NEDD4L intramolecular interactions regulate its auto and substrate NaV1.5 ubiquitination

NEDD4L is a HECT-type E3 ligase that catalyzes the addition of ubiquitin to intracellular substrates such as the cardiac voltage-gated sodium channel, NaV1.5. The intramolecular interactions of NEDD4L regulate its enzymatic activity which is essential for proteostasis. For NaV1.5, this process is critical as alterations in Na+ current is involved in cardiac diseases including arrhythmias and heart failure. In this study, we perform extensive biochemical and functional analyses that implicate the C2 domain and the first WW-linker (1,2-linker) in the autoregulatory mechanism of NEDD4L. Through in vitro and electrophysiological experiments, the NEDD4L 1,2-linker was determined to be important in substrate ubiquitination of NaV1.5. We establish the preferred sites of ubiquitination of NEDD4L to be in the second WW-linker (2,3-linker). Interestingly, NEDD4L ubiquitinates the cytoplasmic linker between the first and second transmembrane domains of the channel (DI-DII) of NaV1.5. Moreover, we design a genetically encoded modulator of Nav1.5 that achieves Na+ current reduction using the NEDD4L HECT domain as cargo of a NaV1.5-binding nanobody. These investigations elucidate the mechanisms regulating the NEDD4 family and furnish a new molecular framework for understanding NaV1.5 ubiquitination.

Proteomic changes in the hippocampus of large mammals after total-body low dose radiation

There is a growing interest in low dose radiation (LDR) to counteract neurodegeneration. However, LDR effects on normal brain have not been completely explored yet. Recent analyses showed that LDR exposure to normal brain tissue causes expression level changes of different proteins including neurodegeneration-associated proteins. We assessed the proteomic changes occurring in radiated vs. sham normal swine brains. Due to its involvement in various neurodegenerative processes, including those associated with cognitive changes after high dose radiation exposure, we focused on the hippocampus first. We observed significant proteomic changes in the hippocampus of radiated vs. sham swine after LDR (1.79Gy). Mass spectrometry results showed 190 up-regulated and 120 down-regulated proteins after LDR. Western blotting analyses confirmed increased levels of TPM1, TPM4, PCP4 and NPY (all proteins decreased in various neurodegenerative processes, with NPY and PCP4 known to be neuroprotective) in radiated vs. sham swine. These data support the use of LDR as a potential beneficial tool to interfere with neurodegenerative processes and perhaps other brain-related disorders, including behavioral disorders.

Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

Proteomic Changes in the Hippocampus after Repeated Explosive-Driven Blasts

Repeated blast-traumatic brain injury (blast-TBI) has been hypothesized to cause persistent and unusual neurological and psychiatric symptoms in service members returning from war zones. Blast-wave primary effects have been supposed to induce damage and molecular alterations in the brain. However, the mechanisms through which the primary effect of an explosive-driven blast wave generate brain lesions and induce brain consequences are incompletely known. Prior findings from rat brains exposed to two consecutive explosive-driven blasts showed molecular changes (hyperphosphorylated-Tau, AQP4, S100β, PDGF, and DNA-polymerase-β) that varied in magnitude and direction across different brain regions. We aimed to compare, in an unbiased manner, the proteomic profile in the hippocampus of double blast vs sham rats using mass spectrometry (MS). Data showed differences in up- and down-regulation for protein abundances in the hippocampus of double blast vs sham rats. Tandem mass tag (TMT)-MS results showed 136 up-regulated and 94 down-regulated proteins between the two groups (10.25345/C52B8VP0X). These TMT-MS findings revealed changes never described before in blast studies, such as increases in MAGI3, a scaffolding protein at cell-cell junctions, which were confirmed by Western blotting analyses. Due to the absence of behavioral and obvious histopathological changes as described in our previous publications, these proteomic data further support the existence of an asymptomatic blast-induced molecular altered status (ABIMAS) associated with specific protein changes in the hippocampus of rats repeatedly expsosed to blast waves generated by explosive-driven detonations.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Investigation of the association between gall bladder wall thickness and hypoalbuminaemia in dogs

OBJECTIVES

To assess the correlation between gallbladder wall thickness and serum/plasma albumin concentrations in dogs.

MATERIALS AND METHODS

Retrospective searches of digital medical record databases were conducted to identify dogs that had either severely low serum/plasma albumin concentration (<1.5 g/dL) or ultrasonographic evidence of gallbladder wall thickening (>2 mm). Analysis of covariance models were used to analyze gallbladder wall thickness with sample type (serum vs plasma), age, etiology, albumin, and albumin ' etiology as the covariates.

RESULTS

A total of 216 dogs met inclusion criteria. One-hundred and forty-six dogs had a thickened gallbladder wall (Group 1). Median serum/plasma albumin concentration for dogs in this group was 2.2 g/dL (1 to 5 g/dL), and 84 dogs (57.5%) had hypoalbuminemia (<2.5 g/dL). The search for dogs with severe hypoalbuminemia (< 1.5 g/dL) identified 70 dogs (Group 2). In this group, median gallbladder wall thickness was 1.3 mm (0.2 to 6.1 mm) and 17 dogs (24.3%) had a thickened gallbladder wall. Serum/plasma albumin concentration and gallbladder wall thickness were not significantly correlated for Group 1 (r = 0.0044, p = 0.9580) or Group 2 (r = -0.1137, p = 0.3487). A moderate negative correlation (-0.64) was identified between gallbladder wall thickness and albumin concentration in dogs with immune-mediated diseases (p = 0.03).

CLINICAL SIGNIFICANCE

Gallbladder wall thickness and serum/plasma albumin concentration are independent variables in dogs.

Tumour biomarkers: association with heart failure outcomes

BACKGROUND

There is increasing recognition that heart failure (HF) and cancer are conditions with a number of shared characteristics.

OBJECTIVES

To explore the association between tumour biomarkers and HF outcomes.

METHODS

In 2,079 patients of BIOSTAT-CHF cohort, we measured six established tumour biomarkers: CA125, CA15-3, CA19-9, CEA, CYFRA 21-1 and AFP.

RESULTS

During a median follow-up of 21 months, 555 (27%) patients reached the primary end-point of all-cause mortality. CA125, CYFRA 21-1, CEA and CA19-9 levels were positively correlated with NT-proBNP quartiles (all P < 0.001, P for trend < 0.001) and were, respectively, associated with a hazard ratio of 1.17 (95% CI 1.12-1.23; P < 0.0001), 1.45 (95% CI 1.30-1.61; P < 0.0001), 1.19 (95% CI 1.09-1.30; P = 0.006) and 1.10 (95% CI 1.05-1.16; P < 0.001) for all-cause mortality after correction for BIOSTAT risk model (age, BUN, NT-proBNP, haemoglobin and beta blocker). All tumour biomarkers (except AFP) had significant associations with secondary end-points (composite of all-cause mortality and HF hospitalization, HF hospitalization, cardiovascular (CV) mortality and non-CV mortality). ROC curves showed the AUC of CYFRA 21-1 (0.64) had a noninferior AUC compared with NT-proBNP (0.68) for all-cause mortality (P = 0.08). A combination of CYFRA 21-1 and NT-proBNP (AUC = 0.71) improved the predictive value of the model for all-cause mortality (P = 0.0002 compared with NT-proBNP).

CONCLUSIONS

Several established tumour biomarkers showed independent associations with indices of severity of HF and independent prognostic value for HF outcomes. This demonstrates that pathophysiological pathways sensed by these tumour biomarkers are also dysregulated in HF.

Mass Spectrometric Imaging of Ceramide Biomarkers Tracks Therapeutic Response in Traumatic Brain Injury

Traumatic brain injury (TBI) is a serious public health problem and the leading cause of death in children and young adults. It also contributes to a substantial number of cases of permanent disability. As lipids make up over 50% of the brain mass and play a key role in both membrane structure and cell signaling, their profile is of particular interest. In this study, we show that advanced mass spectrometry imaging (MSI) has sufficient technical accuracy and reproducibility to demonstrate the anatomical distribution of 50 μm diameter microdomains that show changes in brain ceramide levels in a rat model of controlled cortical impact (CCI) 3 days post injury with and without treatment. Adult male Sprague-Dawley rats received one strike and were euthanized 3 days post trauma. Brain MS images showed increase in ceramides in CCI animals compared to control as well as significant reduction in ceramides in CCI treated animals, demonstrating therapeutic effect of a peptide agonist. The data also suggests the presence of diffuse changes outside of the injured area. These results shed light on the extent of biochemical and structural changes in the brain after traumatic brain injury and could help to evaluate the efficacy of treatments.

Mass spectrometry imaging of rat brain lipid profile changes over time following traumatic brain injury

BACKGROUND

Mild traumatic brain injury (TBI) is a common public health issue that may contribute to chronic degenerative disorders. Membrane lipids play a key role in tissue responses to injury, both as cell signals and as components of membrane structure and cell signaling. This study demonstrates the ability of high resolution mass spectrometry imaging (MSI) to assess sequences of responses of lipid species in a rat controlled cortical impact model for concussion.

NEW METHOD

A matrix of implanted silver nanoparticles was implanted superficially in brain sections for matrix-assisted laser desorption (MALDI) imaging of 50μm diameter microdomains across unfixed cryostat sections of rat brain. Ion-mobility time-of-flight MS was used to analyze and map changes over time in brain lipid composition in a rats after Controlled Cortical Impact (CCI) TBI.

RESULTS

Brain MS images showed changes in sphingolipids near the CCI site, including increased ceramides and decreased sphingomyelins, accompanied by changes in glycerophospholipids and cholesterol derivatives. The kinetics differed for each lipid class; for example ceramides increased as early as 1 day after the injury whereas other lipids changes occurred between 3 and 7 days post injury.

COMPARISON WITH EXISTING METHOD(S)

Silver nanoparticles MALDI matrix is a sensitive new tool for revealing previously undetectable cellular injury response and remodeling in neural, glial and vascular structure of the brain.

CONCLUSIONS

Lipid biochemical and structural changes after TBI could help highlighting molecules that can be used to determine the severity of such injuries as well as to evaluate the efficacy of potential treatments.

Differential innate responses of chickens and ducks to low-pathogenic avian influenza

Ducks and chickens are hosts of avian influenza virus, each with distinctive responses to infection. To understand these differences, we characterized the innate immune response to low-pathogenicity avian influenza virus H7N1 infection in chickens and ducks. Viral RNA was detected in the lungs of chickens from day 0.8 to 7, in ducks mainly at day 4. In both species, viral RNA was detected in the bursa and gut. Infection in chickens resulted in up-regulation of interferon (IFN)-α and IFN-β mRNA, while in the ducks IFN-γ mRNA was strongly up-regulated in the lung and bursa. In chickens and ducks, all investigated pathogen recognition receptor (PRR) mRNAs were up-regulated; however, in the chicken lung Toll-like receptor (TLR)7 and melanoma differentiation-associated protein (MDA)-5 mRNA were strongly induced. TLR3, TLR7 and MDA-5 responses correlated with IFN-α and IFN-β responses in chickens, but in ducks a correlation between IFN-α and TLR7, retinoic acid-inducible gene-I and MDA-5 was absent. We studied the responses of duck and chicken splenocytes to poly(I:C) and R848 analogues to analyse the regulation of PRRs without the interfering mechanisms of the influenza virus. This revealed IFN-α and IFN-γ responses in both species. MDA-5 was only strongly up-regulated in chicken splenocytes, in which time-related PRR responses correlated with the IFN-α and IFN-β response. This correlation was absent in duck splenocytes. In conclusion, chickens and ducks differ in induction of MDA-5, TLR7 and IFN-α mRNA after an influenza virus infection in vivo and after in vitro stimulation with TLR antagonists.

Differences in highly pathogenic avian influenza viral pathogenesis and associated early inflammatory response in chickens and ducks

We studied the immunological responses in the lung, brain and spleen of ducks and chickens within the first 7 days after infection with H7N1 highly pathogenic avian influenza (HPAI). Infection with HPAI caused significant morbidity and mortality in chickens, while in ducks the infection was asymptomatic. The HPAI viral mRNA load was higher in all investigated tissues of chickens compared with duck tissues. In the lung, brain and spleen of HPAI-infected chickens, a high, but delayed, pro-inflammatory response of IL-6 and IL-1β mRNA was induced, including up-regulation of IFN-β, IFN-γ, TLR3 and MDA-5 mRNA from 1 day post infection (p.i.). Whereas in ducks already at 8 h p.i., a quicker but lower response was found for IL-6, IL-1β and iNOS mRNA followed by a delayed activation of TLR7, RIG-I, MDA5 and IFN-γ mRNA response. Virus-infected areas in the lung of chickens co-localized with KUL-01⁺ (macrophages, dendritic cells), CD4⁺, and CD8α⁺ cells, during the first day after infection. However, only KUL-01⁺ cells co-localized with the virus after 1 day p.i. In ducks, CVI-ChNL-68.1⁺ (macrophage-like cells), CD4⁺ and CD8α⁺ cells and apoptosis co-localized with the virus within 8 h p.i. Apoptosis was detected in the brain and lung of HPAI-infected chickens after 2 days p.i. and apoptotic cells co-localized with virus-infected areas. In conclusion, excessive delayed cytokine inflammatory responses but inadequate cellular immune responses may contribute to pathogenesis in chickens, while ducks initiate a fast lower cytokine response followed by the activation of major pattern recognition receptors (TLR7, RIG-I, MDA5) and a persistent cellular response.

Gangliosides and ceramides change in a mouse model of blast induced traumatic brain injury

Explosive detonations generate atmospheric pressure changes that produce nonpenetrating blast induced "mild" traumatic brain injury (bTBI). The structural basis for mild bTBI has been extremely controversial. The present study applies matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging to track the distribution of gangliosides in mouse brain tissue that were exposed to very low level of explosive detonations (2.5-5.5 psi peak overpressure). We observed major increases of the ganglioside GM2 in the hippocampus, thalamus, and hypothalamus after a single blast exposure. Moreover, these changes were accompanied by depletion of ceramides. No neurological or brain structural signs of injury could be inferred using standard light microscopic techniques. The first source of variability is generated by the Latency between blast and tissue sampling (peak intensity of the blast wave). These findings suggest that subtle molecular changes in intracellular membranes and plasmalemma compartments may be biomarkers for biological responses to mild bTBI. This is also the first report of a GM2 increase in the brains of mature mice from a nongenetic etiology.

Analysis of native biological surfaces using a 100 kV massive gold cluster source

In the present work, the advantages of a new, 100 kV platform equipped with a massive gold cluster source for the analysis of native biological surfaces are shown. Inspection of the molecular ion emission as a function of projectile size demonstrates a secondary ion yield increase of ~100× for 520 keV Au(400)(4+) as compared to 130 keV Au(3)(1+) and 43 keV C(60). In particular, yields of tens of percent of molecular ions per projectile impact for the most abundant components can be observed with the 520 keV Au(400)(4+) probe. A comparison between 520 keV Au(400)(4+) time-of-flight-secondary ion mass spectrometry (TOF-SIMS) and matrix assisted laser desorption ionization-mass spectrometry (MALDI-MS) data showed a similar pattern and similar relative intensities of lipid components across a rat brain sagittal section. The abundant secondary ion yield of analyte-specific ions makes 520 keV Au(400)(4+) projectiles an attractive probe for submicrometer molecular mapping of native surfaces.

Transient lower oesophageal sphincter relaxation in achalasia: everything but LOS relaxation

In conducting clinical high-resolution oesophageal pressure topography (HROPT) studies we observed that after subjects sat upright between series of supine and upright test swallows, they frequently had a transient lower oesophageal sphincter relaxation (TLOSR). When achalasia patients were studied in the same protocol, they exhibited a similar HROPT event leading to the hypothesis that achalasics had incomplete TLOSRs. We reviewed clinical HROPT studies of 94 consecutive non-achalasics and 25 achalasics. Studies were analyzed for a TLOSR-like event during the study and, when observed, that TLOSR-like event was characterized for the degree and duration of distal oesophageal shortening, the degree of LOS relaxation, associated crural diaphragm (CD) inhibition, oesophageal pressurization and upper oesophageal sphincter (UOS) relaxation. About 64/94 (68%) non-achalasics and 15/24 (63%) of achalasics had a pressure topography event after the posture change characterized by a prolonged period of distal oesophageal shortening and/or LOS relaxation. Events among the non-achalasics and achalasics were similar in terms of magnitude and duration of shortening and all were associated with CD inhibition. Similar proportions had associated non-deglutitive UOS relaxations. The only consistent differences were the absence of associated LOS relaxation and the absence of HROPT evidence of reflux among the achalasics leading us to conclude that their events were incomplete TLOSRs. Achalasic patients exhibit a selective defect in the TLOSR response suggesting preservation of all sensory, central and efferent aspects of the requisite neural substrate with the notable exception of LOS relaxation, a function of inhibitory (nitrergic) myenteric plexus neurons.

Immunological determinants of the outcomes from primary hepatitis C infection

Individuals infected with hepatitis C virus (HCV) have two possible outcomes of infection, clearance or persistent infection, determined by a complex set of virus-host interactions. The focus of this review is the host mechanisms that facilitate clearance. Strong evidence points to characteristics of the cellular immune response as the key determinants of outcome, with evidence for the coordinated effects of the timing, magnitude, and breadth, as well as the intra-hepatic localisation of CD4+ and CD8+ T cell responses being critical. The recent discovery of viral evasion strategies targeting innate immunity suggests that interferon-stimulated gene products are also important. A growing body of evidence has implicated polymorphisms in both innate and adaptive immune response genes as determinants of viral clearance in individuals with acute HCV.

Astaxanthin reduces ischemic brain injury in adult rats

Astaxanthin (ATX) is a dietary carotenoid of crustaceans and fish that contributes to their coloration. Dietary ATX is important for development and survival of salmonids and crustaceans and has been shown to reduce cardiac ischemic injury in rodents. The purpose of this study was to examine whether ATX can protect against ischemic injury in the mammalian brain. Adult rats were injected intracerebroventricularly with ATX or vehicle prior to a 60-min middle cerebral artery occlusion (MCAo). ATX was present in the infarction area at 70-75 min after onset of MCAo. Treatment with ATX, compared to vehicle, increased locomotor activity in stroke rats and reduced cerebral infarction at 2 d after MCAo. To evaluate the protective mechanisms of ATX against stroke, brain tissues were assayed for free radical damage, apoptosis, and excitoxicity. ATX antagonized ischemia-mediated loss of aconitase activity and reduced glutamate release, lipid peroxidation, translocation of cytochrome c, and TUNEL labeling in the ischemic cortex. ATX did not alter physiological parameters, such as body temperature, brain temperature, cerebral blood flow, blood gases, blood pressure, and pH. Collectively, our data suggest that ATX can reduce ischemia-related injury in brain tissue through the inhibition of oxidative stress, reduction of glutamate release, and antiapoptosis. ATX may be clinically useful for patients vulnerable or prone to ischemic events.

A Minimalist Approach to MALDI Imaging of Glycerophospholipids and Sphingolipids in Rat Brain Sections

Matrix assisted laser desorption/ionization mass spectrometry (MALDI-MS) is a powerful tool that has allowed researchers to directly probe tissue molecular structure and drug content with minimal manipulations, while maintaining anatomical integrity. In the present work glycerophospholipids and sphingolipids images were acquired from 16 µm thick coronal rat brain sections using MALDI-MS. Images of phosphatidylinositol 38:4 (PI 38:4), suifatide 24:1 (ST 24:1), and hydroxyl sulfatide 24:1 (ST 24:1 (OH)) were acquired in negative ion mode, while the images of phosphatidylcholine 34:1 (PC 34:1), potassiated phosphatidylcholines 32:0 (PC32:0 + K(+)) and 36:1 (PC 36:1 +K(+)) were acquired in positive ion mode. The images of PI 38:4 and PC 36:1+K(+) show the preferential distribution of these two lipids in gray matter; and the images of two sulfatides and PC 32:0+K(+) show their preferential distribution in white matter. In addition, the gray cortical band and its adjacent anatomical structures were also identified by contrasting their lipid makeup. The resulting images were compared to lipid images acquired by secondary ion mass spectrometry (SIMS). The suitability of TLC sprayers, Collison Nebulizer, and artistic airbrush were also evaluated as means for matrix deposition.

A study of phospholipids by ion mobility TOFMS

Combining matrix-assisted laser desorption/ionization (MALDI) mass spectrometry with ion mobility (IM) results in the fast sorting of biomolecules in complex mixtures along trend lines. In this two-dimensional (2D) analysis of biological families, lipids, peptides, and nucleotides are separated from each other by differences in their ion mobility drift times in a timescale of hundreds of microseconds. Molecular ions of similar chemical type fall along trend lines when plotted in 2D plots of ion mobility drift time as a function of m/z. In this study, MALDI-IM MS is used to analyze species from all of the major phospholipid classes. Complex samples, including tissue extracts and sections, were probed to demonstrate the effects that radyl chain length, degree of unsaturation, and class/head group have upon an ion's cross section in the gas phase. We illustrate how these changes can be used to identify individual lipid species in complex mixtures, as well as the effects of cationization on ion cross section and ionization efficiency.

Engaging recreational fishers in management and conservation: global case studies

Globally, the number of recreational fishers is sizeable and increasing in many countries. Associated with this trend is the potential for negative impacts on fish stocks through exploitation or management measures such as stocking and introduction of non-native fishes. Nevertheless, recreational fishers can be instrumental in successful fisheries conservation through active involvement in, or initiation of, conservation projects to reduce both direct and external stressors contributing to fishery declines. Understanding fishers' concerns for sustained access to the resource and developing methods for their meaningful participation can have positive impacts on conservation efforts. We examined a suite of case studies that demonstrate successful involvement of recreational fishers in conservation and management activities that span developed and developing countries, temperate and tropical regions, marine and freshwater systems, and open- and closed-access fisheries. To illustrate potential benefits and challenges of involving recreational fishers in fisheries management and conservation, we examined the socioeconomic and ecological contexts of each case study. We devised a conceptual framework for the engagement of recreational fishers that targets particular types of involvement (enforcement, advocacy, conservation, management design [type and location], research, and monitoring) on the basis of degree of stakeholder stewardship, scale of the fishery, and source of impacts (internal or external). These activities can be enhanced by incorporating local knowledge and traditions, taking advantage of leadership and regional networks, and creating collaborations among various stakeholder groups, scientists, and agencies to maximize the probability of recreational fisher involvement and project success.

Cytokine expression profiles of patients with acute myelogenous leukemia (AML) and non-Hodgkin lymphoma (NHL) detected by multiplex assay

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Background: To determine the cytokine expression profiles of patients with AML and NHL using a sensitive bead-based Luminex multiplex assay in a routine clinical diagnostic setting. Methods: Blood (plasma/serum) samples were collected from ten AML and five NHL patients. Six control samples from patients diagnosed as non-neoplastic/non-autoimmune/non-inflammatory were also analyzed for comparison. All samples were frozen prior to analysis. Using a bead-based Luminex assay (Human Cytokine 8-Plex Assay, Bio- Rad, Hercules, CA) we analyzed these samples for a panel of cytokines (IL-2, IL-4, IL-6, IL-10, GM-CSF, IFN-gamma, and TNF-alpha). This assay uses polystyrene microspheres, which provides simultaneous quantitation of these cytokines in a single sample. The expression levels were presented in picograms/mL. Average values for each of these markers were obtained for each group of patients (AML versus NHL versus Controls), and their expression levels were compared using χ2 analysis. Results: Overall, there was a significant difference in the expression profiles of all these cytokines among three patients groups (χ2, P < 0.001). All cytokines were consistently expressed at low levels in NHL patients as compared to control group. However, the levels of IL-6 and IL-8 were increased by 2.7 and 5.8 times, respectively in AML patients as compared to controls. Conclusions: The low levels of cytokines in NHL and AML patients suggest suppressed immune system in these two disease conditions; however, these findings warrant further studies to explore the underlying mechanisms for the increased levels of IL-6 and IL-8 in AML patients. Currently, studies are in progress to compare the levels of cytokines measured by Luminiex assay in different stages of leukemias and lymphomas (initial, post treatment and recovery phase etc.). These studies are partially funded by grants from the National Institute of Health/National Cancer Institute (RO1-CA98932–01 and U24-CA086359).

No significant financial relationships to disclose.

Immune responses in Eimeria acervulina infected one-day-old broilers compared to amount of Eimeria in the duodenum, measured by real-time PCR

T-cell responses are supposed to be the major immune reactions in broilers infected with Eimeria. The nature of such T-cell responses is influenced by the species of Eimeria involved, age of the host, amount of parasites and the preceding infection history. In young chicks the intestine is still developing in length while the lymphocyte populations in the gut develop and differentiate. In chicks infected at young age the immune response may be different in quality as compared to responses in adults. We investigated the (T-cell) immune responses of young broilers to a primary Eimeria acervulina infection in relation to the number of parasites used for infection. In our experiment we infected one-day-old broilers with a low (5 x 10(2) oocysts) and a high (5 x 10(4) oocysts) dose of E. acervulina. We used a newly developed species specific real-time PCR to quantify total amount of parasites in the duodenum as the number of oocysts in faeces may not be representative for the exposure of the gut immune system. We characterized T-cell subsets in the duodenum by means of FACS-analyses, lymphocyte proliferation assays with spleen lymphocytes and the mRNA profiles of different cytokines (TGF-beta2, -4, IFN-gamma, IL-2, -6, -8 and -18) in the duodenum by means of real-time PCR. From day 5 p.i. broilers with a high dose of E. acervulina had a significantly lower body weight than the control group. No increase in CD4(+) cells, but a strong increase in CD8(+) cells was observed at days 7 and 9 p.i. in the duodenum of broilers infected with a high dose E. acervulina. IL-8 mRNA responses were observed after infection with low and with high infection doses, but no IFN-gamma and TGF-beta mRNA responses were found in the duodenum. The specific proliferative T-cell responses to a low infectious dose were not significantly different as compared to the control group. In conclusion, based on the kinetics of observed responses a primary infection with a high dose of E. acervulina in one-day-old broilers seems to generate an immune response that shows a peak at the time of oocyst excretion, whereas the immune response to a low dose is less explicit.

Molecular basis for the specificity of p27 toward cyclin-dependent kinases that regulate cell division

The cyclin-dependent kinase inhibitors (CKIs) bind to and directly regulate the catalytic activity of cyclin-dependent kinase (Cdk)/cyclin complexes involved in cell cycle control and do not regulate other, closely related Cdks. We showed previously that the CKI, p27, binds to Cdk2/cyclin A though a sequential mechanism that involves folding-on-binding. The first step in the kinetic mechanism is interaction of a small, highly dynamic domain of p27 (domain 1) with the cyclin subunit of the Cdk2/cyclin A complex, followed by much slower binding of a more lengthy and less flexible domain (domain 2) to Cdk2. The second step requires folding of domain 2 into the kinase inhibitory conformation. Rapid binding of p27 domain 1 to cyclin A tethers the inhibitor to the binary Cdk2/cyclin A complex, which reduces the entropic barrier associated with slow binding of domain 2 to the catalytic subunit. We show here that p27/cyclin interactions are an important determinant of p27 specificity towards cell cycle Cdks. We used surface plasmon resonance, limited proteolysis, mass spectrometry, and NMR spectroscopy to study the interaction of p27 with Cdk2/cyclin A, and with another Cdk complex, Cdk5/p25, that is involved in neurodegeneration. Importantly, Cdk5/p35 (the parent complex of Cdk5/p25) is not regulated by p27 in neurons. Our results show that p27 binds to Cdk5 and Cdk2 with similar, slow kinetics. However, p27 fails to interact with p25 within the Cdk5/p25 complex, which we believe prevents formation of a kinetically trapped, inhibited p27/Cdk5/p25 complex in vivo. The helical topology of p25 is very similar to that of cyclin A. However, p25 lacks the MRAIL sequence in one helix that, in the cell cycle cyclins, mediates specific interactions with domain 1 of p21 and p27. Our results strongly suggest that p21 and p27, related Cdk inhibitors, select their cell cycle regulatory Cdk targets by binding specifically to the cyclin subunit of these Cdk/cyclin complexes as a first step in a sequential, folding-on-binding mechanism.

Vitamin and trace mineral content in feed of breeders and their progeny: effects of growth, feed conversion and severity of malabsorption syndrome of broilers

1. A study was conducted to investigate the effects of several vitamins and trace elements chickens and in chickens experimentally infected with malabsorption syndrome (MAS). 2. Vitamins and trace minerals in feed were varied. Breeders received either a basal amount of vitamins and trace minerals (low mix) or an increased amount (high mix). Their progeny also received either a low mix or a high mix. Effects of different breeder and broiler mix combinations on broiler performance, heamatology, spleen weight and humoral response were examined in control chickens. The effects of the different feeds and breeder, broiler combinations at the severity and recovery of MAS infection were also studied. 3. In general, the immune system can be stimulated by addition of vitamins and trace minerals, without affecting the growth potential of the controls. The number of leukocytes increased on d 1 in the broilers descended from breeders receiving high mix. The response to Newcastle disease virus boost was affected by the different amount of vitamins. 4. When breeders received a high mix the number of infiltrating polymorphonuclear leukocytes in the intestine was higher compared with breeders receiving basal amounts of minerals and vitamins. Also the recovery rate of intestinal lesions, cystic crypts of Lieberkühn and villus atrophy, as observed by histopathology, was faster in the groups where the breeders received high mix.

Physiological effects of elevated plasma corticosterone concentrations in broiler chickens. An alternative means by which to assess the physiological effects of stress

Research on physical or psychological stress, in order to monitor objective parameters for animal welfare, is usually performed during experimental stress induction. To avoid treatment of animals with physical or physiological stress, addition of the stress-related hormone corticosterone to the drinking water, may serve as a practical alternative to reproducibly investigate hormone-related stress in broiler chickens. Rapid uptake of the hormone and distribution in the bloodstream were affirmed by elevated plasma corticosterone concentrations immediately after start of the treatment. The effect of hormone administration was evaluated by examination of corticosterone-sensitive organs. Comparable to the observations during physiological stress, we found in our model that uptake of endogenous corticosterone reduced body and spleen growth, increased heterophil counts, and decreased formation of antibodies against sheep red blood cells. Furthermore, corticosterone decreased adrenal gland responsiveness, measured by corticosterone production, after a challenge with adrenocorticotropic hormone. The simple performance, and the close relation between circulating corticosterone levels and heterophil counts, makes this an easy and quick method that is sensitive to increased levels of circulating corticosterone from base levels. The changed responsiveness of the adrenal glands to adrenocorticotropic hormone after increased circulating corticosterone levels may be an indication of the coping strategies during stress. Therefore, this test may be a promising tool in the research of adaptation to stress by broiler chickens.

Automated blood cell count: a sensitive and reliable method to study corticosterone-related stress in broilers

In chickens the heterophil/lymphocyte ratio (H/L) has proved to be a valuable tool in stress related research. In general, H/L is determined with the microscopic differential count on a blood film. We evaluated automated analysis for measuring blood cell parameters in relation to corticosterone in a recently introduced corticosterone model. Discrepancies between microscopic and automated counts were found for the percentage of monocytes and basophils. The relative H/L ratio appeared to be sensitive for increased plasma corticosterone levels. However, the increase in heterophil frequencies measured with the hematology analyzer proved to be the most sensitive method for the measurement of changes in plasma corticosterone concentrations. We therefore propose automated hematological analysis as a simple and sensitive tool to study the effects of physiological corticosterone concentrations on blood cell parameters in relation to stress in broiler chickens.

Development of organs and intestinal mucosa leukocytes in four broiler lines that differ in susceptibility to malabsorption syndrome

Growth retardation in young broiler chicks due to poor nutrient metabolism, commonly known as malabsorption syndrome (MAS), is a widespread problem caused by enteric infections with a combination of pathogens mainly viruses. Genetic lines of broiler chickens differ in susceptibility to the syndrome. A difference in growth retardation was observed among four broiler lines (BL) after oral inoculation at 1 d of age with intestinal homogenates obtained from MAS-affected birds. Two of the lines that are more susceptible to MAS had severe weight gain depression. To uncover the factors that play a role in the susceptibility to MAS, we analyzed the growth rate of the body and vital organs and the quantity of leukocytes in the peripheral blood and intestinal mucosa. The development of the intestine, liver, bursa of Fabricius, and spleen was similar among the BL. The resistant BL had higher numbers of peripheral blood leukocytes, especially lymphocytes, at 1 d of age. A significant difference was noted in the numbers of CD4+ T cells and CD8+ T cells in the intestinal villi. At the ages of 3 and 8 d, the susceptible BL had more CD8+ T cells in the villi, whereas the ratios of CD4+:CD8+ T cells were higher in the resistant BL. This difference in the number of T-cell subpopulations in the intestinal mucosa might be an important factor in the difference in susceptibility to the enteric infections associated with MAS.

Effect of an in ovo infection with a Dutch avian leukosis virus subgroup J isolate on the growth and immunological performance of SPF broiler chickens

The effect of an in ovo infection with a Dutch isolate of avian leukosis virus subgroup J (ALV-J) on the growth of specific pathogen free (SPF) broiler chickens was analysed. During this study, possible immune suppressive effects of ALV-J were assessed by measuring delayed-type hypersensitivity with keyhole limpet haemocyanin (KLH), natural killer (NK) cell activity, the production of radicals of nitric oxide (NO) by macrophages, humoral immune response against Newcastle and infectious bursal disease vaccine viruses, and automated total and differential leukocyte counts. In an attempt to elucidate the underlying causal mechanisms of the induced growth retardation, 3,3',5-triiodothyronine (T3) concentrations in serum were measured. Four experiments were conducted. In experiment 1, ALV-J-injected birds were compared with ALV subgroup A (ALV-A)-injected and negative control chickens. In experiment 2, ALV-J-injected birds were only compared with negative controls. Finally, in experiments 3a and 3b, ALV-J-injected chickens were compared with negative controls and a group of chickens in which only 10% of birds had been injected with ALV-J. Birds were injected in ovo at day 7 of incubation with 10(4) median tissue culture infectious dose (TCID(50)) ALV-J or ALV-A, except in experiment 3a where 10(2) TCID(50) ALV-J was injected. Significant growth suppression was found in all 100% of ALV-J-infected groups. The average growth retardation of ALV-J-infected birds compared with negative controls at 6 weeks of age was approximately 8, 11, 2.5 and 6% for the four successive experiments performed. The delayed-type hypersensitivity test against KLH of ALV-J-infected birds showed a tendency towards lower wattle thickness; however, the difference with controls was not significant (P > 0.05). The same was true for NK cell activity and NO production by macrophages, although the difference was not significant. The total and differential leukocyte counts performed on blood samples from birds at 3, 4 and 6 weeks of age as well as the humoral immune response against Newcastle and infectious bursal disease vaccine viruses did not show significant differences between treatment groups either. Only the number of basophils were significantly higher (P = 0.02) in ALV-J-infected birds at 3 weeks of age. No significant lower T(3) levels were found in ALV-J-infected birds in weeks 2 and 3 (experiment 2) and weeks 3 and 5 (experiment 3b); however, at 4 weeks (experiment 2) and 6 weeks (experiment 3b) of age, T(3) levels were significantly lower suggesting mild hypothyroidism in these broilers. In conclusion, the present experiments show the occurrence of significant growth retardation in SPF broilers after an ALV-J in ovo infection. The various studies performed to assess the immune competence of ALV-J-infected chickens did not show significant differences in immune responsiveness. The assays on cellular immunity showed a tendency to a lower response in ALV-J-infected birds, but these differences were not statistically significant.

Teledermatology as a tool for communication between general practitioners and dermatologists

A feasibility study of teledermatology was undertaken in Groningen. Six general practitioners (GPs) sent digital images by email, along with relevant patient information, to dermatologists at the Martini Ziekenhuis Groningen, a general non-academic hospital. The dermatologists returned their responses by email. A total of 89 cases were dealt with in this way. On average, the GPs took three photographs per patient. The time taken by the GP to produce and transmit the images, and to implement the telemedicine advice received from the dermatologist, was 9 min and 3 min, respectively. The time spent on diagnosis, provision of advice and response by email amounted to 10 min for the dermatologist. It was concluded that teleconsultations by email are feasible in the daily practice of GPs and dermatologists in a general non-academic hospital. Generally, GPs, dermatologists and patients were satisfied with teleconsultations. Furthermore, GPs reported that 63% of the teleconsultations were of educational value.

Chronic salicylism resulting in noncardiogenic pulmonary edema requiring hemodialysis

Salicylate intoxication is frequently overlooked as a cause of noncardiogenic pulmonary edema and altered mental status in adult patients. We describe a 42-year-old woman who presented with two episodes of recurrent noncardiogenic pulmonary edema requiring intubation. The first admission to hospital triggered an extensive initial workup that did not indicate a cause for the pulmonary edema. At the second presentation, recognition of the clinical syndrome in the emergency department led to the correct diagnosis of salicylate intoxication. The patient was successfully treated with hemodialysis and urinary alkalinization, leading to rapid resolution of pulmonary edema and extubation. Several aspects of the clinical presentation suggest that the patient suffers from chronic salicylism, probably complicated by episodic superimposed acute intoxication, a condition often misdiagnosed or diagnosed late in the course of disease, contributing to substantial morbidity and mortality in these patients. Maintenance of a high index of suspicion and rapid institution of appropriate therapy including hemodialysis once the diagnosis is established is an important determinant of outcome in this serious but underdiagnosed disorder.

Effects of ZK-807834, a novel inhibitor of factor Xa, on arterial and venous thrombosis in rabbits

Inhibition of factor Xa (FXa) may interrupt thrombus progression. This study compared the antithrombotic activity of a novel FXa inhibitor, ZK-807834 [MW, 527 D; Ki (human FXa), 0.11 nM], with recombinant tick anticoagulant peptide [rTAP; MW, 6,685 D; Ki, (human FXa) = 0.28 nM], and DX-9065a [MW 445 D, Ki (human FXa), 40 nM] in rabbits with arterial thrombosis induced by electrical vascular injury. ZK-807834 also was compared with low molecular weight heparin (LMWH; MW, 5,500 D) during venous thrombosis induced by placing a copper wire and threads in the vena cava. Inhibitors were administered as an i.v. bolus and 2-h infusion. Total dosages of ZK-807834, > or =0.7 micromol/kg (n = 18); rTAP, > or =1 micromol/kg (n = 18); or DX-9065a, > or =11 micromol/kg (n = 18) decreased the incidence of arterial thrombotic occlusion compared with control animals (p < 0.05). However, five of six animals given the lowest effective dosage of rTAP and four of six animals given DX-9065a bled from a surgical incision >5 min, but only two of six animals given ZK-807834 bled >5 min. Venous clot weights were reduced compared with controls for dosages of ZK-807834 > or =0.007 micromol/kg (n = 36) or LMWH > or =0.2 micromol/kg (n = 18). Prothrombin time (PT) and activated partial thromboplastin time (aPTT) were unchanged from baseline at the minimally effective dose of ZK-807834, whereas aPTT was increased twofold at the effective dose of LMWH. Thus ZK-807834 may be useful to attenuate thrombosis at lower dosages and with less perturbation of systemic hemostasis compared with available agents.

Design, synthesis, and in vitro biological activity of benzimidazole based factor Xa inhibitors

Inhibitors based on the benzimidazole scaffold showed subnanomolar potency against Factor Xa with 500-1000-fold selectivity against thrombin and 50-100-fold selectivity against trypsin. The 2-substituent on the benzimidazole ring had a strong impact on the FXa inhibitory activity. Crystallography studies suggest that the 2-substituent may have a conformational effect favoring the extended binding conformation.

The urine/plasma electrolyte ratio: a predictive guide to water restriction

Patients with hypotonic hyponatremia are encountered commonly in the general practice of medicine. Nearly all strategies for the management of subacute or chronic hyponatremia call for some amount of water restriction. The considerations for such a prescription have not been addressed in the literature. We describe therefore a simple approach grounded in the physiology of electrolyte-free water clearance that can be used at the bedside.

Efficacy of an anti-CD138 immunotoxin and doxorubicin on drug-resistant and drug-sensitive myeloma cells

Multidrug resistance is an increasing problem in the treatment of cancer. We evaluated in vitro the effect of an anti-CD138 plasma-cell-specific immunotoxin (IT, B-B4-SO6) in combination with the chemotherapeutic drug doxorubicin on drug-sensitive and drug-resistant variants of the multiple-myeloma (MM)-derived cell line RPMI8226 and freshly isolated malignant-myeloma cells. Drug-resistant RPMI8226 cells were still sensitive to the IT, although to a lesser extent than drug-sensitive cells. In the clonogenic assay, using 10 nM B-B4-SO6, at least 5 logs kill was found for drug-sensitive RPMI8226 cells, vs. 2.5 logs kill for the drug-resistant RPMI8226 cells. When a sub-optimal dose of 1 nM IT was combined with 3 ng/ml doxorubicin, which was toxic for drug-sensitive but not for drug-resistant cells, an additive effect was found for drug-sensitive RPMI8226 cells. The IT did not influence the sensitivity of resistant cells for doxorubicin. We therefore speculate that this type of IT, may be of more value in combination with primary chemotherapy. The effect of B-B4-SO6 on malignant-myeloma cells of patients was investigated in a viability assay. Both drug-sensitive and drug-resistant cells from MM patients were sensitive to B-B4-SO6. After 2 days, a 50% kill of malignant cells was found when 10 nM IT were used. Doxorubicin was effective only on sensitive cells, and there was a tendency for an additive effect in the combination of these cells.

Unusual cluster of mild invasive serogroup C meningococcal infection in a university college

The objective of this study was to describe the epidemiology and public health response to an apparent cluster of Neisseria meningitidis serogroup C infection in university students in a residential college. A conventional epidemiological approach was taken, supported by routine and novel diagnostic techniques. Over the two days of 21-22 August 1997, three cases of suspected meningococcal infection were notified from a residential college complex at a university campus in the Sydney metropolitan area. Neisseria meningitidis was grown from throat swabs of all three cases, and was isolated from the blood of one case only. All three isolates were typed as C:2a:P1.5,2. Seroconversion was demonstrated by a novel method in the three cases. Rifampicin was given to all identified contacts. Forty-seven days after the index case, a 19 year old female living in the same complex was diagnosed with bacterial meningitis, and identified contacts given rifampicin. When this isolate was found to be group C, it was decided to vaccinate residents of the college complex. Genotyping and serotyping (C:2a:P1.5) later revealed the fourth isolate to be distinct from isolates from Cases 1-3. In conclusion the authors note that Australia's increasing capacity to type meningococcal strains is essential to understanding the epidemiology of this disease. Furthermore, typing information is of critical importance when decisions are made regarding mass vaccination. As early antibiotic treatment may inhibit isolation of the organism, development of novel approaches to diagnosis and typing should be supported.

FK506-induced leukoencephalopathy in children with organ transplants

FK506-induced leukoencephalopathy is a well-known entity in adult organ transplant patients. The neurotoxicity of FK506 immunosuppression is frequently reversible, with either reduction or cessation of the drug. This neurologic syndrome is not well documented in children. We report the clinical and radiologic features in four pediatric cases of FK506 leukoencephalopathy. In two of the four patients this syndrome was reversible.

Generation and characterization of mice deficient in hepsin, a hepatic transmembrane serine protease

Hepsin is a type II transmembrane serine protease highly expressed on the surface of hepatocytes. The physiological function of hepsin is not known, although in vitro studies indicate that hepsin plays a role in the initiation of blood coagulation and in hepatocyte growth. To determine the functional importance of hepsin, we generated hepsin-deficient mice by homologous recombination. Homozygous hepsin-/- mice were viable and fertile, and grew normally. In functional assays including tail bleeding time, plasma clotting times, and tissue factor- or LPS-induced disseminated intravascular coagulation models, no significant difference was found between hepsin-/- and wild-type litter mates. Liver weight and serum concentrations of liver-derived proteins or enzymes were similar in hepsin-/- and wild-type mice. Interestingly, serum concentrations of bone-derived alkaline phosphatase were approximately twofold higher in hepsin-/- mice of both sexes when compared with wild-type litter mates. No obvious abnormalities were found in major organs in hepsin-/- mice in histological examinations. Our results indicate that hepsin is not essential for embryonic development and normal hemostasis. Hepsin-/- mice will help to evaluate the long-term effects of hepsin deficiency in these animals.

Metastatic uveal melanoma. A morphologic and immunohistochemical analysis

BACKGROUND

Uveal melanoma often metastasizes late and preferentially to the liver, in contrast to cutaneous melanoma. The objective of the current study was to evaluate the histopathologic and immunohistochemical changes in primary uveal melanomas and their corresponding metastases.

METHODS

The morphology and immunohistochemical reactivity for the melanoma-associated antibodies HMB-45, S-100 protein, and NKI-C3 were assessed for 29 primary uveal melanomas and their corresponding metastatses.

RESULTS

A significant difference in cell type of the primary and the metastatic uveal melanoma was found (P = 0.0001). The metastases derived from the 29 patient's revealed 82.5% epithelioid or nonclassifiable cells. Positive staining of the primary uvea melanomas and their metastases was found to be 93% and 91%, respectively, for HMB-45, 80% and 66%, respectively, for S-100, and 56% and 71%, respectively, for NKI-C3.

CONCLUSIONS

Metastases of uveal melanomas are comprised of a higher grade of malignant cell types. Nonclassifiable cells can be observed in 40% of metastatic lesions. In the current study, HMB-45 proved to be the most sensitive immunohistochemical marker in the analysis of metastatic uveal melanoma and should be used as part of a panel of monoclonal antibodies in the analysis of any metastatic tumor of unknown origin.

A plasmocyte selective monoclonal antibody (B-B4) recognizes syndecan-1

We developed a new monoclonal antibody. B-B4, which specifically identifies human plasma cells. It strongly reacts with all multiple myeloma cell lines and with malignant plasma cells of all tumour samples of the multiple myeloma patients tested. B-B4 does not react with any peripheral blood, bone marrow or tonsil cells. Cloning of the B-B4 antigen reveals that the monoclonal antibody recognizes syndecan-1. It appears that the monoclonal antibody B-B4 is a suitable marker for human plasmocyte identification among haemopoietic cells and a useful probe for the diagnosis of haematological malignancies. Furthermore, this monoclonal antibody can be used for depletions prior to CD34 grafting.