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Pre-stressing aluminum (Al) particles by annealing and quenching alters dilatational strain and is linked to increased particle reactivity. The quenching rate associated with pre-stressing is a key parameter affecting the final stress state within the Al particle, with faster quenching rates theoretically favoring a higher, more desirable stress state. Micron scale Al particles are annealed to 573 K, then quenched at different rates (i.e., 200 and 900 K/min), mixed with bismuth oxide (Bi2O3), and the Al + Bi2O3 mixtures are examined under low-velocity, drop-weight impact conditions. Both quenching rates showed increased impact ignition sensitivity (i.e., between 83% and 89% decrease in ignition energy). However, the slower quenching rate showed a 100% increase in pressurization rate compared to untreated particles, while the faster quenching rate showed a 97% increase in peak pressure, indicating that these two quenching rates affect Al particles differently. Surprisingly, synchrotron X-ray diffraction data show that the 200 K/min quenched particles have a higher dilatational strain than the untreated particles or the 900 K/min quenched particles. Results are rationalized with the help of a simple mechanical model that takes into account elastic stresses, creep in the alumina shell, and delamination of shell from the core. The model predicts that Al powder quenched at 200 K/min did not experience delamination. In contrast, Al quenched at 900 K/min did not have creep but does have delamination, and under impact, delamination led to major fracture, greater oxygen access to the core, and significant promotion of reaction. Thus, the increase in quenching rate and shell-core delamination are more important for the increase in Al reactivity than pre-stressing alone.

Micron-scale aluminum (Al) particles are plagued by incomplete combustion that inhibits their reactivity. One approach to improving reactivity is to anneal Al particles to increase dilatational (volumetric) strain which has also been linked to increased combustion performance. While optimal annealing temperatures have been identified (roughly 300 °C), little is known about cooling rate effects on particle combustion performance. This study examines the effect of quenching after annealing Al microparticles to 100, 200 and 300 °C on intra-particle dilatational strain and reactivity. Synchrotron X-ray diffraction analysis of the particles reveals the cooling rates in the range from 0.007 to 0.38 K/s have little effect on the dilatational strain of the aluminum-core, alumina-shell particles. The annealed and quenched Al particles were then combined with a metal oxidizer (copper oxide) to examine reactivity. Flame propagation experiments follow the same trend: flame speeds are unchanged until a critical annealing temperature of 300 °C is reached and performance is maintained for each annealing temperature regardless of cooling rate. These results show that altering the mechanical properties and combustion performance of Al particles is strongly dependent on the annealing temperature and unchanged with variation in cooling rate. The contributions from elastic and plastic deformation mechanisms on strain are also considered and additional experimental results are shown on the microstructure of an Al particle. Focused ion beam milling of an Al particle to electron transparency was combined with transmission electron microscope imaging in order to examine the microstructure of the Al particles. This confirmed that the Al microparticles have a polycrystalline structure shown by grains all exceeding 100 nm in size.

Pertussis, once a serious respiratory disease in children, has recently been identified as a common cause of chronic cough in adults. Military personnel are known to be vulnerable to this disease. After a training barracks exposure to pertussis, routine arrangements for contact prophylaxis with erythromycin failed. This experience is reported here as well as that of our subsequent aggressive attempts using directly observed prophylaxis (DOP) with standard erythromycin regimens. No secondary cases occurred. However, many contacts (35%) could not finish a 14-day course despite DOP, mostly because of nausea (85%) or diarrhea (72%). Seventeen (18%) soldiers missed classes because of erythromycin side effects; five required emergency department visits or hospital admission for the same. Sixteen (17%) soldiers were switched to azithromycin because of side effects; all were able to complete a 14-day course without symptoms. High adherence rates with erythromycin administration using DOP are attainable but may trigger unacceptable toxicities; alternative prophylactic regimens should be considered for active duty personnel. [ABSTRACT FROM AUTHOR]

Background: Pulmonary tuberculosis (PTB) is associated with increased cardiovascular disease (CVD) mortality. However, underlying pathophysiological mechanisms are poorly understood. This systematic review aims to synthesise the evidence on the prevalence of cardiac pathology based on cardiac imaging and circulating biomarkers in patients with PTB., Methods: We systematically searched databases for studies in patients with PTB evaluating cardiac pathology (pericardial effusion or left ventricular dysfunction) on echocardiography; late gadolinium enhancement on cardiac magnetic resonance imaging (CMR); myocardial inflammation on positron-emission tomography (PET); coronary artery stenosis on CT coronary angiography (CTCA); and cardiac troponin (cTn) and/or B-type natriuretic peptides (BNP) assessment., Results: Seven studies were included across 1,333 participants with PTB. Four studies used echocardiography (n = 1,111). The prevalence of pericardial effusion ranged from 14.1-55.9%; and left ventricular systolic impairment from 0-4.25%. One study used CMR and PET-CT (n = 26); and two studies used PET-CT alone (n = 196). The prevalence of pericardial and/or myocardial inflammation ranged from 0.6-21.8%. One study evaluated cTn, Creatine Kinase-MB (CK-MB), and BNP (n = 800), of whom 246 had raised cTn. No study reported cardiac pathology using CTCA., Conclusion: Pericardial effusion is the commonest reported cardiac pathology in PTB. To date, only one study has evaluated cardiac biomarkers and studies evaluating myocardial or coronary disease on advanced imaging remain limited. Our study highlights the paucity of evidence on the presence of cardiac pathology in PTB. Studies are required to determine the prevalence of, and disease mechanisms associated with cardiac pathology among patients with PTB., Competing Interests: The authors have no competing interests to declare., (Copyright: © 2024 The Author(s).)

Sebum from sebaceous glands is a rich source of volatile organic compounds (VOCs) that can readily be sampled non-invasively from the surface of skin. The VOC profiles of sebum can then be used to obtain information regarding different medical conditions including diabetes and Parkinson's Disease. However, the effects of sampling approaches and environmental factors on sebum VOC profiles are not established and the confident attribution of VOCs to disease states needs to be free of extraneous influences such as sampling materials and preparatory conditions. Here, we investigated a more standardised skin swab sampling approach for profiling sebum VOCs from healthy human subjects using thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). Using a standard GC-MS method for the chemical analysis of sebum swabs, a surprisingly high number of VOCs originate from 'blank' medical swab material alone (up to 74 VOCs) and from the ambient environment (up to 29 VOCs) based on control experiments. We found that heat-treatment of medical swabs prior to GC-MS reduced the number of VOCs detected from 'blank' swabs and improved the reproducibility of VOC profiling, however significant VOC absorption can still occur from environmental exposure to ambient air. VOCs identified in 'blank' swabs consisted predominantly of hydrocarbons, esters, and silicon-based compounds and depended strongly on the material used (cotton and polyester-rayon). Environmental VOCs found to absorb to swabs from the ambient air during sampling included 1-butylheptyl-benzene and hexadecanoic acid methyl ester as well as exogenous VOCs such as isopropyl palmitate and isopropyl myristate. In contrast, sebum VOCs consisted primarily of esters, alcohols, ketones, and aldehydes. 23 and 18 VOCs were identified in sebum collected using polyester-rayon and cotton-based medical swabs, respectively, with 14 VOCs common to both swabs. The effect of subject bathing prior to sebum sampling had minimal impact on the VOC profiles. However, individual differences owing to external factors such as skin type, diet, and exercise will likely influence sebum production. This study highlights the importance of using rigorous controls in sebum sampling, and recommendations are provided for future research involving sebum VOC analysis. For example, the use of sebum sample replicates across multiple days, and the use of control swabs during sample collection is required to confirm the origin and reliability of sebum VOCs. It is anticipated that these recommendations in conjunction with a library of well-established VOCs from medical swabs will further strengthen biomarker identification resulting from sebum VOC analysis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The optimal length of family medicine training has been debated since the specialty's inception. Currently there are four residency programs in the United States that require 4 years of training for all residents through participation in the Accreditation Council for Graduate Medical Education Length of Training Pilot. Financing the additional year of training has been perceived as a barrier to broader dissemination of this educational innovation. Utilizing varied approaches, the family medicine residency programs at Middlesex Health, Greater Lawrence Health Center, Oregon Health and Science University, and MidMichigan Medical Center all demonstrated successful implementation of a required 4-year curricular model. Total resident complement increased in all programs, and the number of residents per class increased in half of the programs. All programs maintained or improved their contribution margins to their sponsoring institutions through additional revenue generation from sources including endowment funding, family medicine center professional fees, institutional collaborations, and Health Resources and Services Administration Teaching Health Center funding. Operating expense per resident remained stable or decreased. These findings demonstrate that extension of training in family medicine to 4 years is financially feasible, and can be funded through a variety of models.

Dual Bcl-2/Bcl-x L inhibitors are expected to deliver therapeutic benefit in many haematological and solid malignancies, however, their use is limited by tolerability issues. AZD4320, a potent dual Bcl-2/Bcl-x L inhibitor, has shown good efficacy however had dose limiting cardiovascular toxicity in preclinical species, coupled with challenging physicochemical properties, which prevented its clinical development. Here, we describe the design and development of AZD0466, a drug-dendrimer conjugate, where AZD4320 is chemically conjugated to a PEGylated poly-lysine dendrimer. Mathematical modelling was employed to determine the optimal release rate of the drug from the dendrimer for maximal therapeutic index in terms of preclinical anti-tumour efficacy and cardiovascular tolerability. The optimised candidate is shown to be efficacious and better tolerated in preclinical models compared with AZD4320 alone. The AZD4320-dendrimer conjugate (AZD0466) identified, through mathematical modelling, has resulted in an improved therapeutic index and thus enabled progression of this promising dual Bcl-2/Bcl-x L inhibitor into clinical development.

Coronaviruses (CoVs) are positive-stranded RNA viruses that infect humans and animals. Infection by CoVs such as HCoV-229E, -NL63, -OC43 and -HKU1 leads to the common cold, short lasting rhinitis, cough, sore throat and fever. However, CoVs such as Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV), Middle East Respiratory Syndrome Coronavirus (MERS-CoV), and the newest SARS-CoV-2 (the causative agent of COVID-19) lead to severe and deadly diseases with mortality rates ranging between ~1 to 35% depending on factors such as age and pre-existing conditions. Despite continuous global health threats to humans, there are no approved vaccines or drugs targeting human CoVs, and the recent outbreak of COVID-19 emphasizes an urgent need for therapeutic interventions. Using computational and bioinformatics tools, here we present the feasibility of reported broad-spectrum RNA polymerase inhibitors as anti- SARS-CoV-2 drugs targeting its main RNA polymerase, suggesting that investigational and approved nucleoside RNA polymerase inhibitors have potential as anti-SARS-CoV-2 drugs. However, we note that it is also possible for SARS-CoV-2 to evolve and acquire drug resistance mutations against these nucleoside inhibitors., Competing Interests: K.S. is consultant for the Shift Pharmaceuticals, Overland Park, KS 66211, USA. Other authors declare no conflict of interest.

We report on the synthesis of four poly(2-methyl-2-oxazoline) modified lysine dendrimers with different residual groups or modifications on the dendrimer core, including: amino groups (positive charge), carboxyl groups (negative charge), and two drug molecules, one of which has a high log P. We looked at the in vivo distribution amongst three main liver cell types: hepatocytes, liver sinusoidal endothelial cells (LSECs) and Kupffer cells (KCs) and found differences in cell distribution and uptake concentrations dependent on these residual groups. In particular, the amino-functional polymer showed greater uptake by the hepatocytes whilst the carboxyl-functionalised polymer exhibited greater uptake by KCs and LSECs. These findings provide insight into which professional scavenger cells of the liver remove these types of nanoparticles from the bloodstream and we describe some of the design criteria to consider when creating novel drug delivery systems.

Recently reported HIV-1 capsid (CA) inhibitors GS-CA1 and GS-6207 (an analog of GS-CA1) are first-in-class compounds with long-acting potential. Reportedly, both compounds have greater potency than currently approved anti-HIV drugs. Due to the limited access to experimental data and the compounds themselves, a detailed mechanism of their inhibition is yet to be delineated. Using crystal structures of capsid-hexamers bound to well-studied capsid inhibitor PF74 and molecular modeling, we predict that GS-CA compounds bind in the pocket that is shared by previously reported CA inhibitors and host factors. Additionally, comparative modeling suggests that GS-CA compounds have unique structural features contributing to interactions with capsid. To test their proposed binding mode, we also report the design of a cyclic peptide combining structural units from GS-CA compounds, host factors, and previously reported capsid inhibitors. This peptide (Pep-1) binds CA-hexamer with a docking score comparable to GS-CA compounds. Affinity determination by MicroScale thermophoresis (MST) assays showed that CA binds Pep-1 with a ~7-fold better affinity than well-studied capsid inhibitor PF74, suggesting that it can be developed as a possible CA inhibitor.

An approach for optimizing fuel particle reactivity involves the metallurgical process of pre-stressing. This study examined the effects of pre-stressing on aluminum (Al) particle ignition delay and burn times upon thermal ignition by laser heating. Pre-stressing was by annealing Al powder at 573 K and quenching ranged from slow (i.e., 200 K/min) identified as pre-stressed (PS) Al to fast (i.e., 900 K/min) identified as super quenched (SQ) Al. Synchrotron X-ray Diffraction (XRD) analysis quantified an order of magnitude which increased dilatational strain that resulted from PS Al and SQ Al compared to untreated (UN) Al powder. The results show PS Al particles exhibit reduced ignition delay times resulting from elevated strain that relaxes upon laser heating. SQ Al particles exhibit faster burn times resulting from delamination at the particle core-shell interface that reduces dilatational strain and promotes accelerated diffusion reactions. These results link the mechanical property of strain to reaction mechanisms associated with shell mechanics that explain ignition and burning behavior, and show pre-stressing has the potential to improve particle reactivity.

: The oligomerization of HIV-1 integrase onto DNA is not well understood. Here we show that HIV-1 integrase binds the DNA in biphasic (high-affinity and low-affinity) modes. For HIV-1 subtype B, the high-affinity mode is ∼100-fold greater than the low-affinity mode (Kd.DNA = 37 and 3400 nmol/l, respectively). The Kd.DNA values of patient-derived integrases containing subtype-specific polymorphisms were affected two- to four-fold, suggesting that polymorphisms may have an influence on effective-concentrations of inhibitors, as these inhibitors preferably bind to integrase-DNA complex.

Objective: To assess the reliability and usefulness of an EEG-based brain-computer interface (BCI) for patients with advanced amyotrophic lateral sclerosis (ALS) who used it independently at home for up to 18 months., Methods: Of 42 patients consented, 39 (93%) met the study criteria, and 37 (88%) were assessed for use of the Wadsworth BCI. Nine (21%) could not use the BCI. Of the other 28, 27 (men, age 28-79 years) (64%) had the BCI placed in their homes, and they and their caregivers were trained to use it. Use data were collected by Internet. Periodic visits evaluated BCI benefit and burden and quality of life., Results: Over subsequent months, 12 (29% of the original 42) left the study because of death or rapid disease progression and 6 (14%) left because of decreased interest. Fourteen (33%) completed training and used the BCI independently, mainly for communication. Technical problems were rare. Patient and caregiver ratings indicated that BCI benefit exceeded burden. Quality of life remained stable. Of those not lost to the disease, half completed the study; all but 1 patient kept the BCI for further use., Conclusion: The Wadsworth BCI home system can function reliably and usefully when operated by patients in their homes. BCIs that support communication are at present most suitable for people who are severely disabled but are otherwise in stable health. Improvements in BCI convenience and performance, including some now underway, should increase the number of people who find them useful and the extent to which they are used., (© 2018 American Academy of Neurology.)

Clinical Scenario: Increasing hamstring flexibility through clinical stretching interventions may be an effective means to prevent hamstring injuries. However the most effective method to increase hamstring flexibility has yet to be determined., Clinical Question: For a healthy individual, are proprioceptive neuromuscular facilitation (PNF) stretching programs more effective in immediately improving hamstring flexibility when compared with static stretching programs? Summary of Key Findings: A thorough literature search returned 195 possible studies; 5 studies met the inclusion criteria and were included. Current evidence supports the use of PNF stretching or static stretching programs for increasing hamstring flexibility. However, neither program demonstrated superior effectiveness when examining immediate increases in hamstring flexibility. Clinical Bottom Line: There were consistent findings from multiple low-quality studies that indicate there is no difference in the immediate improvements in hamstring flexibility when comparing PNF stretching programs to static stretching programs in physically active adults. Strength of Recommendation: Grade B evidence exists that PNF and static stretching programs equally increase hamstring flexibility immediately following the stretching program.

α-Synuclein plays a central causative role in Parkinson's disease (PD). Increased expression of the P-type ATPase ion pump PARK9/ATP13A2 suppresses α-Synuclein toxicity in primary neurons. Our data indicate that ATP13A2 encodes a zinc pump; neurospheres from a compound heterozygous ATP13A2(-/-) patient and ATP13A2 knockdown cells are sensitive to zinc, whereas ATP13A2 over-expression in primary neurons confers zinc resistance. Reduced ATP13A2 expression significantly decreased vesicular zinc levels, indicating ATP13A2 facilitates transport of zinc into membrane-bound compartments or vesicles. Endogenous ATP13A2 localized to multi-vesicular bodies (MVBs), a late endosomal compartment located at the convergence point of the endosomal and autophagic pathways. Dysfunction in MVBs can cause a range of detrimental effects including lysosomal dysfunction and impaired delivery of endocytosed proteins/autophagy cargo to the lysosome, both of which have been observed in cells with reduced ATP13A2 function. MVBs also serve as the source of intra-luminal nanovesicles released extracellularly as exosomes that can contain a range of cargoes including α-Synuclein. Elevated ATP13A2 expression reduced intracellular α-Synuclein levels and increased α-Synuclein externalization in exosomes >3-fold whereas ATP13A2 knockdown decreased α-Synuclein externalization. An increased export of exosome-associated α-Synuclein may explain why surviving neurons of the substantia nigra pars compacta in sporadic PD patients were observed to over-express ATP13A2. We propose ATP13A2's modulation of zinc levels in MVBs can regulate the biogenesis of exosomes capable of containing α-Synuclein. Our data indicate that ATP13A2 is the first PD-associated gene involved in exosome biogenesis and indicates a potential neuroprotective role of exosomes in PD.

Removal of the basic piperazine nitrogen atom, introduction of a solubilising end group and partial reduction of the triazolopyridazine moiety in the previously-described lead androgen receptor downregulator 6-[4-(4-cyanobenzyl)piperazin-1-yl]-3-(trifluoromethyl)[1,2,4]triazolo[4,3-b]pyridazine (1) addressed hERG and physical property issues, and led to clinical candidate 6-(4-{4-[2-(4-acetylpiperazin-1-yl)ethoxy]phenyl}piperidin-1-yl)-3-(trifluoromethyl)-7,8-dihydro[1,2,4]triazolo[4,3-b]pyridazine (12), designated AZD3514, that is being evaluated in a Phase I clinical trial in patients with castrate-resistant prostate cancer., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

De novo somatic mutations in focal areas are well documented in diseases such as neoplasia but are rarely reported in malformation of the developing brain. Hemimegalencephaly (HME) is characterized by overgrowth of either one of the two cerebral hemispheres. The molecular etiology of HME remains a mystery. The intractable epilepsy that is associated with HME can be relieved by the surgical treatment hemispherectomy, allowing sampling of diseased tissue. Exome sequencing and mass spectrometry analysis in paired brain-blood samples from individuals with HME (n = 20 cases) identified de novo somatic mutations in 30% of affected individuals in the PIK3CA, AKT3 and MTOR genes. A recurrent PIK3CA c.1633G>A mutation was found in four separate cases. Identified mutations were present in 8-40% of sequenced alleles in various brain regions and were associated with increased neuronal S6 protein phosphorylation in the brains of affected individuals, indicating aberrant activation of mammalian target of rapamycin (mTOR) signaling. Thus HME is probably a genetically mosaic disease caused by gain of function in phosphatidylinositol 3-kinase (PI3K)-AKT3-mTOR signaling.

The translation of "next-generation" sequencing directly to the clinic is still being assessed but has the potential for genetic diseases to reduce costs, advance accuracy, and point to unsuspected yet treatable conditions. To study its capability in the clinic, we performed whole-exome sequencing in 118 probands with a diagnosis of a pediatric-onset neurodevelopmental disease in which most known causes had been excluded. Twenty-two genes not previously identified as disease-causing were identified in this study (19% of cohort), further establishing exome sequencing as a useful tool for gene discovery. New genes identified included EXOC8 in Joubert syndrome and GFM2 in a patient with microcephaly, simplified gyral pattern, and insulin-dependent diabetes. Exome sequencing uncovered 10 probands (8% of cohort) with mutations in genes known to cause a disease different from the initial diagnosis. Upon further medical evaluation, these mutations were found to account for each proband's disease, leading to a change in diagnosis, some of which led to changes in patient management. Our data provide proof of principle that genomic strategies are useful in clarifying diagnosis in a proportion of patients with neurodevelopmental disorders.

Neighboring genes are often coordinately expressed within cis-regulatory modules, but evidence that nonparalogous genes share functions in mammals is lacking. Here, we report that mutation of either TMEM138 or TMEM216 causes a phenotypically indistinguishable human ciliopathy, Joubert syndrome. Despite a lack of sequence homology, the genes are aligned in a head-to-tail configuration and joined by chromosomal rearrangement at the amphibian-to-reptile evolutionary transition. Expression of the two genes is mediated by a conserved regulatory element in the noncoding intergenic region. Coordinated expression is important for their interdependent cellular role in vesicular transport to primary cilia. Hence, during vertebrate evolution of genes involved in ciliogenesis, nonparalogous genes were arranged to a functional gene cluster with shared regulatory elements.

A frequently noted but largely anecdotal behavioral observation in Williams syndrome (WS) is an increased tendency to approach strangers, yet the basis for this behavior remains unknown. We examined the relationship between affect identification ability and affiliative behavior in participants with WS relative to a neurotypical comparison group. We quantified social behavior from self-judgments of approachability for faces, and from parent/other evaluations of real life. Relative to typical individuals, participants with WS were perceived as more sociable by others, exhibited perceptual deficits in affect identification, and judged faces of strangers as more approachable. In WS, high self-rated willingness to approach strangers was correlated with poor affect identification ability, suggesting that these two findings may be causally related. We suggest that the real-life hypersociability in WS may arise at least in part from abnormal perceptual processing of other people's faces, rather than from an overall bias at the level of behavior. While this did not achieve statistical significance, it provides preliminary evidence to suggest that impaired social-perceptual ability may play a role in increased approachability in WS., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Williams syndrome is a neurological condition associated with high levels of auditory reactivity and emotional expression combined with impaired perception of prosody. Yet, little is currently known about the neural organization of affective auditory processing in individuals with this disorder. The current study examines auditory emotion processing in individuals with Williams syndrome. Hemispheric organization for positive and negative human non-linguistic sound processing was compared in participants with and without the disorder using a dichotic listening paradigm. While controls exhibited an expected right cerebral hemisphere advantage for processing negative sounds, those with Williams syndrome showed the opposite pattern. No differences between the groups emerged for the positive stimuli. The results suggest aberrant processing of negative auditory information in Williams syndrome., (Copyright (c) 2009 Elsevier Ltd. All rights reserved.)

alpha-Synuclein (alpha-syn) is a small lipid-binding protein involved in vesicle trafficking whose function is poorly characterized. It is of great interest to human biology and medicine because alpha-syn dysfunction is associated with several neurodegenerative disorders, including Parkinson's disease (PD). We previously created a yeast model of alpha-syn pathobiology, which established vesicle trafficking as a process that is particularly sensitive to alpha-syn expression. We also uncovered a core group of proteins with diverse activities related to alpha-syn toxicity that is conserved from yeast to mammalian neurons. Here, we report that a yeast strain expressing a somewhat higher level of alpha-syn also exhibits strong defects in mitochondrial function. Unlike our previous strain, genetic suppression of endoplasmic reticulum (ER)-to-Golgi trafficking alone does not suppress alpha-syn toxicity in this strain. In an effort to identify individual compounds that could simultaneously rescue these apparently disparate pathological effects of alpha-syn, we screened a library of 115,000 compounds. We identified a class of small molecules that reduced alpha-syn toxicity at micromolar concentrations in this higher toxicity strain. These compounds reduced the formation of alpha-syn foci, re-established ER-to-Golgi trafficking and ameliorated alpha-syn-mediated damage to mitochondria. They also corrected the toxicity of alpha-syn in nematode neurons and in primary rat neuronal midbrain cultures. Remarkably, the compounds also protected neurons against rotenone-induced toxicity, which has been used to model the mitochondrial defects associated with PD in humans. That single compounds are capable of rescuing the diverse toxicities of alpha-syn in yeast and neurons suggests that they are acting on deeply rooted biological processes that connect these toxicities and have been conserved for a billion years of eukaryotic evolution. Thus, it seems possible to develop novel therapeutic strategies to simultaneously target the multiple pathological features of PD.

The Williams syndrome (WS) cognitive profile is characterized by relative strengths in face processing, an attentional bias towards social stimuli, and an increased affinity and emotional reactivity to music. An audio-visual integration study examined the effects of auditory emotion on visual (social/non-social) affect identification in individuals with WS and typically developing (TD) and developmentally delayed (DD) controls. The social bias in WS was hypothesized to manifest as an increased ability to process social than non-social affect, and a reduced auditory influence in social contexts. The control groups were hypothesized to perform similarly across conditions. The results showed that while participants with WS exhibited indistinguishable performance to TD controls in identifying facial affect, DD controls performed significantly more poorly. The TD group outperformed the WS and DD groups in identifying non-social affect. The results suggest that emotionally evocative music facilitated the ability of participants with WS to process emotional facial expressions. These surprisingly strong facial-processing skills in individuals with WS may have been due to the effects of combining social and music stimuli and to a reduction in anxiety due to the music in particular. Several directions for future research are suggested., (2009 Elsevier Ltd. All rights reserved.)

Parkinson's disease (PD), dementia with Lewy bodies and multiple system atrophy, collectively referred to as synucleinopathies, are associated with a diverse group of genetic and environmental susceptibilities. The best studied of these is PD. alpha-Synuclein (alpha-syn) has a key role in the pathogenesis of both familial and sporadic PD, but evidence linking it to other predisposition factors is limited. Here we report a strong genetic interaction between alpha-syn and the yeast ortholog of the PD-linked gene ATP13A2 (also known as PARK9). Dopaminergic neuron loss caused by alpha-syn overexpression in animal and neuronal PD models is rescued by coexpression of PARK9. Further, knockdown of the ATP13A2 ortholog in Caenorhabditis elegans enhances alpha-syn misfolding. These data provide a direct functional connection between alpha-syn and another PD susceptibility locus. Manganese exposure is an environmental risk factor linked to PD and PD-like syndromes. We discovered that yeast PARK9 helps to protect cells from manganese toxicity, revealing a connection between PD genetics (alpha-syn and PARK9) and an environmental risk factor (PARK9 and manganese). Finally, we show that additional genes from our yeast screen, with diverse functions, are potent modifiers of alpha-syn-induced neuron loss in animals, establishing a diverse, highly conserved interaction network for alpha-syn.

Vascular disrupting agents (VDAs) are able to affect selectively tumour endothelial cell morphology resulting in vessel occlusion and widespread tumour cell necrosis. However, single-agent antitumour activity of VDAs is typically limited, as tumour regrowth occurs rapidly following drug treatment. To improve the therapeutic effectiveness of VDAs, we investigated liposomal targeting using ZD6126 as a model VDA. ZD6126 is a phosphate-prodrug of the tubulin-binding vascular disrupting agent ZD6126 phenol. ZD6126 was encapsulated into long circulating PEG-liposomes for passive targeting and PEG-liposomes conjugated with peptide ligands containing the RGD-motif for active targeting to alpha(v)-integrins on tumour endothelial cells. ZD6126 could be stably encapsulated, and liposomes displayed minimal leakage in vitro (<10% in 3 weeks). In vivo, upon intravenous injection, free ZD6126 was rapidly converted into ZD6126 phenol, which was cleared from the circulation within minutes. In contrast, ZD6126 encapsulated into either RGD-targeted or PEG liposomes showed prolonged blood circulation times (t(1/2)=10 h), and ZD6126 phenol exposure was also prolonged (t(1/2)=8 h). Both liposomal formulations displayed tumour accumulation plus hepatosplenic uptake by local macrophages. The altered pharmacokinetics and tissue distribution profiles of both liposomal ZD6126 formulations resulted both in single-dose and multiple-dose regimes, in improved therapeutic efficacy in established murine B16.F10 melanomas compared with free ZD6126. The passively and actively targeted liposomes showed equal antitumour efficacy, indicating that delivery of ZD6126 to the tumour tissue may suffice to disrupt tumour blood vessels without the need for specific targeting to the tumour endothelium.

One mechanism of bone adaptation is alteration in tissue level material properties. We hypothesized that alteration in the indentation modulus of the alveolar process is an adaptive response to the localized mechanical environment. Forty-eight specimens representing anterior and posterior regions of the maxilla and mandible were obtained from 6 mature male beagle dogs. The indentation properties of the alveolar bone proper and more distant osteonal cortical bone were estimated. The bone types were further divided into 3 regions (coronal, middle, and apical), with 27 indents being made in each region of tooth-supporting bone. There was a significant difference (p < 0.001) in the indentation moduli of the jaws (maxilla/mandible), location (anterior/posterior), and bone type (alveolar bone proper vs. cortical bone). However, statistical interactions exist which preclude the simple interpretation of results. The distribution of relative stiffness provides a better understanding of bone adaptations in the alveolar process.

Bone turnover rates can be altered by metabolic and mechanical demands. Due to the difference in the pattern of loading, we hypothesized that there are differences in bone remodeling rates between the maxillary and mandibular alveolar processes. Furthermore, in a canine model, the alveolar process of teeth that lack contact (e.g., second premolars) would have a different turnover rate than bone supporting teeth with functional contact (e.g., first molars). Six skeletally mature male dogs were given a pair of calcein labels. After sacrifice, specimens representing the anterior and posterior locations of both jaws were prepared for examination by histomorphometric methods to evaluate the bone volume/total volume (BV/TV; %), bone volume (mm2), mineral apposition rate (MAR; microm/day), and bone formation rate (BFR; %/year) in the alveolar process. There were no significant differences (P>0.05) in the BV/TV within the jaws. The bone volume within the alveolar process of the mandible was 2.8-fold greater than in the maxilla. The MAR was not significantly different between the jaws and anteroposterior locations. However, the BFR was significantly (P<0.0001) greater in the mandible than in the maxilla. The anterior location had higher (P=0.002) remodeling than the posterior location in the maxilla but not in the mandible. While there was a greater bone mass and increased remodeling in the mandible, no remodeling gradient in the coronal-apical direction was apparent in the alveolar process. Bone adaptation probably involves a complex interplay of bone turnover, mass, and architecture., (Copyright (c) 2006 Wiley-Liss, Inc.)

Alpha-synuclein (alphaSyn) misfolding is associated with several devastating neurodegenerative disorders, including Parkinson's disease (PD). In yeast cells and in neurons alphaSyn accumulation is cytotoxic, but little is known about its normal function or pathobiology. The earliest defect following alphaSyn expression in yeast was a block in endoplasmic reticulum (ER)-to-Golgi vesicular trafficking. In a genomewide screen, the largest class of toxicity modifiers were proteins functioning at this same step, including the Rab guanosine triphosphatase Ypt1p, which associated with cytoplasmic alphaSyn inclusions. Elevated expression of Rab1, the mammalian YPT1 homolog, protected against alphaSyn-induced dopaminergic neuron loss in animal models of PD. Thus, synucleinopathies may result from disruptions in basic cellular functions that interface with the unique biology of particular neurons to make them especially vulnerable.

Cyclooxygenase-2 (COX-2) and the prostaglandin products generated as a result of COX-2 activity mediate a variety of biological and pathological processes. Scarless healing occurs in fetal skin in the first and second trimesters of development. This scarless healing process is known to proceed without a significant inflammatory response, which appears to be important for the lack of scarring. Because the COX-2 pathway is an integral component of inflammation, we investigated its role in the fetal repair process using a mouse model of scarless fetal wound healing. COX-2 expression in scarless and fibrotic fetal wounds was examined. In addition, the ability of exogenous prostaglandin E(2) to alter scarless fetal healing was evaluated. The results suggest that the COX-2 pathway is involved in scar production in fetal skin and that targeting COX-2 may be useful for limiting scar formation in adult skin.

Pertussis, once a serious respiratory disease in children, has recently been identified as a common cause of chronic cough in adults. Military personnel are known to be vulnerable to this disease. After a training barracks exposure to pertussis, routine arrangements for contact prophylaxis with erythromycin failed. This experience is reported here as well as that of our subsequent aggressive attempts using directly observed prophylaxis (DOP) with standard erythromycin regimens. No secondary cases occurred. However, many contacts (35%) could not finish a 14-day course despite DOP, mostly because of nausea (85%) or diarrhea (72%). Seventeen (18%) soldiers missed classes because of erythromycin side effects; five required emergency department visits or hospital admission for the same. Sixteen (17%) soldiers were switched to azithromycin because of side effects; all were able to complete a 14-day course without symptoms. High adherence rates with erythromycin administration using DOP are attainable but may trigger unacceptable toxicities; alternative prophylactic regimens should be considered for active duty personnel.

The Wilms' tumor suppressor protein WT1 is a transcriptional regulator that plays a key role in the development of the kidneys. The transcriptional activation domain of WT1 is subject to regulation by a suppression region within the N terminus of WT1. Using a functional assay, we provide direct evidence that this requires a transcriptional cosuppressor, which we identify as brain acid soluble protein 1 (BASP1). WT1 and BASP1 associate within the nuclei of cells that naturally express both proteins. BASP1 can confer WT1 cosuppressor activity in transfection assays, and elimination of endogenous BASP1 expression augments transcriptional activation by WT1. BASP1 is present in the developing nephron structures of the embryonic kidney and, coincident with that of WT1, its expression is restricted to the highly specialized podocyte cells of the adult kidney. Taken together, our results show that BASP1 is a WT1-associated factor that can regulate WT1 transcriptional activity.

Heterogeneous receptor-receptor interactions may play a role in intracellular signaling. Accordingly, the interaction of two dissimilar tyrosine kinase receptors, Ron and epidermal growth factor receptor (EGFR) was investigated. The functional interaction of Ron and EGFR in cell scatter and oncogenic transformation was investigated in vivo. Transfection of a dominant negative form of EGFR into human embryonic kidney cells stably expressing Ron (293-Ron) dramatically reduced the scatter response induced by the Ron ligand hepatocyte growth factor-like protein/macrophage stimulating protein (HGFL). The scatter response of the 293-Ron cells was also attenuated by treatment of the cells with the specific EGFR inhibitor AG 1478. Co-transfection of Ron and dominant-negative EGFR, or co-transfection of EGFR and a dominant-negative form of Ron reduced focus formation in NIH/3T3 cells. Western analysis of NIH/3T3 cells overexpressing murine Ron and expressing endogenous levels of EGFR was used to demonstrate that Ron and EGFR co-immunoprecipitate. Stimulation of the cells in vitro with the Ron ligand HGFL or with the EGFR ligand epidermal growth factor (EGF) appeared to induce phosphorylation of both receptors. Co-immunoprecipitation and phosphorylation of phosphatidyl inositol 3-kinase (PI3-K) was also observed. This novel finding of a functional and biochemical interaction between Ron and EGFR suggests that heterologous tyrosine kinase receptor interactions may play a role in cellular processes such as scatter and transformation.

1 Stimulation of adenosine A(1) receptors produced a stimulation of c-fos promoter-regulated gene transcription in Chinese hamster ovary (CHO)-A1 cells expressing the human A(1) receptor. Gene transcription was monitored using a luciferase-based reporter gene (pGL3). 2 This response to the A(1) receptor agonist N(6)-cyclopentyladenosine (CPA) was sensitive to inhibition by pertussis toxin, the MEK-1 inhibitor PD 98059 and by the phosphatidylinositol-3-kinase inhibitors wortmannin and LY 294002. The response was also completely abolished by the protein kinase C (PKC) inhibitor Ro-31-8220. 3 Several isoforms of PKC can be detected in CHO-A1 cells (alpha, delta, epsilon, micro, iota, zeta), but only PKC alpha, PKC delta and PKC were downregulated by prolonged treatment with phorbol ester. The c-fos-regulated luciferase response to A(1) agonists was not, however, inhibited by 24 h pretreatment with the phorbol esters phorbol 12,13-dibutyrate (PDBu). This observation, together with the fact that a significant attenuation (40%) of the c-fos-luciferase response to PDBu and A(1) agonist was produced by low concentrations of the PKC inhibitor Gö 6976 suggests a role for PKC micro. 4 Stimulation of CHO-A1 cells with CPA stimulated the activation of endogenous PKC micro as measured by autophosphorylation. This was rapid, occurred within 1-2 min, but returned to basal levels after 30 min. Furthermore, transient expression of a constitutively active form of PKC micro resulted in a significant increase in c-fos-regulated gene expression. 5 Taken together, these data suggest that PKC micro plays an important role in the ability of the adenosine A(1) receptor to signal to the nucleus.

Endoplasmic reticulum (ER) quality control (ERQC) components retain and degrade misfolded proteins, and our results have found that the degradation of the soluble ERQC substrates CPY* and PrA* but not membrane spanning ERQC substrates requires transport between the ER and Golgi. Stabilization of these misfolded soluble proteins was seen in cells lacking Erv29p, a probable Golgi localized protein that cycles through the ER by means of a di-lysine ER retrieval motif (KKKIY). Cells lacking Erv29p also displayed severely retarded ER exit kinetics for a subset of correctly folded proteins. We suggest that Erv29p is likely involved in cargo loading of a subset of proteins, including soluble misfolded proteins, into vesicles for ER exit. The stabilization of soluble ERQC substrates in both erv29Delta cells and sec mutants blocked in either ER exit (sec12) or vesicle delivery to the Golgi (sec18) suggests that ER-Golgi transport is required for ERQC and reveals a new aspect of the degradative mechanism.

Three previously identified genes from Saccharomyces cerevisiae, VMA12, VMA21, and VMA22, encode proteins localized to the endoplasmic reticulum (ER). These three proteins are required for the biogenesis of a functional vacuolar ATPase (V-ATPase), but are not part of the final enzyme complex. Subcellular fractionation and chemical cross-linking studies have revealed that Vma12p and Vma22p form a stable membrane associated complex. Cross-linking analysis also revealed a direct physical interaction between the Vma12p/Vma22p assembly complex and Vph1p, the 100-kD integral membrane subunit of the V-ATPase. The interaction of the Vma12p/Vma22p complex with Vph1p was transient (half-life of approximately 5 min), reflecting trafficking of this V-ATPase subunit through the ER en route to the vacuolar membrane. Analysis of these protein-protein interactions in ER-blocked sec12 mutant cells indicated that the Vph1p-Vma12p/Vma22p interactions are quite stable when transport of the V-ATPase out of the ER is blocked. Fractionation of solubilized membrane proteins on a density gradient revealed comigration of Vma22p and Vma12p, indicating that they form a complex even in the absence of cross-linker. Vma12p and Vma22p migrated to fractions separate from Vma21p. Loss of Vph1p caused the Vma12p/Vma22p complex to sediment to less dense fractions, consistent with association of Vma12p/ Vma22p with nascent Vph1p in ER membranes. This is the first evidence for a dedicated assembly complex in the ER required for the assembly of an integral membrane protein complex (V-ATPase) as it is transported through the secretory pathway.

Liposomes were prepared from phospholipid mixtures of dipalmitoylphosphatidylcholine (DPPC) and phosphatidylinositol (PI), encapsulating the enzymes glucose oxidase (GO) and GO in combination with horse radish peroxidase (HRP) by both extrusion (VET) and reverse-phase evaporation (REV). The optimum level of PI in DPPC/PI liposomes for targeting to biofilms of the oral bacterium Streptococcus gordonii has been established. The liposomes were characterised in terms of the content and activity of the encapsulated enzymes. The antibacterial activity of these 'reactive' liposomes arising from hydrogen peroxide and oxyacids in the presence of the substrates glucose and iodide ions, after targeting to the biofilms, were measured both as a function of liposome-biofilm incubation time and incubation time with the substrates. Bacterial inhibition increases with both liposome-biofilm and substrate-biofilm incubation time and with the extent of enzyme encapsulation. The reactive liposomes also display antibacterial activity in the presence of saliva. The reactive liposomes have potential value in the context of oral hygiene.

The Saccharomyces cerevisiae vacuolar H(+)-ATPase (V-ATPase) is a multi-subunit complex that can be structurally and functionally divided into peripheral (V1) and integral membrane (V0) sectors. The vma22-1 mutation was isolated in a screen for mutants defective in V-ATPase function vma22 delta cells contain no V-ATPase activity due to a failure to assemble the enzyme complex; V1 subunits accumulate in the cytosol, and the V0 100-kDa subunit is rapidly degraded. Turnover of the 100-kDa integral membrane protein was found to occur in the endoplasmic reticulum (ER) of vma22 delta cells. The product of the VMA22 gene, Vma22p, is a 21-kDa hydrophilic protein that is not a subunit of the V-ATPase but rather is associated with ER membranes. The association of Vma22p with ER membranes was perturbed by mutations in VMA12, a gene that encodes an ER membrane protein (Vma12p) that is also required for V-ATPase assembly. These results indicate that Vma22p, along with Vma21p and Vma12p, form a set of ER proteins required for V-ATPase assembly.

The isolated Saccharomyces cerevisiae vacuolar proton-translocating ATPase (V-ATPase) is composed of at least 10 subunits. We have identified VMA8, the gene encoding the 32-kDa subunit of the V-ATPase, by 100% match between the sequences of tryptic peptides and the predicted protein sequence of ORF11. The VMA8 gene contains a 768-base pair open reading frame encoding a 256-amino acid protein with a predicted molecular mass of 29,176 Da. Disruption of VMA8 resulted in a mutant exhibiting pH-sensitive growth, slowed growth under all conditions, and an inability to grow on nonfermentable carbon sources. Vacuolar membranes isolated from vma8 delta yeast cells exhibited no V-ATPase activity. Immunoblot analysis of vma8 delta cells revealed normal levels of both V1 and Vo subunits. Whereas the V1 subunits failed to associated with the vacuolar membrane in vma8 delta cells, the Vo polypeptides were transported to and stable in the vacuolar membrane. Density gradient fractionation revealed that Vma8p associated only with the fully assembled V-ATPase and did not associate with a separate lower density Vo subcomplex fraction. Finally, Vma8p was unable to assemble onto the vascular membranes in the absence of other V1 subunits.

Phospholipid liposomes have been prepared from phospholipid mixtures including dipalmitoylphosphatidylcholine/phosphatidylinositol (DPPC/PI) and DPPC/dipalmitoylphosphatidylglycerol (DPPC/DPPG) mixtures and targeted to adsorbed biofilms of the skin-associated bacteria Staphylococcus epidermidis and Proteus vulgaris and the oral bacterium Streptococcus sanguis. The effects of time, liposome concentration and density of bacteria in the biofilm have been studied in detail for Staphylococcus epidermidis. The targeting (as assessed by the apparent monolayer coverage of the biofilms by liposomes) to the biofilms was found to be sensitive to the mol% of PI and DPPG in the liposomes and optimum levels of PI were found for targeting to each bacterium. The use of PI and DPPG-containing liposomes for the delivery of the bactericide, Triclosan, to biofilms of Staphylococcus epidermidis was studied as a function of the amount of Triclosan carried by the liposomes. All the liposome systems tested inhibited the growth of bacteria from the biofilms after brief (2 min) exposure to Triclosan-carrying liposomes. At low Triclosan levels bacterial growth inhibition by Triclosan-carrying liposomes exceeded that by an equivalent level of free Triclosan. After short periods (min) of exposure of biofilms to Triclosan-carrying liposomes the bactericide was shown to preferentially concentrate in the biofilms relative to its liposomal lipid carrier. The results suggest that phospholipid liposomes with appropriately chosen lipid composition have potential for the targeting and delivery of bactericide to bacteria.

The Saccharomyces cerevisiae vacuolar proton-translocating ATPase (V-ATPase) is composed of at least 10 subunits belonging to either the peripheral V1 or integral membrane V0 subcomplex. We have characterized a novel 14-kDa V-ATPase subunit (Vma7p), encoded by the VMA7 gene, which exhibits features common to both V1 and V0 subunit proteins. Vma7p is a hydrophilic protein of 118 amino acids with a predicted molecular mass of 13,452 Da. Vacuolar membranes isolated from a vma7 delta null mutant contained no V-ATPase activity. Western analysis of vma7 delta cells revealed greatly reduced levels of the remaining V0 complex V-ATPase subunits, but normal levels of the V1 subunits. However, the V1 subunits failed to associate with the vacuolar membrane. Unlike the integral membrane subunits of the V0 complex, Vma7p was easily stripped from vacuolar membranes. Density gradient fractionation revealed that Vma7p associated only with the fully assembled V-ATPase and did not associate with a separate lower density V0 subcomplex fraction. The unique properties of the Vma7p may reflect a critical role in stabilizing the V0 complex and bridging the V1 and V0 complexes to form a functional V-ATPase complex.

The yeast vacuolar proton-translocating ATPase (V-ATPase) is a multisubunit complex comprised of peripheral membrane subunits involved in ATP hydrolysis and integral membrane subunits involved in proton pumping. The yeast vma21 mutant was isolated from a screen to identify mutants defective in V-ATPase function. vma21 mutants fail to assemble the V-ATPase complex onto the vacuolar membrane: peripheral subunits accumulate in the cytosol and the 100-kDa integral membrane subunit is rapidly degraded. The product of the VMA21 gene (Vma21p) is an 8.5-kDa integral membrane protein that is not a subunit of the purified V-ATPase complex but instead resides in the endoplasmic reticulum. Vma21p contains a dilysine motif at the carboxy terminus, and mutation of these lysine residues abolishes retention in the endoplasmic reticulum and results in delivery of Vma21p to the vacuole, the default compartment for yeast membrane proteins. Our findings suggest that Vma21p is required for assembly of the integral membrane sector of the V-ATPase in the endoplasmic reticulum and that the unassembled 100-kDa integral membrane subunit present in delta vma21 cells is rapidly degraded by nonvacuolar proteases.

Phospholipid (dipalmitoylphosphatidylcholine (DPPC) plus phosphatidylinositol (PI)) proteoliposomes with surface bound lectins (succinylated concanavalin A (s con A) and wheat germ agglutinin (WGA)) have been prepared covering a range of size and surface density of lectin. Negatively charged phospholipid liposomes from DPPC-PI mixtures covering a range of PI mole % and positively charged liposomes from DPPC-cholesterol-stearylamine (SA) mixtures covering a range of SA mole % have been prepared. The targeting of the liposomes and proteoliposomes to a range of oral and skin-associated been prepared. The targeting of the liposomes and proteoliposomes to a range of oral and skin-associated bacterial biofilms has been investigated. The oral bacteria Streptococcus mutans and gordonii and the skin-associated bacterium Coryneform hofmanni can be targeted with s con A bearing proteoliposomes while the skin associated bacterium Staphylococcus epidermidis can be targeted with WGA bearing proteoliposomes. Both oral and skin-associated bacteria can be targeted with positively charged liposomes although the extents of adsorption to the biofilm are low except for Staphylococcus epidermidis. In the case of negatively charged liposomes targeting is critically dependent on the PI content of the liposomes and for all the bacteria studied optimum levels PI for targeting have been found. The adsorption of the oral bacterium Streptococcus gordonii to immobilised monolayers having the optimum PI level for adsorption has been studied by total internal reflection microscopy (TIRM). Both the phospholipid and proteoliposomes have been used to deliver the bactericide Triclosan to biofilms. All the systems studied inhibited bacterial growth to varying degrees.(ABSTRACT TRUNCATED AT 250 WORDS)