Latent profiles of autism symptoms in children and adolescents with Down syndrome

BACKGROUND

Down syndrome (DS) is associated with elevated rates of autism spectrum disorder (ASD) and autism symptomatology. To better characterise heterogeneity in ASD symptomatology in DS, profiles of caregiver-reported ASD symptoms were modelled for children and adolescents with DS.

METHODS

Participants (n = 125) were recruited through several multi-site research studies on cognition and language in DS. Using the Social Responsiveness Scale-2 (SRS-2; Constantino and Gruber 2012), two latent profile analyses (LPA) were performed, one on the broad composite scores of social communication and interaction and restricted interests and repetitive behaviour, and a second on the four social dimensions of social communication, social motivation, social awareness, and social cognition.

RESULTS

A three-profile model was the best fit for both analyses, with each analysis yielding a low ASD symptom profile, an elevated or mixed ASD symptom profile and a high ASD symptom profile. Associations were observed between profile probability scores and IQ, the number of co-occurring biomedical conditions reported, sex, and SRS-2 form.

CONCLUSIONS

Characterising heterogeneity in ASD symptom profiles can inform more personalised supports in this population, and implications for potential therapeutic approaches for individuals with DS are discussed.

Effect of pulsed electromagnetic fields stimulation on ischemic skin model

This study aimed to evaluate the effect of Pulsed Electromagnetic Fields (PEMF) in improving blood flow reduction and tissue necrosis of ischemic animal induced by skin flap. In each experiment, twenty rats (280-320 g) were randomly divided into control group (n = 10) and PEMF (n = 10) group. All of the rats were performed skin flap in back. In the PEMF group, PEMF (1 Hz, 10 mT) was performed in each experiment. In Experiment-1 (n = 20), PEMF was performed for 90 minutes. In Experiment-2 (n = 20), additionally, a blocking film was inserted, and suture was performed to induce necrosis. PEMF was performed for 30 minutes each day for 7 days. As a result of Speckle-Flow Index (SFI) analysis, in the control group, blood flow continued to decrease immediately after the procedure. In the PEMF group, blood flow was remained constant after 30 minutes and increased after 60 minutes. The blood flow in a specific region substantially increased from the initial state. As a result of skin necrosis analysis, the progression rate in the PEMF group was slower than that of the control group. The rate of necrosis in the PEMF group decreased dramatically from the 6th day, and there was a statistically significant difference between the two groups at the 7th day (p < .05). In this study, it was confirmed that PEMF (1 Hz, 10 mT) has a blood flow improvement and skin tissue necrosis alleviation in the ischemic flap animal model.

GZ-11608, a Vesicular Monoamine Transporter-2 Inhibitor, Decreases the Neurochemical and Behavioral Effects of Methamphetamine

Despite escalating methamphetamine use and high relapse rates, pharmacotherapeutics for methamphetamine use disorders are not available. Our iterative drug discovery program had found that R-N-(1,2-dihydroxypropyl)-2,6-cis-di-(4-methoxyphenethyl)piperidine hydrochloride (GZ-793A), a selective vesicular monoamine transporter-2 (VMAT2) inhibitor, specifically decreased methamphetamine's behavioral effects. However, GZ-793A inhibited human-ether-a-go-go-related gene (hERG) channels, suggesting cardiotoxicity and prohibiting clinical development. The current study determined if replacement of GZ-793A's piperidine ring with a phenylalkyl group to yield S-3-(4-methoxyphenyl)-N-(1-phenylpropan-2-yl)propan-1-amine (GZ-11608) diminished hERG interaction while retaining pharmacological efficacy. VMAT2 inhibition, target selectivity, and mechanism of GZ-11608-induced inhibition of methamphetamine-evoked vesicular dopamine release were determined. We used GZ-11608 doses that decreased methamphetamine-sensitized activity to evaluate the potential exacerbation of methamphetamine-induced dopaminergic neurotoxicity. GZ-11608-induced decreases in methamphetamine reinforcement and abuse liability were determined using self-administration, reinstatement, and substitution assays. Results show that GZ-11608 exhibited high affinity (K_i = 25 nM) and selectivity (92-1180-fold) for VMAT2 over nicotinic receptors, dopamine transporter, and hERG, suggesting low side-effects. GZ-11608 (EC₅₀ = 620 nM) released vesicular dopamine 25-fold less potently than it inhibited VMAT2 dopamine uptake. GZ-11608 competitively inhibited methamphetamine-evoked vesicular dopamine release (Schild regression slope = 0.9 ± 0.13). GZ-11608 decreased methamphetamine sensitization without altering striatal dopamine content or exacerbating methamphetamine-induced dopamine depletion, revealing efficacy without neurotoxicity. GZ-11608 exhibited linear pharmacokinetics and rapid brain penetration. GZ-11608 decreased methamphetamine self-administration, and this effect was not surmounted by increasing methamphetamine unit doses. GZ-11608 reduced cue- and methamphetamine-induced reinstatement, suggesting potential to prevent relapse. GZ-11608 neither served as a reinforcer nor substituted for methamphetamine, suggesting low abuse liability. Thus, GZ-11608, a potent and selective VMAT2 inhibitor, shows promise as a therapeutic for methamphetamine use disorder. SIGNIFICANCE STATEMENT: GZ-11608 is a potent and selective vesicular monoamine transporter-2 inhibitor that decreases methamphetamine-induced dopamine release from isolated synaptic vesicles from brain dopaminergic neurons. Results from behavioral studies show that GZ-11608 specifically decreases methamphetamine-sensitized locomotor activity, methamphetamine self-administration, and reinstatement of methamphetamine-seeking behavior, without exhibiting abuse liability. Tolerance does not develop to the efficacy of GZ-11608 to decrease the behavioral effects of methamphetamine. In conclusion, GZ-11608 is an outstanding lead in our search for a therapeutic to treat methamphetamine use disorder.

Muscarinic agonist, (±)-quinuclidin-3-yl-(4-fluorophenethyl)(phenyl)carbamate: High affinity, but low subtype selectivity for human M1 - M5 muscarinic acetylcholine receptors

Novel quinuclidinyl N-phenylcarbamate analogs were synthesized, and binding affinities at M1-M5 muscarinic acetylcholine receptor (mAChR) subtypes were determined using Chinese hamster ovary (CHO) cell membranes stably expressing one specific subtype of human mAChR. Although not subtype selective, the lead analog (±)-quinuclidin-3-yl-(4-fluorophenethyl)(phenyl)carbamate (3c) exhibited the highest affinity (Ki = 2.0, 13, 2.6, 2.2, 1.8 nM) at each of the M1-M5 mAChRs, respectively. Based on results from the [3H]dopamine release assay using rat striatal slices, 3c acted as an agonist at mAChRs. The effect of 3c was inhibited by the nonselective mAChR antagonist, scopolamine, and 3c augmented release evoked by oxotremorine. A potent analog from the same scaffold, (±)-quinuclidin-3-yl-(4-methoxyphenethyl)(phenyl)-carbamate (3b) exhibited the greatest selectivity (17-fold) at M3 over M2 mAChRs. These analogs could serve as leads for further discovery of novel subtype-selective muscarinic ligands with the goal of providing therapeutics for substance use disorders and chronic obstructive pulmonary disease.

New Scaffold for Lead Compounds to Treat Methamphetamine Use Disorders

Despite increased methamphetamine use worldwide, pharmacotherapies are not available to treat methamphetamine use disorder. The vesicular monoamine transporter-2 (VMAT2) is an important pharmacological target for discovery of treatments for methamphetamine use disorder. VMAT2 inhibition by the natural product, lobeline, reduced methamphetamine-evoked dopamine release, methamphetamine-induced hyperlocomotion, and methamphetamine self-administration in rats. Compared to lobeline, lobelane exhibited improved affinity and selectivity for VMAT2 over nicotinic acetylcholine receptors. Lobelane inhibited neurochemical and behavioral effects of methamphetamine, but tolerance developed to its behavioral efficacy in reducing methamphetamine self-administration, preventing further development. The lobelane analog, R-N-(1,2-dihydroxypropyl)-2,6-cis-di-(4-methoxyphenethyl)piperidine hydrochloride (GZ-793A), potently and selectively inhibited VMAT2 function and reduced neurochemical and behavioral effects of methamphetamine. However, GZ-793A exhibited potential to induce ventricular arrhythmias interacting with human-ether-a-go-go (hERG) channels. Herein, a new lead, R-3-(4-methoxyphenyl)-N-(1-phenylpropan-2-yl)propan-1-amine (GZ-11610), from the novel scaffold (N-alkyl(1-methyl-2-phenylethyl)amine) was evaluated as a VMAT2 inhibitor and potential therapeutic for methamphetamine use disorder. GZ-11610 was 290-fold selective for VMAT2 over dopamine transporters, suggesting that it may lack abuse liability. GZ-11610 was 640- to 3500-fold selective for VMAT2 over serotonin transporters and nicotinic acetylcholine receptors. GZ-11610 exhibited > 1000-fold selectivity for VMAT2 over hERG, representing a robust improvement relative to our previous VMAT2 inhibitors. GZ-11610 (3-30 mg/kg, s.c. or 56-300 mg/kg, oral) reduced methamphetamine-induced hyperactivity in methamphetamine-sensitized rats. Thus, GZ-11610 is a potent and selective inhibitor of VMAT2, may have low abuse liability and low cardiotoxicity, and after oral administration is effective and specific in inhibiting the locomotor stimulant effects of methamphetamine, suggesting further investigation as a potential therapeutic for methamphetamine use disorder.

Simultaneous detection of barrier- and immune-related gene variations in patients with atopic dermatitis by reverse blot hybridization assay

BACKGROUND

Hereditary factors are involved in the pathogenesis of atopic dermatitis (AD). However, AD-related gene variations are significantly different across ethnicities.

AIM

To identify mutations and single-nucleotide polymorphisms (SNPs) in barrier- or immune-related genes from Korean patients with AD and compare the variations with those observed in nonatopic healthy controls (HCs), and to use novel reverse blot hybridization assay (REBA) for AD-related gene variants.

METHODS

We carried out REBA to simultaneously detect variations in genes related to barrier or immune function, namely, FLG, SPINK5, KLK7, DEFB1, TNFα, KDR, FCER1A, IL4, IL5,IL5RA, IL9, IL10, IL12, IL12R, IL13 and IL18, from Korean patients with AD, and compared the variation to that in nonatopic healthy controls.

RESULTS

The homozygous mutants of KLK7 and SPINK5-2475, and the heterozygous mutants of FLG 3321delA, SPINK5-1156, DEFB1, KDR, IL5RA, IL9 and IL12RB1 were significantly more frequent in AD. It has been predicted that the larger the number of gene variants, the higher the odds ratio of AD prevalence; however, we did not find any significant correlation between the number of gene variants and AD severity.

CONCLUSION

Using REBA, we identified more genetic variants that can predict AD occurrence. We also verified that REBA can be used to easily and accurately detect multiple AD-related gene variants simultaneously. In addition, we identified a correlation between KLK7 mutation and AD in Koreans, which is the first such report, to our knowledge.

Appropriate non-carbapenems are not inferior to carbapenems as initial empirical therapy for bacteremia caused by extended-spectrum beta-lactamase-producing Enterobacteriaceae: a propensity score weighted multicenter cohort study

The efficacy of empirical non-carbapenem antibiotics for extended-spectrum beta-lactamase-producing Enterobacteriaceae bacteremia (ESBL-B) is still inconclusive. We conducted a multicenter retrospective cohort study to evaluate the efficacy of empirical non-carbapenem antibiotics for treating ESBL-B. Electronic medical records of individuals who were diagnosed with ESBL-B were reviewed between January 2010 and December 2014 at four university hospitals in Korea. Patients were classified into non-carbapenem and carbapenem groups according to the empirical antibiotic regimen. Patients treated with appropriate empirical antibiotics and who subsequently received carbapenems as definitive therapy were included in the analysis. The inverse probability of treatment weights, a statistical method that adjusts baseline statistics by giving weights based on propensity score, was used. During the study period, 232 adequately treated patients with ESBL-B were included in the analysis: 49 patients in the non-carbapenem group and 183 in the carbapenem group. The baseline characteristics and severity of infection were similar after propensity score weighting. The 30-day mortality rates for the two groups were not statistically significantly different (non-carbapenems 6.3% and carbapenems 11.4%; P = 0.42). In a multivariate analysis, empirical treatment with non-carbapenem antibiotics was not associated with 30-day all-cause mortality (HR 1.02, 95% CI 0.99-1.06, P = 0.14). In a subgroup analysis, empirical treatment with piperacillin-tazobactam was also not associated with 30-day all-cause mortality (HR 1.21, 95% CI 0.37-4.00, P = 0.75). Appropriate non-carbapenems were not inferior to carbapenems as initial empirical therapy for ESBL-B.

Maximal strength and endurance scores of the tongue, lip, and cheek in healthy, normal Koreans

Objectives

The purpose of this study was to establish normative data for healthy Korean adults by measuring the maximal strength and endurance scores of the tongue, lip, and cheek, and to examine correlations between these measurements.

Materials and Methods

This study included 120 subjects that were divided into three groups according to age: young (20-39 years), middle-aged (40-59 years), and older (over 60 years); and by gender. Measurements were taken using the Iowa Oral Performance Instrument (IOPI).

Results

The mean maximal tongue strengths were as follows: young men (46.7±10.2 kPa) and women (32.1±7.9 kPa), middle-aged men (40.9±9.3 kPa) and women (36.9±8.6 kPa), and older men (35.2±9.0 kPa) and women (34.5±6.9 kPa). The mean tongue endurance scores were: young men (28.8±12.6 seconds) and women (20.8±13.5 seconds), middle-aged men (17.0±8.5 seconds) and women (15.3±5.2 seconds), and older men (15.8±6.7 seconds) and women (17.9±8.1 seconds). The mean maximal lip strengths were: young men (11.6±3.0 kPa) and women (11.4±3.8 kPa), middle-aged men (11.4±4.2 kPa) and women (11.1±5.1 kPa), and older men (14.5±3.9 kPa) and women (11.7±2.6 kPa). The mean lip endurance scores were: young men (41.1±23.9 seconds) and women (22.4±21.7 seconds), middle-aged men (24.3±10.3 seconds) and women (30.5±13.4 seconds), and older men (24.9±11.0 seconds) and women (12.8±7.6 seconds). The mean maximal cheek strengths were: young men (24.5±4.6 kPa) and women (20.5±4.3 kPa), middle-aged men (25.2±6.4 kPa) and women (21.2±5.5 kPa), and older men (22.4±5.3 kPa) and women (18.0±4.8 kPa). The mean cheek endurance scores were: young men (47.8±24.4 seconds) and women (43.9±25.0 seconds), middle-aged men (27.3±11.3 seconds) and women (20.0±14.6 seconds), and older men (21.7±14.5 seconds) and women (17.2±11.4 seconds).

Conclusion

The data collected in this study will provide an important database of standardized measurements for maximal strength and endurance scores of the tongue, lip and cheek in healthy, normal Koreans.

Impact of appropriateness of empiric therapy on outcomes in community-onset bacteremia by extended-spectrum-β-lactamase producing Escherichia coli and Klebisella pneumoniae definitively treated with carbapenems

Despite a significant increase of bloodstream infection caused by extended-spectrum-β-lactamase (ESBL)-producing Enterobacteriaceae in the community-setting, information regarding clinical outcomes of inappropriate empiric therapy (IAT) in patients with those infections is limited. A multicenter-retrospective cohort study was conducted in four hospitals. A total of 249 adults were identified to have community-onset bacteremia caused by ESBL-producing Escherichia coli and Klebsiella pneumoniae, and definitively treated with carbapenems. According to the appropriateness of empiric therapy, individuals were divided into an appropriate empiric therapy (AT) group (n = 106) and IAT group (n = 143). Patients who received AT showed more severe underlying conditions including underlying solid cancer, healthcare-association and intensive care unit (ICU) care, compared to the IAT group. Primary bacteremia was more commonly found in the AT group than in the IAT group, while urinary tract infection predominated more frequently in the IAT group than in the AT group. Multivariate analysis using propensity score analysis indicated that inappropriateness of empiric therapy was not an independent risk factor for 30-day death. ICU care, respiratory tract infection and underlying liver, renal and connective tissue diseases were significantly associated with mortality. In patients with bloodstream infections caused by ESBL-producing E. coli and K. pneumoniae in the community-setting, delay in appropriate therapy was not associated with an increased rate of death if the patients were definitively treated with carbapenems.

Synthesis of O- and N-alkylated products of 1,2,3,4-tetrahydrobenzo[c][2,7]naphthyrin-5(6H)-one

Efficient syntheses of O- and N-alkylated products of 1,2,3,4-tetrahydrobenzo[c][2,7]naphthyrin-5(6H)-one are presented. The O-alkylated analogues were synthesized through a reduction-cyclization cascade and a selective O-alkylation reaction; whereas the N-alkylated analogues were obtained through a key Buchwald coupling.

Proteasome inhibitors with pyrazole scaffolds from structure-based virtual screening

We performed a virtual screen of ∼340 000 small molecules against the active site of proteasomes followed by in vitro assays and subsequent optimization, yielding a proteasome inhibitor with pyrazole scaffold. The pyrazole-scaffold compound displayed excellent metabolic stability and was highly effective in suppressing solid tumor growth in vivo. Furthermore, the effectiveness of this compound was not negatively impacted by resistance to bortezomib or carfilzomib.

A case-control study of brain structure and behavioral characteristics in 47,XXX syndrome

Trisomy X, the presence of an extra X chromosome in females (47,XXX), is a relatively common but under-recognized chromosomal disorder associated with characteristic cognitive and behavioral features of varying severity. The objective of this study was to determine whether there were neuroanatomical differences in girls with Trisomy X that could relate to cognitive and behavioral differences characteristic of the disorder during childhood and adolescence. MRI scans were obtained on 35 girls with Trisomy X (mean age 11.4, SD 5.5) and 70 age- and sex-matched healthy controls. Cognitive and behavioral testing was also performed. Trisomy X girls underwent a semi-structured psychiatric interview. Regional brain volumes and cortical thickness were compared between the two groups. Total brain volume was significantly decreased in subjects with Trisomy X, as were all regional volumes with the exception of parietal gray matter. Differences in cortical thickness had a mixed pattern. The subjects with Trisomy X had thicker cortex in bilateral medial prefrontal cortex and right medial temporal lobe, but decreased cortical thickness in both lateral temporal lobes. The most common psychiatric disorders present in this sample of Trisomy X girls included anxiety disorders (40%), attention-deficit disorder (17%) and depressive disorders (11%). The most strongly affected brain regions are consistent with phenotypic characteristics such as language delay, poor executive function and heightened anxiety previously described in population-based studies of Trisomy X and also found in our sample.

Abstract 1808: Potentiation of proteasome inhibitor cytotoxicity by co-treatment with novel β1i-selective immunoproteasome inhibitors

The FDA-approved proteasome inhibitors bortezomib and carfilzomib have contributed to major improvements in the treatment of multiple myeloma (MM) following their adoption as key therapies over the last 10 years. Despite the sucesses of proteasome inhibitor-based cancer therapies, drug resistance as well as dose-limiting adverse events remain problematic and prevent these agents from devliering durable and complete responses. Our prior research indicated that unlike carfilzomib and bortezomib which inhibit both the β5 and β5i subunits of the proteasome and immunoproteasome, β1i-selective inhibitors are not cytotoxic. Based on an understanding of the functional role of the β1i in cancer cells, we hypothesized that simulatenous administration of a non-toxic β1i inhibitor would potentiate the activity of classic proteasome inhibitors such as bortezomib and carfilzomib. By developing novel peptide epoxyketones with improved selectivity for β1i, we sucessfully demonstrated that such inhibitors are both non-toxic and are capable of potentiating the activity of cytotoxic proteasome inhibitors via β1i-dependent mechanisms. In the future, the co-administration of β1i-targeting agents and cytotoxic proteasome inhibitors, or the administration of novel agents which potently target β5, β5i, and β1i may serve as therapies for multiple myeloma and other cancers with greater efficacy, safety, and tolerabiliy than existing proteasome inhibitor-based therapies.

In order to study this potentiating effect, we began by creating analogs of a known β1i-inhibiting tetrapeptide epoxyketone with modest selectivity for β1i over β1. Approximately twenty tetrapeptide and tripeptide epoxyketones were synthesized and evaluated for their activity against multiple proteasome subunits using subunit-selective flurogenic substrates in the presence of purified 20S proteasomes. Several promising analogs were identified and evaluted in cell culture with human MM cell lines including a carfilzozmib-resistant variant of the RPMI 8226 cell line. Cell viability following treatment with various classic and β1i-targeting proteasome inhibitors was evaluated via MTS assay.

In summary, several peptide epoxyketones with improved potency against β1i or improved selectivity over β1 were identified. These inhibitors sucessfully inhibited proteasome catalytic activity both in vitro using purified proteasomes as well as in live cells in culture. Despite being non-toxic when administered alone, β1i-selective agents significantly decreased cell viability when combined with sub-IC50 concentrations of cytoxic proteasome inhibitors. Additionally, this potentiating effect was retained in a carfilzomib-resistant human MM cell line.

Citation Format: Zachary C. Miller, Ying Wu, Na-Ra Lee, Shuo Zhou, Kyung-Bo Kim. Potentiation of proteasome inhibitor cytotoxicity by co-treatment with novel β1i-selective immunoproteasome inhibitors. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1808. doi:10.1158/1538-7445.AM2014-1808

Use of pupil size to determine the effect of electromagnetic acupuncture on activation level of the autonomic nervous system

Magnetic fields are widely considered as a method of treatment to increase the therapeutic effect when applied to acupoints. Hence, this study proposes a new method which creates significant stimulation of acupoints by using weak magnetic fields. We conducted this experiment in order to confirm the effect on the activation level of the autonomic nervous system by measuring pupil sizes in cases of stimulation by using manual acupuncture and electromagnetic acupuncture (EMA) at BL15. We selected 30 Hz of biphasic wave form with 570.1 Gauss. To confirm the biopotential by the magnetic flux density occurring in EMA that affected the activation of the autonomic nervous system, we observed the biopotential induced at the upper and the mid left and right trapezius. We observed a significant decrease in pupil size only in the EMA group (p < 0.05), thus confirming that EMA decreased the pupil size through activation of the parasympathetic nerve in the autonomic nervous system. Moreover, we confirmed that the amplitude of the biopotential which was caused by 570.1 Gauss was higher than ±20 μA. Thus, we can conclude that EMA treatment successfully activates the parasympathetic nerve in the autonomic nervous system by inducing a biotransformation by the induced biopotential.

Abstract 1021: The development of non-covalent non-peptide inhibitors of the proteasome: exploring a series of proteasome-inhibiting pyrazoles

The purpose of this study was to develop reversible, non-peptide, non-covalent inhibitors of the 20S proteasome. The FDA approval of the peptide-based proteasome inhibitors bortezomib and carfilzomib in 2003 and 2012, respectively, has validated the proteasome as an important target in the treatment of multiple myeloma. Additionally, these inhibitors have demonstrated in vitro as well moderate in vivo efficacy in preclinical models of solid tumors. Despite this, clinical trials utilizing these drugs for the treatment of solid tumors have shown disappointing results. Although the reasons for these failures remain unclear, one possibility is that existing proteasome inhibitors such as bortezomib and carfilzomib lack the pharmacokinetic and pharmacodynamic properties needed to sufficiently inhibit proteasomes in solid tumors . With this in mind, it has been postulated that reversible, non-peptide proteasome inhibitors could be developed with improved properties and that these inhibitors could serve both as novel tools to advance our understanding of the proteasome and as potential therapeutic options for the treatment of solid tumors. In order to identify novel proteasome inhibitors with non-peptide scaffolds, we conducted an in silico screen of more than 340,000 structures followed by in vitro assays using purified proteasomes. This screening effort lead to several novel non-peptide hits. One hit, a substituted pyrazole derivative, was used as the lead compound to synthesize a small library of analogs. These compounds were evaluated for their ability to inhibit proteasome catalytic activity using specific fluorogenic substrates and a structure-activity relationship was developed. In vitro cell viability assays were conducted against three non-small cell lung cancer (NSCLC) cell lines. The in vivo antitumor activity of the most promising analog was also determined using a NSCLC xenograph model. Our lead compound was found to have reversible inhibitory activity against the chymotrypsin-like subunits of the 20S proteasome and immunoproteasome with single-micromolar IC50 values. We found that our lead compound was equipotent against three NSCLC cell lines despite varied sensitivity to bortezomib and carfilzomib. IC50 values against these cell lines were less than 10 μM. Using an analog with improved potency and promising drug-like properties, inhibition of in vivo tumor growth was also observed. Studies designed to validate the proteasome as the target of this series of compounds are ongoing.

Citation Format: Zachary C. Miller, Do-Min Lee, Na-Ra Lee, Kyungbo Kim, Wooin Lee, Kyung Bo Kim. The development of non-covalent non-peptide inhibitors of the proteasome: exploring a series of proteasome-inhibiting pyrazoles. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1021. doi:10.1158/1538-7445.AM2013-1021

Development and evaluation of a multi-frequency bioelectrical impedance analysis analyzer for estimating acupoint composition

The purpose of this study was to suggest a new method of estimating acupoint compositions by using a multi-frequency bioelectrical impedance analysis (MF-BIA) method at 5 kHz, 50 kHz and 200 kHz within 2 cm of acupoints divided into local segments. To verify the system developed, we confirmed the stable occurrence of a constant current at every frequency, regardless of the impedance connected to the electrodes. Moreover, we found left and right distal bicep brachii aponeurosis to be identical by using ultrasound imaging, and we analyzed the repeatability of the findings by making 10 consecutive sets of measurements (p > 0.05). To evaluate the practical use of the acupoint composition, we used the MF-BIA analyzer to measure the left and right LU3, LU4, and LU9 at the lung meridian. We confirmed that the potentials generated were equal to the changes in the cell membrane function, which were caused by the applied frequency (p < 0.01). We also verified that the MF-BIA analyzer measurements corresponded to the acupoint components by comparing the left and right potentials generated (p > 0.05). Hence, we conclude that the MF-BIA analyzer can be used to estimate the acupoint composition based on the acupoint state.

Comparison of 2 methods of non-invasive treatment between transcutaneous electrical stimulation and pulsed electromagnetic field stimulation as replacement of invasive manual acupuncture

The aim of this study was to find the non-invasive optimal alternative method for Manual Acupuncture. Existing researches had reported that Transcutaneous Electrical Acupoint Stimulation (TEAS) was an effective treatment method instead of manual acupuncture. In place of the TEAS, we suggested the Pulsed Electromagnetic Fields (PEMFs). Thus, we designed the PEMFs system which can stimulate only an acupoint. There have been no researches which reported therapeutic effect when stimulating at an identical acupoint by TEAS and PEMFs. Hence, this study investigated the therapeutic effect on the muscle fatigue after the strenuous knee extension/flexion exercise by two stimulations. We selected the stimulation method of both TEAS and PEMFs by using 2Hz biphasic rectangular wave pulse and pulse width 0.2ms. The magnetic flux was the 30.92mT (309.2gauss) at 2 Hz. The electromyogram (EMG) and the maximal voluntary contraction (MVC) at rectus femoris were measured. The Median Frequency (MF) at TEAS group was significantly effective at 6 minutes (p=0.499). The PEMFs group was recovered to the MF rapidly after 4 minutes (p=0.166). The results of the peak torque indicated that both non-stimulation group and TEAS group did not recover to the peak torque at pre-exercise during the recovery period (p<0.05). In contrast, the significant treatment effect of PEMFs group was found after 14 minutes (p=0.135). The results of this study demonstrated that PEMFs were better than TEAS as a non-invasive method to replace the manual acupuncture.

Activity-based near-infrared fluorescent probe for LMP7: a chemical proteomics tool for the immunoproteasome in living cells

Probing the unknown: The immunoproteasome, an alternative form of the constitutive proteasome, has been implicated in a number of pathological states such as cancer and autoimmune diseases. In an effort to understand the role of the immunoproteasome in cells, the first immunoproteasome-specific near-infrared fluorescent probe has been developed.

Revisiting the role of the immunoproteasome in the activation of the canonical NF-κB pathway

The discovery of NF-κB signaling pathways has greatly enhanced our understanding of inflammatory and immune responses. In the canonical NF-κB pathway, the proteasomal degradation of IκBα, an inhibitory protein of NF-κB, is widely accepted to be a key regulatory step. However, contradictory findings have been reported as to whether the immunoproteasome plays an obligatory role in the degradation of IκBα and activation of the canonical NF-κB pathway. Such results were obtained mainly using traditional gene deletion strategies. Here, we have revisited the involvement of the immunoproteasome in the canonical NF-κB pathway using small molecule inhibitors of the immunoproteasome, namely UK-101 and LKS01 targeting β1i and β5i, respectively. H23 and Panc-1 cancer cells were pretreated with UK-101, LKS01 or epoxomicin (a prototypic inhibitor targeting both the constitutive proteasome and immunoproteasome). We then examined whether these pretreatments lead to any defect in activating the canonical NF-κB pathway following TNFα exposure by monitoring the phosphorylation and degradation of IκBα, nuclear translocation of NF-κB proteins and DNA binding and transcriptional activity of NF-κB. Our results consistently indicated that there is no defect in activating the canonical NF-κB pathway following selective inhibition of the immunoproteasome catalytic subunits β1i, β5i or both using UK-101 and LKS01, in contrast to epoxomicin. In summary, our current results using chemical genetic approaches strongly support that the catalytic activity of the immunoproteasome subunits β1i and β5i is not required for canonical NF-κB activation in lung and pancreatic adenocarcinoma cell line models.

Abstract 4744: Development of an immunoproteasome fluorescent substrate: A functional proteomics tool

Introduction: This research was conducted to develop the first immunoproteasome fluorescent substrate. The immunoproteasome is an alternate form of the constitutive proteasome with distinct catalytic subunits. While immunoproteasomes appear to generate peptides for MHC class I antigen presentation, their functions are still not completely understood. Antibody-based studies have shown that immunoproteasome catalytic subunits are expressed in a variety of cancers, suggesting they may play important roles in this disease. However, antibodies bind both active and inactive subunits, rendering these studies incapable of correlating immunoproteasome activity with disease progression. Although fluorescent peptide substrates are widely used to monitor proteasome activity, those currently available are cleaved by both forms of the proteasome. Therefore, fluorescent substrates selectively cleaved by the immunoproteasome are needed to correlate their activity with cancer progression. Experimental Procedures: The fluorescent substrate was synthesized by replacing the epoxyketone pharmacophore of the immunoproteasome-selective inhibitor YU-102 with a 7-amino-4-methylcoumarin (AMC) fluorogenic moiety. The rates of hydrolysis of the resulting substrate, YU-102-AMC, by both purified constitutive proteasomes and immunoproteasomes were evaluated by monitoring the release of AMC over time. Hydrolysis of this substrate was also investigated in T1 and T2 cell lysates. Data Summary: The structure of the fluorescent substrate YU-102-AMC was confirmed by mass spectrometry and nuclear magnetic resonance spectroscopy. YU-102-AMC was preferentially cleaved by purified immunoproteasomes in comparison with purified constitutive proteasomes. This preferential cleavage by immunoproteasomes was confirmed in lysates of cancer cell lines T1 and T2. Conclusions: We have successfully developed YU-102-AMC, an immunoproteasome fluorescent substrate which facilitates quantification of immunoproteasome activity in cancer cell lysates. This substrate will be utilized to examine a correlation between immunoproteasome activity and cancer progression.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4744. doi:1538-7445.AM2012-4744

A bright approach to the immunoproteasome: development of LMP2/β1i-specific imaging probes

While the constitutive, 26S proteasome plays an important role in regulating many important cellular processes, a variant form known as the immunoproteasome is thought to primarily function in adaptive immune responses. However, recent studies indicate an association of immunoproteasomes with many physiological disorders such as cancer, neurodegenerative, and inflammatory diseases. Despite this, the detailed functions of the immunoproteasome remain poorly understood. Immunoproteasome-specific probes are essential to gain insight into immunoproteasome function. Here, we describe for the first time the development of cell-permeable activity-based fluorescent probes, UK101-Fluor and UK101-B660, which selectively target the catalytically active LMP2/β1i subunit of the immunoproteasome. These probes facilitate rapid detection of the cellular localization of catalytically active immunoproteasomes in living cells, providing a valuable tool to analyze immunoproteasome functions. Additionally, as LMP2/β1i may serve as a potential tumor biomarker, an LMP2/β1i-targeting fluorescent imaging probe may be applicable to a rapid readout assay to determine tumor LMP2/β1i levels.

Abstract 2621: Development of Fluoro-UK-101, an immunoproteasome-targeting activity-based fluorescent probe

Introduction: This study was conducted to develop the first activity-based fluorescent probe targeting the immunoproteasome subunit LMP2. The immunoproteasome is an alternate form of the constitutive proteasome which is composed of unique catalytic subunits. While immunoproteasomes were believed to primarily function in generating peptides for antigen presentation on MHC class I molecules, antibody-based studies have revealed the expression of immunoproteasome catalytic subunits in a variety of cancers. However, antibodies are incapable of distinguishing between active and inactive forms of these proteins, a limitation that can be overcome using activity-based probes.

Experimental Procedures: Fluorescent compounds were synthesized by derivatization of the LMP2-specific inhibitor UK-101 at the P2 position, where lysine was substituted for alanine. The free amino group on the side chain of lysine was coupled to linkers of various lengths. Fluorescein was then coupled to each linker to yield the fluorescent probes. These compounds were characterized in prostate cancer cell lines via sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and immunofluorescence (IF) microscopy. One analog was selected for further characterization. Prostate cancer cells were treated with an LMP2-selective dose of this analog, Fluoro-UK-101, and the co-localization of this fluorescent probe with antibodies specific for proteasome subunits and intracellular organelles was examined via IF.

Data Summary: The structures of the synthesized fluorescent derivatives of UK-101 were confirmed via mass spectrometry and nuclear magnetic resonance spectroscopy. Treatment of prostate cancer cells with these compounds gave punctate staining in a dose-dependent manner, indicating the cell permeability and activity of these probes. The impact of the linker length on LMP2 binding specificity and fluorescent signal strength was determined via SDS-PAGE and IF microscopy. Doses at which these fluorescent analogs specifically target LMP2, but not other proteasome subunits, were identified via SDS-PAGE. One analog, Fluoro-UK-101, was selected based on binding specificity and IF intensity. Additionally, IF microscopy techniques using the selected fluorescent analog, Fluoro-UK-101, revealed differences in LMP2 localization patterns among prostate cancer cell lines.

Conclusions: We have successfully developed Fluoro-UK-101, an activity-based fluorescent probe that selectively binds the immunoproteasome catalytic subunit LMP2. Fluoro-UK-101 allows the visualization of catalytically active immunoproteasomes in intact cells. Modification of the fluorophore will facilitate its application in a rapid readout assay to detect tumors in animal models using LMP2 as a biomarker.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2621. doi:10.1158/1538-7445.AM2011-2621

Cooperative translocation enhances the unwinding of duplex DNA by SARS coronavirus helicase nsP13

SARS coronavirus encodes non-structural protein 13 (nsP13), a nucleic acid helicase/NTPase belonging to superfamily 1 helicase, which efficiently unwinds both partial-duplex RNA and DNA. In this study, unwinding of DNA substrates that had different duplex lengths and 5'-overhangs was examined under single-turnover reaction conditions in the presence of excess enzyme. The amount of DNA unwound decreased significantly as the length of the duplex increased, indicating a poor in vitro processivity. However, the quantity of duplex DNA unwound increased as the length of the single-stranded 5'-tail increased for the 50-bp duplex. This enhanced processivity was also observed for duplex DNA that had a longer single-stranded gap in between. These results demonstrate that nsP13 requires the presence of a long 5'-overhang to unwind longer DNA duplexes. In addition, enhanced DNA unwinding was observed for gapped DNA substrates that had a 5'-overhang, indicating that the translocated nsP13 molecules pile up and the preceding helicase facilitate DNA unwinding. Together with the propensity of oligomer formation of nsP13 molecules, we propose that the cooperative translocation by the functionally interacting oligomers of the helicase molecules loaded onto the 5'-overhang account for the observed enhanced processivity of DNA unwinding.

Investigation of the pharmacophore space of Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) NTPase/helicase by dihydroxychromone derivatives

Aryl diketoacids have been identified as the first SARS-CoV NTPase/helicase inhibitors with a distinct pharmacophore featuring an arylmethyl group attached to a diketoacid. In order to search for the pharmacophore space around the diketoacid core, three classes of dihydroxychromone derivatives were prepared. Based on SAR study, an extended feature of the pharmacophore model of SARS-CoV NTPase/helicase was proposed which is constituted of a diketoacid core, a hydrophobic arylmethyl substituent, and a free catechol unit.

Effects of substrates on biofilm formation observed by atomic force microscopy

Formation of biofilm is known to be strongly dependent on substrates including topography, materials, and chemical treatment. In this study, a variety of substrates are tested for understanding biofilm formation. Sheets of aluminum, steel, rubber, and polypropylene have been used to examine their effects on formation of Pseudomonas aeruginosa biofilm. In particular, the morphological variation, transition, and adhesiveness of biofilm were investigated through local measurement by atomic force microscopy (AFM). Mechanism of removing biofilm from adhering to substrate is also analyzed, thus the understanding of the mechanism can be potentially useful to prevent the biofilm formation. The results reveal that formation of biofilm can remain on rough surface regardless of substrates in hot water, which may easily induce extra-polymeric substances detachment from bacterial surface. By probing using AFM, local force-distance characterization of extra-cellular materials extracted from the bacteria can exhibit the progress of the biofilm formation and functional complexities.

Aryl diketoacids (ADK) selectively inhibit duplex DNA-unwinding activity of SARS coronavirus NTPase/helicase

As anti-HCV aryl diketoacids (ADK) are good metal chelators, we anticipated that ADKs might serve as potential inhibitors of SARS CoV (SCV) NTPase/helicase (Hel) by mimicking the binding modes of the bismuth complexes which effectively competes for the Zn(2+) ion binding sites in SCV Hel thereby disrupting and inhibiting both the NTPase and helicase activities. Phosphate release assay and FRET-based assay of the ADK analogues showed that the ADKs selectively inhibit the duplex DNA-unwinding activity without significant impact on the helicase ATPase activity. Also, antiviral activities of the ADKs were shown dependent upon the substituent. Taken together, these results suggest that there might be ADK-specific binding site in the SCV Hel, which warrants further investigations with diverse ADKs to provide valuable insights into rational design of specific SCV Hel inhibitors.

Cloning and sequence analyses of a 2,3-dihydroxybiphenyl 1,2-dioxygenase gene ( bphC) from Comamonas sp. SMN4 for phylogenetic and structural analysis

A genomic library of biphenyl-degrading Comamonas sp. SMN4 for isolating fragments containing the 2,3-dihydroxybiphenyl 1,2-dioxygenase (23DBDO) gene was constructed. The smallest subclone (pNPX9) encoding 23DBDO activity was sequenced and analyzed. The C-terminal domain of 23DBDO from Comamonas sp. SMN4 had five catalytically essential residues and was more highly conserved than the N-terminal domain. Phylogenetic and structural relationships of 23DBDO from Comamonas sp. SMN4 were analyzed.

Molecular cloning of the nahG gene encoding salicylate hydroxylase from Pseudomonas fluorescens

A gene encoding the salicylate hydroxylase was cloned from the genomic DNA of Pseudomonas fluorescens SME11. The DNA fragment containing the nahG gene for the salicylate hydroxylase was mapped with restriction endonucleases and sequenced. The DNA fragment contained an ORF of 1,305 bp encoding a polypeptide of 434 amino acid residues. The nucleotide and amino acid sequences of the salicylate hydroxylase revealed several conserved regions with those of the enzyme encoded in P. putida PpG7: The homology of the nucleotide sequence is 83% and that of amino acid sequence is 72%. We found large conserved regions of the amino acid sequence at FAD and NADH binding regions. The FAD binding site is located at the amino terminal region and a lysine residue functions as a NADH-binding site.

Helicobacter pylori in dental plaque and saliva

BACKGROUND

About half of the world population is infected with H. pylori, but the transmission and the source of this infection are still unclear. Recently, dental plaque (DP) and saliva have been implicated as possible sources of H. pylori infection. This study was done to investigate the detection rates of H. pylori in the DP and saliva by use of PCR depending on H. pylori infection state of gastric mucosa.

METHODS

In 46 subjects, gastric H. pylori colonization was evaluated with CLO test, microscopy of Gram stained mucosal smear, culture and histology after modified Giemsa staining in the antrum and body, respectively. A patient was regarded as H. pylori positive if one or more of the four aforementioned test methods demonstrated H. pylori colonization of the gastric mucosa. For detection of H. pylori in the DP and saliva, PCR assay was done with ET4-U and ET4-L primers. To estimate the sensitivity and specificity of this PCR, H. pylori positivity was evaluated in the antrum and body, separately.

RESULTS

The sensitivity of mucosal PCR was 50.0% (27/54) and the specificity 86.8% (33/38). When a subject was regarded as H. pyloi positive, if either antrum or body mucosal H. pylori was is positive, the positive rate of mucosal PCR was 62.1% (18 subjects) in the 29 H. pylori-positive and 17.6% (3 subjects) in the 17 H. pylori-negative subjects. DP PCR was positive in 2 of 29 H. pylori-positive subjects (6.9%) and none in the 17 H. pylori-negative (0%). Saliva PCR was positive in 4 of 14 H. pylori-positive subjects (28.6%) and none of 6 H. pylori-negative (0%).

CONCLUSION

The detection rates of H. pylori in DP and saliva by PCR were rather low, 6.9% and 28.6%, respectively, and these rates might have been underestimated by low sensitivity of the PCR method used in this study. However, the results that H. pylori was found in the DP and saliva suggest that the oral cavity can perform a role as a reservoir of H. pylori in Korea.

Staged surgical treatment of obstructive sleep apnea syndrome: a review of 35 patients

PURPOSE

The purpose of this study was to investigate the success of a staged surgical reconstruction of the upper airway for treatment of obstructive sleep apnea syndrome.

PATIENTS AND METHODS

Thirty-five patients with obstructive sleep apnea syndrome documented by nocturnal polysomnography were treated surgically with a staged protocol for reconstruction of the upper airway. All patients were evaluated preoperatively by a history and physical examination, including fiberoptic nasopharyngoscopy, oropharyngoscopy, and hypopharyngoscopy; cephalometric analysis; and laboratory polysomnography. All patients included were diagnosed with type II obstruction, with collapse at the oropharyngeal and hypopharyngeal levels. Stage I reconstruction consisted of uvulopalatopharyngoplasty (UPPP) by the Fujita method and anterior mandibular osteotomy (AMO) or inferior sagittal osteotomy (ISO) with genioglossus muscle advancement. If stage I was unsuccessful, patients were advanced to stage II and stage III, if necessary. Stage II reconstruction consisted of bimaxillary advancement with rigid fixation. Stage III reconstruction consisted of hyoid myotomy and advancement.

RESULTS

All patients underwent follow-up nocturnal polysomnography 4 to 6 months after the last surgical procedure. Most patients responded positively to stage I reconstruction (respiratory disturbance index [RDI] < 20, with O2 saturation 95+%). Twenty-four patients (69%) had postoperative RDIs of 20 or less. Of these, 11 patients (31%) had an RDI of five or fewer; seven patients (20%) had an RDI between 6 and 10, and six patients (17%) had an RDI between 10 and 20. The mean preoperative RDI was 53, and the mean postoperative RDI was 19. Of the three patients who elected to proceed to stage II reconstruction, all had a postoperative RDI of 10 or less (two patients [67%] had an RDI of 5 or less, and one patient [33%] had an RDI of 6 to 10).

CONCLUSION

This study showed that properly selected patients with obstructive sleep apnea syndrome benefit from a staged reconstruction of the upper airway.

A null mutation in the photoreceptor guanylate cyclase gene causes the retinal degeneration chicken phenotype

The retinas of the retinal degeneration (rd) chicken are fully developed and possess normal morphology at hatching but fail to respond to light stimulation. Analyses of retinal cGMP, the internal messenger of phototransduction, show that the amount of cGMP in predegenerate, fully developed rd/rd photoreceptors is 5-10 times less than that seen in normal photoreceptor cells. We show that the low levels of cGMP in rd chicken retina are a consequence of a null mutation in the photoreceptor guanylate cyclase (GC1) gene. Thus, the rd chicken is a model for human Leber's congenital amaurosis. Absence of GC1 in rd retina prevents phototransduction and affects survival of rods and cones but does not interfere with normal photoreceptor development.

Enhancing mammography referral in primary care

BACKGROUND

This 1-year randomized trial tested the efficacy of behavioral techniques for increasing mammography referrals by primary care physicians in small, community practices.

METHODS

Sixty-one practices were randomly assigned to one of three conditions: (1) education-only control, (2) education plus cue enhancement using mammography chart stickers, and (3) education plus cue enhancement plus feedback and token rewards. Quarterly chart audits of a defined sample (N = 11,716) of women patients 50 years of age or older were conducted to document mammography referrals, completions, and compliance.

RESULTS

Referral and completion rates increased from baseline to first quarter and gradually declined thereafter. Overall, these rates were higher in the cuing conditions than in the control condition. In contrast, compliance rates in both experimental conditions increased over the year while remaining static in the control condition, demonstrating a strong and continuing effect for cue enhancement. Compliance increases were greatest for physicians who were older, nonwhite, with a second speciality, in solo practice, not members of the AMA, not residency trained, and not board certified.

CONCLUSIONS

Chart stickers can significantly increase mammography utilization in small, community practices. These practices are an efficient route to reaching large numbers of older women in need of mammography screening.

Physical structure and expression of alkBA encoding alkane hydroxylase and rubredoxin reductase from Pseudomonas maltophilia

The structural genes of the Pseudomonas maltophilia alk system, which are localized on the OCT plasmid were cloned as a 4.2-kilobase pair Hind III fragment. This fragment contains sequences for alkane hydroxylase gene (alkB) and rubredoxin reductase gene (alkA), respectively. The alkB gene encodes a 373-amino acid polypeptide (47.4 kD) that can be expressed at high levels in Pseudomonas and Escherichia coli. The alkBA genes were complemented with alkane hydroxylation in both bacteria. This result shows that alkBA gene is essential for alkane hydroxylation since chromosomal loci have been encoded for other enzymes involved in fatty acid oxidation.

Properties of clock-controlled and constitutive N-acetyltransferases from chick pineal cells

The pineal gland synthesizes its hormone melatonin (O-methyl-N-acetylserotonin) from serotonin. Acetyl-CoA: serotonin N-acetyltransferase (SNAT), the enzyme that catalyzes the committed step in this biosynthesis, is largely restricted to the pineal gland and is regulated by adrenergic and circadian mechanisms. Another enzyme, acetyl-CoA: arylamine N-acetyltransferase (ANAT), having an apparently similar activity, is also present in the pineal. This enzyme, however, is not rhythmically regulated. SNAT activity of cultured chick pineal cells was obtained without ANAT after ammonium sulfate precipitation. ANAT activity was retained without SNAT activity after pre-incubation at 37 degrees C. Thus, each enzyme could be examined independently. Overlap in substrate specificity between the two enzymes was minimal. Kinetic analysis of the separated enzyme activities revealed that while SNAT operates via a random or ordered bi bi mechanism, ANAT catalysis occurs through a ping pong bi bi mechanism with substrate inhibition by acetyl-CoA. By size-exclusion chromatography, ANAT was confirmed to be 30-35 kDa, and SNAT was estimated at 15-20 kDa. Taken together, these results indicate that the two enzymes differ in their structure, reactivity, stability, and mechanism of catalysis.

The impact of Hurricane Hugo and the San Francisco earthquake on a sample of people with rheumatoid arthritis

The health effects of two natural disasters on 32 people with rheumatoid arthritis (RA) were assessed during the second-year wave of interviews in an ongoing 3-year study. Although the severity of Hurricane Hugo exceeded that of the San Francisco earthquake, no significant differences in health impacts were found. Both groups reported significantly increased ratings of RA activity, pain, and depression compared with ratings during the first year. However, comparison with the rest of the sample (n = 767) showed that increases in disease activity and pain were a general phenomenon but that the increase in depression was unique to the disaster subsample. Physician health status assessments also indicated that those who experienced the disaster were more likely to be classified in later stages of the disease subsequent to the disaster and were more likely to experience flares. These results suggest that people with RA may constitute a special high-risk population for adverse health effects after natural disasters.

Evaluation of rebreathing in various modifications of the Mapleson-D system

Several modifications of the Bain system for nitrous oxide analgesia or general anesthesia were tested for rebreathing and retention of CO2. The classic Bain circuit causes the most rebreathing as measured by the fractional concentration of CO2 in a sample of inspired gas (FICO2), but stimulation of the respiratory system seems to allow near normal end tidal CO2 and arterial CO2 tensions. The most predictable systems that have the least amount of rebreathing are those that have the least dead space.

Carbon dioxide absorption system with a simple modification of the Bain circuit

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