What Do Patients Look for When Scheduling Their Initial Elective Aesthetic Plastic Surgery Consultation?

BACKGROUND

Multiple factors influence patients when deciding on where to seek plastic surgery consultations. Our objective was to determine the most important factors when booking the initial consultation.

METHODS

A 23 question survey was distributed online via Amazon Mechanical Turk targeting participants who had prior plastic surgery consultations or were planning to have one in the future. Participant demographic data were collected, and participants were asked to rank the importance of factors related to cost, surgeon reputation, social media, technology, amenities, accessibility, and appointment details on a 1-5 Likert scale. Rankings were reported by mean and standard deviation.

RESULTS

A total of 593 responses were gathered. 48.1% of participants were 25-34 years of age, 54.6% were female, 66.3% identified as White, 78.4% were located in the U.S, and 54.5% had a bachelor's degree. Participants rated the importance of a surgeon's online reviews (mean 4.15, SD 0.81), surgeon presence at follow-up visits (mean 4.01, SD 0.91), and availability of pricing prior to appointment (mean 4.01, SD 0.91) the highest. The least important factors were waiting room amenities and social media advertising. Individuals younger than 45 were more likely to rate a surgeon's social media presence higher than those 45 years and older (OR 2.02; 95%CI [1.37-2.96]; p < 0.001).

CONCLUSIONS

Patients considered surgeon's online reviews, presence at follow-up visits, and the availability of pricing information the most important when booking a plastic surgery consultation. These findings may assist physicians in structuring plastic surgery consultations based on factors important to patients.

LEVEL OF EVIDENCE V

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Timing of autologous fat grafting in implant-based breast reconstruction: Best practices based on systematic review and meta-analysis

BACKGROUND

Fat grafting is commonly undertaken as a third-stage procedure in patients with staged implant-based breast reconstruction (IBR). However, fat grafting performed during second-stage expander/implant exchange provides faster results without an additional procedure and associated risks (Patel et al., 2020). We previously demonstrated that fat grafting during second-stage expander/implant exchange did not increase clinical complications (Patel et al., 2020). As a corollary, this study investigates patients' satisfaction with second- versus third-stage fat grafting to help establish a set of best practices for the timing of fat grafting in such patients.

METHODS

A review of PubMed/MEDLINE databases (2010-2022) was performed to identify articles investigating the quality of life in patients undergoing second- or third-stage fat grafting after IBR. BREAST-Q scores were pooled using random-effects modeling and the DerSimonian-Laird method. Post-hoc sensitivity analyses were completed using the Hartung-Knapp-Sidik-Jonkman method. The Haldane-Anscombe correction was used for outcomes with low counts. All study analyses adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

Six studies (216 patients) were included. Pooled random-effects modeling demonstrated no significant changes in BREAST-Q satisfaction with outcome scores when comparing patients who received second- versus third-stage fat grafting (p = 0.178) with results robust to sensitivity analyses. In addition, pooled analyses of the available data demonstrated that second-stage fat grafting did not increase downstream revision surgery needs compared to third-stage fat grafting.

CONCLUSIONS

In combination with our prior work, this meta-analysis suggests that second-stage fat grafting provides not only equivalent but improved clinical and quality of life outcomes with fewer procedures in patients undergoing expander/IBR.

Racial Disparities in Postoperative Breast Reconstruction Outcomes: A National Analysis

BACKGROUND

Studies have shown that Black patients are more likely to experience complications following breast reconstruction compared to other racial groups. Most of these studies have been conducted on patient populations focusing on either autologous or implant-based reconstruction without possible predictive indicators for complication disparities for all types of reconstruction procedures. The aim of this study is to elucidate disparities among patient demographics by identifying predictors of complications and postoperative outcomes among different racial/ethnic patients undergoing breast reconstruction utilizing multi-state, multi-institution, and national level data.

METHODS

Patients in the Optum Clinformatics Data Mart that underwent all billable forms of breast reconstruction were identified via CPT codes. Demographics, medical history, and postoperative outcome data were collected by querying relevant reports of CPT, ICD-9, and ICD-10 codes. Outcomes analysis was limited to the 90-day global postoperative period. A multivariable logistic-regression analysis was performed to ascertain the effects of age, patient reported ethnicity, coexisting conditions, and reconstruction type on the likelihood of any common postoperative complication occurring. Linearity of the continuous variables with respect to the logit of the dependent variable was confirmed. Odds ratios and corresponding 95% confidence intervals were calculated.

RESULTS

From over 86 million longitudinal patient records, our study population included 104,714 encounters for 57,468 patients who had undergone breast reconstruction between January 2003 and June 2019. Black race (relative to White), autologous reconstruction, hypertension, type II diabetes mellitus, and tobacco use were independent predictors of increased likelihood of complication. Specifically, the odds ratios for complication occurrence for Black, Hispanic, and Asian ethnicity (relative to White) were 1.09, 1.03, and 0.77, respectively. Black patients had an overall breast reconstruction complication rate of 20.4%, while the corresponding rate for White, Hispanic, and Asian patients were 17.0%, 17.9%, and 13.2%, respectively.

CONCLUSION

Our analysis of a national-level database shows that Black patients undergoing implant-based or autologous reconstruction have increased risk of complications, likely due to multifactorial components that play a role in the care of this patient population. While higher rates of comorbidities have been cited as a possible cause, providers must consider racial influences involving cultural context, historical mistrust in medicine, and physician/health institution factors that may drive this disparity of outcomes among our patients.

Optimizing postoperative outcomes following neoadjuvant chemotherapy and mastectomy with immediate reconstruction: A national analysis

BACKGROUND

The optimal timing between last neoadjuvant chemotherapy (NAC) session and mastectomy with immediate reconstruction (MIR) procedures has sparse data to support optimization of postoperative outcomes. Current literature suggests that timing is not a predictor of complications in patients undergoing implant-based reconstruction following NAC and other literature suggests guidelines based on tumor staging. To the best of our knowledge, this is the largest and most recent study characterizing the effect of time between NAC and mastectomy with immediate reconstruction on postoperative complications.

METHODS

Patients in the Optum Clinformatics Data Mart that underwent all billable forms of breast reconstruction following NAC were identified via CPT and ICD-10 codes. Data concerning these patient's demographics, comorbidities, oncologic treatment, and outcomes were collected by querying relevant reports of CPT, ICD-9, and ICD-10 codes. To meet inclusion criteria, patients needed to have an encounter for antineoplastic chemotherapy within 1 year of their associated reconstruction. Patients with other invasive procedures unrelated to their mastectomy-reconstruction pairing within 90 days of reconstruction were excluded. Outcomes analysis was limited to the 90-day postoperative period. The time between the last recorded chemotherapy encounter and breast reconstruction was computed. A multivariate logistic regression analysis was performed to ascertain the effects of age, race, coexisting conditions, reconstruction type (autologous or implant-based), and time between NAC and reconstruction on the likelihood of any common postoperative complication occurring. Linearity of the continuous variables with respect to the logit of the dependent variable was confirmed. Odds ratios and corresponding 95% confidence intervals were calculated.

RESULTS

From over 86 million longitudinal patient records, our study population included 139 897 4371 patient records corresponding to 13 399 3759 patients who had NAC and breast reconstruction between January 2003, October 2015, and June 2019. Increased time between last antineoplastic chemotherapy and MIR reconstruction was a statistically significant, independent predictor of decreased complication likelihood. By contrast, autologous reconstruction, hypertension, and type II diabetes mellitus, and African American, White, and Hispanic race (relative to Asian) had statistically significant associations with increased complication likelihood. Waiting an additional day between a patient's most recent chemotherapy session and MIR reconstruction reduces the odds of a complication occurring by 0.25%. This corresponds to reduction in odds of complication occurrence of approximately 7% for each month between neoadjuvant therapy and breast reconstruction.

CONCLUSION

Increased time between NAC and MIR immediate reconstruction decreases the likelihood of experiencing one or more postoperative complications. Ideal time delay between 4 and 8 weeks has been shown to provide the best benefit for future breast reconstrution outcomes. In consultation with the oncologist, this information can be used to balance postoperative complication risk with increased oncologic risk in delaying mastectomy with immediate reconstruction.

#PRS: A Study of Plastic Surgery Trends With the Rise of Instagram

Background

Instagram (Menlo Park, CA) has become a popular means of advertisement for aesthetic surgery procedures, influencing patients' likelihood of undergoing a procedure. In this study, the authors aim to explore public interest in aesthetic procedures before and after the Instagram platform started gaining in popularity through Google Trends (Google, Mountain View, CA), a platform with previously demonstrated utility for tracking interest in surgical procedures.

Objectives

The authors hypothesize that as a result of increased medical marketing on Instagram, there is an increase in public interest in elective procedures of plastic surgery.

Methods

Trends in the United States for given search terms and volumes were gathered through Google Trends between April 2004 and January 2022. Search terms included popular aesthetic procedures based on the 2020 Aesthetic Plastic Surgery National Data Bank Statistics. The search volumes were normalized, and a bivariate regression analysis of panel data was then applied to the aggregate trendlines to determine whether a statistically significant change in search volume occurred following the increase in user traffic of the Instagram platform.

Results

The authors found significant variations in search volume for plastic surgery procedures before and after April 2012. Blepharoplasty, Botox, brachioplasty, breast implant removal, breast reduction, brow lift, butt lift, hair transplantation, lip augmentation, male breast surgery, mastopexy, mentoplasty, otoplasty, platysmaplasty, rhinoplasty, and thighplasty (P < .000) had statistically significant increases in search volume, whereas buccal fat removal (P = .003) had a statistically significant decrease in search volume after April 2012.

Conclusions

The authors observed a significant increase in public interest in both surgical and nonsurgical aesthetic procedures after Instagram gained popularity in the April of 2012.

Criteria for Elective Admission to the Paediatric Intensive Care Unit following Adenotonsillectomy for Severe Obstructive Sleep Apnoea

During the period 1997 to 2002, 42 children were electively admitted to the Paediatric Intensive Care Unit at the John Hunter Children's Hospital following adenotonsillectomy for severe obstructive sleep apnoea. Forty children had a preoperative sleep study, of which 33 were complete polysomnograms. Of the 42 children admitted, 35 required no intervention while seven (17%) required an additional intervention beyond supplemental oxygen. Our criteria for elective admission to Paediatric Intensive Care following adenotonsillectomy for severe obstructive sleep apnoea are presented.

Severe Hypothermia: Challenging Normal Physiology

Accidental hypothermia is not a frequent cause of death in Australia. Moreover it is rare to have an admission to hospital with a core temperature below 32°C. Among the cases described in the literature, it is clear that temperature and prognosis are related. Our patient presented with severe accidental hypothermia and even though the admission core temperature was below 26 degrees she was successfully discharged from hospital after active re-warming with three different devices. She had laboratory and ECG findings associated with severe hypothermia.

Postoperative Euglycaemic Diabetic Ketoacidosis Associated with Sodium–Glucose Cotransporter-2 Inhibitors (Gliflozins): A Report of Two Cases and Review of the Literature

Sodium–glucose cotransporter-2 inhibitor (SGLT2i)-associated euglycaemic diabetic ketoacidosis (euDKA) is a serious and increasingly recognised complication of treatment with this class of oral hypoglycaemic agents and can present a diagnostic challenge, resulting in delayed recognition, inappropriate treatment and potentially life-threatening acidosis. We present two cases of patients developing SGLT2i-associated euDKA in the early postoperative period. We support ceasing SGLT2i for 72 hours preoperatively and would suggest continuing to withhold the medication until oral intake is restored, and recommend a wider awareness of SGLT2i-associated diabetic ketoacidosis (DKA) amongst patients and their healthcare providers with an emphasis on checking ketone levels irrespective of blood glucose levels in the postoperative setting.

A latent class model for competing risks

Survival data analysis becomes complex when the proportional hazards assumption is violated at population level or when crude hazard rates are no longer estimators of marginal ones. We develop a Bayesian survival analysis method to deal with these situations, on the basis of assuming that the complexities are induced by latent cohort or disease heterogeneity that is not captured by covariates and that proportional hazards hold at the level of individuals. This leads to a description from which risk-specific marginal hazard rates and survival functions are fully accessible, 'decontaminated' of the effects of informative censoring, and which includes Cox, random effects and latent class models as special cases. Simulated data confirm that our approach can map a cohort's substructure and remove heterogeneity-induced informative censoring effects. Application to data from the Uppsala Longitudinal Study of Adult Men cohort leads to plausible alternative explanations for previous counter-intuitive inferences on prostate cancer. The importance of managing cardiovascular disease as a comorbidity in women diagnosed with breast cancer is suggested on application to data from the Swedish Apolipoprotein Mortality Risk Study. Copyright © 2017 John Wiley & Sons, Ltd.

Adolescents’ judgements about the evidential basis for complex beliefs

Participants aged between 13 and 60 years read vignettes describing conflicting interpretations of limited evidence, explained why the different interpretations arose, and judged the importance of further evidence in resolving the dispute. Our focus was on participants’ views about how minds interpret information: Was their emphasis more on internal, psychological, or on external, information-based, factors in accounting for the existence of different interpretations? Participants of all ages agreed that further evidence would not be sufficient to resolve a value-laden dispute (whether youngsters should learn to drive) and explained the different views in terms of internal factors. However, younger participants discriminated less than older ones between the driving dispute and a dispute about a scientific/medical issue (the cause of a skin disease), and were less inclined to judge that views about the skin disease would be influenced by further evidence. We suggest that among people who accept the possibility of different interpretations of the same information, there are age-related differences in the importance placed on internal psychological processes in the construction of disparate views. Adolescents, compared with people who are older, seem to be particularly prone to assume that idiosyncratic interpretations will persist.

Abstract P5-07-06: A competing risks analysis of the association between prediagnostic serum glucose and lipids and breast cancer survival

Background: Abnormal levels of glucose and lipids may be linked to survival after breast cancer (BC) diagnosis, but their association to other causes of mortality such as cardiovascular (CV) disease may result in a competing risk problem and invalidate conventional analyses.

Methods: We assessed serum glucose, triglycerides (TG) and total cholesterol (TC) measured prospectively three months to three years before diagnosis in 1,798 women with BC in the Swedish Apolipoprotein Mortality Risk Study (AMORIS). In addition to using multivariable Cox proportional hazards regression, we employed latent class proportional hazards models to capture any heterogeneity of associations between these markers and BC death. The latter method was extended to include the primary outcome (BC death) and competing outcomes (CV death and death from other causes), allowing latent class-specific hazard estimation for cause-specific deaths.

Results: No association between prediagnostic glucose, TG or TC with BC death was observed with Cox regression. With latent class proportional hazards model, two latent classes (Class I and II) were identified in the cohort. Class I, comprising the majority (81.5%) of BC patients, had an increased risk of BC death following higher TG levels (HR: 1.87, 95% CI: 1.01-3.45 for every log TG increase). Lower overall survival was observed in Class II, but no association for BC death was found. On the other hand, TC positively corresponded to CV death in Class II, and similarly, glucose to death from other causes.

Conclusion: Higher TG was associated with an increased risk of BC death in the majority of BC patients. Our study also identified a subgroup of BC patients at higher risk of early death likely driven by other metabolic-related diseases, which adds to our understanding into BC survival in presence of competing outcomes.

Citation Format: Wulaningsih W, Vahdaninia M, Rowley M, Holmberg L, Garmo H, Malmstrom H, Lambe M, Hammar N, Walldius G, Jungner I, Coolen A, Van Hemelrijck M. A competing risks analysis of the association between prediagnostic serum glucose and lipids and breast cancer survival. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-07-06.

Platelet transfusions in haematology patients: are we using them appropriately?

BACKGROUND AND OBJECTIVES

A large proportion of all platelet components are given to haematology patients. As there are risks associated with their transfusion, costs associated with production, and shortages may occur, it is important that their use is appropriate.

STUDY DESIGN AND METHODS

The study was split into two parts, a survey to assess local practice guidelines and an assessment of platelet usage. A total of 123 hospitals completed the survey and 168 hospitals submitted data of 40 haematology patients over a 3-month period.

RESULTS

The organizational survey found that 36% of hospitals routinely give prophylactic platelet transfusions to patients with long-term bone-marrow failure. Also, a significant minority of hospitals administer platelet transfusions if the platelet count is below a certain threshold prior to performing a bone-marrow aspirate (11%) or a bone-marrow aspirate and trephine (23%); both of these are contrary to UK platelet transfusion guidelines. Data were collected on a total of 3402 patients, of which 3296 cases were eligible for analysis. They received approximately 46% of all platelet components issued to participating hospitals in England during the study period. The majority (69%) of platelet transfusions were prophylactic; of these only 33% were given when the platelet count was ≤10×10(9)/l. Using an algorithm, based on current UK guidelines, 60% of prophylactic transfusions were appropriate, 6% could not be assessed and 34% were inappropriate. A total of 10% of all prophylactic transfusions were double the standard adult dose.

CONCLUSIONS

There is considerable potential for decreased use of platelet transfusions with a consequent improvement in their appropriate use and cost reduction.

Cryoprecipitate for transfusion: which patients receive it and why? A study of patterns of use across three regions in England

BACKGROUND

Despite increasing interest in the use of fibrinogen concentrates, cryoprecipitate remains the major source of fibrinogen in England.

OBJECTIVES

Understand patterns and indications for use of cryoprecipitate in hospitals from three English regions.

METHOD/MATERIALS

Data collection over 3 months from adults, children and neonates receiving cryoprecipitate, including clinical scenario, indications, dose and levels of fibrinogen concentrations pre- and post-transfusion.

RESULTS

Four hundred and twenty-three episodes of cryoprecipitate transfusion were analysed from 39 hospitals. Use varied from 0.1 to 4.9 units per 100 red cells transfused. The primary indication was haemorrhage [311 episodes (74%)]. The commonest clinical scenario in all age groups was cardiac surgery, followed by trauma in adults and critical/neonatal care for children. Pre-treatment fibrinogen levels were measured in 322 episodes. In 179 episodes, the level was ≥ 1.0 g L(-1) .

CONCLUSION

Wide variation in practice and dose suggests inconsistent practice and uncertainty in the evidence informing optimal use of cryoprecipitate.

A Bayesian method for single molecule, fluorescence burst analysis

There is currently great interest in determining physical parameters, e.g. fluorescence lifetime, of individual molecules that inform on environmental conditions, whilst avoiding the artefacts of ensemble averaging. Protein interactions, molecular dynamics and sub-species can all be studied. In a burst integrated fluorescence lifetime (BIFL) experiment, identification of fluorescent bursts from single molecules above background detection is a problem. This paper presents a Bayesian method for burst identification based on model selection and demonstrates the detection of bursts consisting of 10% signal amplitude. The method also estimates the fluorescence lifetime (and its error) from the burst data.

Metabolism-related liabilities of a potent histone deacetylase (HDAC) inhibitor and relevance of the route of administration on its metabolic fate

Compound A [1-methyl-N-{(1S)-1-[5-(2-naphthyl)-1H-imidazol-2-yl]-7-oxooctyl}piperidine-4-carboxamide is a potent class I histone deacetylase (HDAC) inhibitor that demonstrated good antiproliferative activity against human tumour cell lines of different origin. This compound showed high in vivo clearance in rats (160 ml min(-1) kg(-1)) due to metabolism. The main metabolite detected in urine after intravenous dosing was characterized as a dihydrohydroxy S-mercapturic acid conjugate. Following oral dosing, however, the mercapturic acid derivative was no longer the main metabolite but the major metabolites were mono- and di-glucuronide conjugates of oxidized species having a mass shift of +34 m/z with respect to the parent. Comparison of plasma concentration after intra-arterial infusion and intravenous infusion and incubation with microsomes from different tissues (liver, kidney, small intestine and lung) in the presence of beta-nicotinamide adenine dinucleotide phosphate (NADPH) indicated that the compound was highly cleared by the lung. Oxidation of the naphthalene moiety was demonstrated to be the cause of the high in vivo clearance of compound A and the potential for bioactivation of this group was flagged.

Studies of metabolism and disposition of potent human immunodeficiency virus (HIV) integrase inhibitors using19F-NMR spectroscopy

(19)F-nuclear magnetic resonance (NMR) has been extensively used in a drug-discovery programme to support the selection of candidates for further development. Data on an early lead compound, N-(4-fluorobenzyl)-5-hydroxy-1-methyl-2-(4-methylmorpholin-3-yl)-6-oxo-1,6-dihydropyrimidine-4-carboxamide (compound A (+)), and MK-0518 (N-(4-fluorobenzyl)-5-hydroxy-1-methyl-2-(1-methyl-1-{[(5-methyl-1,3,4-oxadiazol-2-yl)carbonyl]amino}ethyl)-6-oxo-1,6-dihydropyrimidine-4-carboxamide), a potent inhibitor of this series currently in phase III clinical trials, are described. The metabolic fate and excretion balance of compound A (+) and MK-0518 were investigated in rats and dogs following intravenous and oral dosing using a combination of (19)F-NMR-monitored enzyme hydrolysis and solid-phase extraction chromatography and NMR spectroscopy (SPEC-NMR). Dosing with the (3)H-labelled compound A (+) enabled the comparison of standard radiochemical analysis with (19)F-NMR spectroscopy to obtain quantitative metabolism and excretion data. Both compounds were eliminated mainly by metabolism. The major metabolite identified in rat urine and bile and in dog urine was the 5-O-glucuronide.

Preclinical pharmacokinetics and metabolism of a potent non-nucleoside inhibitor of the hepatitis C virus NS5B polymerase

The disposition of compound A, a potent inhibitor of the hepatitis C virus (HCV) NS5B polymerase, was characterized in animals in support of its selection for further development. Compound A exhibited marked species differences in pharmacokinetics. Plasma clearance was 44 ml min-1 kg-1 in rats, 9 ml min-1 kg-1 in dogs and 16 ml min-1 kg-1 in rhesus monkeys. Oral bioavailability was low in rats (10%) but significantly higher in dogs (52%) and monkeys (26%). Compound A was eliminated primarily by metabolism in rats, with biliary excretion accounting for 30% of its clearance. Metabolism was mainly mediated by cyclohexyl hydroxylation, with N-deethylation and acyl glucuronide formation constituting minor metabolic pathways. Qualitatively, the same metabolites were identified using in vitro systems from all species studied, including humans. The low oral bioavailability of compound A in rats was mostly due to poor intestinal absorption. This conclusion was borne out by the findings that hepatic extraction in the rat was only 30%, intraperitoneal bioavailability was good, and compound A was poorly absorbed from the rat isolated intestinal loop, with no detectable intestinal metabolism. Compound A was not an inhibitor of major human cytochrome P450 enzymes, indicating minimal potential for clinical drug-drug interactions. The metabolic clearance of compound A in rat, dog and monkey hepatocytes correlated with the systemic clearance observed in these species. Since compound A was very stable in human hepatocytes, the results suggest that it will be a low clearance drug in humans.

Severe gestational (incidental) thrombocytopenia: to treat or not to treat

Thrombocytopenia is common in pregnancy and is diverse in etiology. Immune thrombocytopenic purpura (ITP) may affect both mother and the newborn. Gestational (incidental) thrombocytopenia in an otherwise fit woman, at term is the most frequent type of thrombocytopenia and poses no clinical consequences for mother or infant. We report six women who presented with severe thrombocytopenia during pregnancy. Five were treated in late pregnancy, either with intravenous immunoglobulin (IVIg), or IVIg followed by steroids. There was no response, and four received a platelet transfusion during delivery. The platelet counts in all the infants were normal and the maternal thrombocytopenia resolved spontaneously after delivery in all cases. Our observations suggest that this is a group of patients with a severe form of gestational thrombocytopenia. The severe form of gestational thrombocytopenia appears to be rare, and recognition is important, as it may recur in subsequent pregnancies and does not require any therapeutic intervention.

Remission induced by Campath-1H for thymoma-associated agranulocytosis

Thymoma-associated agranulocytosis is a rare but almost universally fatal condition. Reports to date have described several immunosuppressive therapies including steroids, cyclophosphamide and vincristine as adjuvants to thymectomy, in an effort to improve neutropenia. We report the response to the monoclonal antibody Campath-1H of a patient with a thymoma and associated agranulocytosis with complete absence of bone marrow granulocyte precursors, which had failed to respond to thymectomy. Treatment with Campath-1H resulted in complete responses of promising durability sustained with the addition of cyclosporin and mycophenolate mofetil as maintenance therapy.

3-(4-Fluoropiperidin-3-yl)-2-phenylindoles as high affinity, selective, and orally bioavailable h5-HT(2A) receptor antagonists

The development of very high affinity, selective, and bioavailable h5-HT(2A) receptor antagonists is described. By investigation of the optimal position for the basic nitrogen in a series of 2-phenyl-3-piperidylindoles, it was found that with the basic nitrogen at the 3-position of the piperidine it was not necessary to further substitute the piperidine in order to obtain good binding at h5-HT(2A) receptors. This meant the compounds no longer had high affinity at the IKr potassium channel, an issue with previous series of 2-aryl-3-(4-piperidyl)indoles. Improvements could be made to oral bioavailability in this series by reduction of the pK(a) of the basic nitrogen, by adding a fluorine atom to the piperidine ring, leading to 3-(4-fluoropiperidin-3-yl)-2-phenyl-1H-indole (17). Metabolic studies with this compound identified oxidation at the 6-position of the indole as a major route in vitro and in vivo in rats. Blocking this position with a fluorine atom led to 6-fluoro-3-(4-fluoropiperidin-3-yl)-2-phenyl-1H-indole (22), an antagonist with 0.06 nM affinity for h5-HT(2A) receptors, with bioavailability of 80% and half-life of 12 h in rats.

3-(4-Piperidinyl)- and 3-(8-aza-bicyclo[3.2.1]oct-3-yl)-2-phenyl-1H-indoles as bioavailable h5-HT2A antagonists

A series of 3-(4-piperidinyl)- and 3-(8-aza-bicyclo[3.2.1]oct-3-yl)-2-phenyl-1H-indoles have been prepared and evaluated as ligands for the h5-HT2A receptor. 3-(8-Phenethyl-8-aza-bicyclo[3.2.1]oct-3-yl)-2-phenyl-1H-indole is a high-affinity (1.2nM), selective (>800 fold over h5-HT2C and hD2 receptors) antagonist at the h5-HT2A receptor with oral bioavailability in rats.

Heterogeneity in therapeutic response of genetically altered myeloma cell lines to interleukin 6, dexamethasone, doxorubicin, and melphalan

Because there is no known genetic abnormality common to all patients with myeloma, it is important to understand how genetic heterogeneity may lead to differences in signal transduction, cell cycle, and response to therapy. Model cell lines have been used to study the effect that mutations in p53 and ras can have on growth properties and responses of myeloma cells. The U266 cell line has a single mutant p53 allele. Stable expression of wild-type (wt) p53 in U266 cells results in a significant suppression of interleukin (IL)-6 gene expression and in the concomitant suppression of cell growth that could be restored by the addition of exogenous IL-6. Expression of wt p53 also leads to cell cycle arrest and protection from doxorubicin (Dox)- and melphalan (Mel)-induced apoptosis. The addition of IL-6 resulted in cell cycle progression and blocked p53-mediated protection from apoptosis. ANBL6 is an IL-6-dependent cell line that is sensitive to dexamethasone (Dex), Dox, and Mel. IL-6 is able to protect ANBL6 cells from Dex- and Mel- but not Dox-induced apoptosis. To study the effect of an activating mutation in ras, the ANBL6 cell line transfected with either a constitutively activated N- or K-ras gene was used. Both N-ras12 and K-ras12 genes were able to protect ANBL6 cells from apoptosis induced by Dex, Dox, and Mel. These data show that changes in ras or p53 can alter the myeloma cell response to IL-6 and demonstrate that the genetic background can alter therapeutic responses.

N-(indol-3-ylglyoxylyl)piperidines: high affinity agonists of human GABA-A receptors containing the alpha1 subunit

A new class of N-(indol-3-ylglyoxylyl)piperidines are high affinity agonists at the benzodiazepine binding site of human GABA-A receptor ion-channels, with modest selectivity for receptors containing the alpha1 subunit over alpha2 and alpha3. All three receptor subtypes discriminate substantially between the two enantiomers of the chiral ligand 10.

Fluorination of 3-(3-(piperidin-1-yl)propyl)indoles and 3-(3-(piperazin-1-yl)propyl)indoles gives selective human 5-HT1D receptor ligands with improved pharmacokinetic profiles

It has previously been reported that a 3-(3-(piperazin-1-yl)propyl)indole series of 5-HT1D receptor ligands have pharmacokinetic advantages over the corresponding 3-(3-(piperidin-1-yl)propyl)indole series and that the reduced pKa of the piperazines compared to the piperidines may be one possible explanation for these differences. To investigate this proposal we have developed versatile synthetic strategies for the incorporation of fluorine into these ligands, producing novel series of 4-fluoropiperidines, 3-fluoro-4-aminopiperidines, and both piperazine and piperidine derivatives with one or two fluorines in the propyl linker. Ligands were identified which maintained high affinity and selectivity for the 5-HT1D receptor and showed agonist efficacy in vitro. The incorporation of fluorine was found to significantly reduce the pKa of the compounds, and this reduction of basicity was shown to have a dramatic, beneficial influence on oral absorption, although the effect on oral bioavailability could not always be accurately predicted.

4-N-linked-heterocyclic piperidine derivatives with high affinity and selectivity for human dopamine D4 receptors

The syntheses of a number of different N-linked heterocyclic pyrazole replacements based on the structure 1 are described (compounds 3-12) as hD4 ligands. After further optimisation the best compound identified was 13 which has high affinity for hD4 (5.2 nM) and >300-fold selectivity for hD4 receptors over hD2 and hD3 receptors.

Crucial points at diagnosis. Type 2 diabetes or slow type 1 diabetes

Two major types of diabetes have been recognized since the late 1930s. However, in recent times there have been major changes in classification and understanding of these types, including improved knowledge of maturity-onset diabetes in the young, with the identification of mutations relating to impaired insulin secretion and the recognition of slow-onset type 1 diabetes in adults now designated as latent autoimmune diabetes in adults (LADA). A major problem area in diabetes classification concerns cases of slowly progressive forms of type 1 and type 2 diabetes, particularly in adults aged 25-50 years. This is a more contemporary problem because cases of type 2 diabetes are presenting at an increasingly younger age. In the landmark U.K. Prospective Diabetes Study of type 2 diabetes, islet cell antibodies (ICAs) and antibodies to glutamic acid decarboxylase (anti-GAD) were measured at diagnosis in 3,672 patients. The overall proportion with ICAs was 6%, and anti-GADs was 10%. These subjects clearly had type 1 diabetes or LADA by both phenotypic and genotypic features. The presence of auto antibodies correlated particularly with a younger age and phenotypic features consistent with type 1 diabetes (e.g., early age at diagnosis, lower BMI, and reduced beta-cell function). Overall, of patients requiring insulin by 6 years, 38% were anti-GAD+ at baseline compared with 5.3% of those not on insulin at 6 years. Antibodies to GAD indicate an underlying autoimmune process and have a high positive predictive value for type 1 diabetes and future insulin dependency in adults.

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.

Type 1 diabetes in insulin-treated adult-onset diabetic subjects

The frequency of autoimmune features was compared in adult-onset diabetic subjects either requiring insulin treatment within 12 months of diagnosis or progressing to insulin therapy after a latency of at least 5 years. Adult-onset insulin-treated diabetic subjects were sampled from the population-based Canterbury Diabetes Registry (n = 1580). There were 237 (15%) registrants who met the study criteria of age < 75 years at 1 January 1993, age at diagnosis of diabetes > or = 45 years and duration of diabetes between 5 and 15 years; 101 subjects commenced insulin 5-15 years after diagnosis (group 1) and 80 subjects commenced insulin within 1 year of diagnosis (group 2). C-peptide levels, islet cell antibodies (ICA) and antibodies against glutamic acid decarboxylase (anti-GAD) were determined in all individuals from group 1 (n = 27) and group 2 (n = 23) who agreed to be recruited to the study. The group 1 and group 2 samples did not differ significantly in their demographic characteristics, nor were they different from the two groups from which they were drawn (mean age, 64.2 years; age at diagnosis, 53.5 years; duration of diabetes, 10.7 years; body mass index, 28.6 kg/m2). Overall, 12 of the 50 (24%) study subjects tested positive for anti-GAD; 43% (10) of group 2 subjects were anti-GAD positive compared with only 7.4% (2) of group 1 subjects (P < 0.01). Postprandial C-peptide levels were significantly lower in group 2 subjects compared with group 1 subjects (627 vs 1124 pM, P < 0.05). All subjects were ICA negative. These observations suggest that autoimmune destruction of beta-cells explains early requirement for insulin in adult-onset diabetes.

3-(1-piperazinyl)-4,5-dihydro-1H-benzo[g]indazoles: high affinity ligands for the human dopamine D4 receptor with improved selectivity over ion channels

3-(4-Piperidinyl)-5-arylpyrazoles, such as 1, were selective for the cloned human dopamine D4 receptor (hD4), but also showed affinity at voltage sensitive calcium, sodium and potassium ion channels. A combination of substituent changes to reduce the basicity of the piperidine nitrogen and conformational restriction to give 4,5-dihydro-1H-benzo[g]indazoles reduced this ion channel affinity at the expense of selectivity for hD4 over other dopamine receptors. Incorporation of piperazine into the 4,5-dihydro-1H-benzo[g]indazoles in place of piperidine gave a novel series of high affinity, selective, orally bioavailable hD4 ligands, such as 16, with improved selectivity over ion channels.

Effect of plasma protein binding on in vivo activity and brain penetration of glycine/NMDA receptor antagonists

A major issue in designing drugs as antagonists at the glycine site of the NMDA receptor has been to achieve good in vivo activity. A series of 4-hydroxyquinolone glycine antagonists was found to be active in the DBA/2 mouse anticonvulsant assay, but improvements in in vitro affinity were not mirrored by corresponding increases in anticonvulsant activity. Here we show that binding of the compounds to plasma protein limits their brain penetration. Relative binding to the major plasma protein, albumin, was measured in two different ways: by a radioligand binding experiment or using an HPLC assay, for a wide structural range of glycine/NMDA site ligands. These measures of plasma protein binding correlate well (r = 0.84), and the HPLC assay has been used extensively to quantify plasma protein binding. For the 4-hydroxyquinolone series, binding to plasma protein correlates (r = 0.92) with log P (octanol/pH 7.4 buffer) over a range of log P values from 0 to 5. The anticonvulsant activity increases with in vitro affinity, but the slope of a plot of pED50 versus pIC50 is low (0.40); taking plasma protein binding into account in this plot increases the slope to 0.60. This shows that binding to albumin in plasma reduces the amount of compound free to diffuse across the blood-brain barrier. Further evidence comes from three other experiments: (a) Direct measurements of brain/blood ratios for three compounds (2, 16, 26) show the ratio decreases with increasing log R. (b) Warfarin, which competes for albumin binding sites dose-dependently, decreased the ED50 of 26 for protection against seizures induced by NMDLA. (c) Direct measurements of brain penetration using an in situ brain perfusion model in rat to measure the amount of drug crossing the blood-brain barrier showed that compounds 2, 26, and 32 penetrate the brain well in the absence of plasma protein, but this is greatly reduced when the drug is delivered in plasma. In the 4-hydroxyquinolones glycine site binding affinity increases with lipophilicity of the 3-substituent up to a maximum at a log P around 3, then does not improve further. When combined with increasing protein binding, this gives a parabolic relationship between predicted in vivo activity and log P, with a maximum log P value of 2.39. Finally, the plasma protein binding studies have been extended to other series of glycine site antagonists, and its is shown that for a given log P these have similar protein binding to the 4-hydroxyquinolones, except for compounds that are not acidic. The results have implications for the design of novel glycine site antagonists, and it is suggested that it is necessary to either keep log P low or pKa high to obtain good central nervous system activity.

4-Heterocyclylpiperidines as selective high-affinity ligands at the human dopamine D4 receptor

5-(4-Chlorophenyl)-3-(1-(4-chlorobenzyl)piperidin-4-yl)pyrazole (3) was identified from screening of the Merck sample collection as a human dopamine D4 (hD4) receptor ligand with moderate affinity (61 nM) and 4-fold selectivity over human D2 (hD2) receptors. Four separate parts of the molecule have been examined systematically to explore structure-activity relationships with respect to hD4 affinity and selectivity over other dopamine receptors. It was found that the 4-chlorophenyl group attached to the pyrazole is optimal, as is the 4-substituted piperidine. The lipophilic group on the basic nitrogen is more amenable to change, with the optimal group found to be a phenethyl. The aromatic heterocyle can be altered to a number of different groups, with isoxazoles and pyrimidines showing improved affinities. This heterocycle can also be advantageously alkylated, improving the selectivity of the compounds over D2 receptors. It is hypothesized that the conformation around the bond joining the aromatic heterocycle to the piperidine is important for D4 affinity, based on crystal structures of isoxazoles (29 and 30) and on a conformationally constrained compound (28). Putting all the favorable changes together led to the discovery that 5-(4-chlorophenyl)-4-methyl-3-(1-(2-phenylethyl)piperidin-4-yl)iso xazole (36) is a nanomolar antagonist at human dopamine D4 receptors with > 500-fold selectivity over hD2 and > 200-fold selectivity over hD3. Compound 36 is an antagonist of hD4 receptors with good oral bioavailability of 38%, a half life of 2 h, and brain levels 10-fold higher than plasma levels.