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Background: Although previous single-center studies report the rate of anaphylaxis for oral food challenges (OFCs) as 9% to 11%, little is known regarding the epidemiology of clinical OFCs across multiple centers in the United States., Objective: To examine the epidemiology, symptoms, and treatment of clinical low-risk OFCs in the nonresearch setting., Methods: Data were obtained from 2008 to 2013 through a physician survey in 5 food allergy centers geographically distributed across the United States. Allergic reaction rates and the association of reaction rates with year, hospital, and demographics were determined using a linear mixed model. Meta-analysis was used to pool the proportion of reactions and anaphylaxis with inverse-variance weights using a random-effects model with exact confidence intervals (CIs)., Results: A total of 6,377 OFCs were performed, and the pooled estimate of anaphylaxis was 2% (95% CI, 1%-3%). The rate of allergic reactions was 14% (95% CI, 13%-16%) and was consistent during the study period (P = .40). Reaction rates ranged from 13% to 33%. Males reacted 16% more frequently than females (95% CI, 4%-37.5%; P = .04). Foods challenged in 2013 varied geographically, with peanut as the most challenged food in the Northeast, Midwest, and West and egg as the most challenged in the South., Conclusion: As the largest national survey of allergic reactions of clinical open OFCs in a nonresearch setting in the United States, this study found that performing clinical nonresearch open low-risk OFCs results in few allergic reactions, with 86% of challenges resulting in no reactions and 98% without anaphylaxis., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Critical limb ischemia is a manifestation of peripheral artery disease that carries significant mortality and morbidity risk in humans, although its genetic determinants remain largely unknown. We previously discovered 2 overlapping quantitative trait loci in mice, Lsq-1 and Civq-1 , that affected limb muscle survival and stroke volume after femoral artery or middle cerebral artery ligation, respectively. Here, we report that a Bag3 variant (Ile81Met) segregates with tissue protection from hind-limb ischemia., Methods: We treated mice with either adeno-associated viruses encoding a control (green fluorescent protein) or 2 BAG3 (Bcl-2-associated athanogene-3) variants, namely Met81 or Ile81, and subjected the mice to hind-limb ischemia., Results: We found that the BAG3 Ile81Met variant in the C57BL/6 (BL6) mouse background segregates with protection from tissue necrosis in a shorter congenic fragment of Lsq-1 (C.B6- Lsq1-3 ). BALB/c mice treated with adeno-associated virus encoding the BL6 BAG3 variant (Ile81; n=25) displayed reduced limb-tissue necrosis and increased limb tissue perfusion compared with Met81- (n=25) or green fluorescent protein- (n=29) expressing animals. BAG3 Ile81 , but not BAG3 Met81 , improved ischemic muscle myopathy and muscle precursor cell differentiation and improved muscle regeneration in a separate, toxin-induced model of injury. Systemic injection of adeno-associated virus-BAG3 Ile81 (n=9), but not BAG3 Met81 (n=10) or green fluorescent protein (n=5), improved ischemic limb blood flow and limb muscle histology and restored muscle function (force production). Compared with BAG3 Met81 , BAG3 Ile81 displayed improved binding to the small heat shock protein (HspB8) in ischemic skeletal muscle cells and enhanced ischemic muscle autophagic flux., Conclusions: Taken together, our data demonstrate that genetic variation in BAG3 plays an important role in the prevention of ischemic tissue necrosis. These results highlight a pathway that preserves tissue survival and muscle function in the setting of ischemia., (© 2017 American Heart Association, Inc.)

Objective: Reduced skeletal muscle mitochondrial function might be a contributing mechanism to the myopathy and activity based limitations that typically plague patients with peripheral arterial disease (PAD). We hypothesized that mitochondrial dysfunction, myofiber atrophy, and muscle contractile deficits are inherently determined by the genetic background of regenerating ischemic mouse skeletal muscle, similar to how patient genetics affect the distribution of disease severity with clinical PAD., Methods: Genetically ischemia protected (C57BL/6) and susceptible (BALB/c) mice underwent either unilateral subacute hind limb ischemia (SLI) or myotoxic injury (cardiotoxin) for 28 days. Limbs were monitored for blood flow and tissue oxygen saturation and tissue was collected for the assessment of histology, muscle contractile force, gene expression, mitochondrial content, and respiratory function., Results: Despite similar tissue O 2 saturation and mitochondrial content between strains, BALB/c mice suffered persistent ischemic myofiber atrophy (55.3% of C57BL/6) and muscle contractile deficits (approximately 25% of C57BL/6 across multiple stimulation frequencies). SLI also reduced BALB/c mitochondrial respiratory capacity, assessed in either isolated mitochondria (58.3% of C57BL/6 at SLI on day (d)7, 59.1% of C57BL/6 at SLI d28 across multiple conditions) or permeabilized myofibers (38.9% of C57BL/6 at SLI d7; 76.2% of C57BL/6 at SLI d28 across multiple conditions). SLI also resulted in decreased calcium retention capacity (56.0% of C57BL/6) in BALB/c mitochondria. Nonischemic cardiotoxin injury revealed similar recovery of myofiber area, contractile force, mitochondrial respiratory capacity, and calcium retention between strains., Conclusions: Ischemia-susceptible BALB/c mice suffered persistent muscle atrophy, impaired muscle function, and mitochondrial respiratory deficits during SLI. Interestingly, parental strain susceptibility to myopathy appears specific to regenerative insults including an ischemic component. Our findings indicate that the functional deficits that plague PAD patients could include mitochondrial respiratory deficits genetically inherent to the regenerating muscle myofibers., (Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Background: As the prevalence of food allergy has risen among children and young adults, both in the United States and around the world, investigators have become increasingly aware of the daily emotional toll on patients and their families of living with food allergy., Objective: To review the literature regarding the emotional, social, and financial impact of food allergy on pediatric patients and their families, and to provide evidence-based suggestions for clinicians on how to most effectively address these issues., Methods: A literature search was performed to identify relevant articles related to the emotional, social, and financial impact of food allergy., Results: There is a growing body of literature that demonstrates that living with food allergy adversely affects patients and families in the domains above., Conclusion: Food allergy can significantly impact pediatric patients and their families in all areas of their lives. Clinicians should be aware of these issues when working with these families. Implementing a multidisciplinary approach can help families cope with emotional, social, and financial burdens.

Objective: To evaluate the published medical literature on the prevalence and types of food allergies in South Asia., Data Sources: A PubMed search was performed using the keywords India and food allergy, Asia and food allergy, and South Asia and food allergy for any period. Articles cited in selected studies were reviewed for their appropriateness of inclusion into this review., Study Selections: Publications were included that were original research and fit the topic of food allergy and South Asia. South Asia is defined as region inclusive of India, Pakistan, Bangladesh, and Sri Lanka., Results: A total of 169 articles were initially identified, and 47 were reviewed in detail for inclusion in this review. The primary focus was placed on 10 studies that consisted of case reports of newly reported or documented food allergy, survey studies that investigated food allergy prevalence in specific demographics, and prospective and cross-sectional studies with case controls, all of which investigated food allergy prevalence by allergy testing in a selected population., Conclusion: The medical literature on the prevalence and types of food allergy in South Asia indicates that there is a variety of unusual and unique allergens and an overall low incidence of food allergy. There is also an association of increased food allergy prevalence in individuals who live in metropolitan regions or who migrate to communities that have adopted westernization., (Copyright © 2016 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Patients with type 2 diabetes respond poorly to treatments for peripheral arterial disease (PAD) and are more likely to present with the most severe manifestation of the disease, critical limb ischemia. The underlying mechanisms linking type 2 diabetes and the severity of PAD manifestation are not well understood. We sought to test whether diet-induced mitochondrial dysfunction and oxidative stress would increase the susceptibility of the peripheral limb to hindlimb ischemia (HLI). Six weeks of high-fat diet (HFD) in C57BL/6 mice was insufficient to alter skeletal muscle mitochondrial content and respiratory function or the size of ischemic lesion after HLI, despite reducing blood flow. However, 16 weeks of HFD similarly decreased ischemic limb blood flow, but also exacerbated limb tissue necrosis, increased the myopathic lesion size, reduced muscle regeneration, attenuated muscle function, and exacerbated ischemic mitochondrial dysfunction. Mechanistically, mitochondrial-targeted overexpression of catalase prevented the HFD-induced ischemic limb necrosis, myopathy, and mitochondrial dysfunction, despite no improvement in limb blood flow. These findings demonstrate that skeletal muscle mitochondria are a critical pathological link between type 2 diabetes and PAD. Furthermore, therapeutically targeting mitochondria and oxidant burden is an effective strategy to alleviate tissue loss and ischemic myopathy during PAD., (© 2016 by the American Diabetes Association.)

Critical limb ischemia is a devastating manifestation of peripheral arterial disease with no effective strategies for improving morbidity and mortality outcomes. We tested the hypothesis that cellular mitochondrial function is a key component of limb pathology and that improving mitochondrial function represents a novel paradigm for therapy. BALB/c mice were treated with a therapeutic mitochondrial-targeting peptide (MTP-131) and subjected to limb ischemia (HLI). Compared to vehicle control, MTP-131 rescued limb muscle capillary density and blood flow (64.7±11% of contralateral vs. 39.9±4%), and improved muscle regeneration. MTP-131 also increased electron transport system flux across all conditions at HLI day-7. In vitro, primary muscle cells exposed to experimental ischemia demonstrated markedly reduced (~75%) cellular respiration, which was rescued by MTP-131 during a recovery period. Compared to muscle cells, endothelial cell (HUVEC) respiration was inherently protected from ischemia (~30% reduction), but was also enhanced by MTP-131. These findings demonstrate an important link between ischemic tissue bioenergetics and limb blood flow and indicate that the mitochondria may be a pharmaceutical target for therapeutic intervention during critical limb ischemia., (Copyright © 2016. Published by Elsevier Ltd.)

Critical limb ischemia (CLI) is the most severe clinical presentation of peripheral arterial disease and manifests as chronic limb pain at rest and/or tissue necrosis. Current clinical interventions are largely ineffective and therapeutic angiogenesis based trials have shown little efficacy, highlighting the dire need for new ideas and novel therapeutic approaches. Despite a decade of research related to skeletal muscle as a determinant of morbidity and mortality outcomes in CLI, very little progress has been made toward an effective therapy aimed directly at the muscle myopathies of this disease. Within the muscle cell, mitochondria are well positioned to modulate the ischemic cellular response, as they are the principal sites of cellular energy production and the major regulators of cellular redox charge and cell death. In this mini review, we update the crucial importance of skeletal muscle to CLI pathology and examine the evolving influence of muscle and endothelial cell mitochondria in the complex ischemic microenvironment. Finally, we discuss the novelty of muscle mitochondria as a therapeutic target for ischemic pathology in the context of the complex co-morbidities often associated with CLI.

Recent strategies to treat peripheral arterial disease (PAD) have focused on stem cell based therapies, which are believed to result in local secretion of vascular growth factors. Little is known, however, about the role of ischemic endogenous cells in this context. We hypothesized that ischemic muscle cells (MC) are capable of secreting growth factors that act as potent effectors of the local cellular regenerative environment. Both muscle and endothelial cells (ECs) were subjected to experimental ischemia, and conditioned medium (CM) from each was collected and analyzed to assess myogenic and/or angiogenic potential. In muscle progenitors, mRNA expression of VEGF and its cognate receptors (Nrp1, Flt, Flk) was present and decreased during myotube formation in vitro, and EC CM or VEGF increased myoblast proliferation. Angiopoietin-1 (Ang-1), Tie1, and Tie2 mRNA increased during MC differentiation in vitro. Exogenous Ang-1 enhanced myogenic (MyoD and Myogenin) mRNA in differentiating myoblasts and increased myosin heavy chain protein. Myotube formation was enhanced by MC CM and inhibited by EC CM. Ang-1 protein was present in CM from MCs isolated from both the genetically ischemia-susceptible BALB/c and ischemia-resistant C57BL/6 mouse strains, and chimeric Tie2 receptor trapping in situ ablated Ang-1's myogenic effects in vitro. Ang-1 or MC CM enhanced myotube formation in a mixed isolate of muscle progenitors as well as a myoblast co-culture with pluripotent mesenchymal cells (10T1/2) and this effect was abrogated by viral expression of the extracellular domain of Tie2 (AdsTie2). Furthermore, mesh/tube formation by HUVECs was enhanced by Ang-1 or MC CM and abrogated by Tie2 chimeric receptor trapping. Our results demonstrate the ability of muscle and endothelial cell-derived vascular growth factors, particularly Ang-1, to serve as multi-functional stimuli regulating crosstalk between blood vessels and muscle cells during regeneration from ischemic myopathy.

Allergy to tree nuts has grown widespread among patients, specifically in the pediatric population, in recent years. In this review, we evaluate and summarize the literature specific to development and treatment of tree nut allergy. The cause of tree nut allergy, such as most food allergies, is unknown; there are theories regarding maternal dietary factors as well as sensitization related to cross-reactivity to peanut allergens. The gold standard for the diagnosis of tree nut allergy is the double-blind, placebo-controlled, oral food challenge; however, simpler and more cost-effective diagnostic methods, such as the skin prick test and serum-specific IgE are often used as a supplement for diagnosis. Management of tree nut allergy consists of dietary avoidance and using epinephrine to manage serious allergic reactions. Alternative therapeutic methods, such as oral and sublingual immunotherapy and modification of allergenic proteins are being explored to develop safer, more effective and long-lasting management of tree nut allergy. We comment on the current studies involving risk factors for sensitization, diagnosis and management of tree nut allergy.

A break in periodicity occurs in the actinide series between plutonium and americium as the result of the localization of 5f electrons. The subsequent chemistry of later actinides is thought to closely parallel lanthanides in that bonding is expected to be ionic and complexation should not substantially alter the electronic structure of the metal ions. Here we demonstrate that ligation of californium(III) by a pyridine derivative results in significant deviations in the properties of the resultant complex with respect to that predicted for the free ion. We expand on this by characterizing the americium and curium analogues for comparison, and show that these pronounced effects result from a second transition in periodicity in the actinide series that occurs, in part, because of the stabilization of the divalent oxidation state. The metastability of californium(II) is responsible for many of the unusual properties of californium including the green photoluminescence.

Temperature-dependent photoluminescence of structurally precise Au25(SC8H9)18 and Au38(SC12H25)24 monolayer-protected cluster (MPC) nanoparticles were studied using energy-resolved, intensity-integrated, and time-resolved spectroscopy. Measurements were carried out at sample temperatures spanning the range from 4.5 to 200 K following electronic excitation using 3.1 eV pulsed lasers. The integrated PL intensity for Au25(SC8H9)18 increased sharply by 70% as the sample temperature was increased from 4.5 to 45 K. The PL intensity was statistically invariant for temperatures between 45 and 65 K but was quenched when the sample temperature was raised above 65 K. For both MPC samples, the global PL emission included several components. Each PL component exhibited an increase in emission energy when the sample temperature was increased from 4.5 to 40 K. This unexpected behavior may imply that MPCs in the 1 nm domain have negative expansion coefficients. Quantitative analysis of PL emission energies and peak widths obtained at sample temperatures greater than 45 K indicated MPC nonradiative relaxation dynamics are mediated by coupling to low-frequency vibrations associated with the ligand shell that passivated the nanoclusters, which accounted for the low emission yields at high sample temperatures. Contributions from two different vibrational modes were identified: Au(I)-S stretching (200 cm(-1)) and Au(0)-Au(I) stretching (90 cm(-1)). Analysis of each PL component revealed that the magnitude of electronic-vibration coupling was state-specific, and consistently larger for the high-energy portions of the PL spectra. The total integrated PL intensity of the Au25(SC8H9)18 MPC was correlated to the relative branching ratios of the emission components, which confirmed decreased emission for recombination channels associated with strong electron-vibration coupling and high emission yields for low emission energies at low temperature. The efficient low-energy emission was attributed to a charge-transfer PL transition. This conclusion was reached based on the strong correlation between temperature-dependent intensity-integrated and time-resolved emission measurements that revealed an ∼3.5-5.5 meV activation barrier to nonradiative decay. These findings suggest that nanoscale structure and composition can be modified to tailor the optical and mechanical properties and electronic relaxation dynamics of MPC nanostructures.

The participation of the valence orbitals of actinides in bonding has been debated for decades. Recent experimental and computational investigations demonstrated the involvement of 6p, 6d and/or 5f orbitals in bonding. However, structural and spectroscopic data, as well as theory, indicate a decrease in covalency across the actinide series, and the evidence points to highly ionic, lanthanide-like bonding for late actinides. Here we show that chemical differentiation between californium and lanthanides can be achieved by using ligands that are both highly polarizable and substantially rearrange on complexation. A ligand that suits both of these desired properties is polyborate. We demonstrate that the 5f, 6d and 7p orbitals are all involved in bonding in a Cf(III) borate, and that large crystal-field effects are present. Synthetic, structural and spectroscopic data are complemented by quantum mechanical calculations to support these observations.

Background: To evaluate the effects of an amino acid-based formula (AAF) with synbiotics on growth and tolerance in healthy infants. The hypoallergenicity of this AAF with synbiotics was evaluated in subjects with cow's milk allergy (CMA)., Methods: Study 1: 115 full-term, healthy infants randomly received an AAF with synbiotics or a commercially available AAF for 16 wk. Subjects' weight, length, and head circumference were primary outcome measures. Stool characteristics and gastrointestinal (GI) symptoms were secondary outcome measures. Clinical examinations, dietary intake, clinical laboratory results, and adverse events were recorded. Study 2: hypoallergenicity of the AAF with synbiotics was evaluated in 30 infants and children with immunoglobulin E (IgE)-mediated CMA using a double-blind, placebo-controlled food challenge, and a 7-d feeding period., Results: Study 1: comparable results in growth parameters and tolerance were observed for both groups. Minimal differences were observed in stool characteristics and GI symptoms throughout the study. Study 2: all 30 subjects with IgE-mediated CMA completed the study with no allergic reactions detected to challenges., Conclusion: These studies demonstrate that an AAF with synbiotics is safe and well tolerated and promotes normal growth when fed to healthy full-term infants as the sole source of nutrition and is hypoallergenic in subjects with CMA.

Chronic granulomatous disease (CGD) is a rare inherited immunodeficiency syndrome that results from abnormal nicotinamide adenine dinucleotide phosphate (NADPH) oxidase function. This defect leads to recurrent catalase-positive bacterial and fungal infections as well as associated granuloma formation. We review the case of a 2-year-old boy who presented with ascites and fever of an unknown origin as manifestations of CGD. Cultures were negative for infection throughout his course, and CGD was suspected after identification of granulomas on peritoneal biopsy. Genetic testing revealed a novel mutation in the CYBB gene underlying his condition. This paper highlights the importance of considering CGD in the differential diagnosis of fever of unknown origin and ascites in children.

A role for MARCKS protein in directed migration of macrophages toward a chemoattractant was investigated. A peptide identical to the N-terminus of MARCKS (the MANS peptide), shown previously to inhibit the function of MARCKS in various cell types, was used. We investigated whether this MARCKS-related peptide could affect migration of macrophages, using the mouse macrophage-like J774A.1 cell line and primary murine macrophages. Both of these cell types migrated in response to the chemoattractants macrophage/MCPs, MCP-1 (25-100 ng/ml) or C5a (5-20 ng/ml). Cells were preincubated (15 min) with MANS or a mis-sense control peptide (RNS), both at 50 μM, and effects on migration determined 3 h after addition of chemoattractants. The movement and interactions of MARCKS and actin also were followed visually via confocal microscopy using a fluorescently labeled antibody to MARCKS and fluorescently tagged phalloidin to identify actin. MANS, but not RNS, attenuated migration of J774A.1 cells and primary macrophages in response to MCP-1 or C5a, implicating MARCKS in the cellular mechanism of directed migration. Exposure of cells to MCP-1 resulted in rapid phosphorylation and translocation of MARCKS from plasma membrane to cytosol, whereas actin appeared to spread through the cell and into cell protrusions; there was visual and biochemical evidence of a transient interaction between MARCKS and actin during the process of migration. These results suggest that MARCKS is involved in directed migration of macrophages via a process involving its phosphorylation, cytoplasmic translocation, and interaction with actin.

Background: Initial food-allergic reactions are often poorly recognized and under-treated., Methods: Parents of food-allergic children were invited to complete an online questionnaire, designed with Kids with Food Allergies Foundation, about their children's first food-allergic reactions resulting in urgent medical evaluation., Results: Among 1361 reactions, 76% (95% CI 74-79%) were highly likely to represent anaphylaxis based on NIAID/FAAN criteria. Only 34% (95% CI 31-37%) of these were administered epinephrine. In 56% of these, epinephrine was administered by emergency departments; 20% by parents; 9% by paramedics; 8% by primary care physicians; and 6% by urgent care centers. In 26% of these, epinephrine was given within 15 min of the onset of symptoms; 54% within 30 min; 82% within 1 h; and 93% within 2 h. Factors associated with a decreased likelihood of receiving epinephrine for anaphylaxis included age <12 months, milk and egg triggers, and symptoms of abdominal pain and/or diarrhea. Epinephrine was more likely to be given to asthmatic children and children with peanut or tree nut ingestion prior to event. Post-treatment, 42% of reactions likely to represent anaphylaxis were referred to allergists, 34% prescribed and/or given epinephrine auto-injectors, 17% trained to use epinephrine auto-injectors, and 19% given emergency action plans. Of patients treated with epinephrine, only half (47%) were prescribed epinephrine auto-injectors., Conclusions: Only one-third of initial food-allergic reactions with symptoms of anaphylaxis were recognized and treated with epinephrine. Fewer than half of patients were referred to allergists. There is still a need to increase education and awareness about food-induced anaphylaxis., (© 2012 John Wiley & Sons A/S.)

The relaxation dynamics of electronically excited [Au(25)(SR)(18)](q), where q = 0 or -1 and SR = S(CH(2))(2)Ph, were studied using femtosecond time-resolved transient absorption spectroscopy. Nanoclusters excited by 400 nm light were probed using temporally delayed broad-bandwidth continuum probe pulses. Continuum pulses were generated in both the visible and near infrared (NIR) spectral regions, providing access to a wide range of transient spectral features. The use of NIR probe pulses allowed the relaxation dynamics of the excited states located near the HOMO-LUMO energy gap to be monitored in the probe step via the sp ← LUMO and sp ← LUMO+1 transitions. These NIR measurements yielded excited state absorption (ESA) data that were much less congested than the typical visible transient spectrum. For the neutral nanocluster, the time-domain data were composed of three components: (1) a few-picosecond decay, (2) a slower decay taking a few hundred picoseconds and (3) a non-decaying plateau function. Component 1 reflected energy relaxation to semi-ring ligand states; component 2 was attributed to relaxation via a manifold of states located near the HOMO-LUMO energy gap. Component 3 arose from slow radiative recombination. The dynamics of the anion depended upon the identity of the excited state from which the particle was relaxing. The LUMO+1 state of the anion exhibited relaxation dynamics that were similar to those observed for the neutral nanocluster. By comparison, the time-domain data observed for the LUMO state contained only two components: (1) a 3.3 ± 0.2 ps decay and (2) a 5 ± 1 ns decay. The amplitude coefficients of each component were also analyzed. Taken together, the amplitude coefficients and lifetimes were indicative of an activation barrier located approximately 100 meV above the HOMO-LUMO energy gap, which mediated a previously unobserved excited state decay process for [Au(25)(SR)(18)](0). These data suggested that NIR ESA measurements will be instrumental in describing the relaxation processes of quantum-confined nanoclusters.

Background: A major characteristic of asthmatic airways is an increase in mucin (the glycoprotein component of mucus) producing and secreting cells, which leads to increased mucin release that further clogs constricted airways and contributes markedly to airway obstruction and, in the most severe cases, to status asthmaticus. Asthmatic airways show both a hyperplasia and metaplasia of goblet cells, mucin-producing cells in the epithelium; hyperplasia refers to enhanced numbers of goblet cells in larger airways, while metaplasia refers to the appearance of these cells in smaller airways where they normally are not seen. With the number of mucin-producing and secreting cells increased, there is a coincident hypersecretion of mucin which characterizes asthma. On a cellular level, a major regulator of airway mucin secretion in both in vitro and in vivo studies has been shown to be MARCKS (myristoylated alanine-rich C kinase substrate) protein, a ubiquitous substrate of protein kinase C (PKC)., General Significance: In this review, properties of MARCKS and how the protein may regulate mucin secretion at a cellular level will be discussed. In addition, the roles of MARCKS in airway inflammation related to both influx of inflammatory cells into the lung and release of granules containing inflammatory mediators by these cells will be explored. This article is part of a Special Issue entitled: Biochemistry of Asthma., (2010 Elsevier B.V. All rights reserved.)

Background: Cardiac dysfunction is a well-recognized complication of light chain amyloidosis (AL). Autologous stem cell transplant (auto-SCT) has emerged as a successful treatment modality for AL patients. In this study, we examined the effect of clonal immunoglobulin light chain genes (VL), which encodes the immunoglobulin light chain protein that ultimately forms amyloid, on cardiac function, in the context of auto-SCT and its impact on overall survival., Methods: Longitudinal Doppler myocardial imaging parameters along with cardiac biomarkers were used to assess for cardiac function pre and post auto-SCT., Results: VL gene analysis revealed that Vl genes, in particular VlVI, were associated with worse cardiac function parameters than Vk genes. Clonal VL genes appeared to have an impact on left ventricular (LV) function post-transplant and also influenced mortality, with specific VL gene families associated with lower survival. Another key predictor of mortality in this report was change in tricuspid regurgitant flow velocity following auto-SCT. Correlations were also observed between systolic strain rate, systolic strain and VL genes associated with amyloid formation., Conclusions: Clonal VL gene usage influences global cardiac function in AL, with patients having VlVI and VlII-III-associated amyloid more severely affected than those having Vk or VlI amyloid. Pulsed wave tissue Doppler imaging along with immunoglobulin gene analysis offers novel insights into prediction of mortality and cardiac dysfunction in AL after auto-SCT., (Copyright © 2011 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.)

The immunologic interactions in the gastrointestinal tract are extensive and complex. In most cases, the end result of this activity is one of tolerance, which refers to the inhibition of an immune response. However, in a minority of cases, food allergy develops, and this seems to be increasing in prevalence. We continue to learn about the mechanisms involved in these processes and the factors that may promote tolerance as opposed to allergy. At this point, management of food allergy consists of allergen avoidance and readiness to manage an accidental exposure reaction, but using current knowledge of gastrointestinal immunity, researchers are investigating immunomodulatory approaches that will provide "active" therapy for food allergy and induce tolerance. Oral immunotherapy is one important therapy being studied, and in this article, we review recent results from studies of this potential treatment for food allergy.

Objective: The goal was to determine whether patients seen in a referral clinic are experiencing initial allergic reactions to peanuts earlier, compared with a similar population profiled at a different medical center 10 years ago, and to investigate other changes in clinical characteristics of the patients between the 2 groups., Methods: We reviewed the medical charts of peanut-allergic patients seen in the Duke University pediatric allergy and immunology clinic between July 2000 and April 2006., Results: The median ages of first peanut exposure and reaction were 14 and 18 months, respectively; the respective ages in a similar population profiled between 1995 and 1997 were 22 and 24 months. Within our patient group, those born before 2000 were first exposed to peanuts at a median age of 19 months and reacted at a median age of 21 months, compared with first exposure at 12 months and first reaction at 14 months for those born in or after 2000. Most patients (68%) demonstrated sensitization or clinical allergy to other foods (53% to eggs, 26% to cow's milk, 20% to tree nuts, 11% to fish, 9% to shellfish, 7% to soy, 6% to wheat, and 6% to sesame seeds)., Conclusions: In the past decade, the ages of first peanut exposure and reaction have declined among peanut-allergic children seen in a referral clinic. Egg allergy is very common in peanut-allergic patients, and sesame seeds should perhaps be considered one of the major food allergens. The decline in the age of first peanut reaction seems to be attributable to earlier exposure.

The persistence of transplacentally transferred maternal T cells is common in infants with severe combined immunodeficiency (SCID), occurring in more than half of patients with SCID undergoing transplantation at our institution. These T cells respond poorly to mitogens in vitro but can cause cutaneous graft-versus-host disease; however, other effects of these cells are unknown. We describe 2 infants with SCID who had unusual problems associated with transplacentally transferred maternal T cells. Patient 1 was a 5-month-old girl with Janus kinase 3-deficient SCID who had 4% circulating CD3(+) T cells but no lymphocyte proliferative response to mitogens. Although the number of T cells increased after 2 nonchemoablated, T cell-depleted, haploidentical, paternal bone marrow transplantations, T-cell function failed to develop, and she became pancytopenic. Restriction fragment length polymorphism studies of flow cytometry-sorted blood T cells revealed all to be of maternal origin. A subsequent nonchemoablated, T cell-depleted maternal transplantation resulted in normal T-cell function and marrow recovery. Patient 2 was a 9-month-old girl with IL-7Ralpha-deficient SCID who presented with autoimmune pancytopenia. She had 8% blood T cells (all CD45RO(+)) but no response to mitogens. High-resolution HLA sequence-specific priming typing detected both maternal haplotypes, indicating the presence of maternal cells. Her pancytopenia resolved after treatment with rituximab and was thought to be due to host B-cell activation by transplacentally acquired maternal T cells. Persistent transplacentally acquired maternal T cells in infants with SCID can mediate immunologic functions despite failing to respond to mitogens in vitro. We present evidence that these cells can cause allograft rejection and immune cytopenias.

Background: There is no current active treatment for food allergy. Traditional injection immunotherapy has been proved unsafe, and thus there is a need for other forms of immunotherapy., Objective: The purpose was to study the safety and immunologic effects of egg oral immunotherapy (OIT). The short-term goal was to desensitize subjects to protect against accidental ingestion reactions. The eventual goal was to induce lasting clinical and immunologic tolerance., Methods: Subjects with a history of egg allergy but without a history of anaphylaxis to egg underwent a 24-month egg OIT protocol involving modified rush, build-up, and maintenance phases. Double-blind, placebo-controlled food challenges were performed at study conclusion. Egg-specific IgE and IgG concentrations were followed., Results: Seven subjects completed the protocol. Egg-specific IgG concentrations increased significantly, whereas egg-specific IgE concentrations did not significantly change. Three subjects tolerated known or possible accidental egg ingestions while receiving OIT. During double-blind, placebo-controlled food challenges at study conclusion, all tolerated significantly more egg protein than at study onset and than that found in the typical accidental exposure. Two subjects demonstrated oral tolerance., Conclusion: This study provides proof of concept that OIT can be safely used for patients with egg allergy without a history of anaphylaxis to egg. Egg OIT does not heighten sensitivity to egg and might protect against reaction on accidental ingestion. Whether OIT will induce clinical oral tolerance cannot be concluded from this initial cohort., Clinical Implications: Use of allergen-specific OIT to protect subjects with food allergy from reaction on accidental ingestion would represent a significant paradigm change in the treatment of food allergy.

Left atrial (LA) enlargement, left ventricular (LV) diastolic dysfunction, and increased arterial stiffness are all associated with adverse cardiovascular outcomes. The rate, magnitude, and concordance of modifiability of these risk markers have not been well characterized. Twenty-one patients (mean age 69 +/- 8 years; 52% women) with isolated diastolic dysfunction and indexed LA volumes > or =32 ml/m(2) were randomly assigned to receive either quinapril at a target dose of 60 mg/day or matching placebo for 12 months. Echocardiographic maximum LA volume and LV diastolic function and arterial stiffness by the augmentation index were measured at baseline and 6 and 12 months. Analysis was based on intention to treat. Baseline characteristics were comparable between the treatment (n = 9) and placebo (n = 12) groups. The mean reduction in LA volume of 4.2 +/- 7.8 ml/m(2) in the quinapril group was significant (p = 0.01) compared with the increase in LA volume in the placebo group (5.5 +/- 8.1 ml/m(2)). This represents a relative improvement of 9.7 ml/m(2). Change in LV filling pressure in terms of E/e' and diastolic function grade did not reach significance. A reduction in the augmentation index was associated with a decrease in indexed LA volume (odds ratio 11, p = 0.046), independent of changes in systolic blood pressure. In conclusion, LA structural remodeling appeared reversible with quinapril, which occurred in parallel with an improvement in arterial stiffness but independent of blood pressure changes.

Mammalian Notch-1 is part of an evolutionarily conserved family of transmembrane receptors best known for involvement in cell fate decisions. Mutations that result in Notch-1 activation result in T-lineage oncogenesis. In other cell lineages, however, studies have indicated that cooperation with cellular signaling pathways, such as Ras, is necessary for Notch-mediated oncogenesis and in some settings, Notch-1 has been reported to function as a tumor suppressor. In order to test the hypothesis that the Notch-1 pathway exhibits cross-talk with Ras/Raf/MEK/ERK, the constitutively active cytoplasmic portion of Notch-1 was introduced into 293 HEK fibroblasts via retroviral transduction. ERK-1,-2 activation was markedly increased in cells expressing constitutively active Notch-1. These cells exhibited a more rounded morphology as compared to 293 cells transduced with an empty vector or parental 293 cells. These observations correlated with decreased total and phosphorylated focal adhesion kinase protein (FAK). Subsequent examination of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) revealed that total and phosphorylated PTEN protein was elevated in cells expressing constitutively active Notch-1. Loss of Akt phosphorylation was also observed in cells bearing activated Notch-1. Two potential binding sites for the Notch effector CBF-1 were identified in the human PTEN promoter sequence. A PTEN promoter luciferase reporter exhibited increased activity in the presence of Notch-1 signaling. These data indicate that Notch-1 can participate in cross-talk with other signaling pathways such as Ras/Raf/MEK/ERK through the regulation of the PTEN tumor suppressor.

B-lineage acute leukemia (B-ALL) cells often require stromal cell support for optimal proliferation and apoptotic resistance. In addition, stromal cell contact can promote resistance to chemotherapeutic agents. However, the precise biochemical pathways within the leukemic cell that are activated by the bone marrow microenvironment which result promotion of cell proliferation and apoptotic protection are not fully characterized. We have recently reported that simultaneous inhibition of the MEK and PI3K pathways or the MEK and mTOR pathways promote rapid apoptosis of the stromal cell dependent B-lineage ALL cell line BLIN-2 in the presence of stromal cell support. These data indicated that stromal cell induced apoptotic protection is mediated by PI3K/mTOR and MEK in a mechanism(s) that suggests cross-talk or points of convergence. The EGF receptor (EGFR) has been reported to activate both MEK and PI3K. We report herein that use of the EGFR inhibitor, AG1478, inhibits BLIN-2 survival in the presence of stromal cells. FACS analysis revealed that EGFR is expressed on the surface of BLIN-2 cells. The addition of EGF to BLIN-2 cultures in the absence of stromal cells prolongs BLIN-2 survival. Similarly, introduction of a constitutively active form of EGFR, v-ErbB, into BLIN-2 prolongs the survival of BLIN-2 cells in the absence of stromal cell support. These data provide evidence that stimulation of the EGFR pathway is one mechanism by which the bone marrow microenvironment may contribute to the growth and survival of B-cell acute leukemia.

DNA vaccines expressing the envelope (Env) of the human immunodeficiency virus type 1 (HIV-1) have been relatively ineffective at generating high-titer, long-lasting, neutralizing antibodies. In this study, DNA vaccines were constructed to express the gp120 subunit of Env from the isolate HIV-1(R2) using both wild-type and codon-optimized gene sequences. Three copies of the murine C3d were added to the carboxyl terminus to enhance the immunogenicity of the expressed fusion protein. Mice (BALB/c) vaccinated with DNA plasmid expressing the gp120(R2) using codon-optimized Env sequences elicited high-titer anti-Env antibodies regardless of conjugation to C3d. In contrast, only mice vaccinated with DNA using wild-type gp120(R2) sequences fused to mC3d(3), had detectable anti-Env antibodies. Interestingly, mice vaccinated with DNA expressing gp120(R2) from codon-optimized sequences elicited antibodies that neutralized both homologous and heterologous HIV-1 isolates. To determine if the unique sequence found in the crown of the V3 loop of the Env(R2) was responsible for the elicitation of the cross-clade neutralizing antibodies, the codons encoding for the Pro-Met (amino acids 313-314) were introduced into the sequences encoding the gp120(ADA) (R5) or gp120(89.6) (R5X4). Mice vaccinated with gp120(ADA)-mC3d(3)-DNA with the Pro-Met mutation had antibodies that neutralized HIV-1 infection, but not the gp120(89.6)-mC3d(3)-DNA. Therefore, the use of the unique sequences in the Env(R2) introduced into an R5 tropic envelope, in conjunction with C3d fusion, was effective at broadening the number of viruses that could be neutralized. However, the introduction of this same sequence into an R5X4-tropic envelope was ineffective in eliciting improved cross-clade neutralizing antibodies.

DNA vaccines expressing the envelope (Env) of the human immunodeficiency virus type 1 (HIV-1) have been relatively ineffective at generating high-titer, long-lasting, neutralizing antibodies in a variety of animal models. In this study, DNA vaccines were constructed to express a fusion protein of the soluble human CD4 (sCD4) and the gp120 subunit of the HIV-1 envelope. To enhance the immunogenicity of the expressed fusion protein, three copies of the murine C3d (mC3d3) were added to the carboxyl terminus of the complex. Monoclonal antibodies that recognize CD4-induced epitopes on gp120 efficiently bound to sCD4-gp120 or sCD4-gp120-mC3d3. In addition, both sCD4-gp120 and sCD4-gp120-mC3d3 bound to cells expressing appropriate coreceptors in the absence of cell surface hCD4. Mice (BALB/c) vaccinated with DNA vaccines expressing either gp120-mC3d3 or sCD4-gp120-mC3d3 elicited antibodies that neutralized homologous virus infection. However, the use of sCD4-gp120-mC3d3-DNA elicited the highest titers of neutralizing antibodies that persisted after depletion of anti-hCD4 antibodies. Interestingly, only mice vaccinated with DNA expressing sCD4-gp120-mC3d3 had antibodies that elicited cross-protective neutralizing antibodies. The fusion of sCD4 to the HIV-1 envelope exposes neutralizing epitopes that elicit broad protective immunity when the fusion complex is coupled with the molecular adjuvant, C3d.

This experiment compared the performance with explicit (rule-application and rule-discovery) and implicit (nonrule-instructed) learning approaches on the performance of a probabilistic video game task requiring fine motor control. The task required visual tracking of a small ball of light and "catching" it by means of joystick manipulation. A general pattern of improvement with practice occurred for all conditions. All conditions showed use of predictive relations among stimulus events. However, task performance of the rule-application and rule-discovery conditions were inferior to the nonrule-instructed implicit condition, particularly during the early phases of rule acquisition and application. This pattern strongly suggests substantial performance costs associated with attempting to discover or apply probabilistic rules. Decrements are likely due to increased cognitive demands associated with attempting to remember and strategically apply provided probability rules or attempting to discover and apply potentially important and useful probability information from a complex visual display.

Cross-protection between different subtypes of influenza A virus has been attributed to heterosubtypic immunity (HSI). Although, HSI can occur in the absence of anti-HA or anti-NA antibodies, HSI seems to be mediated, in part, by cross-reactive antibodies. In this study, we examined the effects of a DNA vaccine expressing an influenza HA fused to three copies of murine C3d of complement (HA-mC3d(3)). HA-mC3d(3) elicited heterosubtypic immunity more efficiently than non-fused forms of HA and protected mice from lethal challenge of influenza with different subtypes. Plasmid encoding for various forms of HA were constructed from two influenza strains, A/Puerto Rico/8/34 (H1N1) or A/Aichi/2/68-x31 (H3N2). Vaccinated mice were analyzed for enhancement of anti-HA titers, affinity maturation of antibody, hemagglutinin-inhibition activity, and altered cytokine profiles. The HA-mC3d(3)-DNA vaccinated mice were protected from heterologous influenza challenge, even though sera from these mice had no viral-neutralizing activity against heterologous virus.

DNA vaccines expressing the envelope (Env) protein of the human immunodeficiency virus have been relatively ineffective at generating high-titer, long-lasting, neutralizing antibodies in a variety of animal models. In this study, the murine and human homologues of the complement component, C3d, were used in a DNA vaccine to enhance the titers of antibody to Env. Initially, plasmids expressing a secreted form of Env (sgp120) fused to one, two, or three copies of the murine homologue of C3d (mC3d) were constructed. Mice were inoculated with four vaccinations of DNA or two DNA vaccinations, followed by two boosts of affinity-purified gp120 protein. Analyses of titers demonstrated that multiple copies of mC3d coupled to sgp120 induced long-lasting, high-titer anti-Env antibody. Priming mice with sgp120-mC3d-DNA, followed by inoculation of purified gp120 protein, elicited the strongest antibody titers; however, the avidity maturation of the antibody was accelerated in the mice inoculated with sgp120-mC3d(3)-DNA. In addition, DNAs expressing sgp120 fused to three copies of the human homologue of C3d (hC3d(3)) efficiently enhanced the anti-Env antibody in rabbits. Lastly, antisera from both mice and rabbits vaccinated with DNA expressing sgp120-C3d(3) elicited higher titers of neutralizing antibody than did nonfused forms of Env. These results indicate that C3d, conjugated to sgp120, enhances the antibody responses to Env compared to non-C3d fused forms of Env, and this approach may be one way to overcome the poor ability of DNA vaccines to generate antibodies to Env.

Measles remains a major cause of worldwide infant mortality despite the use of current live attenuated vaccines. New approaches to measles virus (MV) vaccine development are critical to interrupt the spread of MV. In this study, we report the results using a DNA vaccine expressing a fusion of the measles hemagglutinin (H) protein and the complement component, C3d, to enhance the titers of neutralizing antibody. Plasmids were generated that expressed a secreted (s) form of H and the same form fused to three tandem copies of the murine homologue of C3d (sH-3C3d). Analysis of titers of the antibody raised in vaccinated mice indicated that immunizations with the DNA expressing sH-3C3d had higher titers of anti-H antibodies compared to serum from mice vaccinated with DNA expressing sH only. In addition, sH-3C3d elicited higher neutralizing antibody titers that inhibited MV induced plaque formation.

DNA vaccination can elicit both humoral and cellular immune responses and can confer protection against several pathogens. However, DNA vaccines expressing the envelope (Env) protein of human immunodeficiency virus (HIV) have been relatively ineffective at generating high titer, long-lasting, neutralizing antibodies in a variety of animal models. In this study, we report that fusion of Env and the complement component, C3d, in a DNA vaccine, enhances the titers of antibody to Env. Plasmids were generated that expressed a secreted form of Env (sgp120) from three isolates of HIV and these same forms fused to three tandem copies of the murine homologue of C3d (sgp120-3C3d). Analyses of titers and avidity maturation of the raised antibody indicated that immunizations with each of the sgp120-3C3d-expressing DNAs accelerated both the onset and the avidity maturation of antibody to Env.

Speed of response is an important clinical issue in the treatment of depressed elderly patients. Our objective was to compare rapid response rates in a study combining therapeutic sleep deprivation (TSD) with paroxetine with two earlier randomized, double-blind studies in late-life depression, one of paroxetine versus nortriptyline and another of nortriptyline versus placebo. We measured depressive symptoms with the 17-item Hamilton Rating Scale of Depression (HRSD), defining rapid response as an HRSD < or = 10 by 2 weeks. With combination therapy (TSD + paroxetine), 9 of 13 patients (69%) experienced a rapid response. In the nortriptyline versus paroxetine study, nortriptyline brought about rapid response in 12 of 37 (32%) and paroxetine in 11 of 43 patients (26%). In the third study, rapid response to nortriptyline occurred in 10 of 41 patients (24%) and to placebo in 6 of 39 patients (15%). The overall chi square, including the rate of rapid response to placebo, was 14.87 (P = .005). The chi square on the four active treatment groups, excluding placebo, was 10.28 (P = .016). This preliminary observation suggests that combined therapy with TSD plus paroxetine may be twice as successful at achieving rapid response in elderly depressed patients than conventional monotherapy with medication or placebo. A prospective, placebo-controlled evaluation of this dual therapy is warranted.

Predictions derived from cognitive consistency theories, self-esteem theories, and ego-serving-bias theory concerning how students would make attributional and affective responses to their academic performance were investigated. 202 university students completed a measure of self-acceptance of their college ability and made attributional and affective responses to an hypothetical examination performance. Analyses showed that students receiving positive feedback perceived greater internal causality and responded with greater positive affect than students receiving negative feedback. Self-acceptance did not moderate the attributions or affective reactions. The results supported the ego-serving-bias theory and provided partial support for self-esteem theory. Findings did not support predictions from cognitive-consistency theory.

A qualitative, visually interpreted, rapid, and synthetic peptide-based anti-human immunodeficiency virus-1 (HIV) antibody immunoassay has been developed that may be of value in situations in which rapid determination of HIV-1 status is important. Because questions have been raised about the accuracy of rapid anti-HIV-1 assays, the sensitivity, specificity, interobserver and intraobserver variability of the Genie HIV-1 assay (Genetics Systems, Seattle, WA) were determined. Sera from 56 patients with HIV-1 infections documented by enzyme immunoassay and western blot tested positive by this assay. Enzyme immunoassay- and western blot-negative sera from 30 visceral organ transplant donors were negative using the Genie assay. Specificity was examined further by testing sera from 29 patients hospitalized with a variety of medical disorders, including acute bacterial pneumonia, acute myocardial infarction, monoclonal gammopathy, and high titer antinuclear or antimitochondrial antibodies. Two of these patients were reactive with the enzyme immunoassay, both of which tested negative by western blot. All 29 tested negative using the Genie assay. In addition, sera from five patients with repeatedly reactive enzyme immunoassays and negative western blots tested negative by the Genie system. There was 100% agreement in interobserver and intraobserver studies. With the western blot as the reference method, the Genie assay exhibited 100% sensitivity and specificity and there was no observer variability.

We compared the influences of explicit instruction and uninstructed implicit learning of correlations among visual events, in a fine-motor task. The task required visual tracking of a small "ball" of light and "catching" it by means of joystick manipulation. A general pattern of improvement with practice for instructed and "noninstructed" conditions was found. Additionally, both instructed and noninstructed conditions evidenced use of the predictive relationships among stimulus events. The improvement in overall performance caused by explicit verbal instructions was less than the improvement seen with the implicit learning condition. Further, instructed and noninstructed conditions showed different patterns of joystick activity. These findings suggest a qualitatively different approach to visual information processing and task performance for the instructional conditions

The effect of several fungicides on laboratory surfaces contaminated with the culture (spore) phase of aerosolized Blastomyces dermatitidis, Coccidioides immitis, and Histoplasma capsulatum was ascertained. The culture (spore) phase was more resistant to the action of the fungicides than was the tissue (yeast) phase. The addition of a wetting agent increased the efficiency of several fungicides. The time required for disinfection with a given concentration of fungicide, or the concentration required to disinfect within a given time, can be determined by interpolating the plotted graphs.

The effect of several fungicides on laboratory surfaces contaminated with the tissue phase of aerosolized Blastomyces dermatitidis, Coccidioides immitis, Cryptococcus neoformans, and Histoplasma capsulatum was ascertained. A statistical analysis of the data shows the correlation between fungi, surfaces, time, and concentration of disinfectant. All fungicides were effective at established times and concentrations, and the type of contaminated surface affected the fungicidal efficacy. By interpolating plotted graphs, laboratory personnel may determine, with a given fungicide, the concentration and time required to disinfect instruments, pipettes, gloves, bench tops, and floors contaminated with a tissue phase of pathogenic fungi.