willebrand factor A domain of matrilin-3 are associated with multiple epiphyseal dysplasia

Multiple epiphyseal dysplasia (MED) is a relatively mild and clinically variable osteochondrodysplasia, primarily characterized by delayed and irregular ossification of the epiphyses and early-onset osteoarthritis. Mutations in the genes encoding cartilage oligomeric matrix protein (COMP) and type IX collagen (COL9A2 and COL9A3) have previously been shown to cause different forms of MED (refs. 4-13). These dominant forms of MED (EDM1-3) are caused by mutations in the genes encoding structural proteins of the cartilage extracellular matrix (ECM); these proteins interact with high affinity in vitro. A recessive form of MED (EDM4) has also been reported; it is caused by a mutation in the diastrophic dysplasia sulfate transporter gene (SLC26A). A genomewide screen of family with autosomal-dominant MED not linked to the EDM1-3 genes provides significant genetic evidence for a MED locus on the short arm of chromosome 2 (2p24-p23), and a search for candidate genes identified MATN3 (ref. 18), encoding matrilin-3, within the critical region. Matrilin-3 is an oligomeric protein that is present in the cartilage ECM. We have identified two different missense mutations in the exon encoding the von Willebrand factor A (vWFA) domain of matrilin-3 in two unrelated families with MED (EDM5). These are the first mutations to be identified in any of the genes encoding the matrilin family of proteins and confirm a role for matrilin-3 in the development and homeostasis of cartilage and bone.

Surgical correction of blepharoptosis in patients with myasthenia gravis

PURPOSE

To describe the results of surgical correction of blepharoptosis in a series of patients with myasthenia gravis (MG).

METHODS

In this retrospective case series, we reviewed the medical records of all patients with MG who did not respond to medical therapy and underwent surgical correction for blepharoptosis at the Mayo Clinic between 1985 and 1999. The primary outcome measure was change in interpalpebral eyelid fissure height.

RESULTS

Sixteen blepharoptosis procedures were performed on 10 patients with MG. Eight of the 10 patients had ocular MG. Two of the 10 patients had systemic MG. Of the 16 procedures performed, 9 were external levator advancements (ELA), six were frontalis slings, and one was a tarsomyectomy. Patients were followed postoperatively for an average of 34 months (range, 14-126 months). The amount of ptosis was quantified pre- and postoperatively for seven of the nine eyelids that underwent ELA. For these seven eyelids (five patients), there was a statistically significant improvement in the mean interpalpebral eyelid fissure height from 3.7 mm preoperatively to 7.8 mm postoperatively, with a mean difference of 4.1 mm (95% confidence interval 1.9 mm to 6.25 mm, p = 0.0038). Postoperative complications included worsened diplopia in one patient with ELA and exposure keratopathy in one patient with frontalis sling. Two of the ELA eyelids developed recurrent ptosis requiring additional surgery more than 2 years after the initial procedure.

CONCLUSIONS

Blepharoptosis surgery can achieve eyelid elevation in patients who have failed to respond to medical therapy for MG. Potential complications include worsened diplopia and exposure keratopathy.

Cartilage oligomeric matrix protein interacts with type IX collagen, and disruptions to these interactions identify a pathogenetic mechanism in a bone dysplasia family

Cartilage oligomeric matrix protein (COMP) and type IX collagen are key structural components of the cartilage extracellular matrix and have important roles in tissue development and homeostasis. Mutations in the genes encoding these glycoproteins result in two related human bone dysplasias, pseudoachondroplasia and multiple epiphyseal dysplasia, which together comprise a "bone dysplasia family." It has been proposed that these diseases have a similar pathophysiology, which is highlighted by the fact that mutations in either the COMP or the type IX collagen genes produce multiple epiphyseal dysplasia, suggesting that their gene products interact. To investigate the interactions between COMP and type IX collagen, we have used rotary shadowing electron microscopy and real time biomolecular (BIAcore) analysis. Analysis of COMP-type IX collagen complexes demonstrated that COMP interacts with type IX collagen through the noncollagenous domains of type IX collagen and the C-terminal domain of COMP. Furthermore, peptide mapping identified a putative collagen-binding site that is associated with known human mutations. These data provide evidence that disruptions to COMP-type IX collagen interactions define a pathogenetic mechanism in a bone dysplasia family.

Reliability of listener transcriptions of compensatory articulations

OBJECTIVE

This study examined the ability of speech-language pathologists to transcribe compensatory articulation errors.

DESIGN

Speech-language pathologists phonetically transcribed audiorecordings of 130 monosyllabic words, 70 of which contained compensatory articulations.

PARTICIPANTS

The participants for this study were two groups of 10 speech-language pathologists. Group I included speech-language pathologists who were experienced in evaluating children with cleft palate, and group II speech-language pathologists were not.

RESULTS

Marked variability was evident across listeners, with percentages of agreement ranging from 19 to 71 (mean agreement = 41%). The experienced listeners performed significantly better on the transcription task than the inexperienced listeners, but poor interjudge agreement was evident across both groups.

CONCLUSIONS

The results of this study suggest that speech-language pathologists may differ in their understanding of the auditory perceptual characteristics of compensatory articulations. The results underscore the need for increased training and standardization of transcription procedures.

Surgical correction of blepharoptosis in patients with myasthenia gravis

PURPOSE

To describe the results of surgical correction of blepharoptosis in a series of patients with myasthenia gravis.

METHODS

We reviewed the medical records of all patients with myasthenia gravis who underwent surgical correction for blepharoptosis at the Mayo Clinic between 1985 and 1999. The primary outcome measure was change in interpalpebral eyelid fissure height.

RESULTS

Eighteen blepharoptosis procedures were performed on 11 patients with myasthenia gravis. Eight of the 11 patients had ocular myasthenia gravis, and 3 had systemic myasthenia gravis. Of the 18 procedures performed, 11 were external levator advancements (ELA), 6 were frontalis slings, and 1 was a tarsomyectomy. Patients were followed up postoperatively for an average of 34 months (range, 9 to 126 months). The amount of ptosis was quantified preoperatively and postoperatively for 9 of the 11 eyelids that underwent ELA. For these eyelids, there was a statistically significant improvement in the mean interpalpebral eyelid fissure height, from 4.2 mm preoperatively to 8.1 mm postoperatively, with a mean difference of 3.9 mm (95% confidence interval, 2.3 to 5.5 mm; P = .0005). Postoperative complications included worsened diplopia in 1 patient who underwent ELA and exposure keratopathy in 1 patient who underwent a frontalis sling procedure. Two of the eyelids that underwent ELA developed recurrent ptosis, requiring additional surgery more than 2 years after the initial procedure.

CONCLUSION

Surgical correction of blepharoptosis is an appropriate treatment option in patients with myasthenia gravis who fail medical therapy. Potential complications include worsened diplopia and exposure keratopathy.

Lacrimal bypass surgery in patients with sarcoidosis

PURPOSE

To examine the results of lacrimal bypass surgery in patients with sarcoidosis.

METHODS

Patients with sarcoidosis who underwent dacryocystorhinostomy (DCR) or conjunctivodacryocystorhinostomy (CDCR) in two practice settings from 1986 through 1995 were identified and their medical records reviewed.

RESULTS

Twelve patients, of whom eight were women, underwent bilateral DCR or CDCR to treat nasolacrimal duct obstruction associated with sarcoidosis. The initial diagnosis of sarcoidosis was established in four patients from a biopsy specimen obtained during DCR. The ages of the patients at diagnosis of sarcoidosis ranged from 39 to 64 years (mean, 49.6 years; median, 45.5 years), whereas their ages at the time of surgery ranged from 42 to 72 years (mean and median, 55 years). The average duration of postoperative follow-up evaluation was 44 months (median, 38.5 months; range, 10 to 82 months). All patients received local corticosteroids postoperatively, and nine patients (75%) were treated with prednisone. Of the 24 lacrimal procedures, 23 (95.8%) were patent to irrigation at the last follow-up examination, and all patients were asymptomatic.

CONCLUSION

Lacrimal drainage obstruction may be the initial manifestation of sarcoidosis, and tissue obtained during DCR may help to establish the diagnosis. A successful surgical outcome may require intensive and occasionally long-term therapy with local and systemic corticosteroids.

Follow-up of patients with essential blepharospasm who underwent eyelid protractor myectomy at the Mayo Clinic from 1980 through 1995

PURPOSE

To determine the efficacy of eyelid protractor myectomy (subtotal excision of the orbicularis oculi, the corrugator supercilii, and the procerus muscles) for the treatment of essential blepharospasm, and to evaluate the need for and the effectiveness of botulinum toxin (BT) injections in these patients.

METHODS

The medical records of all patients who underwent eyelid protractor myectomy at the Mayo Clinic (Rochester, MN) from 1980 through 1995 were reviewed. The Health Status Questionnaire was used to assess overall medical and mental health, and a questionnaire specific to eyelid spasms was developed.

RESULTS

Fifty-four white patients, of whom 32 (59%) were women, underwent myectomy. The average age at diagnosis of essential blepharospasm was 64 years (median, 65 years; range, 43 to 84 years), whereas the average age at the time of myectomy was 66 years (median, 66 years; range, 51 to 85 years). Of the 14 patients who were treated with BT injections before myectomy, the average interval between the initial injection and surgery was 21 months (median, 20 months; range, 2 to 51 months). Patients who had been treated with BT injections before myectomy were more likely to receive injections postoperatively than were those patients who had not been treated with BT (p < 0.001). Twenty patients were treated with BT injections after myectomy; the overall probability of receiving BT five years after surgery was 46%. Time from myectomy to treatment with BT varied considerably; mean, 880 days; median, 659 days; range, 3 to 4221 days. Postoperative follow-up for those patients who did not receive BT after myectomy ranged from 2 to 5935 days (mean, 2354 days; median, 1722 days). Although the probability of receiving BT injections after myectomy was not associated with age or sex, there was a significant association with the time interval during which the myectomy had been performed (related to the availability of BT as an adjunctive therapy). Of the 41 patients who were alive when the study was conducted, 32 (78%) completed a follow-up survey. Thirty of those (94%) said myectomy provided short-term and long-term benefits. Of the 11 patients who received BT injections before and after myectomy, six (55%) said the toxin was more effective in ameliorating eyelid spasms after surgery and four (36%) required injections less frequently after myectomy. Results from the Health Status Questionnaire showed no significant differences between patients who underwent myectomy and control subjects.

CONCLUSIONS

Eyelid protractor myectomy provides subjective benefit to patients with essential blepharospasm and decreases the long-term need for BT injections in approximately 50% of these patients. Although the probability of receiving postoperative BT paralleled its availability, patients who received both preoperative and postoperative BT perceived either increased efficacy of the toxin injections, longer-lasting effects, or both, after myectomy. Patients with severe disability from blepharospasm benefited more from myectomy than did patients with relatively mild symptoms.

Conversational skills of preschool and school-age children with cleft lip and palate

OBJECTIVE

The purpose of this study was to examine the conversational skills of preschool and school-age children with cleft lip and palate.

DESIGN

The children were audio- and videotaped during interactions with an unfamiliar adult. In addition, standardized measures of speech and language were administered, and ratings of resonance were obtained. Comparisons were made between the children with cleft lip and palate and their same-age peers on measures of conversational participation and a standardized test of pragmatic skills.

PARTICIPANTS

Participants were 20 children with unilateral cleft lip and palate (10 preschoolers and 10 school-age children) recruited from the Craniofacial Team at Rainbow Babies and Children's Hospital, Cleveland (OH) and 20 noncleft peers matched for gender, age, and socioeconomic status.

MAIN OUTCOME MEASURES

Separate comparisons were made for the preschool children with cleft lip and palate and their noncleft peers, and the school-age children with cleft lip and palate and their noncleft peers on eight measures of conversational assertiveness/responsiveness and the standardized tests of pragmatics. Next, each child with cleft lip and palate was classified for level of conversational participation.

RESULTS

Paired t tests revealed no significant differences between the preschool and school-age children with cleft lip and palate and their noncleft peers in level of conversational participation. However, individual child comparisons revealed less assertive profiles of conversational participation for 50% of the preschool and 20% of the school-age children with cleft lip and palate.

CONCLUSIONS

Children with cleft lip and palate may show a less assertive style of conversational participation, at least during the preschool years. Therefore, craniofacial team evaluations should include examination of conversational competency, particularly for children who are demonstrating difficulty with other aspects of speech, language, or social development.

Substituted pyrazoles as novel selective ligands for the human dopamine D4 receptor

Two novel series of 3-(heterocyclylmethyl)pyrazoles have been synthesised and evaluated as ligands for the human dopamine D4 receptor. Compounds in series I (exemplified by 8k) have a phenyl ring joined to the 4-position of the pyrazole while those in series II (exemplified by 15j) have a 5-phenyl ring linked by a saturated chain to the 4-position of the pyrazole. Both series supplied compounds with excellent affinity for the human D4 and good selectivity over other dopamine receptors. Excellent selectivity over calcium, sodium, and potassium ion channels was also achieved.

Biological profile of L-745,870, a selective antagonist with high affinity for the dopamine D4 receptor

L-745,870,(3-([4-(4-chlorophenyl)piperazin-1-yl]methyl)-1H- pyrollo[2,3-b] pyridine, was identified as a selective dopamine D4 receptor antagonist with excellent oral bioavailability and brain penetration. L-745,870 displaced specific binding of 0.2 nM [3H] spiperone to cloned human dopamine D4 receptors with a binding affinity (Ki) of 0. 43 nM which was 5- and 20-fold higher than that of the standard antipsychotics haloperidol and clozapine, respectively. L-745,870 exhibited high selectivity for the dopamine D4 receptor (>2000 fold) compared to other dopamine receptor subtypes and had moderate affinity for 5HT2, sigma and alpha adrenergic receptors(IC50 < 300 nM). In vitro, L-745,870 (0.1-1 microM) exhibited D4 receptor antagonist activity, reversing dopamine (1 microM) mediated 1) inhibition of adenylate cyclase in hD4HEK and hD4CHO cells; 2) stimulation of [35S] GTPgammaS binding and 3) stimulation of extracellular acidification rate, but did not exhibit any significant intrinsic activity in these assays. Although standard antipsychotics increase dopamine metabolism or plasma prolactin levels in rodents, L-745,870 (</=30 mg/kg p.o.) had no effect in these assays. The lack of a suitable in vivo assay for D4 receptor activation prompted the use of in vivo surrogate marker assays which confirmed that doses of 5-60 microg/kg L-745,870 would be sufficient to occupy 50% D4 receptors in the brain. These results show that dopamine D4 receptor antagonism in the brain does not result in the same neurochemical consequences (increased dopamine metabolism or hyperprolactinemia) observed with typical neuroleptics.

5-(Piperidin-2-yl)- and 5-(homopiperidin-2-yl)-1,4-benzodiazepines: high-affinity, basic ligands for the cholecystokinin-B receptor

The design, synthesis, and biological activity of a series of high-affinity, basic ligands for the cholecystokinin-B receptor are described. The compounds, which incorporate a piperidin-2-yl or a homopiperidin-2-yl group attached to C5 of a benzodiazepine core structure, are substantially more basic (e.g., 9d, pKa = 9.48) than previously reported antagonists based on 5-amino-1,4-benzodiazepines (e.g., 5, pKa = 7.1) and have improved aqueous solubility. In view of their basicity, it would be tempting to speculate that the present series of compounds might be binding to the CCK-B receptor in their protonated form. Compounds such as 9d, e and 10d showed high affinity for this receptor (IC50 < 2.5 nM) and very good selectivity over CCK-A (CCK-A/CCK-B > 2000), even as the racemates. Additionally, a significantly improved in vivo half-life was observed for a selection of compounds compared to the clinical candidate L-365, -260 (1).

Are radioligand antagonist/agonist binding ratios in rat pancreas predictive of functional efficacy of cholecystokinin receptor agonists and antagonists?

Radioligand binding assays have been previously used to predict the relative efficacy of novel ligands. In the present study we have investigated whether for the cholecystokinin CCK-A receptors in the rat pancreas, the ratio of binding affinities for compounds for antagonist and agonist radioligands are predictive of functional activity. A number of classical cholecystokinin agonists, such as CCK-8S, caerulein, CCK-8DS, pentagastrin and CCK-4 had antagonist/agonist binding ratios of 4-fold or greater. All compounds behaved as full agonists in the stimulation of phosphatidylinositol (PI) turnover and increase in amylase secretion in rat pancreas. In contrast, compounds such as the benzodiazepine derivatives devazepide and L-365,260 had binding ratios of less than one and lacked agonist activity in either functional assay. Interestingly, the dipeptide derivative CI-988, which has been described as a selective CCK-B antagonist, was found to have an antagonist/agonist binding ratio of 1.5 for the CCK-A receptors in rat pancreas which was sufficiently high for this compound to behave as a full agonist in the amylase assay, although CI-988 did not exhibit agonist activity in the PI assay. These results suggest that the effective receptor reserve in the amylase assay is greater than that required to stimulate PI turnover, and that the selective peptoid CCK-B antagonist CI-988 has weak agonist activity at CCK-A receptors.

Controlled modification of acidity in cholecystokinin B receptor antagonists: N-(1,4-benzodiazepin-3-yl)-N'-[3-(tetrazol-5-ylamino) phenyl]ureas

The design, synthesis, and biological activity of a novel series of CCK-B receptor antagonists (1) which incorporate a tetrazol-5-ylamino functionality attached to the phenyl ring of the arylurea moiety of L-365,260 are described. In these compounds, the acidity of the tetrazole was gradually modified by utilization of simple conformational constraints, and X-ray crystallographic data were obtained to support the conformational depenence of the pK(a) of the aminotetrazoles. Compounds to emerge from the present work such as 1f and 2c,d are among the highest affinity and, in the case of 1f, most selective (CCK-A/CCK-B, 37 000) antagonists so far reported for this receptor. The C(5)-cyclohexyl compound 2c (L-736,380) dose-dependently inhibited gastric acid secretion in anesthetized rats (ID(50), 0.064 mg/kg) and ex vivo binding of [(125)I]CCK-8S in BKTO mice brain membranes (ED(50), 1.7 mg/kg) and is one of the most potent acidic CCK-B receptor antagonists yet described.

Biological properties of the benzodiazepine amidine derivative L-740,093, a cholecystokinin-B/gastrin receptor antagonist with high affinity in vitro and high potency in vivo

A novel series of 5-amino-1,4-benzodiazepin-2-one derivatives (amidines), which contain a cationic solubilizing group and which are antagonists for the cholecystokinin (CCK)-B receptor, have been identified. Optimization of this series led to the identification of an azabicyclononane amidine, L-740,093 [N-[(3R)-5-(3-azabicyclo[3.2.2]nonan-3-yl)-2,3-dihydro-1-methyl-2- oxo- 1H-1,4-benzodiazepin-3-yl]-N'-(3-methylphenyl)urea], that bound with high affinity of CCK-B receptors from guinea pig cerebral cortex (IC50 of 0.1 nM) and had a CCK-B/CCK-A receptor selectivity of 16,000. In comparison, L-365,260 had 85-fold lower affinity (8.5 nM) and was only 87-fold selective for CCK-B over CCK-A receptors. L-740,093 bound with high affinity to guinea pig gastrin receptors in vitro (IC50 of 0.04 nM). Electrophysiological studies on slices of rat ventromedial hypothalamic nucleus showed that L-740,093 produced rightward shifts of the concentration-response curve for the CCK-B receptor agonist pentagastrin (Kb of 0.06 nM). L-740,093 blocked pentagastrin-induced gastric acid secretion in anesthetized rats with a 50% inhibitory dose of 0.01 mg/kg, intraperitoneally, showing 100-fold greater activity, compared with L-365,260 (50% inhibitory dose of 1 mg/kg, intraperitoneally). An ex vivo binding assay in mice was used to investigate the interaction of L-740,093 with central CCK binding sites. After intravenous administration, L-740,093 inhibited ex vivo binding dose dependently, with a 50% effective dose of 0.2 mg/kg. These studies demonstrate that L-740,093 is the most potent and selective CCK-B antagonist yet described and that it has excellent central nervous system penetration.

Selective non-peptide ligands for an accommodating peptide receptor. Imidazobenzodiazepines as potent cholecystokinin type B receptor antagonists

A series of imidazobenzodiazepines, non-peptide antagonists of the peptide hormone cholecystokinin (CCK), are described. Derived by chemical modification of the benzodiazepine ring system embedded within the CCK-B antagonist L-365,260, these compounds display CCK-B/CCK-A selectivity and some analogs have receptor binding affinities in the subnanomolar range. This group of novel imidazobenzodiazepines, among which N-[(2S,4R)-methyl-6-phenyl-2,4-dihydro-1H-imidazo[1,2- alpha][1,4]benzodiazepin-4-yl]-N'-[3-methylphenyl]-urea (12) is the principal compound, expands the structural diversity of the collection of non-peptide CCK-B antagonists and will be useful in further delineating the function of CCK in the central nervous system.

Measurement of central nervous system activity of systemically administered CCKB receptor antagonists by ex vivo binding

In the present study we have described an ex vivo binding assay in mice to measure the central nervous system (CNS) activity of systemically administered CCKB receptor antagonists. This assay incorporated a transcardiac perfusion step to remove the residual blood from the brain, which otherwise may result in an overestimation of CNS activity. The benzodiazepine CCKB receptor antagonist L-365,260 had marked CNS activity in this assay following i.v. (ED50 12.0 mg/kg) and p.o. (ED50 20.0 mg/kg) administration, whereas the dipeptoid CCKB receptor antagonist, CI988 exhibited relatively weak CNS activity following i.v. injection (ED50 > 30.0 mg/kg). In contrast, following i.c.v. administration, CI988 potently inhibited ex vivo binding of [125I]Bolton Hunter-CCK-8S to mouse brain. The recently described acidic tetrazole CCKB receptor antagonist, L-368,935 had potent CNS activity with an ED50 of 5.6 mg/kg i.v. and an ED50 of 1.9 micrograms/kg i.c.v. These studies suggest that the weak CNS activity of CI988 following systemic injection may, in part, be due to poor brain penetration and that the ex vivo binding assay is a useful way of assessing the brain penetration of CCKB receptor antagonists.

Identification of children with and without cleft palate from tape-recorded samples of early vocalizations and speech

Thirty judges (5 speech pathologists, 10 mothers of children with cleft palate, and 15 mothers of noncleft children) listened to 90 tape-recorded samples of early vocalizations/speech obtained from noncleft babies and babies with cleft palate. Each sample was classified by the judges as normal or abnormal. As a group, the speech pathologists classified only 60% of the cleft samples as abnormal and 59% of the normal samples as normal. The cleft and noncleft mother groups, on the other hand, classified 37% and 25% of the cleft samples as abnormal and 59% and 73% of the normal samples as normal. Poor interjudge agreement was evident within and across the three groups of judges. The poor reliability demonstrated by the speech pathologists in identifying babies with unrepaired clefts appeared related more to a difference in interpretation of the perceptual data than an inability to hear salient information.

Phonologic processes in children with cleft palate

This study examined the phonologic process usage of 3-, 4- and 5-year-old children with cleft palate. Sixty children served as subjects: 30 children with cleft palate (with or without cleft lip) and 30 noncleft palate children. The children's whole word productions were analyzed for frequency and type of phonologic process usage. Results indicated that the 3- and 4-year old children with cleft palate exhibited more instances of process usage, compared to their noncleft peers. The 5-year-old cleft and noncleft groups were similar in total instances of process usage. Further, the children with cleft palate employed common phonologic processes; however, some processes were noted more frequently in the speech of the 3-year-old children with cleft palate.

Phonetic and phonologic skills of two-year-olds with cleft palate

This article examines the phonetic and phonologic skills of 2-year-olds with cleft palate. Fifteen children, 10 children with cleft palate and five noncleft children, participated in the study. The children with cleft palate all received palatal surgery after 12 months of age and after the onset of meaningful speech. All subjects were video and audiotaped while interacting with their mothers during unstructured play. At least one hundred different spontaneous word productions were phonetically transcribed and analyzed for (1) percent consonants correct, (2) phonologic processes, and (3) "compensatory" articulation patterns. A comparison between the groups indicated that although the children with cleft palate exhibited more errors overall, they were similar to their noncleft peers in their phonologic process usage with two exceptions. Additionally, few "compensatory" articulation errors were noted in the speech of these children.

Vocalizations of toddlers with cleft lip and palate

This study examined the early vocalizations of toddlers with cleft lip and palate. Ten toddlers, ranging in age from 12 to 14 months, served as subjects: five toddlers with cleft lip and palate and five noncleft toddlers. Samples of the toddler's spontaneous vocalizations were obtained while they interacted with their mothers during an unstructured play session. All speech-like vocalizations were transcribed, and comparisons were made between the cleft and noncleft groups for (1) size of consonant inventory, (2) type and frequency of occurrence of consonants, and (3) frequency and type of multisyllabic productions. Results indicated differences in the consonant inventories and multisyllabic productions of the two groups of toddlers.

Language input of mothers interacting with their young children with cleft lip and palate

Maternal language addressed to 1-, 2-, and 3-year-old children with cleft lip and palate was studied. Videotaped interactions were obtained from 23 mother-child dyads (13 mother-cleft lip and palate child dyads, and 13 mother noncleft child dyads) during free play. Results indicated more similarities than differences in maternal language characteristics for the two groups of mothers.

Studies that question the existence of alpha-2 adrenoceptors in tail arteries of normotensive Sprague-Dawley rats

Many pharmacological studies have demonstrated two distinct types of alpha adrenoceptor in the vasculature; these receptors have been named alpha-1 and alpha-2. In the present study, using isolated perfused tail arteries from normotensive Sprague-Dawley rats, we have demonstrated two types of alpha adrenoceptor but neither of these could be classified as an alpha-2 adrenoceptor. Dose-dependent contraction of rat tail arteries was produced by the following alpha adrenoceptor agonists or agonist-antagonist combination: phenylephrine (PE alpha-1), clonidine (alpha-1 and alpha-2), clonidine in the presence of 10(-7) M prazosin (alpha-2) and BHT-920 (alpha-2). The ED50 values for PE and clonidine were four orders of magnitude lower than those for clonidine plus prazosin and BHT-920. In addition, the action of PE was faster in onset than that of BHT-920, reached a higher maximum (5-fold) and attenuated more rapidly than that of BHT-920. The specific alpha-2 adrenoceptor antagonist yohimbine, in concentrations as high as 10(-6) M, did not antagonize arterial responses to BHT-920. However, responses to BHT-920 were antagonized by the alpha-1 adrenoceptor antagonist prazosin, in concentrations as low as 10(-10) M, and by the serotonin/alpha-1 adrenoceptor antagonist ketanserin (10(-7) M). These results suggest that the two alpha-adrenoceptor types in isolated rat tail arteries are both of the alpha-1 type. We also found that whereas responses to PE were stable and reproducible between 2 and 5 hr of arterial perfusion, responses to BHT-920 increased progressively over 5 hr. The latter effect probably resulted from a gradual disappearance of the arterial endothelium.

Investigations into the nature of alpha 2-adrenoceptors in rat tail arteries

In rat isolated perfused tail arteries, dose-response curves were established for the vasopressor effects of phenylephrine (alpha 1-adrenoceptor agonist), clonidine (alpha 1- and alpha 2-adrenoceptor agonist), clonidine in the presence of 10(-7) mol/l prazosin (alpha 2-agonist), and BHT-920 (alpha 2-agonist). The ED50 values were: phenylephrine 1.85 X 10(-10) mol; clonidine 6.3 X 10(-10) mol; clonidine + prazosin 3.2 X 10(-6) mol; BHT-920 6.1 X 10(-6) mol. The arterial reactivity to BHT-920 was stable only after 4-5 h of perfusion. Responses to BHT-920 were not antagonized by yohimbine (alpha 2-adrenoceptor antagonist) but were antagonized by low concentrations of prazosin (alpha 1-adrenoceptor antagonist). These data constitute conflicting evidence regarding the existence of alpha 2-adrenoceptors in rat tail arteries. The data are consistent with the proposal that there are two recognition sites on alpha 1-adrenoceptors; phenylephrine and BHT-920 may stimulate different sites on alpha 1-adrenoceptors.