Protocol of trans-Tasman feasibility randomised controlled trial of the Younger Women's Wellness After Breast Cancer (YWWACP) lifestyle intervention

BACKGROUND

Younger women (defined as those < 50 years who are likely pre-menopausal at time of diagnosis) with breast cancer often experience persistent treatment-related side effects that adversely affect their physical and psychological wellbeing. The Women's Wellness After Cancer Program (WWACP) was adapted and piloted in Australia to address these outcomes in younger women. The aims of this feasibility study are to determine (1) the potential to translate the Younger WWACP (YWWACP) intervention to a broader population base in Aotearoa/New Zealand and Australia, and (2) the potential for success of a larger, international, phase ΙΙΙ, randomised controlled trial.

METHODS

This bi-national, randomised, single-blinded controlled trial involves two main study sites in Aotearoa/New Zealand (Kōwhai study) and Australia (EMERALD study). Young women aged 18 to 50 years who completed intensive treatment (surgery, chemotherapy, and/or radiotherapy) for breast cancer in the previous 24 months are eligible. The potential to translate the YWWACP to women in these two populations will be assessed according to several feasibility outcomes. These include examining intervention accessibility, acceptability and uptake; intervention sustainability and adherence; the prevalence components of the intervention in the control group; intervention efficacy; participants' perception of measurement burden; the effectiveness of planned recruitment strategies; and trial methods and procedures. The studies collectively aim to enrol 60 participants in the intervention group and 60 participants in the control group (total = 120 participants).

DISCUSSION

Ethical approval has been received from the Southern Health and Disability Ethics Committee (Kōwhai ref: 19/STH/215), and UnitingCare Human Research Ethics Committee (EMERALD ref: 202103). This study will provide important data on the feasibility of the refined YWWACP in the trans-Tasman context. This study will account for and harmonise cross-country differences to ensure the success of a proposed international grant application for a phase ΙΙΙ randomised controlled trial of this program to improve outcomes in younger women living with breast cancer.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR): Kōwhai ACTRN12620000260921 , registered on 27 February 2020. EMERALD ACTRN12621000447853 , registered on 19 April 2021.

Liquid biopsy for cancer diagnosis using vibrational spectroscopy: systematic review

Background

Vibrational spectroscopy (VS) is a minimally invasive tool for analysing biological material to detect disease. This study aimed to review its application to human blood for cancer diagnosis.

Methods

A systematic review was undertaken using a keyword electronic database search (MEDLINE, Embase, PubMed, TRIP and Cochrane Library), with all original English‐language manuscripts examining the use of vibrational spectral analysis of human blood for cancer detection. Studies involving fewer than 75 patients in the cancer or control group, animal studies, or where the primary analyte was not blood were excluded.

Results

From 1446 results, six studies (published in 2010–2018) examining brain, bladder, oral, breast, oesophageal and hepatic cancer met the criteria for inclusion, with a total population of 2392 (1316 cancer, 1076 control; 1476 men, 916 women). For cancer detection, reported mean sensitivities in each included study ranged from 79·3 to 98 per cent, with specificities of 82·8–95 per cent and accuracies between 81·1 and 97·1 per cent. Heterogeneity in reporting strategies, methods and outcome measures made meta‐analysis inappropriate.

Conclusion

VS shows high potential for cancer diagnosis, but until there is agreement on uniform standard reporting methods and studies with adequate sample size for valid classification models have been performed, its value in clinical practice will remain uncertain.

Vaginal lactic acid elicits an anti-inflammatory response from human cervicovaginal epithelial cells and inhibits production of pro-inflammatory mediators associated with HIV acquisition

Inflammation in the female reproductive tract (FRT) is associated with increased HIV transmission. Lactobacillus spp. dominate the vaginal microbiota of many women and their presence is associated with reduced HIV acquisition. Here we demonstrate that lactic acid (LA), a major organic acid metabolite produced by lactobacilli, mediates anti-inflammatory effects on human cervicovaginal epithelial cells. Treatment of human vaginal and cervical epithelial cell lines with LA (pH 3.9) elicited significant increases in the production of the anti-inflammatory cytokine IL-1RA. When added simultaneously or prior to stimulation, LA inhibited the Toll-like receptor agonist-elicited production of inflammatory mediators IL-6, IL-8, TNFα, RANTES, and MIP3α from epithelial cell lines and prevented IL-6 and IL-8 production by seminal plasma. The anti-inflammatory effect of LA was mediated by the protonated form present at pH≤3.86 and was observed with both L- and D-isomers. A similar anti-inflammatory effect of LA was observed in primary cervicovaginal cells and in an organotypic epithelial tissue model. These findings identify a novel property of LA that acts directly on epithelial cells to inhibit FRT inflammation and highlights the potential use of LA-containing agents in the lower FRT as adjuncts to female-initiated strategies to reduce HIV acquisition.

Potent and selective small-molecule MCL-1 inhibitors demonstrate on-target cancer cell killing activity as single agents and in combination with ABT-263 (navitoclax)

The anti-apoptotic protein MCL-1 is a key regulator of cancer cell survival and a known resistance factor for small-molecule BCL-2 family inhibitors such as ABT-263 (navitoclax), making it an attractive therapeutic target. However, directly inhibiting this target requires the disruption of high-affinity protein-protein interactions, and therefore designing small molecules potent enough to inhibit MCL-1 in cells has proven extremely challenging. Here, we describe a series of indole-2-carboxylic acids, exemplified by the compound A-1210477, that bind to MCL-1 selectively and with sufficient affinity to disrupt MCL-1-BIM complexes in living cells. A-1210477 induces the hallmarks of intrinsic apoptosis and demonstrates single agent killing of multiple myeloma and non-small cell lung cancer cell lines demonstrated to be MCL-1 dependent by BH3 profiling or siRNA rescue experiments. As predicted, A-1210477 synergizes with the BCL-2/BCL-XL inhibitor navitoclax to kill a variety of cancer cell lines. This work represents the first description of small-molecule MCL-1 inhibitors with sufficient potency to induce clear on-target cellular activity. It also demonstrates the utility of these molecules as chemical tools for dissecting the basic biology of MCL-1 and the promise of small-molecule MCL-1 inhibitors as potential therapeutics for the treatment of cancer.

Inhibition of αvβ6 promotes acute renal allograft rejection in nonhuman primates

The integrin αvβ6 activates latent transforming growth factor-β (TGF-β) within the kidney and may be a target for the prevention of chronic allograft fibrosis after kidney transplantation. However, TGF-β also has known immunosuppressive properties that are exploited by calcineurin inhibitors (CNIs); thus, the net benefit of αvβ6 inhibition remains undetermined. To assess the acute impact of interference with αvβ6 on acute rejection, we tested a humanized αvβ6-specific monoclonal antibody (STX-100) in a randomized, double-blinded, placebo-controlled nonhuman primate renal transplantation study to evaluate whether αvβ6 blockade alters the risk of acute rejection during CNI-based immunosuppression. Rhesus monkeys underwent renal allotransplantation under standard CNI-based maintenance immunosuppression; 10 biopsy-confirmed rejection-free animals were randomized to receive weekly STX-100 or placebo. Animals treated with STX-100 experienced significantly decreased rejection-free survival compared to placebo animals (p = 0.049). Immunohistochemical analysis confirmed αvβ6 ligand presence, and αvβ6 staining intensity was lower in STX-100-treated animals (p = 0.055), indicating an apparent blockade effect of STX-100. LAP, LTBP-1 and TGF-β were all decreased in animals that rejected on STX-100 compared to those that rejected on standard immunosuppression alone, suggesting a relevant effect of αvβ6 blockade on local TGF-β. These data caution against the use of αvβ6 blockade to achieve TGF-β inhibition in kidney transplantation.

Belatacept and sirolimus prolong nonhuman primate renal allograft survival without a requirement for memory T cell depletion

Belatacept is an inhibitor of CD28/B7 costimulation that is clinically indicated as a calcineurin inhibitor (CNI) alternative in combination with mycophenolate mofetil and steroids after renal transplantation. We sought to develop a clinically translatable, nonlymphocyte depleting, belatacept-based regimen that could obviate the need for both CNIs and steroids. Thus, based on murine data showing synergy between costimulation blockade and mTOR inhibition, we studied rhesus monkeys undergoing MHC-mismatched renal allotransplants treated with belatacept and the mTOR inhibitor, sirolimus. To extend prior work on costimulation blockade-resistant rejection, some animals also received CD2 blockade with alefacept (LFA3-Ig). Belatacept and sirolimus therapy successfully prevented rejection in all animals. Tolerance was not induced, as animals rejected after withdrawal of therapy. The regimen did not deplete T cells. Alefecept did not add a survival benefit to the optimized belatacept and sirolimus regimen, despite causing an intended depletion of memory T cells, and caused a marked reduction in regulatory T cells. Furthermore, alefacept-treated animals had a significantly increased incidence of CMV reactivation, suggesting that this combination overly compromised protective immunity. These data support belatacept and sirolimus as a clinically translatable, nondepleting, CNI-free, steroid-sparing immunomodulatory regimen that promotes sustained rejection-free allograft survival after renal transplantation.

Direct visualization of Bcl-2 family protein interactions using live cell fluorescent protein redistribution assays

Bcl-2 family proteins have important roles in tumor initiation, progression and resistance to therapy. Pro-survival Bcl-2 proteins are regulated by their interactions with pro-death BH3-only proteins making these protein–protein interactions attractive therapeutic targets. Although these interactions have been extensively characterized biochemically, there is a paucity of tools to assess these interactions in cells. Here, we address this limitation by developing quantitative, high throughput microscopy assays to characterize Bcl-2 and BH3-only protein interactions in live cells. We use fluorescent proteins to label the interacting proteins of interest, enabling visualization and quantification of their mitochondria-localized interactions. Using tool compounds, we demonstrate the suitability of our assays to characterize the cellular activity of putative therapeutic molecules that target the interaction between pro-survival Bcl-2 and pro-death BH3-only proteins. In addition to the relevance of our assays for drug discovery, we anticipate that our work will contribute to an improved understanding of the mechanisms that regulate these important protein–protein interactions within the cell.

Comparison of hydrazone heterobifunctional cross-linking agents for reversible conjugation of thiol-containing chemistry

Reversible covalent conjugation chemistries that allow site- and condition-specific coupling and uncoupling reactions are attractive components in nanotechnologies, bioconjugation methods, imaging, and drug delivery systems. Here, we compare three heterobifunctional cross-linkers, containing both thiol- and amine-reactive chemistries, to form pH-labile hydrazones with hydrazide derivatives of the known and often published water-soluble polymer, poly[N-(2-hydroxypropyl methacrylamide)] (pHPMA), while subsequently coupling thiol-containing molecules to the cross-linker via maleimide addition. Two novel cross-linkers were prepared from the popular heterobifunctional cross-linking agent, succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC), modified to contain either terminal aldehyde groups (i.e., 1-(N-3-propanal)-4-(N-maleimidomethyl) cyclohexane carboxamide, PMCA) or methylketone groups (i.e., 1-(N-3-butanone)-4-(N-maleimidomethyl) cyclohexane carboxamide, BMCA). A third cross-linking agent was the commercially available N-4-acetylphenyl maleimide (APM). PMCA and BMCA exhibited excellent reactivity toward hydrazide-derivatized pHPMA with essentially complete hydrazone conjugation to polymer reactive sites, while APM coupled only ∼60% of available reactive sites on the polymer despite a 3-fold molar excess relative to polymer hydrazide groups. All polymer hydrazone conjugates bearing these bifunctional agents were then further reacted with thiol-modified tetramethylrhodamine dye, confirming cross-linker maleimide reactivity after initial hydrazone polymer conjugation. Incubation of dye-labeled polymer conjugates in phosphate buffered saline at 37 °C showed that hydrazone coupling resulting from APM exhibited the greatest difference in stability between pH 7.4 and 5.0, with hydrolysis and dye release increased at pH 5.0 over a 24 h incubation period. Polymer conjugates bearing hydrazones formed from cross-linker BMCA exhibited intermediate stability with hydrolysis much greater at pH 5.0 at early time points, but hydrolysis at pH 7.4 was significant after 5 h. Hydrazones formed with the PMCA cross-linker showed no difference in release rates at pH 7.4 and 5.0.

Spatial steering of deep brain stimulation volumes using a novel lead design

OBJECTIVE

To investigate steering the volume of activated tissue (VTA) with deep brain stimulation (DBS) using a novel high spatial-resolution lead design.

METHODS

We examined the effect of asymmetric current-injection across the DBS-array on the VTA. These predictions were then evaluated acutely in a non-human primate implanted with the DBS-array, using motor side-effect thresholds as the metric for estimating VTA asymmetries.

RESULTS

Simulations show the DBS-array, with electrodes arranged together in a cylindrical configuration, can generate field distributions equivalent to commercial DBS leads, and these field distributions can be modulated using field-steering methods. Stimulation with implanted DBS-arrays showed directionally-selective muscle activation, presumably through spread of stimulation fields into portions of the corticospinal tract lying in the internal capsule.

CONCLUSIONS

Our computational and experimental studies demonstrate that the DBS-array is capable of spatially selective stimulation. Displacing VTAs away from the lead's axis can be achieved using a single simple and intuitive control parameter.

SIGNIFICANCE

Optimal DBS likely requires non-uniform VTAs that may differentially affect a nucleus or fiber pathway. The DBS-array allows positioning VTAs with sub-millimeter precision, which is especially relevant for those patients with DBS leads placed in sub-optimal locations. This may present clinicians with an additional degree of freedom to optimize the DBS therapy.

Seasonal peaks in Escherichia coli infections: possible explanations and implications

Escherichia coli is a common cause of infections in all populations and countries of the world, causing an enormous burden of disease. In this issue of Clinical Microbiology and Infection, Al-Hasan et al. describe seasonal peaks in the incidence of E. coli bloodstream infection (BSI) during the summer for a population of 125 000 in Minnesota, USA. We discuss the probability that similar seasonal peaks in the incidence of E. coli BSI occur in other populations and geographical regions. Second, we discuss possible underlying explanations for these findings in terms of seasonal changes in human behaviour and the effect of temperature on the ability of E. coli to survive in the environment. Finally, we discuss some of the possible implications of E. coli BSI being a seasonal illness. More specifically, we discuss how better understanding the reasons for seasonality may potentially help us to better understand the dominant routes by which human populations are exposed to clonal groups of E. coli associated with urinary tract infection.

Comparative phylogeography of brown (Sula leucogaster) and red-footed boobies (S. sula): the influence of physical barriers and habitat preference on gene flow in pelagic seabirds

To test the hypothesis that both physical and ecological barriers to gene flow drive population differentiation in tropical seabirds, we surveyed mitochondrial control region variation in 242 brown boobies (Sula leucogaster), which prefer inshore habitat, and 271 red-footed boobies (S. sula), which prefer pelagic habitat. To determine the relative influence of isolation and gene flow on population structure, we used both traditional methods and a recently developed statistical method based on coalescent theory and Bayesian inference (Isolation with Migration). We found that global population genetic structure was high in both species, and that female-mediated gene flow among ocean basins apparently has been restricted by major physical barriers including the Isthmus of Panama, and the periodic emergence of the Sunda and Sahul Shelves in Southeast Asia. In contrast, the evolutionary history of populations within ocean basins differed markedly between the two species. In brown boobies, we found high levels of population genetic differentiation and limited gene flow among colonies, even at spatial scales as small as 500km. Although red-footed booby colonies were also genetically differentiated within ocean basins, coalescent analyses indicated that populations have either diverged in the face of ongoing gene flow, or diverged without gene flow but recently made secondary contact. Regardless, gene flow among red-footed booby populations was higher than among brown booby populations. We suggest that these contrasting patterns of gene flow within ocean basins may be explained by the different habitat preferences of brown and red-footed boobies.

Pharmacology of alpha7 nicotinic acetylcholine receptor mediated extracellular signal-regulated kinase signalling in PC12 cells

BACKGROUND AND PURPOSE

Neuronal nicotinic acetylcholine receptors (nAChR) can modulate cell survival and memory processing. The involvement of specific nAChR subtypes in downstream signalling events has been ill defined thus far, because of a lack of subtype-selective ligands. In this study, we investigated activation and modulation of alpha7 nAChR-mediated phosphorylation of extracellular signal-regulated kinases (ERK1/2) in PC12 cells, using selective agonists and positive allosteric modulators.

EXPERIMENTAL APPROACH

We used undifferentiated PC12 cells endogenously expressing alpha7 nAChR for both biochemical and functional studies. ERK phosphorylation changes were measured by using a novel In-Cell Western procedure. alpha7 nAChR-mediated Ca(2+) signalling was determined by using the fluorometric imaging plate reader assay.

KEY RESULTS

Robust induction of ERK phosphorylation followed exposure of PC12 cells to the selective agonist PNU-282987 in the presence of the alpha7 nAChR modulator PNU-120596. ERK phosphorylation was transient and was attenuated by the selective antagonist methyllycaconitine. Consistent with allosteric modulation of alpha7 nAChRs, PNU-120596 enhanced both the agonist potency and efficacy in activating ERK. Moreover, alpha7 nAChR agonists could be quantitatively differentiated based on their potency in activating ERK signalling. The rank order of potencies correlated fairly well with the corresponding binding K(i) values of these alpha7 nAChR agonists.

CONCLUSIONS AND IMPLICATIONS

The present work extends previous observations demonstrating the involvement of alpha7 nAChRs in ERK1/2 phosphorylation in PC12 cells. The In-Cell Western procedure allowed a detailed investigation of alpha7 nAChR function and downstream ERK signalling in response to agonist and allosteric modulators.

Cutaneous sensory neurons expressing the Mrgprd receptor sense extracellular ATP and are putative nociceptors

Sensory neurons expressing the Mrgprd receptor are known to innervate the outermost living layer of the epidermis, the stratum granulosum. The sensory modality that these neurons signal and the stimulus that they respond to are not established, although immunocytochemical data suggest they could be nonpeptidergic nociceptors. Using patch clamp of dissociated mouse dorsal root ganglion (DRG) neurons, the present study demonstrates that Mrgprd+ neurons have several properties typical of nociceptors: long-duration action potentials, TTX-resistant Na(+) current, and Ca(2+) currents that are inhibited by mu opioids. Remarkably, Mrgprd+ neurons respond almost exclusively to extracellular ATP with currents similar to homomeric P2X3 receptors. They show little or no sensitivity to other putative nociceptive agonists, including capsaicin, cinnamaldehyde, menthol, pH 6.0, or glutamate. These properties, together with selective innervation of the stratum granulosum, indicate that Mrgprd+ neurons are nociceptors in the outer epidermis and may respond indirectly to external stimuli by detecting ATP release in the skin.

alpha7 nicotinic acetylcholine receptor agonist properties of tilorone and related tricyclic analogues

BACKGROUND AND PURPOSE

The alpha7 nicotinic acetylcholine receptor (nAChR) has attracted considerable interest as a target for cognitive enhancement in schizophrenia and Alzheimer's Disease. However, most recently described alpha7 agonists are derived from the quinuclidine structural class. Alternatively, the present study identifies tilorone as a novel alpha7-selective agonist and characterizes analogues developed from this lead.

EXPERIMENTAL APPROACH

Activity and selectivity were determined from rat brain alpha7 and alpha4beta2 nAChR binding, recombinant nAChR activation, and native alpha7 nAChR mediated stimulation of ERK1/2 phosphorylation in PC12 cells.

KEY RESULTS

Tilorone bound alpha7 nAChR (IC(50) 110 nM) with high selectivity relative to alpha4beta2 (IC(50) 70 000 nM), activated human alpha7 nAChR with an EC(50) value of 2.5 microM and maximal response of 67% relative to acetylcholine, and showed little agonist effect at human alpha3beta4 or alpha4beta2 nAChRs. However, the rat alpha7 nAChR maximal response was only 34%. Lead optimization led to 2-(5-methyl-hexahydro-pyrrolo[3,4-c]pyrrol-2-yl)-xanthen-9-one (A-844606) with improved binding (alpha7 IC(50) 11 nM, alpha4beta2 IC(50)>30 000 nM) and activity at both human and rat alpha7 nAChR (EC(50)s 1.4 and 2.2 microM and apparent efficacies 61 and 63%, respectively). These compounds also activated native alpha7 nAChR, stimulating ERK1/2 phosphorylation in PC12 cells.

CONCLUSIONS AND IMPLICATIONS

Tilorone, known as an interferon inducer, is a selective alpha7 nAChR agonist, suggesting utility of the fluorenone pharmacophore for the development of alpha7 nAChR selective agonists. Whether alpha7 stimulation mediates interferon induction, or whether interferon induction may influence the potential anti-inflammatory properties of alpha7 nAChR agonists remains to be elucidated.

Progesterone receptor expression by human leukocyte cell lines: molecular mechanisms of cytokine suppression

PURPOSE

We investigated progesterone (P) signaling in human leukemia cells, shown to downregulate cytokines with P.

METHODS

The following tests were utilized: PCR with FAM labeled primers and Gene Scan with the Applied Biosystems 373 DNA sequencer for progesterone receptor (PR) mRNA, immunohistochemistry using monoclonal antibodies (Zymed and Ventana) for PR protein, RT-PCR for glucocorticoid receptor (GR), NFkappaB (p65, p50, p52), c-rel, IkappaB-alpha, c-jun, c-fos, mRNA, transient transfections with pNF-kappaB-SEAP, and pGRE-SEAP vectors with chemiluminescence detection for NFkappaB and GR activity.

RESULTS

PR transcripts were demonstrated in MOT, U937, K562, THP-1, 8226, U226, not in JUKAT, HL60, HUT102, isolated normal peripheral blood mononuclear cells, or purified CD4+ or CD8+ T cells. Estradiol increased PR mRNA in MOT and U937. MOT, U937, K562, KG-1, 8226, ATL, and CD8+HTLV-1 expressed PR protein. SRIH-BATL, 729PH6NEO, HS-1, R-CLL, and JURKAT were negative. Steady state mRNA for GR, NFkappaB (p65, p50, p52), IkappaB-alpha, c-jun were unchanged with P in MOT and U937; c-fos and c-rel were not detected. There was a concentration-dependent reduction of NFkappaB activity with P in MOT and U937.

CONCLUSION

The mechanism of cytokine suppression by P is mediated at least in part by suppression of NFkappaB, but the interaction of sex hormones, receptors, and transcription factors is complex.

A SERS-Active System Based on Silver Nanoparticles Tethered to a Deposited Silver Film

A series of SERS-active nanostructures were produced by exposing a freshly deposited silver film (fabricated to be as free from roughness as practicable) to a solution containing a mixture of 1-decanethiol (m) and 1,9-nonanedithiol (d) of varying concentrations of m to d, then allowing colloidal silver nanoparticles to interact with the surface. Silver nanoparticles were found to bind exclusively to films which were prepared from solutions with a nonzero concentration of the dithiol implying that the nanoparticles were tethered to the silver surface by the dithiol with one of the thiolate groups bound to the nanoparticle and the other to the silver film. Intense SERS spectra were observed even from samples in which the m/d concentration ratio was so large that the adsorbed molecules in the vicinity of only approximately 8 +/- 3 nanoparticles were illuminated by the diffraction-limited focused laser beam. At such high dilution, the molecules (numbering at most approximately 330) residing in the SERS "hot spots" associated with the approximately 8 nanoparticles consisted primarily of m (although, of course, for each nanoparticle, at least one molecule in the hot spot had to be d to serve as the linker). This was corroborated by the SERS spectra. An analysis is presented, which accounts for the fact that as the concentration ratio of m/d increases, the SERS intensity associated with bands belonging to m first increases to a maximum then decreases. The nanoparticle-metal film system presented here is a simple embodiment of a more general range of SERS-active sensing platforms in which a molecular tether is used to create a SERS hot spot that (although nanosized) is large enough to accommodate analyte molecules that cannot themselves function as linkers, which are subsequently detected by SERS at the few-molecule level.

Enterococcal prosthetic valve infective endocarditis: report of 45 episodes from the International Collaboration on Endocarditis-merged database

Enterococcal prosthetic valve infective endocarditis (PVE) is an incompletely understood disease. In the present study, patients with enterococcal PVE were compared to patients with enterococcal native valve endocarditis (NVE) and other types of PVE to determine differences in basic clinical characteristics and outcomes using a large multicenter, international database of patients with definite endocarditis. Forty-five of 159 (29%) cases of definite enterococcal endocarditis were PVE. Patients with enterococcal PVE were demographically similar to patients with enterococcal NVE but had more intracardiac abscesses (20% vs. 6%; p=0.009), fewer valve vegetations (51% vs. 79%; p<0.001), and fewer cases of new valvular regurgitation (12% vs. 45%; p=0.01). Patients with either enterococcal PVE or NVE were elderly (median age, 73 vs. 69; p=0.06). Rates of in-hospital mortality, surgical intervention, heart failure, peripheral embolization, and stroke were similar in both groups. Patients with enterococcal PVE were also demographically similar to patients with other types of PVE, but mortality may be lower (14% vs. 26%; p=0.08). Notably, 93% of patients with enterococcal PVE came from European centers, as compared with only 79% of patients with enterococcal NVE (p=0.03). Thus, patients with enterococcal PVE have higher rates of myocardial abscess formation and lower rates of new regurgitation compared to patients with enterococcal NVE, but there are no differences between the groups with regard to surgical or mortality rates. In contrast, though patients with enterococcal PVE and patients with other types of PVE share similar characteristics, mortality is higher in the latter group. Importantly, the prevalence of enterococcal PVE was higher in the European centers in this study.

The Isthmus of Panama: a major physical barrier to gene flow in a highly mobile pantropical seabird

To further test the hypothesis that the Isthmus of Panama is a major barrier to gene flow in pantropical seabirds, we applied phylogeographic methods to mitochondrial control sequence variation in masked booby (Sula dactylatra) populations on either side of the Isthmus of Panama and the southern tip of Africa. In accord with Steeves et al. (2003), we found that all Caribbean masked boobies with the 'secondary contact' cytochrome b haplotype (m-B) shared a control region haplotype (Sd_100), which grouped with Indian-Pacific haplotypes and not Caribbean-Atlantic haplotypes. In addition, Sd_100 was more closely related to control region haplotypes in the Indian Ocean than in the Pacific. We also found that the 'secondary contact' birds diverged more recently from extant populations in the Indian Ocean than in the Pacific. Thus, it appears that these masked boobies did not breach the Isthmus of Panama. Rather, birds likely dispersed around the southern tip of Africa during favourable oceanographic conditions in the Pleistocene.

Enterococcal endocarditis: 107 cases from the international collaboration on endocarditis merged database

PURPOSE

To describe clinical features and outcomes of enterococcal left-sided native valve endocarditis and to compare it to endocarditis caused by other pathogens.

SUBJECTS AND METHODS

Patients in the International Collaboration on Endocarditis-Merged Database were included if they had left-sided native valve endocarditis. Demographic characteristics, clinical features, and outcomes were analyzed. Multivariable analysis evaluated enterococcus as a predictor of mortality.

RESULTS

Of 1285 patients with left-sided native valve endocarditis, 107 had enterococcal endocarditis. Enterococcal endocarditis was most frequently seen in elderly men, frequently involved the aortic valve, tended to produce heart failure rather than embolic events, and had relatively low short-term mortality. Compared to patients with non-enterococcal endocarditis, patients with enterococcal endocarditis had similar rates of nosocomial acquisition, heart failure, embolization, surgery, and mortality. Compared to patients with streptococcal endocarditis, patients with enterococcal endocarditis were more likely to be nosocomially acquired (9 of 59 [15%] vs 2 of 400 [1%]; P <.0001) and have heart failure (49 of 107 [46%] vs 234 of 666 [35%]; P = 0.03). Compared to patients with S. aureus endocarditis, patients with enterococcal endocarditis were less likely to embolize (28 of 107 [26%] vs 155 of 314 [49%]; P <.0001) and less likely to die (12 of 107 [11%] vs 83 of 313 [27%]; P = 0.001). Multivariable analysis of all patients with left-sided native valve endocarditis showed that enterococcal endocarditis was associated with lower mortality (odds ratio [OR] 0.49; 95% confidence interval [CI] 0.24 to 0.97).

CONCLUSIONS

Enterococcal native valve endocarditis has a distinctive clinical picture with a good prognosis.

Risk factors for infective endocarditis in patients with enterococcal bacteremia: a case-control study

BACKGROUND

Based on previous studies, enterococcal infective endocarditis (IE) is considered a unimicrobial, community-acquired disease of older Caucasian men.

PATIENTS AND METHODS

We evaluated the relationship between enterococcal bacteremia and IE by comparing clinical and demographic characteristics of all cases of enterococcal IE within an 8-year period (n = 41) with controls randomly chosen from patients with enterococcal bacteremia without IE.

RESULTS

By univariate and multivariable analyses, the presence of a prosthetic valve (PV) and infection with Enterococcus faecalis were significantly associated with IE, while age, gender, race, polymicrobial infection and community-acquired infection were not. Almost an equal number of women and men had enterococcal IE. Cases of enterococcal IE were commonly nosocomial (39%) and polymicrobial (17%).

CONCLUSIONS

Enterococcal endocarditis can no longer be considered exclusively a unimicrobial, community-acquired disease of Caucasian men. Instead, our data suggest that the presence of a PV and infection by E. faecalis are associated with an increased risk for IE.

Stroke location, characterization, severity, and outcome in mitral vs aortic valve endocarditis

OBJECTIVE

To characterize the incidence and clinical features of patients with infective endocarditis (IE) and stroke.

METHODS

The authors reviewed the records of 707 patients diagnosed with definite or possible IE between January 1984 and November 1999. Stroke was confirmed by application of strict definitions and classified by type, pathophysiology, vascular territory, and severity. The authors determined mortality rates for the initial hospitalization and 12 months after admission.

RESULTS

Strokes occurred in 68 (9.6%) of 707 patients with IE, 38 (17%) of 218 patients with mitral valve endocarditis (MVE), 14 (9%) of 149 patients with aortic valve endocarditis (AVE), and 16 (5%) of 340 patients with other forms of IE (OR for MVE vs AVE = 2.0, 95% CI 1.1 to 3.9). Among the patients with MVE or AVE and stroke, there were no significant relationships between site of vegetation and length of hospitalization, stroke severity, mortality during the initial hospitalization, or 12-month mortality. Fifty-two percent of patients with stroke and IE died within 1 year of admission.

CONCLUSIONS

The overall incidence of stroke in patients with IE (9.6%) is lower than previous reports (21 to 39%). Patients with MVE had a greater risk of stroke than patients with AVE. Fifty-two percent of patients died within 1 year of admission for IE.

Actuarial and reproductive senescence in a long-lived seabird: preliminary evidence

The evolutionary theory of aging predicts that pelagic seabirds, which have low extrinsic mortality, should show exceptional longevity. These taxa appear to show the lowest rates of actuarial senescence among birds yet display declining reproductive performance at advanced ages. We have studied survival and reproduction of Nazca boobies (Sula granti) in the remote Galápagos Islands since 1984. We found a slight but detectable increase in mortality rate in the oldest (> or =19 yrs) cohort, indicating minimal actuarial senescence. The probability of successful reproduction (eggs or fledglings) declined from mid-life to the age of the oldest cohort. We are currently investigating the causal relationship between physical (foraging) performance, components of reproductive success, and longevity at our pristine study site.

T helper 1-type immunity to trophoblast antigens in women with a history of recurrent pregnancy loss is associated with polymorphism of the IL1B promoter region

Recurrent pregnancy loss (RPL) is a common disorder during early gestation. Recent evidence suggests that T helper 1 (Th1)-type immunity is associated with unsuccessful pregnancy especially in women with RPL of otherwise unknown etiology, while Th2-type immunity is associated with pregnancy success. Interleukin (IL)-1 may influence Th1/Th2 immune responsiveness and has been implicated in the establishment of successful pregnancy. In the present study, we investigated polymorphism of the IL-1beta gene (IL1B) in women with a history of RPL. Significant increases in the frequencies of IL1B promoter region variants IL1-511C and IL1B-31T were found in women with a history of RPL. Increased frequencies of these two variants and their homozygotes were found only in cases having evidence of Th1 immunity to trophoblast as determined by IFN-gamma production of peripheral blood mononuclear cells (PBMCs) stimulated with a trophoblast cell-line extract. Significantly higher IFN-gamma production by PBMCs in response to trophoblast correlated with variant IL1B-511C and its homozygocity in women with RPL. These results suggest that variants -511C and -31T in the IL1B promoter region confer risk for RPL associated with Th1 immunity to trophoblast antigens.

Stem and progenitor cells: origins, phenotypes, lineage commitments, and transdifferentiations

Multipotent stem cells are clonal cells that self-renew as well as differentiate to regenerate adult tissues. Whereas stem cells and their fates are known by unique genetic marker studies, the fate and function of these cells are best studied by their prospective isolation. This review is about the properties of various highly purified tissue-specific multipotent stem cells and purified oligolineage progenitors. We contend that unless the stem or progenitor cells in question have been purified to near homogeneity, one cannot know whether their generation of expected (or unexpected) progeny is a property of a known cell type. It is interesting that in the hematopoietic system the only long-term self-renewing cells in the stem and progenitors pool are the hematopoietic stem cells. This fact is discussed in the context of normal and leukemic hematopoiesis.

The bHLH transcription factor Olig2 promotes oligodendrocyte differentiation in collaboration with Nkx2.2

Olig2, a basic helix-loop-helix (bHLH) transcription factor, is expressed in a restricted domain of the spinal cord ventricular zone that sequentially generates motoneurons and oligodendrocytes. Just prior to oligo-dendrocyte precursor formation, the domains of Olig2 and Nkx2.2 expression switch from being mutually exclusive to overlapping, and Neurogenins1 and 2 are extinguished within this region. Coexpression of Olig2 with Nkx2.2 in the spinal cord promotes ectopic and precocious oligodendrocyte differentiation. Both proteins function as transcriptional repressors in this assay. This effect is blocked by forced expression of Neurogenin1. By contrast, misexpression of Olig2 alone derepresses Neurogenins and promotes motoneuron differentiation. Olig2 therefore functions sequentially in motoneuron and oligodendrocyte fate specification. This dual action is enabled by spatio-temporal changes in the expression domains of other transcription factors with which Olig2 functionally interacts.

A diverse family of GPCRs expressed in specific subsets of nociceptive sensory neurons

In vertebrates, peripheral chemosensory neurons express large families of G protein-coupled receptors (GPCRs), reflecting the diversity and specificity of stimuli they detect. However, somatosensory neurons, which respond to chemical, thermal, or mechanical stimuli, are more broadly tuned. Here we describe a family of approximately 50 GPCRs related to Mas1, called mrgs, a subset of which is expressed in specific subpopulations of sensory neurons that detect painful stimuli. The expression patterns of mrgs thus reveal an unexpected degree of molecular diversity among nociceptive neurons. Some of these receptors can be specifically activated in heterologous cells by RFamide neuropeptides such as NPFF and NPAF, which are analgesic in vivo. Thus, mrgs may regulate nociceptor function and/or development, including the sensation or modulation of pain.

The molecular basis of nonoxynol-9-induced vaginal inflammation and its possible relevance to human immunodeficiency virus type 1 transmission

Topical microbicides are being sought to prevent sexually transmitted diseases by inactivating pathogens while preserving or enhancing the natural mucosal barrier. Serious public health concerns were raised by a recent phase 3 clinical trial that showed that nonoxynol-9 (N-9), a leading microbicide candidate widely used as an over-the-counter spermicide, may actually increase human immunodeficiency virus type 1 (HIV-1) transmission. The present study links N-9-induced vaginal inflammation to increased risk of HIV-1 infection. Analysis of molecular and cellular components in cervicovaginal secretions, as well as results from in vitro activation of cervicovaginal epithelial cells and U1/HIV promonocytic cells, showed that multiple N-9 use can promote HIV-1 transmission through interleukin-1-mediated NF-kappaB activation, which leads to chemokine-induced recruitment of HIV-1 host cells and increased HIV-1 replication in infected cells. Furthermore, this study identifies in vitro and in vivo model systems for monitoring undesirable proinflammatory effects of microbicides and other vaginal products.

Hormonal correlates of siblicide in Galápagos Nazca boobies

Nazca boobies (Sula granti) show unconditional obligate siblicide immediately after hatching, reducing the typical two-egg clutch size to one. We studied body mass changes and levels of testosterone (T), corticosterone (CORT), and progesterone (P) for A-chicks (dominant, first hatched), B-chicks (subordinate, second hatched), and singletons, during the first 7 days after hatching, when siblicide normally occurs. Mass increase with age was higher for A-chicks than for singletons and B-chicks. This exaggerated the existing developmental advantage of A- over B-chicks that is due to hatching asynchrony. In nests with two chicks, CORT titer was significantly higher in B-chicks than in A-chicks. During ontogenetic development, CORT decreased with age for A-chicks, but did not change for singletons. P showed qualitatively similar ontogenetic changes to CORT, remaining unchanged for A-chicks but increasing for singletons. Thus, both CORT and P levels were lower for A-chicks than for singletons, and both hormones varied inversely with body mass. Overall, T levels did not differ between different categories of chicks. However, one B-chick in the process of reversing the dominance relationship with its older, but weakened, sibling had significantly elevated T. We suggest that CORT and P are regulated to promote exaggerated mass gain in socially challenged A-chicks, facilitating siblicide. Whether T induces aggressiveness during short time intervals of intense sibling rivalry needs further attention.

Surface modification of neural recording electrodes with conducting polymer/biomolecule blends

The interface between micromachined neural microelectrodes and neural tissue plays an important role in chronic in vivo recording. Electrochemical polymerization was used to optimize the surface of the metal electrode sites. Electrically conductive polymers (polypyrrole) combined with biomolecules having cell adhesion functionality were deposited with great precision onto microelectrode sites of neural probes. The biomolecules used were a silk-like polymer having fibronectin fragments (SLPF) and nonapeptide CDPGYIGSR. The existence of protein polymers and peptides in the coatings was confirmed by reflective microfocusing Fourier transform infrared spectroscopy (FTIR). The morphology of the coating was rough and fuzzy, providing a high density of bioactive sites for interaction with neural cells. This high interfacial area also helped to lower the impedance of the electrode site and, consequently, to improve the signal transport. Impedance spectroscopy showed a lowered magnitude and phase of impedance around the biologically relevant frequency of 1 kHz. Cyclic voltammetry demonstrated the intrinsic redox reaction of the doped polypyrrole and the increased charge capacity of the coated electrodes. Rat glial cells and human neuroblastoma cells were seeded and cultured on neural probes with coated and uncoated electrodes. Glial cells appeared to attach better to polypyrrole/SLPF-coated electrodes than to uncoated gold electrodes. Neuroblastoma cells grew preferentially on and around the polypyrrole/CDPGYIGSR-coated electrode sites while the polypyrrole/CH(3)COO(-)-coated sites on the same probe did not show a preferential attraction to the cells. These results indicate that we can adjust the chemical composition, morphology, electronic transport, and bioactivity of polymer coatings on electrode surfaces on a multichannel micromachined neural probe by controlling electrochemical deposition conditions.

Cardiac conduction abnormalities in endocarditis defined by the Duke criteria

BACKGROUND

Cardiac conduction abnormalities occur in endocarditis and have been associated with infection extension and increased mortality. There have been no prospective studies of electrocardiographic (ECG) conduction changes in endocarditis. We examined the incidence of ECG changes in a large prospective cohort with suspected endocarditis and correlated changes with echocardiographic evidence of invasive infection and mortality.

METHODS

One hundred thirty-seven of 1396 (10%) suspected cases of endocarditis were classified as "definite" or "possible" by the Duke criteria and had an interpretable ECG. ECG conduction changes were classified as old (pre-existing hospitalization), new (evident on admission or developed during hospitalization), or indeterminate. New or indeterminate abnormalities were considered "ECG conduction changes." Echocardiogram results were reviewed to identify infected valves and invasive infection.

RESULTS

ECG conduction changes were present in 36 of 137 (26%) patients. Patients with ECG conduction changes were more often male (69% vs 46%, P =.005) and had prosthetic valves (47% vs 23%, P <.001). There were no significant differences in microbiology results or treatment with cardiac surgery. In 76 (55%) patients, at least one infected valve was identified by echocardiography; 15 of 76 (20%) patients were determined to have evidence of invasive infection. Eight of 15 (53%) invasive infections exhibited ECG conduction changes compared with 16 of 61 (26%) isolated valve infections (P =.046). Eleven of 36 (31%) patients with ECG conduction changes died during hospitalization compared with 15 of 101 (15%) patients without changes (P =.039).

CONCLUSIONS

ECG conduction changes commonly occur in endocarditis despite more sensitive diagnostic criteria and are associated with increased mortality and invasive infection.

The paired homeodomain protein DRG11 is required for the projection of cutaneous sensory afferent fibers to the dorsal spinal cord

Cutaneous sensory neurons that detect noxious stimuli project to the dorsal horn of the spinal cord, while those innervating muscle stretch receptors project to the ventral horn. DRG11, a paired homeodomain transcription factor, is expressed in both the developing dorsal horn and in sensory neurons, but not in the ventral spinal cord. Mouse embryos deficient in DRG11 display abnormalities in the spatio-temporal patterning of cutaneous sensory afferent fiber projections to the dorsal, but not the ventral spinal cord, as well as defects in dorsal horn morphogenesis. These early developmental abnormalities lead, in adults, to significantly attenuated sensitivity to noxious stimuli. In contrast, locomotion and sensori-motor functions appear normal. Drg11 is thus required for the formation of spatio-temporally appropriate projections from nociceptive sensory neurons to their central targets in the dorsal horn of the spinal cord.

Treatment of femoral fractures in children by pediatric orthopedists: results of a 1998 survey

SUMMARY

This study aimed to determine treatment preference of various femoral fracture patterns in children by pediatric orthopedists and whether it is practice dependent. In September 1998, members of the Pediatric Orthopedic Society of North America were surveyed to determine their current preferences in treating each of four middle one-third femoral fracture patterns in four age groups. Forty-four percent (286/656) of those surveyed responded. For each fracture pattern, operative treatment was increasingly preferred over nonoperative as patient age increased, and the preferred treatments within the operative and nonoperative categories changed significantly as patient age increased. Fourteen specific cases of femoral head avascular necrosis were noted after rigid reamed and unreamed rodding. There is a statistically significant trend by pediatric orthopedists to treat older children's femur fractures operatively and younger children's nonoperatively. The consensus treatment is age dependent. The numerous cases of avascular necrosis after rigid rodding are a concern.

The risk of stroke and death in patients with aortic and mitral valve endocarditis

BACKGROUND

Previous studies have generated inconsistent results when attempting to define predictors of stroke and death in patients with endocarditis. We sought to examine the relationship between vegetation 2-dimensional size and stroke in those with infective endocarditis (IE) and to identify differences between aortic valve (AV) and mitral valve (MV) IE with regard to clinical characteristics, echocardiographic findings, stroke, and death.

METHODS

We used the Duke Endocarditis Database to examine 145 episodes of definite IE involving the AV, n = 62, or MV, n = 83. A logistic regression model was developed to analyze important variables in predicting stroke, and a Cox proportional hazards model was used in predicting mortality.

RESULTS

The mitral valve was infected in 57% of the cases. Vegetations were more commonly detected in patients with MV IE (92.8% vs 66.1%, P =.001) and these MV vegetations were significantly larger (P <.05). Thirty-four of 145 episodes (23.4%) were complicated by stroke. MV IE was associated with a greater stroke rate, 32.5% versus 11.3% (P =.003). Strokes tended to occur early in the course of illness, particularly in MV IE. In the multivariable model, the independent predictors of stroke were MV IE (P =.04) and vegetation length (P =.03). Independent predictors of 1-year mortality were age (P =.02) and vegetation area (P =.048).

CONCLUSION

Stroke is more common in patients with MV IE. Vegetation 2-dimensional size and characteristics are important predictors of stroke and mortality. These findings may lead to predictive models that allow physicians to identify high-risk patients who need aggressive treatment strategies to prevent long-term morbidity and mortality.

A systems approach to the reduction of medication error on the hospital ward

AIMS

To discuss a potentially powerful approach to safer medication administration on the hospital ward, based on principles of safety developed in other high-risk industries, and consistent with recent national reports on safety in health care released in the United Kingdom (UK) and United States of America (USA). To discuss why punitive approaches to safety on the hospital ward and in the nursing literature do not work.

BACKGROUND

Drug administration error on the hospital ward is an ever-present problem and its occurrence is too frequent. Administering medication is probably the highest-risk task a nurse can perform, and accidents can lead to devastating consequences for the patient and for the nurse's career. Drug errors in nursing are often dealt with by unsystematic, punitive, and ineffective means, with little knowledge of the factors influencing error generation. Typically, individual nurses are simply blamed for their carelessness. By focusing on the individual, the complete set of contributing factors cannot be known. Instead, vain attempts will be made to change human behaviour - one of the most change-resistant aspects of any system. A punitive, person-centred approach therefore, severely hampers effective improvements in safety. By contrast, in other high-risk industries, such as aviation and nuclear power, the systems-centred approach to error reduction is routine.

CONCLUSIONS

Accidents or errors are only the tip of the incident iceberg. Through effective, nonpunitive incident reporting, which includes reports of near-misses and system problems in addition to actual accidents, the systems-approach allows the complete set of contributing factors underlying an accident to be understood and addressed. Feedback to participants and targeted improvement in the workplace is also important to demonstrate that incident data are being used appropriately, and to maintain high levels of on-going reporting and enthusiasm for the scheme. Drug administration error is a serious problem, which warrants a well-reasoned approach to its improvement.

Leukocyte activation in the decidua of chromosomally normal and abnormal fetuses from women with recurrent abortion

As part of our continuing programme to investigate immunological causes of unexplained recurrent pregnancy losses, we studied subpopulations of white blood cells and their activation status in decidua of women with a history of recurrent spontaneous abortion (RSA). We differentiated specifically between normal karyotyped male fetuses and abnormal karyotyped fetuses with trisomy 16 because trisomy 16 is not compatible with life and is thus a non-controversial cause of spontaneous miscarriage. Leukocytes were counted in paraffin-embedded decidua after immunohistological staining for CD45 (LCA), CD3, CD56, CD68, CD69 and CD25. Numbers of activated versus non-activated T lymphocytes, NK cells and macrophages were compared in decidua from women with: (i) unexplained RSA who had a normal male karyotype (n = 17) miscarriage; (ii) unexplained RSA who had a trisomy 16 (n = 21) miscarriage; and (iii) normal gestationally age-matched first trimester pregnancies following elective termination procedures (n = 20). Significantly more activated leukocytes were detected in the decidua of women with unexplained RSA who had a normal male karyotype compared to the other groups (P < 0.0001). In addition, numbers of cells comprising the major leukocyte subpopulation, CD56+ NK cells, appeared reduced in the decidua of women with unexplained RSA compared to decidua from women having elective terminations. Increased numbers of activated leukocytes in the decidua of women with a history of unexplained recurrent pregnancy loss who had a normal karyotyped pregnancy provide evidence that cellular immunity may be involved in unexplained recurrent pregnancy loss.

Cost-effectiveness of spinal cord stimulation in patients with intractable angina

AIM

To review the cost of healthcare utilisation by patients suffering from intractable angina, unsuitable for coronary revascularisation, before and after treatment with spinal cord stimulation.

METHODS

Data were collected for eight patients treated for intractable angina with spinal cord stimulation at Green Lane Hospital before April 1999. Information on consumption of specified medica resources for the twelve months preceding implantation, the implantation period, and the twelve months following implantation was collected. Where available, data were also collected for the eighteen months preceding and following treatment.

RESULTS

In six patients successful permanent stimulation was established; in two it proved technically impossible to implant a stimulator. The six patients with successful stimulation spent fewer days in hospital (p=0.028) and consumed fewer resources (p=0.046) following implantation than in the period before implantation. The two patients for whom spinal cord stimulation was unsuccessful spent more days in hospital and consumed more resources in the twelve months following, than in the twelve months preceding attempted implantation. Extrapolation of data for all eight patients suggests that, on average, the cost of implanting a spinal cord stimulator will be recovered in approximately fifteen months.

CONCLUSION

Spinal cord stimulation is a cost-effective treatment for intractable angina pectoris.

Amygdala-enriched genes identified by microarray technology are restricted to specific amygdaloid subnuclei

Microarray technology represents a potentially powerful method for identifying cell type- and regionally restricted genes expressed in the brain. Here we have combined a microarray analysis of differential gene expression among five selected brain regions, including the amygdala, cerebellum, hippocampus, olfactory bulb, and periaqueductal gray, with in situ hybridization. On average, 0.3% of the 34,000 genes interrogated were highly enriched in each of the five regions, relative to the others. In situ hybridization performed on a subset of amygdala-enriched genes confirmed in most cases the overall region-specificity predicted by the microarray data and identified additional sites of brain expression not examined on the microarrays. Strikingly, the majority of these genes exhibited boundaries of expression within the amygdala corresponding to cytoarchitectonically defined subnuclei. These results define a unique set of molecular markers for amygdaloid subnuclei and provide tools to genetically dissect their functional roles in different emotional behaviors.

Behavioral effects of diazepam and propranolol in patients with panic disorder and agoraphobia

The effects of oral doses of diazepam (single dose of 10 mg and a median dose of 30 mg/day for 2 weeks) and propranolol (single dose of 80 mg and a median dose of 240 mg/day for 2 weeks) on psychological performance of patients with panic disorders and agoraphobia were investigated in a double-blind, randomized and crossover design. Both drugs impaired immediate free recall but the decrease was greater for diazepam than propranolol. Delayed free recall was also impaired but the two drugs did not differ. Patients tapped faster after propranolol than diazepam and they were more sedated after diazepam than propranolol. After 2 weeks of treatment, patients tested 5-8 h after the last dose of medication did not show any decrement of performance. These results are similar to those previously found in healthy subjects. Accumulation of drugs was not reflected in prolonged behavioral impairment.

Quantitative Analysis of Bacterial and Mammalian Proteomes Using a Combination of Cysteine Affinity Tags and 15N-Metabolic Labeling

We describe the combined use of 15N-metabolic labeling and a cysteine-reactive biotin affinity tag to isolate and quantitate cysteine-containing polypeptides (Cys-polypeptides) from Deinococcus radiodurans as well as from mouse B16 melanoma cells. D. radiodurans were cultured in both natural isotopic abundance and 15N-enriched media. Equal numbers of cells from both cultures were combined and the soluble proteins extracted. This mixture of isotopically distinct proteins was derivatized using a commercially available cysteine-reactive reagent that contains a biotin group. Following trypsin digestion, the resulting modified peptides were isolated using immobilized avidin. The mixture was analyzed by capillary reversed-phase liquid chromatography (LC) online with ion trap mass spectrometry (MS) as well as Fourier transform ion cyclotron resonance (FTICR) MS. The resulting spectra contain numerous pairs of Cyspolypeptides whose mass difference corresponds to the number of nitrogen atoms present in each of the peptides. Designation of Cys-polypeptide pairs is also facilitated by the distinctive isotopic distribution of the 15N-labeled peptides versus their 14N-labeled counterparts. Studies with mouse B16 cells maintained in culture allowed the observation of hundreds of isotopically distinct pairs of peptides by LC-FTICR analysis. The ratios of the areas of the pairs of isotopically distinct peptides showed the expected 1:1 labeling of the 14N and 15N versions of each peptide. An additional benefit from the present strategy is that the 15N-labeled peptides do not display significant isotope-dependent chromatographic shifts from their 14N-labeled counterparts, therefore improving the precision for quantitating peptide abundances. The methodology presented offers an alternate, cost-effective strategy for conducting global, quantitative proteomic measurements.

Synthesis and structure-activity relationships of 5-substituted pyridine analogues of 3

In an effort to probe the steric influence of C5 substitution of the pyridine ring on CNS binding affinity, analogues of 1 substituted with a bulky moiety--such as phenyl, substituted phenyl, or heteroaryl-were synthesized and tested in vitro for neuronal nicotinic acetylcholine receptor binding affinity. The substituted analogues exhibited Ki values ranging from 0.055 to 0.69 nM compared to a Ki value of 0.15 nM for compound 1. Assessment of functional activity at subtypes of neuronal nicotinic acetylcholine receptors led to identify several agonists and antagonists.