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Understanding the mechanisms of amyloid formation and toxicity remain major challenges. Although substantial progress has been made in the development of methods able to identify the species formed during self-assembly and to describe the kinetic mechanisms of aggregation, the structure(s) of non-native species, including potentially toxic oligomers, remain elusive. Moreover, how fibrils contribute to disease remains unclear. Here we review recent advances in the development of small molecules and other reagents that are helping to define the mechanisms of protein aggregation in molecular detail. Such probes form a powerful platform with which to better define the mechanisms of structural conversion into amyloid fibrils and may provide the much-needed stepping stone for future development of successful therapeutic agents., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Although amyloid assembly in vitro is commonly investigated using single protein sequences, fibril formation in vivo can be more heterogeneous, involving co-assembly of proteins of different length, sequence and/or post-translational modifications. Emerging evidence suggests that co-polymerization can alter the rate and/or mechanism of aggregation and can contribute to pathogenicity. Electrospray ionization-ion mobility spectrometry-mass spectrometry (ESI-IMS-MS) is uniquely suited to the study of these heterogeneous ensembles. Here, ESI-IMS-MS combined with analysis of fibrillation rates using thioflavin T (ThT) fluorescence, is used to track the course of aggregation of variants of islet-amyloid polypeptide (IAPP) in isolation and in pairwise mixtures. We identify a sub-population of extended monomers as the key precursors of amyloid assembly, and reveal that the fastest aggregating sequence in peptide mixtures determines the lag time of fibrillation, despite being unable to cross-seed polymerization. The results demonstrate that co-polymerization of IAPP sequences radically alters the rate of amyloid assembly by altering the conformational properties of the mixed oligomers that form.

Background: A spot-on spinetoram formulation (Cheristin ® ) was developed to eliminate fleas from infested cats. This paper describes three spinetoram studies: two for registration (Studies 1 and 2), and one comparing residual speed of kill (SOK) with topically applied fipronil/(S)-methoprene (FSM) and imidacloprid (Study 3)., Methods: Cats were randomized to treatment based on flea counts from infestations placed within 2 weeks prior to treatment. In Studies 1 and 2, groups were untreated control and spinetoram; in Study 3, groups were untreated control, spinetoram, FSM and imidacloprid, all applied per label on Day 0. Cats were infested the day before treatment. In Studies 1 and 2, counts were completed 48 h post-treatment and after weekly challenges through 5 weeks. In Study 3, infestations were completed weekly through Day 28, with counts 1, 4, 8 and 12 h after treatment or post-infestation (PI). Efficacy was determined on geometric mean flea count reductions compared with controls, and in Study 3 mean flea counts in spinetoram-groups were compared with those in FSM and imidacloprid groups., Results: In Studies 1 and 2, spinetoram effectiveness was 100% against existing infestations, and at least 96% through Day 37. In Study 3 mean counts were not significantly different from controls in any group until 8 h post-treatment when imidacloprid counts were significantly lower than spinetoram counts, which were in turn significantly lower than FSM counts (P < 0.05). At 1 h PI spinetoram-group counts were significantly lower (P < 0.05) than counts in: controls, all days; imidacloprid, Days 7, 14, and 28; FSM, Days 14 and 28. At 4 h PI, spinetoram mean counts were significantly lower (P < 0.05) relative to: controls, all days; imidacloprid, Days 7, 14 and 21; FSM, Days 7, 14, 21 and 28 (P < 0.05). On multiple occasions, at 8 and 12 h PI, mean counts were significantly lower (P < 0.05) for spinetoram than for imidacloprid and FSM; at no point were FSM or imidacloprid significantly more effective than spinetoram against new infestations. All treatments were well tolerated., Conclusions: Spinetoram was highly effective for at least 1 month post-treatment and provided more rapid month-long residual SOK than FSM or imidacloprid.

Context: At the request of the National Wrestling Coaches Association and the head wrestling coach at our university, we conducted a study of infection transmission in collegiate wrestlers., Objective: To examine disinfectant effectiveness and develop best-practice guidelines for minimizing the spread of skin infections via wrestling mats., Design: Controlled laboratory study and crossover study., Setting: Laboratory and two 15-college wrestling invitational meets., Patients or Other Participants: A total of 231 collegiate wrestlers and 8 officials., Intervention(s): In the laboratory-based part of the study, we measured the bacterial load of mats disinfected with 10% bleach, OxiTitan, Benefect, eWater, and KenClean and inoculated with Staphylococcus epidermidis (strain ATCC 12228) at a concentration of 6.5 × 10 4 bacteria/cm 2 . In the empirical part of the study, we used these disinfectants during 2 invitational meets and measured mat and participant bacterial load during competition. Participants were swabbed at weigh-in and after their last bout. Mat bacterial load was monitored hourly., Main Outcome Measure(s): We determined total colony counts and species., Results: With controlled testing, we observed that products claiming to have residual activity reduced bacterial load by 63% over the course of competition compared with nonresidual agents. Only 4 of 182 participating wrestlers tested positive for methicillin-resistant Staphylococcus aureus , which is the normal population occurrence. The predominant species on mats were skin bacteria ( Staphylococcus epidermidis ) and substantial levels of respiratory bacteria ( Streptococcus pneumoniae ), as well as several soil species and a surprisingly low incidence of fecal bacteria ( Escherichia coli ). Disinfectant effectiveness during the meets was consistent with controlled study findings. Cleaning mats with residual disinfectants reduced the average bacterial load by 76% compared with nonresidual cleaners. Using a footbath did not reduce the bacterial load compared with a bleach-cleaned mat, but using alcohol-based hand gel reduced it by 78%., Conclusions: Best practices based on these data include backward mopping of the mats with a residual disinfectant pulled behind the cleaner, allowing mats to dry before walking on them, having wrestlers use hand gel before each bout, and strongly recommending that all wrestlers receive annual influenza vaccinations.

Background and Objective: Ethnicity is strongly associated with variable clinical presentation in sarcoidosis but the association between ethnicity and clinical characteristics has not previously been described in patients of Polynesian ancestry, Maori and Pacific Islander (PI). The objective of this study was to describe the clinical characteristics of sarcoidosis in Maori and PI patients and determine if those were different to European patients., Methods: A retrospective review of the medical records of 406 patients (69 Maori/PI) attending a specialist interstitial lung disease (ILD) clinic., Results: The population (207 females, mean age at presentation: 36) reflected the current New Zealand census data (2013) with only people of Indian ethnicity over-represented. Parenchymal lung involvement was uncommon in Maori and PI patients (21% Scadding stage 2, 2% stage 3), and no patient had extensive pulmonary fibrosis (stage 4). Computed tomography (CT) patterns of sarcoid parenchymal lung involvement were less commonly reported for Maori/PI. There were no differences in respect of baseline lung function or requirement for treatment. Ocular and skin involvement occurred more frequently in Maori and PI (P = 0.0045, P = 0.03), and erythema nodosum was more common in Caucasians (P = 0.0008)., Conclusion: People of Polynesian ancestry appear to have less pulmonary and more extra-pulmonary manifestations of sarcoidosis. This adds to our knowledge that sarcoidosis heterogeneity is influenced by ethnicity., (© 2016 Asian Pacific Society of Respirology.)

Purpose: To assess current cigarette, hookah, and electronic cigarette (e-cigarette) use among high school students with and without asthma. Beliefs and use of tobacco products by a household member were also examined., Methods: The 2014 Florida Youth Tobacco Survey was administered to high school students to assess current use of cigarettes, hookah, and e-cigarettes (i.e., within past 30 days). Student's home exposure and beliefs about cigarettes, hookah, and e-cigarettes were also assessed. Students were randomly selected using a two-stage cluster probability design., Results: Adolescents with asthma had a higher prevalence of current hookah (14.0%) and e-cigarette use (12.4%) compared with their peers (10.9%, 10.2%, respectively). Adolescents with asthma were also at increased risk for current use of cigarettes (adjusted odds ratio [AOR]: 1.24), hookah (AOR: 1.32), and e-cigarettes (AOR: 1.34). Adolescents with asthma reported positive beliefs about tobacco products and were more likely to report living with individuals who used cigarettes (31.5%), hookah (12.1%), and e-cigarettes (15.5%) compared with their peers (26.5%, 8.5%, 12.5%, respectively)., Conclusions: Adolescents with asthma reported tobacco product use, positive beliefs about tobacco products, and high potential home exposure to tobacco products. There is a pressing need for education regarding potential harm of alternative tobacco products among adolescents with asthma., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Molecular profiling of human diseases has been approached at the genetic (DNA), expression (RNA), and proteomic (protein) levels. An important goal of these efforts is to map observed molecular patterns to specific, mechanistic organic entities, such as loci in the genome, individual RNA molecules or defined proteins or protein assemblies. Importantly, such maps have been historically approached in the more intuitive context of a theoretical individual cell, but diseases are better described in reality using an in vivo framework, namely a library of several tissue-specific maps. In this article, we review the existing data atlases that can be used for this purpose and identify critical gaps that could move the field forward from cellular to in vivo dimensions. WIREs Syst Biol Med 2016, 8:472-484. doi: 10.1002/wsbm.1354 For further resources related to this article, please visit the WIREs website., (© 2016 Wiley Periodicals, Inc.)

In recent years, innovations in molecular techniques and sequencing technologies have resulted in a rapid expansion in the number of known viral sequences, in particular those with circular replication-associated protein (Rep)-encoding single-stranded (CRESS) DNA genomes. CRESS DNA viruses are present in the virome of many ecosystems and are known to infect a wide range of organisms. A large number of the recently identified CRESS DNA viruses cannot be classified into any known viral families, indicating that the current view of CRESS DNA viral sequence space is greatly underestimated. Animal faecal matter has proven to be a particularly useful source for sampling CRESS DNA viruses in an ecosystem, as it is cost-effective and non-invasive. In this study a viral metagenomic approach was used to explore the diversity of CRESS DNA viruses present in the faeces of domesticated and wild animals in New Zealand. Thirty-eight complete CRESS DNA viral genomes and two circular molecules (that may be defective molecules or single components of multicomponent genomes) were identified from forty-nine individual animal faecal samples. Based on shared genome organisations and sequence similarities, eighteen of the isolates were classified as gemycircularviruses and twelve isolates were classified as smacoviruses. The remaining eight isolates lack significant sequence similarity with any members of known CRESS DNA virus groups. This research adds significantly to our knowledge of CRESS DNA viral diversity in New Zealand, emphasising the prevalence of CRESS DNA viruses in nature, and reinforcing the suggestion that a large proportion of CRESS DNA viruses are yet to be identified., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: The Study to Explore Early Development (SEED) is designed to enhance knowledge of autism spectrum disorder characteristics and etiologies., Objective: This paper describes the demographic profile of enrolled families and examines sociodemographic differences between children with autism spectrum disorder and children with other developmental problems or who are typically developing., Methods: This multi-site case-control study used health, education, and birth certificate records to identify and enroll children aged 2-5 years into one of three groups: 1) cases (children with autism spectrum disorder), 2) developmental delay or disorder controls, or 3) general population controls. Study group classification was based on sampling source, prior diagnoses, and study screening tests and developmental evaluations. The child's primary caregiver provided demographic characteristics through a telephone (or occasionally face-to-face) interview. Groups were compared using ANOVA, chi-squared test, or multinomial logistic regression as appropriate., Results: Of 2768 study children, sizeable proportions were born to mothers of non-White race (31.7%), Hispanic ethnicity (11.4%), and foreign birth (17.6%); 33.0% of households had incomes below the US median. The autism spectrum disorder and population control groups differed significantly on nearly all sociodemographic parameters. In contrast, the autism spectrum disorder and developmental delay or disorder groups had generally similar sociodemographic characteristics., Conclusions: SEED enrolled a sociodemographically diverse sample, which will allow further, in-depth exploration of sociodemographic differences between study groups and provide novel opportunities to explore sociodemographic influences on etiologic risk factor associations with autism spectrum disorder and phenotypic subtypes., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Preclinical studies for neurodegenerative diseases have shown a multi-targeted approach to be successful in the treatment of these complex disorders with several pathoetiological pathways. Polycyclic compounds, such as NGP1-01 (7a), have demonstrated the ability to target multiple mechanisms of the complex etiology and are referred to as multifunctional compounds. These compounds have served as scaffolds with the ability to attenuate Ca(2+) overload and excitotoxicity through several pathways. In this study, our focus was on mitigating Ca(2+) overload through the L-type calcium channels (LTCC). Here, we report the synthesis and biological evaluation of several novel polycyclic compounds. We determined the IC50 values for both the pentacycloundecylamines and the triquinylamines by means of a high-throughput fluorescence calcium flux assay utilizing Fura-2/AM. The potential of these compounds to offer protection against hydrogen peroxide-induced cell death was also evaluated. Overall, 8-benzylamino-8,11-oxapentacyclo[5.4.0.0(2,6) .0(3,10) .0(5,9) ]undecane (NGP1-01, 7a) had the most favorable pharmacological profile with an IC50 value of 86 µM for LTCC inhibition and significant reduction of hydrogen peroxide-induced cell death. In general, the triquinylamines were more active as LTCC blockers than the oxa-pentacycloundecylamines. The aza-pentacycloundecylamines were potent LTCC inhibitors, with 8-hydroxy-N-phenylethyl-8,11-azapentacyclo[5.4.0.0(2,6) .0(3,10) .0(5,9) ]undecane (8b) also able to offer significant protection in the cell viability assays., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Electrospray ionisation-ion mobility spectrometry-mass spectrometry (ESI-IMS-MS) is a powerful method for the study of conformational changes in protein complexes, including oligomeric species populated during protein self-aggregation into amyloid fibrils. Information on the mass, stability, cross-sectional area and ligand binding capability of each transiently populated intermediate, present in the heterogeneous mixture of assembling species, can be determined individually in a single experiment in real-time. Determining the structural characterisation of oligomeric species and alterations in self-assembly pathways observed in the presence of small molecule inhibitors is of great importance, given the urgent demand for effective therapeutics. Recent studies have demonstrated the capability of ESI-IMS-MS to identify small molecule modulators of amyloid assembly and to determine the mechanism by which they interact (positive, negative, non-specific binding, or colloidal) in a high-throughput format. Here, we demonstrate these advances using self-assembly of Aβ40 as an example, and reveal two new inhibitors of Aβ40 fibrillation., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

Protein aggregation underlies an array of human diseases, yet only one small-molecule therapeutic targeting this process has been successfully developed to date. Here, we introduce an in vivo system, based on a β-lactamase tripartite fusion construct, that is capable of identifying aggregation-prone sequences in the periplasm of Escherichia coli and inhibitors that prevent their aberrant self-assembly. We demonstrate the power of the system using a range of proteins, from small unstructured peptides (islet amyloid polypeptide and amyloid β) to larger, folded immunoglobulin domains. Configured in a 48-well format, the split β-lactamase sensor readily differentiates between aggregation-prone and soluble sequences. Performing the assay in the presence of 109 compounds enabled a rank ordering of inhibition and revealed a new inhibitor of islet amyloid polypeptide aggregation. This platform can be applied to both amyloidogenic and other aggregation-prone systems, independent of sequence or size, and can identify small molecules or other factors able to ameliorate or inhibit protein aggregation.

Background: The speed of flea knockdown by different products and their duration of effectiveness are factors which affect veterinarian prescribing decisions. To further validate the month-long pulicidal effectiveness of spinosad and determine its rate of flea knockdown to that of afoxolaner, three studies were conducted in two laboratories in the United States, utilizing flea infestations from colonies which are regularly refreshed through introduction of locally caught fleas., Methods: All study assessors were blinded, dogs were ranked by pre-study flea counts and randomized accordingly, and treatments administered on Day 0. All studies included a negative control group; two also included an afoxolaner group. In one study, flea challenges for treated and control dogs (10 per group) were completed 21 and 28 days after treatment and counts were performed 24 h later. In each of two speed-of-knockdown (SOK) studies, 36 dogs were randomized, six dogs per group, to: untreated controls; administered oral afoxolaner (2.6-6.2 mg/kg); or oral spinosad (32.1-59.2 mg/kg). In the SOK studies, live fleas from Day -1 infestations were counted after being combed off at 1 and 3 h after treatment, and after reinfestations on Day 7., Results: There were no treatment-related adverse events. Spinosad was 98.6% effective at 28 days post treatment. For SOK, geometric mean live flea counts for afoxolaner were not different from controls at any assessment. For spinosad, all mean counts were significantly lower than in controls (p ≤ 0.0128) except at 1 h post treatment in both studies. Spinosad was significantly more effective than afoxolaner in both studies at 3 h post treatment (p ≤ 0.0065) and post-Day 7 infestation (p ≤ 0.0054), and at 1 h post treatment (p = 0.0276) and post-Day 7 infestation in one study., Conclusions: These data validate spinosad's faster onset of flea knockdown than afoxolaner against infestations present at the time of treatment, and faster residual speed of flea knockdown for at least 7 days post treatment, and confirm spinosad's extended residual speed of kill for at least 28 days post treatment.

The precise molecular mechanisms by which different peptides and proteins assemble into highly ordered amyloid deposits remain elusive. The fibrillation of human amylin (also known as islet amyloid polypeptide, hIAPP) and the amyloid-beta peptide (Aβ-40) are thought to be pathogenic factors in Type 2 diabetes mellitus (T2DM) and Alzheimer's disease (AD), respectively. Amyloid diseases may involve co-aggregation of different protein species, in addition to the self-assembly of single precursor sequences. Here we investigate the formation of heterogeneous pre-fibrillar, oligomeric species produced by the co-incubation of hIAPP and Aβ-40 using electrospray ionisation-ion mobility spectrometry-mass spectrometry (ESI-IMS-MS)-based methods. Conformational properties and gas-phase stabilities of amyloid oligomers formed from hIAPP or Aβ40 alone, and from a 1 : 1 mixture of hIAPP and Aβ40 monomers, were determined and compared. We show that co-assembly of the two sequences results in hetero-oligomers with distinct properties and aggregation kinetics properties compared with the homo-oligomers present in solution. The observations may be of key significance to unravelling the mechanisms of amyloid formation in vivo and elucidating how different sequences and/or assembly conditions can result in different fibril structures and/or pathogenic outcomes.

PARP1 is the main sensor of single- and double-strand breaks in DNA and, in building chains of poly(ADP-ribose), promotes the recruitment of many downstream signaling and effector proteins involved in the DNA damage response (DDR). We show a robust physical interaction between PARP1 and the replication fork protein TIMELESS, distinct from the known TIMELESS-TIPIN complex, which activates the intra-S phase checkpoint. TIMELESS recruitment to laser-induced sites of DNA damage is dependent on its binding to PARP1, but not PARP1 activity. We also find that the PARP1-TIMELESS complex contains a number of established PARP1 substrates, and TIMELESS mutants unable to bind PARP1 are impaired in their ability to bind PARP1 substrates. Further, PARP1 binding to certain substrates and their recruitment to DNA damage lesions is impaired by TIMELESS knockdown, and TIMELESS silencing significantly impairs DNA double-strand break repair. We hypothesize that TIMELESS cooperates in the PARP1-mediated DDR., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Brain recovery after cardiac arrest (CA) is sensitive to temperature. Yet the effect of temperature management on different EEG frequency bands has not been elucidated. A novel quantitative EEG algorithm, sub-band information quantity (SIQ), was applied to evaluate EEG recovery and outcomes after CA., Methods: Twenty-four Wistar rats undergoing 7-min CA were randomly assigned to immediate hypothermia (32-34 °C), normothermia (36.5-37.5 °C), or hyperthermia (38.5-39.5 °C) (n = 8). EEG was recorded continuously for the first 8 h and then for serial 30-min epochs daily. The neurologic deficit score (NDS) at 72-h was the primary functional outcome. Another four rats without brain injury were added as a control., Results: Better recovery of gamma-band SIQ was found in the hypothermia group (0.60 ± 0.03) compared with the normothermia group (0.40 ± 0.03) (p < 0.01) and in the normothermia group compared with the hyperthermia group (0.34 ± 0.03) (p < 0.05). The NDS was also improved in the lower temperature groups: hypothermia [median (25th, 75th), 74 (61, 74)] versus normothermia [49 (47, 61)] versus hyperthermia [43 (0, 50)] (p < 0.01). Throughout the 72-h experiment, the gamma-band SIQ showed the strongest correlation at every time point (ranging 0.520-0.788 from 30-min to 72-h post-resuscitation, all p < 0.05) whereas the delta-band SIQ had poor correlation with the 72-h NDS. No significant difference of sub-band EEG was found with temperature manipulation alone., Conclusions: Recovery of gamma-band SIQ-qEEG was strongly associated with functional outcomes after CA. Induced hypothermia was associated with faster recovery of gamma-band SIQ and improved functional outcomes. Targeted temperature management primarily affected gamma frequency oscillations but not delta rhythm.

Bed rest-induced muscle loss and impaired muscle recovery may contribute to age-related sarcopenia. It is unknown if there are age-related differences in muscle mass and muscle anabolic and catabolic responses to bed rest. A secondary objective was to determine if rehabilitation could reverse bed rest responses. Nine older and fourteen young adults participated in a 5-day bed rest challenge (BED REST). This was followed by 8 weeks of high intensity resistance exercise (REHAB). Leg lean mass (via dual-energy X-ray absorptiometry; DXA) and strength were determined. Muscle biopsies were collected during a constant stable isotope infusion in the postabsorptive state and after essential amino acid (EAA) ingestion on three occasions: before (PRE), after bed rest and after rehabilitation. Samples were assessed for protein synthesis, mTORC1 signalling, REDD1/2 expression and molecular markers related to muscle proteolysis (MURF1, MAFBX, AMPKα, LC3II/I, Beclin1). We found that leg lean mass and strength decreased in older but not younger adults after bedrest (P < 0.05) and was restored after rehabilitation. EAA-induced mTORC1 signalling and protein synthesis increased before bed rest in both age groups (P < 0.05). Although both groups had blunted mTORC1 signalling, increased REDD2 and MURF1 mRNA after bedrest, only older adults had reduced EAA-induced protein synthesis rates and increased MAFBX mRNA, p-AMPKα and the LC3II/I ratio (P < 0.05). We conclude that older adults are more susceptible than young persons to muscle loss after short-term bed rest. This may be partially explained by a combined suppression of protein synthesis and a marginal increase in proteolytic markers. Finally, rehabilitation restored bed rest-induced deficits in lean mass and strength in older adults., (© 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.)

Ethnopharmacological Relevance: Many different tribes of American Indians used jewelweed, Impatiens capensis Meerb, as a plant mash to reduce development of poison ivy dermatitis. Saponins are a natural soapy constituent found within plants. A 2012 study suggested that saponins may be present in jewelweed which could be responsible for its efficacy in preventing rash development following contact with Toxicodendron radicans (L.) Kuntze (poison ivy). This study validated this hypothesis and demonstrated additional biological activity of the jewelweed saponin containing extract., Materials and Methods: Fresh I. capensis leaves were extracted with methanol and further partitioned between ethyl acetate and water, with a final separation between water and n-butanol, to obtain a saponin containing extract. The presence of saponins in the extract was demonstrated by the observation of foaming and using a vanillin colorimetric assay for total saponins. Efficacy of the saponin containing extracts in rash reduction was tested by brushing poison ivy (PI) onto the forearms of volunteers (N=23) in six locations and treating these PI exposed areas with distilled water (control), saponin containing extracts, fresh plant mashes, and soaps made with and without plant extracts. Saponin containing extracts were further tested for biological activity against both gram negative and gram positive bacteria and against cancer cell lines A-375, HT-29, and MCF-7. Additionally, because saponins have been shown to have a stimulatory effect in cardiac muscle 2 µl saponin extract was applied superficially to black worms, Lumbriculus variegatus (N=5)., Results, and Conclusions: Both saponin containing extracts and all soaps tested were effective in reducing poison ivy dermatitis; thus, saponin content correlates with PI rash prevention. No apparent antibiosis was observed against any bacteria tested; however, dose response cytotoxicity was documented against MCF-7 breast cancer cells and cytostatic activity was seen against the HT-29 colon cancer cell lines. Lumbriculus variegatus exhibited a 138% increase in heart rate over baseline rate five minutes post treatment implying a possible positive chronotropic effect., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

The process of amyloid formation by the normally soluble hormone islet amyloid polypeptide (IAPP) contributes to β-cell death in type 2 diabetes and in islet transplants. There are no clinically approved inhibitors of islet amyloidosis, and the mode of action of existing inhibitors is not well-understood. Resveratrol, a natural polyphenol, has been reported to inhibit amyloid formation by IAPP and by the Alzheimer's disease Aβ peptide. The mechanism of action of this compound is not known, nor is its mode of interaction with IAPP. In this study, we use a series of IAPP variants to examine possible interactions between resveratrol and IAPP. Fluorescence assays, transmission electron microscopy, and mass spectrometry demonstrate that resveratrol is much less effective as an inhibitor of IAPP amyloid formation than the polyphenol (-)-epigallocatechin 3-gallate (EGCG) and, unlike EGCG, does not significantly disaggregate preformed IAPP amyloid fibrils. Resveratrol is also shown to interfere with thioflavin-T assays. His-18 mutants, a truncation mutant, mutants of each of the aromatic residues, and mutants of Arg-11 of IAPP were examined. Mutation of His to Gln or Leu weakens the ability of resveratrol to inhibit amyloid formation by IAPP, as do mutations of Arg-11, Phe-15, or Tyr-37 to Leu, and truncation to form the variant Ac 8-37-IAPP, which removes the first seven residues to eliminate Lys-1 and the N-terminal amino group. In contrast, replacement of Phe-23 with Leu has a smaller effect. The data highlight Phe-15, His-18, and Tyr-37 as being important for IAPP-resveratrol interactions and are consistent with a potential role of the N-terminus and Arg-11 in polypeptide-resveratrol interactions.

The search for therapeutic agents that bind specifically to precursor protein conformations and inhibit amyloid assembly is an important challenge. Identifying such inhibitors is difficult because many protein precursors of aggregation are partially folded or intrinsically disordered, which rules out structure-based design. Furthermore, inhibitors can act by a variety of mechanisms, including specific or nonspecific binding, as well as colloidal inhibition. Here we report a high-throughput method based on ion mobility spectrometry-mass spectrometry (IMS-MS) that is capable of rapidly detecting small molecules that bind to amyloid precursors, identifying the interacting protein species and defining the mode of inhibition. Using this method we have classified a variety of small molecules that are potential inhibitors of human islet amyloid polypeptide (hIAPP) aggregation or amyloid-beta 1-40 aggregation as specific, nonspecific, colloidal or non-interacting. We also demonstrate the ability of IMS-MS to screen for inhibitory small molecules in a 96-well plate format and use this to discover a new inhibitor of hIAPP amyloid assembly.

Therapeutic hypothermia has been regarded as one of the most effective post-cardiac arrest (CA) treatments to improve survival and functional recovery. However, many clinical prognostic markers after resuscitation have become less reliable under hypothermia. In this study, we applied and compared two developed quantitative measures - information quantity (IQ) and sub-band IQ (SIQ) - to evaluate the accuracy of EEG markers on predicting cortical recovery under therapeutic hypothermia. A total of 14 rats under 9-min asphyxial-CA, leading to severe brain injury, were randomly divided into two groups: hypothermia (32°C-34°C) and normothermia (36.5-37.5°C) (n=7 per group). For each rat, EEG and temperature were continuously recorded for the first 15 hrs. EEG was then recorded for serial 30 mins at 24, 48 and 72 hrs. The neurologic deficit score was evaluated daily to assess the neurologic recovery. Early SIQ and IQ were both significantly correlated with the 72-hr NDS, when the rats remained comatose. Both IQ and SIQ were able to discriminate the animals with good and bad functional outcomes starting from 1 hr after resuscitation. There was no significant difference in 72-hr NDS results (hypothermia (median (25th, 75th), 65 (52, 67)) versus normothermia (53.5 (52.25, 66.75))) (p>0.05) due to the high mortality rate (5/14) with severe brain injury. Contrary to IQ recovery but similarly to NDS scores, the SIQ recovery was not significantly different between the hypothermia (0.66±0.04) and normothermia (0.64±0.04) groups (p>0.05). IQ could identify the presence of high-frequency oscillations during the recovery from severe brain injury. We demonstrated that while SIQ was able to provide additional sub-band EEG information related to the recovery of different brain functions, both early IQ and SIQ markers are able to accurately predict neurologic outcome after CA.

When the University of Mississippi Medical Center embraced a didactic shift to patient-centered, interprofessional education of its medical, dental, nursing, pharmacy, and allied health students, the Rowland Medical Library repurposed space to support the cause and created a collaborative learning space designated for campus-wide utility.

Physical abuse of the elderly is a significant public health concern. The true prevalence of all types is unknown, and under-reporting is known to be significant. The geriatric population is projected to increase dramatically over the next 10 years, and the number of abused individuals is projected to increase also. It is critical that health care providers feel competent in addressing physical elder abuse. This article presents cases illustrating the variety of presenting symptoms that may be attributed to physical elder abuse., (Copyright © 2014 Elsevier Inc. All rights reserved.)

The task of rapid detection and identification of bacteria remains a major challenge in both medicine and industry. This work introduces a new concept for the design of self-reporting optical structures that can detect and quantify bacteria in real-time. The sensor is based on a two-dimensional periodic structure of porous Si photonic crystals in which the pore size is adjusted to fit the target bacteria cells (Escherichia coli). Spontaneous bacteria capture within the pores induces measurable changes in the zero-order reflectivity spectrum collected from the periodic structure. Confocal laser microscopy and electron microscopy confirm that the Escherichia coli cells are individually imprisoned within the porous array. A simple model is suggested to correlate the optical readout and the bacteria concentration and its predictions are found to be in good agreement with experimental results. In addition, we demonstrate that sensing scheme can be easily modified to potentially allow monitoring of concentration, growth and physiological state of bacteria cells. This generic platform can be tailored to target different microorganisms by tuning the array periodicity and its surface chemistry for rapid and label-free detection outside the laboratory environment.

The molecular mechanisms by which different proteins assemble into highly ordered fibrillar deposits and cause disease remain topics of debate. Human amylin (also known as islet amyloid polypeptide/hIAPP) is found in vivo as amyloid deposits in the pancreatic islets of sufferers of type II diabetes mellitus, and its self-aggregation is thought to be a pathogenic factor in disease and to contribute to the failure of islet transplants. Here, electrospray ionization-ion mobility spectrometry-mass spectrometry (ESI-IMS-MS) has been used to monitor oligomer formation from IAPP. The detection, identification and characterization of oligomers from both human and rat amylin (rIAPP) are described. Oligomers up to and including hexamers have been detected for both peptides. From ESI-IMS-MS derived collision cross sections (CCS), these species are shown to be elongated in conformation. Collision-induced dissociation (CID-MS/MS) revealed differences in the gas-phase stability of the oligomers formed from hIAPP and rIAPP, which may contribute to their differences in amyloid propensity. Using ESI-IMS-MS, the mode of inhibition of amyloid formation from hIAPP using small molecules or co-incubation with rIAPP was also investigated. We show that the polyphenolic compounds epigallocatechin gallate (EGCG) and silibinin bind to specific conformers within a dynamic ensemble of hIAPP monomers, altering the progress of oligomerization and fibril assembly. Hetero-oligomer formation also occurs with rIAPP but leads only to inefficient inhibition. The results indicate that although different small molecules can be effective inhibitors of hIAPP self-assembly, their modes of action are distinct and can be distinguished using ESI-IMS-MS.

Background: A formulation containing 39.6% spinetoram resulted in a higher than anticipated number of reports of alopecia at the site of application in the first months following commercial product launch., Hypothesis/objectives: To determine the cause of the alopecia using histopathology, including assessment for inflammation, follicular findings of physical trauma (plucking/pulling behaviour) and changes in follicular cycling., Animals: Twenty-four flea-free, male and female adult domestic short hair cats within a private research colony., Methods: Cats were treated with a single application of 39.6% spinetoram on day 0; personnel were not blinded. Observations of the skin and hair coat began immediately and were repeated at 30 min and 1, 2, 3, 4, 6, 8 and 12 h post-application and then on subsequent days at the same time as initial dosing and at 2, 4, 6, 8 and 12 h after that time, until day 5. If hair thinning or loss was observed, a skin biopsy sample was collected. Two cats not exhibiting abnormalities were biopsied on day 6., Results: Thirty-eight per cent of cats (nine of 24) developed hair thinning and alopecia of sufficient severity within 78 h post-application of the product to warrant skin biopsy. Abnormalities in the skin were limited to the application site and were consistent with physical trauma (pulling or plucking) to the hair., Conclusions and Clinical Importance: Microscopic changes in the hair follicles of affected cats were consistent with self-induced trauma or barbering behaviour. All changes were reversible and paralleled findings associated with well-established, topical flea control products., (© 2013 ESVD and ACVD.)

A wide variety of novel single-stranded DNA (ssDNA) viruses have been found in faecal matter of chimpanzees, cows, rodents, bats, badgers, foxes and pigs over the last few years. Using a combination of rolling circle amplification coupled with restriction enzyme digests based approach as well as a next generation sequencing informed approach, we have recovered fourteen full genomes of ssDNA viruses which exhibit genomic features described for members of the recently proposed gemycircularvirus group from a wide variety of mammal and bird faecal samples across New Zealand. The fourteen novel ssDNA viruses (2122-2290nt) encode two major proteins, a replication associated protein (Rep) and a capsid protein (Cp) which are bi-directionally transcribed. Interestingly, the Rep of these novel viruses are similar to gemycircularviruses detected in insects, cassava leaves, and badger faecal matter, the novel viruses share sequence similarities with the mycovirus sclerotinia sclerotiorum hypovirulence-associated DNA virus 1 (SsHADV-1) and Rep-like sequences found in fungal genomes. Pairwise sequence similarities between the 14 novel genomes with other related viral isolates (gemycircularviruses) indicated that they share greater than 55.8% genome-wide identity. Additionally, they share between 55% and 59% pairwise identity with putative novel ssDNA virus genomes recently isolated from sewage baminivirus, niminivirus and nephavirus. Based on the similarities to SsHADV-1 and Rep-like sequences found in fungal genomes, these novel gemycircularviruses may infect fungi., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A novel, empirical, macroscopic model is developed to describe the release of a model anticancer drug, Mitoxantrone, from native and chemically modified porous Si (PSi) thin films. Drug release from these carriers results from a combination of two mechanisms, i.e. out-diffusion of the drug molecules and erosion of the Si scaffold. Thus, the proposed mathematical model adapts the Crank model to lump the effects of temporal changes in molecular interactions and carrier scaffold erosion into a comprehensive model of hindered drug diffusion from nanoscale porous systems. Careful characterization of pore size, porosity, surface area, drug loading, as well as Si scaffold degradation profiles, measured over the same time-scale as drug release, are incorporated into the model parameter estimation. A comparison of the experimental and model results shows accurate representation of the data, emphasizing the reliability of the model. The proposed model shows that drug diffusivity values significantly vary with time for the two studied carriers, which are ascribed to the distinctive role of the prevailing physical mechanisms in each system. Finally, secondary validation of the proposed model is demonstrated by showing adequate fit to published data of the release of dexamethasone from similar mesoporous Si carriers., (Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

This study examined inflammatory cell and cytokine production in brain tissue from a lipopolysaccharide (LPS)-treated rat model that mimics many of the neuropathologic changes associated with neurodegenerative diseases We also monitored the appearance of a glial cell line-derived neurotrophic factor (GDNF) and circulating nitric oxide (NO) levels, as well as an immune system-associated cells in a selected area of the brain, the olfactory lobe. The studies were based on the hypothesis that LPS treatment stimulates temporal changes within the brain and that these responses include immune cell recruitment, increased tissue levels of immune modulating cytokines and NO, as well as greater glial cell activation resulting in increased production of GDNF. As previously reported by other investigators, our animal model of systemic LPS treatment leads to an increase in the concentrations of circulating cytokines, including TNF-α, IL-Iβ, and IL-6, with a maximum response 6 h post LPS administration. Concomitant with cytokine elevations, circulating NO levels were elevated for several hours post LPS administration. The brain content of the GDNF was also elevated over a similar time frame. Lymphocytes, neutrophils, macrophages, plasma cells, and cytokines were all seen in various areas of LPS-treated brains, often around blood vessels associated with the meninges, with these localizations possibly indicating involvement of both the blood-brain and blood-cerebral spinal fluid barriers in these inflammatory episodes. Our results suggest an involvement of both the peripheral and the central nervous system immune components in response to inflammation and inflammatory episodes. This leads us to propose that inflammation initiates an immune response by activating both microglia and astrocytes and that the presence of continuing and increasing proinflammatory mechanisms results in a situation, where cellular protective mechanisms are overcome and the more susceptible cells enter into cell death pathways, initiating a train of events that is a major part of neurodegeneration.

Monitoring of the performance of flea control products under conditions of natural challenge is valuable in assessing continued effectiveness and determining the ongoing relevance of laboratory studies. A multi-clinic, investigator-blinded study was undertaken in client-owned dogs to investigate and compare the flea control provided by 3 consecutive monthly treatments of oral spinosad (SPN) or fipronil/(S)-methoprene topical (FSM) spot-on. The first household dog meeting enrollment criteria and with at least 10 fleas (whole-body flea count) served as the index dog in a household against which primary objectives were set. Stratification was based on pruritus scores at the enrollment visit and on single or multiple pet household. Index pets were randomized to treatment with either SPN or FSM, dispensed on day 0 for at-home administration by owners. All other household dogs and cats, maximum 4 pets per household, were dispensed the same treatment as the index dog (spinetoram was dispensed for cats in SPN households). Subsequent treatments were dispensed when index dogs were returned for whole-body flea counts and pruritus-scoring at visits on days 30 and 60, with final assessments on day 90 (±5 days on each occasion). Primary endpoints were the number of flea-free index dogs in each group one month after the final treatment, the reduction in owner-reported pruritus, and the reduction from baseline mean flea counts. One hundred twenty eight index dogs were enrolled (65 in the SPN arm; 63 in the FSM arm) at 10 clinics in FL (6), NC (2), LA (1), and TX (1). On day 0, geometric mean flea counts were 57.7 (range: 10-1469) and 44.8 (10-717) for the SPN and FSM groups, respectively. On Day 90, 55 of 58 (95%) and 21 of 55 (38%) index dogs completing the study were flea-free in SPN and FSM groups, respectively; mean SPN pruritus scores declined to 0.92 (6.67 on day 0), and to 3.83 (6.33 on day 0) for FSM; geometric mean flea counts (% control) were 0.08 (99.9%) and 5.19 (88.4%), for SPN and FSM groups, respectively. Between-treatment differences were highly statistically significant (p<0.0001). In conclusion, SPN provided reliable flea control in client-owned dogs, regardless of challenge level., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Background and Objective: Obstructive airflow limitation is the most common physiological impairment in sarcoidosis. This study determined the prevalence of airway hyperresponsiveness (AHR) in sarcoidosis, the correlation between responses to direct (using histamine) and indirect (using hypertonic saline) bronchial challenge, and the clinical, physiological and radiological predictors of AHR., Methods: Subjects with sarcoidosis and a baseline forced expiratory volume in 1 s (FEV(1)) >35% predicted underwent hypertonic and histamine challenge, lung function testing and high resolution computed tomography (HRCT) of the chest. AHR was defined as a 15% fall in FEV(1) to hypertonic saline and a 20% fall in FEV(1) to histamine., Results: The 52 subjects had well-preserved lung function (FEV(1) = 2.8 ± 0.7 L, 87% predicted). AHR was detected in 5/47 (11%) to hypertonic saline and 19/43 (44%) to histamine challenge. On univariate analysis, response to histamine challenge was predicted by conglomerate fibrosis (P = 0.02) and reticular pattern (P = 0.03) on HRCT. The baseline % predicted forced expiratory volume in 1 s was significantly inversely associated with AHR on univariate (P = 0.004) and multivariate analysis (P = 0.01) when adjusted by HRCT patterns., Conclusions: The higher prevalence of AHR using histamine challenge than hypertonic saline challenge and the association with baseline % predicted FEV(1) suggest that the AHR in sarcoidosis may reflect the consequences of airway remodelling following inflammation., (© 2012 The Authors. Respirology © 2012 Asian Pacific Society of Respirology.)

Much of our knowledge of galaxies comes from analysing the radiation emitted by their stars, which depends on the present number of each type of star in the galaxy. The present number depends on the stellar initial mass function (IMF), which describes the distribution of stellar masses when the population formed, and knowledge of it is critical to almost every aspect of galaxy evolution. More than 50 years after the first IMF determination, no consensus has emerged on whether it is universal among different types of galaxies. Previous studies indicated that the IMF and the dark matter fraction in galaxy centres cannot both be universal, but they could not convincingly discriminate between the two possibilities. Only recently were indications found that massive elliptical galaxies may not have the same IMF as the Milky Way. Here we report a study of the two-dimensional stellar kinematics for the large representative ATLAS(3D) sample of nearby early-type galaxies spanning two orders of magnitude in stellar mass, using detailed dynamical models. We find a strong systematic variation in IMF in early-type galaxies as a function of their stellar mass-to-light ratios, producing differences of a factor of up to three in galactic stellar mass. This implies that a galaxy's IMF depends intimately on the galaxy's formation history.

This study evaluated the use of two different case study formats (clinically-oriented cases versus personally-oriented cases) to determine which was most effective in promoting long-term retention of clinically significant microbiology concepts, developing patient empathy, improving comprehension of patient compliance problems, and facilitating student understanding of transcultural health care concerns. The analysis was conducted in multiple sections of three different introductory microbiology classes targeting specific cohorts: nursing students, pharmacy students and other allied health students (pre-med, pre-PA, CLS, etc.). Retention of course content was determined by evaluation of multiple-choice and short answer examinations at least three weeks after completing case studies. Evaluation of patient empathy, understanding of patient compliance issues and transcultural health care concerns were determined via student surveys. The results of the study indicated that personalized cases significantly improved long-term retention of course content. In addition, student responses indicated that personalized case studies were more effective in developing patient empathy and aiding students in understanding issues patients have with complying with treatment recommendations. Finally, personalized case studies were effective tools for introducing students to the challenges of transcultural health care.

Objective: The neovascularization of malignant brain tumors is a poorly understood phenomenon. Radiographic and histological evidence of increased vascularity correlate with clinical grade of gliomas. However, a quantitative noninvasive assay to assess glioma vascularity and associated clinical aggressiveness has not been developed. Circulating endothelial progenitor cells are unique vascular precursors recruited from the bone marrow through the circulation to form new tumor blood vessels. These cells were measured in patients undergoing surgery for glioblastoma multiforme (GBM). We hypothesized that this might reflect the extent of tumor vascularity, predict prognosis, or be useful as an assay to assess response to antiangiogenesis therapies. In addition, we report on a novel in vitro assay to assess the proangiogenic activity within the plasma samples obtained from glioma patients., Methods: Fifty-six patients with various-grade gliomas had peripheral venous blood collected at the time of surgery and at subsequent visits during the follow-up period. The blood was separated into plasma and cellular fractions. The plasma was utilized in a human umbilical vein endothelial cell-based angiogenic assay. The cellular fraction containing endothelial progenitor cells was isolated, and specific cellular phenotypes were immunologically separated and counted using flow cytometry. Pathological samples were reviewed at the time of initial resection, and each patient's clinical course was monitored until the time of manuscript submission., Results: Plasma derived from peripheral blood of patients with GBM scored significantly higher on the functional angiogenic scale compared with plasma derived from patients with low-grade gliomas and from controls. In addition, all patients with GBM had measurable numbers of bone marrow-derived endothelial precursor cells coexpressing CD133 and vascular endothelial growth factor receptor 2 in their peripheral circulation at the time of tumor resection. These cells range from less than 0.1% to 1.6% of the entire circulating mononuclear white blood cell population, or approximately 200,000 cells in some patients. A statistically significant relationship was observed between the percentage of endothelial progenitor cells in the peripheral blood at the time of initial GBM resection and survival., Conclusion: These studies suggest that plasma and circulating CD133+ vascular endothelial growth factor receptor 2+ proangiogenic cells are present in the peripheral blood of patients with glioma and can be used as a surrogate biomarker to measure tumor angiogenicity. These cells can be measured at the time of diagnosis and monitored in the postoperative period. These assays can be used to predict tumor aggressiveness. Also promising is their potential to identify patients with increased angiogenic activity who might respond maximally to antiangiogenesis therapies or to assess tumor response in patients using those therapies as the use of these adjuvant molecular modalities becomes more prevalent in neuro-oncology.

Citizen participation is heralded as a critical element of community health programs that emphasize empowerment and health promotion strategies. Although there is a growing body of research on public health nurses' primary health care practice, few studies have described how public health nurses foster citizen participation. This article presents findings from an interpretive qualitative study of public health nurses' perceptions of their role in fostering citizen participation in an eastern Canadian province at a time of significant health care restructuring. The findings from this study clearly profile public health nurses as integral to the practice of fostering citizen participation.

Objective: This study examines developmental change and intraindividual stability in girls' fat stereotypes and associations between girls' internalization of stereotypes and their psychosocial well-being., Methods and Procedures: Participants included 163 non-Hispanic white girls. Girls' fat stereotypes were assessed at ages 9 and 11 years and their height and weight and all measures of psychosocial well-being, including global self-worth, perceived physical appearance, and maladaptive eating attitudes, were assessed at ages 9, 11, and 13 years. Change in girls' fat stereotypes between ages 9 and 11 was assessed using Repeated Measures ANOVA. Intraindividual stability in stereotypes was assessed using Spearman rank correlation analysis. Planned comparisons were used to test the hypothesis that overweight girls who internalize fat stereotypes are at heightened risk of poor psychosocial well-being., Results: Girls' fat stereotypes decreased significantly between ages 9 and 11. Moderate intraindividual stability was observed in overweight girls', but not nonoverweight girls', reported stereotypes. As predicted, overweight girls who reported high fat stereotypes reported significantly lower psychosocial well-being than all other girls in the sample, independent of their weight status., Discussion: Findings suggest that overweight girls may be particularly sensitive to weight-based stereotypes and may experience poor psychosocial well-being when they internalize stereotypes. Health practitioners working with overweight girls need to be aware of girls' sensitivity to weight-based stereotypes and should actively work against condoning and reinforcing such stereotypes.

Background: Necrotizing fasciitis (NF) is an uncommon fulminant soft tissue infection characterized by extensive fascial necrosis. Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) isolates producing the Panton-Valentine leukocidin (PVL) cytotoxin have been associated with serious necrotizing infections, but NF caused by CA-MRSA has been described only recently. We reviewed our NF experience at Denver Health Medical Center, where CA-MRSA accounts for more than 50% of community S. aureus clinical isolates., Methods: Patients treated for NF from January 2004 to February 2006 were identified by review of pathology records and diagnostic codes, and their medical records were reviewed. Isolates of MRSA from monomicrobial NF underwent testing for the PVL gene and pulsed-field gel electrophoresis to determine relatedness to CA-MRSA strains., Results: Five of 30 NF cases during the study period, all involving the extremities, were caused by MRSA. Monomicrobial MRSA NF accounted for three cases, with all of the patients reporting a distinct "spider bite" lesion 2-3 days prior to admission. The median age was 32 years (range 28-55 years). Resistance to erythromycin and levofloxacin was present in four isolates. None of the isolates displayed inducible clindamycin resistance. Within 12 hours of admission, all patients received empiric antibiotics to which their isolate was susceptible. Patients required a median of six surgical procedures (range 2-7 operations). All patients survived. The MRSA isolates tested positive for PVL and had the USA 300 CA-MRSA deoxyribonucleic acid banding pattern., Conclusions: Community-acquired MRSA is an important cause of NF in our region, accounting for > 15% of NF cases. This infection was associated with significant morbidity necessitating multiple surgical interventions. Given the propensity of PVL-positive CA-MRSA to cause severe necrotizing infections, it is reasonable to administer empiric MRSA coverage for NF in endemic locations.

The amyloid precursor protein (APP) plays a central role in Alzheimer's disease, but its actions in normal development are not well understood. Here, a tagged APP ectodomain was used to identify extracellular binding partners in developing chick brain. Prominent binding sites were seen in the olfactory bulb and on retinal axons growing into the optic tectum. Co-precipitation from these tissues and tandem mass spectrometry led to the identification of two associated proteins: contactin 4 and NgCAM. In vitro binding studies revealed direct interactions among multiple members of the APP and contactin protein families. Levels of the APP processing fragment, CTFalpha, were modulated by both contactin 4 and NgCAM. In the developing retinotectal system, APP, contactin 4 and NgCAM are expressed in the retina and tectum in suitable locations to interact. Functional assays revealed regulatory effects of both APP and contactin 4 on NgCAM-dependent growth of cultured retinal axons, demonstrating specific functional interactions among these proteins. These studies identify novel binding and functional interactions among proteins of the APP, contactin and L1CAM families, with general implications for mechanisms of APP action in neural development and disease.

Objective: Idiopathic pulmonary fibrosis (IPF), a chronic fibro-proliferative interstitial pneumonia, has not been reported to occur more frequently in any particular race. We have observed that our patients with IPF comprise a proportionately lower number of Maori and Pacific Islanders and set out to evaluate this further., Methods: Retrospective analysis of an IPF database from a single tertiary respiratory institution was undertaken. Demographic and survival data were collected. Ethnicity was compared with 2001 New Zealand census data from the same catchment area., Results: Eighty-seven cases of IPF were identified. Overall median survival was 46 months. Ethnicity data were available for 84 of the 87 cases. 76/84 (90%) were European, 6/84 (7%) were Asian or Indian, 2/84 (2%) were Maori, and 0/84 (0%) were Pacific Islanders. For Maori and Pacific Islanders, this represented a significant trend in difference when compared with ethnicity data from the hospital catchment population (P < 0.001)., Conclusions: Our department is the tertiary referral centre for pulmonary disease in the upper North Island of New Zealand, and therefore referral centre bias is likely to be low. The preliminary observation that the occurrence of IPF is lower in those of Maori or Polynesian ethnicity warrants further study. This may, in part, help in our understanding of the pathogenic mechanisms in IPF.

The Child Health Network for the Greater Toronto Area (CHN), a network of 20 hospitals and 9 community care access centres, assessed one component of its early progress in building a regionalized system of perinatal care. Focusing on the relationship between hospital level of care and gestational age, the study showed that most births occurred at appropriately designated facilities. However, a quarter of newborns of gestational age <32 weeks were delivered at a lower level of care than is considered optimal. CHN's ongoing research will offer opportunities to assess the impact of regional models on their foremost goal--quality clinical care.

The mechanisms through which hematopoietic cytokines accelerate revascularization are unknown. Here, we show that the magnitude of cytokine-mediated release of SDF-1 from platelets and the recruitment of nonendothelial CXCR4+ VEGFR1+ hematopoietic progenitors, 'hemangiocytes,' constitute the major determinant of revascularization. Soluble Kit-ligand (sKitL), thrombopoietin (TPO, encoded by Thpo) and, to a lesser extent, erythropoietin (EPO) and granulocyte-macrophage colony-stimulating factor (GM-CSF) induced the release of SDF-1 from platelets, enhancing neovascularization through mobilization of CXCR4+ VEGFR1+ hemangiocytes. Although revascularization of ischemic hindlimbs was partially diminished in mice deficient in both GM-CSF and G-CSF (Csf2-/- Csf3-/-), profound impairment in neovascularization was detected in sKitL-deficient Mmp9-/- as well as thrombocytopenic Thpo-/- and TPO receptor-deficient (Mpl-/-) mice. SDF-1-mediated mobilization and incorporation of hemangiocytes into ischemic limbs were impaired in Thpo-/-, Mpl-/- and Mmp9-/- mice. Transplantation of CXCR4+ VEGFR1+ hemangiocytes into Mmp9-/- mice restored revascularization, whereas inhibition of CXCR4 abrogated cytokine- and VEGF-A-mediated mobilization of CXCR4+ VEGFR1+ cells and suppressed angiogenesis. In conclusion, hematopoietic cytokines, through graded deployment of SDF-1 from platelets, support mobilization and recruitment of CXCR4+ VEGFR1+ hemangiocytes, whereas VEGFR1 is essential for their angiogenic competency for augmenting revascularization. Delivery of SDF-1 may be effective in restoring angiogenesis in individuals with vasculopathies.

The ability to map plastic deformation around high strain gradient microstructural features is central in studying phenomena such as fatigue and stress corrosion cracking. A method for the visualization of plastic deformation in electron back-scattered diffraction (EBSD) data has been developed and is described in this article. This technique is based on mapping the intragrain misorientation in polycrystalline metals. The algorithm maps the scalar misorientation between a local minimum misorientation reference pixel and every other pixel within an individual grain. A map around the corner of a Vickers indentation in 304 stainless steel was used as a test case. Several algorithms for EBSD mapping were then applied to the deformation distributions around air fatigue and stress corrosion cracks in 304 stainless steel. Using this technique, clear visualization of a deformation zone around high strain gradient microstructural features (crack tips, indentations, etc.) is possible with standard EBSD data.

The molecular and cellular pathways that support the maintenance and stability of tumor neovessels are not well defined. The efficacy of microtubule-disrupting agents, such as combretastatin A4 phosphate (CA4P), in inducing rapid regression of specific subsets of tumor neovessels has opened up new avenues of research to identify factors that support tumor neoangiogenesis. Herein, we show that CA4P selectively targeted endothelial cells, but not smooth muscle cells, and induced regression of unstable nascent tumor neovessels by rapidly disrupting the molecular engagement of the endothelial cell-specific junctional molecule vascular endothelial-cadherin (VE-cadherin) in vitro and in vivo in mice. CA4P increases endothelial cell permeability, while inhibiting endothelial cell migration and capillary tube formation predominantly through disruption of VE-cadherin/beta-catenin/Akt signaling pathway, thereby leading to rapid vascular collapse and tumor necrosis. Remarkably, stabilization of VE-cadherin signaling in endothelial cells with adenovirus E4 gene or ensheathment with smooth muscle cells confers resistance to CA4P. CA4P synergizes with low and nontoxic doses of neutralizing mAbs to VE-cadherin by blocking assembly of neovessels, thereby inhibiting tumor growth. These data suggest that the microtubule-targeting agent CA4P selectively induces regression of unstable tumor neovessels, in part through disruption of VE-cadherin signaling. Combined treatment with anti-VE-cadherin agents in conjunction with microtubule-disrupting agents provides a novel synergistic strategy to selectively disrupt assembly and induce regression of nascent tumor neovessels, with minimal toxicity and without affecting normal stabilized vasculature.

Connexins (Cxs) provide a means for intercellular communication and play important roles in the pathophysiology of vascular cardiac diseases. Infection of endothelial cells (ECs) with first-generation E1/E3-deleted E4+ adenovirus (AdE4+) selectively modulates the survival and angiogenic potential of ECs by as of yet unrecognized mechanisms. We show here that AdE4+ vectors potentiate Cx expression in ECs in vitro and in mouse heart tissue. Infection of ECs with AdE4+, but not AdE4-, resulted in a time- and dose-dependent induction of junctional Cx40 expression and suppression of Cx43 protein and mRNA expression. Treatment of ECs with PKA inhibitor H89 or PI3K inhibitor LY294002 prevented the AdE4+-mediated regulation of Cx40 and Cx43 that was associated with diminished AdE4+-mediated survival of ECs. Moreover, both PKA activity and cAMP-response element (CRE)-binding activity were enhanced by treatment of ECs with AdE4+. However, there is no causal evidence of a cross-talk between the 2 modulatory pathways, PKA and PI3K. Remarkably, Cx40 immunostaining was markedly increased and Cx43 was decreased in the heart tissue of mice treated with intra-tracheal AdE4+. Taken together, these results suggest that AdE4+ may play an important role in the regulation of Cx expression in ECs, and that these effects are mediated by both the PKA/CREB and PI3K signaling pathways.

Mutations that inactivate the retinoblastoma (Rb) pathway are common in human tumors. Such mutations promote tumor growth by deregulating the G1 cell cycle checkpoint. However, uncontrolled cell cycle progression can also produce new liabilities for cell survival. To uncover such liabilities in Rb mutant cells, we performed a clonal screen in the Drosophila eye to identify second-site mutations that eliminate Rbf(-) cells, but allow Rbf(+) cells to survive. Here we report the identification of a mutation in a novel highly conserved peptidyl prolyl isomerase (PPIase) that selectively eliminates Rbf(-) cells from the Drosophila eye.

For nearly a century, genetic analysis in Drosophila melanogaster has been a powerful tool for analyzing gene function, yet Drosophila lacks the molecular genetic mapping tools that recently have revolutionized human, mouse, and plant genetics. Here, we describe the systematic characterization of a dense set of molecular markers in Drosophila by using a sequence tagged site-based physical map of the genome. We identify 474 biallelic markers in standard laboratory strains of Drosophila that span the genome. Most of these markers are single nucleotide polymorphisms and sequences for these variants are provided in an accessible format. The average density of the new markers is one per 225 kb on the autosomes and one per megabase on the X chromosome. We include in this survey a set of P-element strains that provide additional use for high-resolution mapping. We show one application of the new markers in a simple set of crosses to map a mutation in the hedgehog gene to an interval of <1 Mb. This new map resource significantly increases the efficiency and resolution of recombination mapping and will be of immediate value to the Drosophila research community.