GDE6 promotes progenitor identity in the vertebrate neural tube.

The generation of neurons in the central nervous system is a complex, stepwise process necessitating the coordinated activity of mitotic progenitors known as radial glia. Following neural tube closure, radial glia undergo a period of active proliferation to rapidly expand their population, creating a densely packed neurepithelium. Simultaneously, radial glia positioned across the neural tube are uniquely specified to produce diverse neuronal sub-types. Although these cellular dynamics are well studied, the molecular mechanisms governing them are poorly understood. The six-transmembrane Glycerophosphodiester Phosphodiesterase proteins (GDE2, GDE3, and GDE6) comprise a family of cell-surface enzymes expressed in the embryonic nervous system. GDE proteins can release Glycosylphosphatidylinositol-anchored proteins from the cell surface via cleavage of their lipid anchor. GDE2 has established roles in motor neuron differentiation and oligodendrocyte maturation, and GDE3 regulates oligodendrocyte precursor cell proliferation. Here, we describe a role for GDE6 in early neural tube development. Using RNAscope, we show that Gde6 mRNA is expressed by ventricular zone progenitors in the caudal neural tube. Utilizing in-ovo electroporation, we show that GDE6 overexpression promotes neural tube hyperplasia and ectopic growths of the neurepithelium. At later stages, electroporated embryos exhibit an expansion of the ventral patterning domains accompanied by reduced cross-repression. Ultimately, electroporated embryos fail to produce the full complement of post-mitotic motor neurons. Our findings indicate that GDE6 overexpression significantly affects radial glia function and positions GDE6 as a complementary factor to GDE2 during neurogenesis.

A direct-drive GFP reporter for studies of tracheal development in Drosophila.

The Drosophila tracheal system consists of a widespread tubular network that provides respiratory functions for the animal. Its development, from ten pairs of placodes in the embryo to the final stereotypical branched structure in the adult, has been extensively studied by many labs as a model system for understanding tubular epithelial morphogenesis. Throughout these studies, a breathless (btl)-GAL4 driver has provided an invaluable tool to either mark tracheal cells during development or to manipulate gene expression in this tissue. A distinct shortcoming of this approach, however, is that btl-GAL4 cannot be used to specifically visualize tracheal cells in the presence of other GAL4 drivers or other UAS constructs, restricting its utility. Here we describe a direct-drive btl-nGFP reporter that can be used as a specific marker of tracheal cells throughout development in combination with any GAL4 driver and/or UAS construct. This reporter line should facilitate the use of Drosophila as a model system for studies of tracheal development and tubular morphogenesis.

Multiomic identification of factors associated with progression to cystic kidney disease in mice with nephron Ift88 disruption.

Ift88 gene mutations cause primary cilia loss and polycystic kidney disease (PKD) in mice. Nephron intraflagellar transport protein 88 (Ift88) knockout (KO) at 2 mo postnatal does not affect renal histology at 4 mo postnatal and causes PKD only in males by 11 mo postnatal. To identify factors associated with PKD development, kidneys from 4-mo-old male and female control and Ift88 KO mice underwent transcriptomic, proteomic, Western blot, metabolomic, and lipidomic analyses. mRNAs involved in extracellular matrix (ECM) synthesis and degradation were selectively upregulated in male KO mice. Proteomic analysis was insufficiently sensitive to detect most ECM components, while Western blot analysis paradoxically revealed reduced fibronectin and collagen type I in male KO mice. Only male KO mice had upregulated mRNAs encoding fibrinogen subunits and receptors for vascular endothelial growth factor and platelet-derived growth factor; period 2, period 3, and nuclear receptor subfamily 1 group D member 1 clock mRNAs were selectively decreased in male KO mice. Proteomic, metabolomic, and lipidomic analyses detected a relative (vs. the same-sex control) decrease in factors involved in fatty acid ß-oxidation in female KO mice, while increased or unchanged levels in male KO mice, including medium-chain acyl-CoA dehydrogenase, 3-hydroxybutyrate, and acylcarnitine. Three putative mRNA biomarkers of cystogenesis in male Ift88 KO mice (similar control levels between sexes and uniquely altered by KO in males) were identified, including high levels (fibrinogen α-chain and stromal cell-derived factor 2-like 1) and low levels (BTG3-associated nuclear protein) in male KO mice. These findings suggest that relative alterations in renal ECM metabolism, fatty acid ß-oxidation, and other pathways precede cystogenesis in Ift88 KO mice. In addition, potential novel biomarkers of cystogenesis in Ift88 KO mice have been identified.NEW & NOTEWORTHY Male, but not female, mice with nephron intraflagellar transport protein 88 (Ift88) gene knockout (KO) develop polycystic kidneys by ∼1 yr postnatal. We performed multiomic analysis of precystic male and female Ift88 KO and control kidneys. Precystic male Ift88 KO mice exhibited differential alterations (vs. females) in mRNA, proteins, metabolites, and/or lipids associated with renal extracellular matrix metabolism, fatty acid ß-oxidation, circadian rhythm, and other pathways. These findings suggest targets for evaluation in the pathogenesis of Ift88 KO polycystic kidneys.

Drosophila estrogen-related receptor directs a transcriptional switch that supports adult glycolysis and lipogenesis.

Metabolism and development must be closely coupled to meet the changing physiological needs of each stage in the life cycle. The molecular mechanisms that link these pathways, however, remain poorly understood. Here we show that the Drosophila estrogen-related receptor (dERR) directs a transcriptional switch in mid-pupae that promotes glucose oxidation and lipogenesis in young adults. dERR mutant adults are viable but display reduced locomotor activity, susceptibility to starvation, elevated glucose, and an almost complete lack of stored triglycerides. Molecular profiling by RNA-seq, ChIP-seq, and metabolomics revealed that glycolytic and pentose phosphate pathway genes are induced by dERR, and their reduced expression in mutants is accompanied by elevated glycolytic intermediates, reduced TCA cycle intermediates, and reduced levels of long chain fatty acids. Unexpectedly, we found that the central pathways of energy metabolism, including glycolysis, the tricarboxylic acid cycle, and electron transport chain, are coordinately induced at the transcriptional level in mid-pupae and maintained into adulthood, and this response is partially dependent on dERR, leading to the metabolic defects observed in mutants. Our data support the model that dERR contributes to a transcriptional switch during pupal development that establishes the metabolic state of the adult fly.

For Intestinal Homeostasis, You Are What You Eat.

Nutrients play a central role in controlling the form and function of the intestinal epithelium. In this issue of Developmental Cell, Mattila et al. (2018) and Obniski et al. (2018) uncover important mechanisms by which Drosophila intestinal stem cells respond to dietary signals, linking nutrients to tissue homeostasis.

Effect of Buprenorphine Implants on Illicit Opioid Use Among Abstinent Adults With Opioid Dependence Treated With Sublingual Buprenorphine: A Randomized Clinical Trial.

IMPORTANCE: The effectiveness of buprenorphine treatment of opioid dependence is limited by suboptimal medication adherence, abuse, and diversion. OBJECTIVE: To determine whether 6-month buprenorphine implants are noninferior to daily sublingual buprenorphine as maintenance treatment for opioid-dependent patients with stable abstinence. DESIGN, SETTING, AND PARTICIPANTS: Outpatient, randomized, active-controlled, 24-week, double-blind, double-dummy study conducted at 21 US sites from June 26, 2014, through May 18, 2015. Outpatients were prescribed daily sublingual buprenorphine for 6 months or more, were abstinent while taking 8 mg/d or less of sublingual buprenorphine for 90 days or longer, and were determined to be clinically stable by their physician. INTERVENTIONS: Participants were randomized to receive sublingual buprenorphine plus 4 placebo implants or sublingual placebo plus four 80-mg buprenorphine hydrochloride implants (expected efficacy, 24 weeks). MAIN OUTCOME MEASURE: The primary end point was between-group difference in proportion of responders (≥4 of 6 months without opioid-positive urine test result [monthly and 4 times randomly] and self-report). The noninferiority established for the lower bound of the 95% confidence interval was greater than -0.20 (P < .025). Secondary end points included cumulative percentage of negative opioid urine results, abstinence, and time to first illicit opioid use. Safety was assessed by adverse event reporting. RESULTS: Of 177 participants (mean age, 39 years; 40.9% female), 90 were randomized to sublingual buprenorphine with placebo implants and 87 to buprenorphine implants with sublingual placebo; 165 of 177 (93.2%) completed the trial. Eighty-one of 84 (96.4%) receiving buprenorphine implants and 78 of 89 (87.6%) receiving sublingual buprenorphine were responders, an 8.8% difference (1-sided 97.5% CI, 0.009 to ∞; P < .001 for noninferiority). Over 6 months, 72 of 84 (85.7%) receiving buprenorphine implants and 64 of 89 (71.9%) receiving sublingual buprenorphine maintained opioid abstinence (hazard ratio, 13.8; 95% CI, 0.018-0.258; P = .03). Non-implant-related and implant-related adverse events occurred in 48.3% and 23% of the buprenorphine implant group and in 52.8% and 13.5% of participants in the sublingual buprenorphine group, respectively. CONCLUSIONS AND RELEVANCE: Among adults with opioid dependence maintaining abstinence with a stable dose of sublingual buprenorphine, the use of buprenorphine implants compared with continued sublingual buprenorphine did not result in an inferior likelihood of remaining a responder. However, the study population had an exceptionally high response rate in the control group, and further studies are needed in broader populations to assess the efficacy in other settings. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT02180659.

The Drosophila Prosecretory Transcription Factor dimmed Is Dynamically Regulated in Adult Enteroendocrine Cells and Protects Against Gram-Negative Infection.

The endocrine system employs peptide hormone signals to translate environmental changes into physiological responses. The diffuse endocrine system embedded in the gastrointestinal barrier epithelium is one of the largest and most diverse endocrine tissues. Furthermore, it is the only endocrine tissue in direct physical contact with the microbial environment of the gut lumen. However, it remains unclear how this sensory epithelium responds to specific pathogenic challenges in a dynamic and regulated manner. We demonstrate that the enteroendocrine cells of the adult Drosophila melanogaster midgut display a transient, sensitive, and systemic induction of the prosecretory factor dimmed (dimm) in response to the Gram-negative pathogen Pseudomonas entomophila (Pe). In enteroendocrine cells, dimm controls the levels of the targets Phm, dcat-4, and the peptide hormone, Allatostatin A. Finally, we identify dimm as a host factor that protects against Pe infection and controls the expression of antimicrobial peptides. We propose that dimm provides "gain" in enteroendocrine output during the adaptive response to episodic pathogen exposure.

Buprenorphine implants for treatment of opioid dependence: randomized comparison to placebo and sublingual buprenorphine/naloxone.

AIMS: To evaluate the safety and efficacy of buprenorphine implants (BI) versus placebo implants (PI) for the treatment of opioid dependence. A secondary aim compared BI to open-label sublingual buprenorphine/naloxone tablets (BNX). DESIGN: Randomized, double-blind, placebo-controlled trial. Subjects received either four buprenorphine implants (80 mg/implant) (n = 114), four placebo implants (n = 54) or open-label BNX (12-16 mg/day) (n = 119). SETTING: Twenty addiction treatment centers. PARTICIPANTS: Adult out-patients (ages 18-65) with DSM-IV-TR opioid dependence. MEASUREMENTS: The primary efficacy end-point was the percentage of urine samples negative for opioids collected from weeks 1 to 24, examined as a cumulative distribution function (CDF). FINDINGS: The BI CDF was significantly different from placebo (P < 0.0001). Mean [95% confidence interval (CI)] proportions of urines negative for opioids were: BI = 31.2% (25.3, 37.1) and PI = 13.4% (8.3, 18.6). BI subjects had a higher study completion rate relative to placebo (64 versus 26%, P < 0.0001), lower clinician-rated (P < 0.0001) and patient-rated (P < 0.0001) withdrawal, lower patient-ratings of craving (P < 0.0001) and better subjects' (P = 0.031) and clinicians' (P = 0.022) global ratings of improvement. BI also resulted in significantly lower cocaine use (P = 0.0016). Minor implant-site reactions were comparable in the buprenorphine [27.2% (31 of 114)] and placebo groups [25.9% (14 of 54)]. BI were non-inferior to BNX on percentage of urines negative for opioids [mean (95% CI) = 33.5 (27.3, 39.6); 95% CI for the difference of proportions = (-10.7, 6.2)]. CONCLUSIONS: Compared with placebo, buprenorphine implants result in significantly less frequent opioid use and are non-inferior to sublingual buprenorphine/naloxone tablets.

Intrastriatal transplantation of microcarrier-bound human retinal pigment epithelial cells versus sham surgery in patients with advanced Parkinson's disease: a double-blind, randomised, controlled trial.

BACKGROUND: Human retinal pigment epithelial (RPE) cells produce levodopa and their transplantation into the striatum might improve continuity of administration compared with that achieved with oral levodopa. We aimed to assess the safety, tolerability, and efficacy of transplantation of microcarrier-bound human RPE cells versus a sham surgery control in patients with advanced Parkinson's disease. METHODS: In this randomised, double-blind study eligible patients were aged 36-70 years, had been symptomatic for at least 5 years, were in Hoehn and Yahr stage 3-4 and had unified Parkinson's disease rating scale (UPDRS) motor scores of 38-70 when off medication (off state), and had symptoms that responded to oral levodopa but were insufficiently controlled by optimised pharmacotherapy. Randomisation was done in a 1:1 ratio. Only the neurosurgical team was aware of treatment assignments. During stereotactic transplantation around 325,000 cells per side were injected into the postcommissural putamen; sham surgery patients received partial burr holes. The primary efficacy endpoint was change in UPDRS off-state motor score at 12 months. This study is registered with ClinicalTrials.gov, number NCT00206687. FINDINGS: Of 71 enrolled patients, 35 underwent cell transplantation and 36 sham surgery. Change in mean motor scores did not differ significantly between groups (-10.5 [SD 10.26] for transplantation vs -10.1 [SD 12.26] for sham surgery, p=0.9). The overall rate of adverse events was similar in the two study groups, although the number attributable to surgery or RPE cells (mostly neurological or psychiatric) was higher in transplant recipients. Two and seven patients died in the sham surgery and transplantation group, respectively; one death in the latter group was possibly related to surgery or RPE cells. INTERPRETATION: Transplantation of human RPE cells provided no antiparkinsonian benefits compared with sham surgery. FUNDING: Bayer HealthCare AG.

Plastic endocrine regulation of year-round territorial aggression in tropical male spotted antbirds.

Studies investigating the hormonal regulation of aggression often focus on the role of the steroid hormone testosterone (T). These studies have generally found an association in temperate zone species between T and male aggression in a reproductive context. However, in most temperate zone species seasonal variation in reproductive context cannot easily be separated from concomitant seasonal changes in other variables, including territory location and partner presence. Therefore, we investigated the hormonal regulation of territorial aggression in a tropical bird that breeds seasonally, but remains mated and territorial year-round. Free-living male spotted antbirds (Hylophylax n. naevioides) displayed similar aggressive behavior in the non-breeding, early, and middle breeding seasons when exposed to a simulated territorial intrusion (STI). Plasma T concentrations after STIs were low and seasonally invariant, but plasma dehydroepiandrosterone (DHEA) was elevated during the non-breeding season. Simultaneous administration of pharmacological inhibitors of androgenic and estrogenic actions during the non-breeding season was less effective in reducing aggressive behavior of captive males compared with a previous study conducted during the breeding season. Hence, in male spotted antbirds endocrine mechanisms appear to vary with reproductive context, both in DHEA concentrations and in the importance of T for regulating aggressive behavior. Furthermore, combining the current data with previous findings suggests that short-term increases in T during aggressive interactions in this tropical species are dependent on the context and the intensity of aggressive stimuli, regardless of season.

Buprenorphine implants for treatment of opioid dependence: a randomized controlled trial.

CONTEXT: Limitations of existing pharmacological treatments for opioid dependence include low adherence, medication diversion, and emergence of withdrawal symptoms. OBJECTIVE: To determine the efficacy of buprenorphine implants that provide a low, steady level of buprenorphine over 6 months for the treatment of opioid dependence. DESIGN, SETTING, AND PARTICIPANTS: A randomized, placebo-controlled, 6-month trial conducted at 18 sites in the United States between April 2007 and June 2008. One hundred sixty-three adults, aged 18 to 65 years, diagnosed with opioid dependence. One hundred eight were randomized to receive buprenorphine implants and 55 to receive placebo implants. INTERVENTION: After induction with sublingual buprenorphine-naloxone tablets, patients received either 4 buprenorphine implants (80 mg per implant) or 4 placebo implants. A fifth implant was available if a threshold for rescue use of sublingual buprenorphine-naloxone treatment was exceeded. Standardized individual drug counseling was provided to all patients. MAIN OUTCOME MEASURE: The percentage of urine samples negative for illicit opioids for weeks 1 through 16 and for weeks 17 through 24. RESULTS: The buprenorphine implant group had significantly more urine samples negative for illicit opioids during weeks 1 through 16 (P = .04). Patients with buprenorphine implants had a mean percentage of urine samples that tested negative for illicit opioids across weeks 1 through 16 of 40.4% (95% confidence interval [CI], 34.2%-46.7%) and a median of 40.7%; whereas those in the placebo group had a mean of 28.3% (95% CI, 20.3%-36.3%) and a median of 20.8%. A total of 71 of 108 patients (65.7%) who received buprenorphine implants completed the study vs 17 of 55 (30.9%) who received placebo implants (P < .001). Those who received buprenorphine implants also had fewer clinician-rated (P <.001) and patient-rated (P = .004) withdrawal symptoms, had lower patient ratings of craving (P <.001), and experienced a greater change on clinician global ratings of severity of opioid dependence (P<.001) and on the clinician global ratings of improvement (P < .001) than those who received placebo implants. Minor implant site reactions were the most common adverse events: 61 patients (56.5%) in the buprenorphine group and 29 (52.7%) in the placebo group. CONCLUSION: Among persons with opioid dependence, the use of buprenorphine implants compared with placebo resulted in less opioid use over 16 weeks as assessed by urine samples. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00447564.

JAK/STAT signaling coordinates stem cell proliferation and multilineage differentiation in the Drosophila intestinal stem cell lineage.

Adult stem cells are the most primitive cells of a lineage and are distinguished by the properties of self-renewal and multipotency. Coordinated control of stem cell proliferation and multilineage differentiation is essential to ensure a steady output of differentiated daughter cells necessary to maintain tissue homeostasis. However, little is known about the signals that coordinate stem cell proliferation and daughter cell differentiation. Here we investigate the role of the conserved JAK/STAT signaling pathway in the Drosophila intestinal stem cell (ISC) lineage. We show first, that JAK/STAT signaling is normally active in both ISCs and their newly formed daughters, but not in terminally differentiated enteroendocrine (ee) cells or enterocyte (EC) cells. Second, analysis of ISC lineages shows that JAK/STAT signaling is necessary but not sufficient for daughter cell differentiation, indicating that competence to undergo multilineage differentiation depends upon JAK/STAT. Finally, our analysis reveals JAK/STAT signaling to be a potent regulator of ISC proliferation, but not ISC self-renewal. On the basis of these findings, we suggest a model in which JAK/STAT signaling coordinates the processes of stem cell proliferation with the competence of daughter cells to undergo multilineage differentiation, ensuring a robust cellular output in the lineage.

Adenomatous polyposis coli regulates Drosophila intestinal stem cell proliferation.

Adult stem cells define a cellular reserve with the unique capacity to replenish differentiated cells of a tissue throughout an organism's lifetime. Previous analysis has demonstrated that the adult Drosophila midgut is maintained by a population of multipotent intestinal stem cells (ISCs) that resides in epithelial niches. Adenomatous polyposis coli (Apc), a tumor suppressor gene conserved in both invertebrates and vertebrates, is known to play a role in multiple developmental processes in Drosophila. Here, we examine the consequences of eliminating Apc function on adult midgut homeostasis. Our analysis shows that loss of Apc results in the disruption of midgut homeostasis and is associated with hyperplasia and multilayering of the midgut epithelium. A mosaic analysis of marked ISC cell lineages demonstrates that Apc is required specifically in ISCs to regulate proliferation, but is not required for ISC self-renewal or the specification of cell fate within the lineage. Cell autonomous activation of Wnt signaling in the ISC lineage phenocopied Apc loss and Apc mutants were suppressed in an allele-specific manner by abrogating Wnt signaling, suggesting that the effects of Apc are mediated in part by the Wnt pathway. Together, these data underscore the essential requirement of Apc in exerting regulatory control over stem cell activity, as well as the consequences that disrupting this regulation can have on tissue homeostasis.

Open-label dose-finding trial of buprenorphine implants (Probuphine) for treatment of heroin dependence.

Buprenorphine, a mu-opioid receptor partial agonist, has been shown to be safe and effective for treatment of opioid dependence. A novel implantable formulation of buprenorphine (Probuphine), using a polymer matrix sustained-release technology, has been developed to offer treatment for opioid dependence while minimizing risks of patient noncompliance and illicit diversion. The goal of the current study was to conduct an initial, open-label, evaluation of the safety, pharmacokinetics, and efficacy of two doses of Probuphine in subjects with opioid dependence maintained on sublingual buprenorphine. Two doses of Probuphine were evaluated in 12 heroin-dependent volunteers switched from daily sublingual buprenorphine dosing to either two or four Probuphine implants based upon their buprenorphine daily maintenance dose of 8 mg or 16 mg respectively, and were monitored for 6 months. Probuphine implants provided continuous steady state delivery of buprenorphine until their removal at 6 months. Withdrawal symptoms and craving remained low throughout the 6 months. For the 12 subjects, an average of 59% of urines were opioid-negative across the 6 month treatment period. Injection site reactions were present in half of patients, but none were serious. No safety concerns were evident. These results suggest that Probuphine implants offer significant promise for enhancing delivery of effective opioid substitution treatment while minimizing risk for abuse of medication.

Hematopoietic stem cell engraftment: a direct comparison between intramarrow and intravenous injection in nonhuman primates.

OBJECTIVE: Recent studies in the mouse model have shown improved engraftment of repopulating cells when cells were administered by intramarrow (IM) vs intravenous (IV) injection. Here we wished to determine if IM injection was feasible and would result in improved engraftment in a clinically relevant large animal model. MATERIALS AND METHODS: We used a competitive repopulation assay to directly compare IM vs IV injection in four baboons. CD34+ autologous bone marrow cells were split into two equal fractions and transduced with either green fluorescent protein (GFP) or yellow fluorescent protein (YFP). Gene-marked cells were infused by IM or IV administration after myeloablative irradiation. RESULTS: Peripheral blood granulocyte marking peaked at 2 to 3 weeks after transplantation and decreased thereafter before stabilizing. In all animals, marking levels of IM-injected cells (GFP) were lower than those of IV-injected cells (YFP) early after transplantation. However, in two of the four monkeys, GFP marking steadily increased after 2 months resulting in higher marking levels from IM-injected cells. In one animal, this trend sustained up to the last follow-up at 1 year after transplantation, with marking levels of 63.4% and 9.7% from IM- and IV-injected cells, respectively. Transplantation of both IM- and IV-injected CD34+ cells resulted in polyclonal multilineage engraftment. CONCLUSION: Our data show efficient gene marking after IM injection and suggest a different engraftment profile for IM- vs IV-injected repopulating cells.

A randomized, controlled, trial of controlled release paroxetine in fibromyalgia.

PURPOSE: We investigated the efficacy and tolerability of paroxetine controlled release, a selective serotonin reuptake inhibitor in fibromyalgia. METHODS: After excluding patients with current major depression and anxiety disorders, 116 subjects with fibromyalgia were enrolled in a 12-week, randomized, double-blind, placebo-controlled, trial of paroxetine controlled release (12.5-62.5 mg/day). The primary outcome measure was proportion of responders as defined as a> or =25% reduction in scores on the Fibromyalgia Impact Questionnaire (FIQ) from randomization to end of treatment. Secondary outcome measures included changes in FIQ scores, Clinical Global Impression -Improvement (CGI-I) and Severity (CGI-S) scores, Visual Analogue Scale for pain scores, number of tender points, and scores on the Sheehan Disability Scale (SDS). RESULTS: Significantly more patients in paroxetine controlled release group (57%) showed a> or =25% reduction in FIQ compared to placebo (33%) (P=.016). Paroxetine controlled release was significantly superior to placebo in reducing the FIQ total score (P =.015). The CGI-I ratings significantly favored the drug over placebo (P<.005). The improvements on other secondary outcome measures between the 2 groups were not statistically significant. Drowsiness, dry mouth, blurred vision, genital disorders, and anxiety were reported more frequently with paroxetine controlled release. The mean dose of paroxetine controlled release was 39.1 mg/day. CONCLUSIONS: Paroxetine controlled release appears to be well-tolerated and improve the overall symptomatology in patients with fibromyalgia without current mood or anxiety disorders. However, its effect on pain measures seems to be less robust.

A randomized controlled trial of paroxetine for noncardiac chest pain.

Noncardiac chest pain occurs frequently in medical practice and is often difficult to treat. We conducted a randomized double-blind, placebo-controlled, 8-week trial of paroxetine in 50 patients with noncardiac chest pain. None of the patients met criteria for panic disorder or major depression. Paroxetine-treated patients showed greater (P < .05) improvements than placebo-treated patients on the Clinical Global Impressions (CGI) scale. Both paroxetine and placebo-treated patients improved to a similar extent on selfrated pain measures, although baseline differences limited the interpretation of this outcome variable. There were no differences on other outcome ratings. Treatment was well tolerated. These preliminary findings extend other data on the potential of selective serotonin reuptake inhibitors for the acute treatment of noncardiac chest pain. Some recommendations for future studies to definitively test this potential are presented.

The efficacy of mifepristone in the reduction and prevention of olanzapine-induced weight gain in rats.

Atypical antipsychotics, such as olanzapine, have been associated with clinically significant weight gain. Changes to the hypothalamic pituitary adrenal axis may partially mediate this weight increase. Two experiments were conducted to test the effects of mifepristone on both mitigating and preventing olanzapine-induced weight gain. In the first experiment, adult female Sprague-Dawley rats gained significantly more weight on average when administered olanzapine for 35 days compared to vehicle controls. Subsequently, the olanzapine-treated rats were randomized to three dose levels of mifepristone (20, 60, and 200 mg/kg) in conjunction with olanzapine. Weight measurements were taken for 21 additional days. Rats receiving olanzapine plus mifepristone rapidly lost a significant portion of the weight gained during the olanzapine only phase (p = 0.0001). Rats in the 200 mg/kg dose group had significantly less abdominal fat compared to controls (p < 0.001) at study end. In the second experiment, daily mifepristone (20, 60, 200 mg/kg) initiated concomitantly with olanzapine was compared with olanzapine alone to determine if mifepristone prevented olanzapine-induced weight gain. After 21 days of treatment, mifepristone treated rats gained significantly less weight and had significantly less abdominal fat than rats administered olanzapine alone (p = 0.0002). Results suggest that mifepristone, a potent glucocorticoid antagonist, may both reduce and prevent olanzapine-induced weight gain in rats.

Differential effects of HOXB4 on nonhuman primate short- and long-term repopulating cells.

BACKGROUND: Hematopoietic stem cells (HSCs) or repopulating cells are able to self-renew and differentiate into cells of all hematopoietic lineages, and they can be enriched using the CD34 cell surface marker. Because of this unique property, HSCs have been used for HSC transplantation and gene therapy applications. However, the inability to expand HSCs has been a significant limitation for clinical applications. Here we examine, in a clinically relevant nonhuman primate model, the ability of HOXB4 to expand HSCs to potentially overcome this limitation. METHODS AND FINDINGS: Using a competitive repopulation assay, we directly compared in six animals engraftment of HOXB4GFP (HOXB4 green fluorescent protein) and control (yellow fluorescent protein [YFP])-transduced and expanded CD34+ cells. In three animals, cells were infused after a 3-d transduction culture, while in three other animals cells were infused after an additional 6-9 d of ex vivo expansion. We demonstrate that HOXB4 overexpression resulted in superior engraftment in all animals. The most dramatic effect of HOXB4 was observed early after transplantation, resulting in an up to 56-fold higher engraftment compared to the control cells. At 6 mo after transplantation, the proportion of marker gene-expressing cells in peripheral blood was still up to 5-fold higher for HOXB4GFP compared to YFP-transduced cells. CONCLUSIONS: These data demonstrate that HOXB4 overexpression in CD34+ cells has a dramatic effect on expansion and engraftment of short-term repopulating cells and a significant, but less pronounced, effect on long-term repopulating cells. These data should have important implications for the expansion and transplantation of HSCs, in particular for cord blood transplantations where often only suboptimal numbers of HSCs are available.

Lack of efficacy of the substance p (neurokinin1 receptor) antagonist aprepitant in the treatment of major depressive disorder.

BACKGROUND: An early clinical trial suggested that the substance P (neurokinin(1) receptor) antagonist, aprepitant, might provide a unique mechanism of antidepressant activity. Phase III trials were conducted to confirm these findings. METHODS: Five 8-week, randomized, double-blind, parallel-groups, placebo-controlled, multicenter trials in outpatients with Major Depressive Disorder were performed. Aprepitant 160 mg and placebo were included in all trials. Aprepitant 80 mg and paroxetine 20 mg (active comparator) were included in three trials. Approximately 150 patients were enrolled per treatment group in each trial. The primary end point was the mean change-from-baseline of the first 17 items of the Hamilton Rating Scale for Depression (HAM-D(17)) score at 8 weeks. A positron emission tomography (PET) study was also performed in normal subjects to determine the relationship between neurokinin(1) receptor occupancy and aprepitant plasma concentrations in dosing regimens relevant to the trials. RESULTS: No statistically significant differences from placebo on the HAM-D(17) were observed at week 8 for either dose of aprepitant in any of the trials, whereas paroxetine 20 mg was significantly (p