Functional architecture of intracellular oscillations in hippocampal dendrites

Fast electrical signaling in dendrites is central to neural computations that support adaptive behaviors. Conventional techniques lack temporal and spatial resolution and the ability to track underlying membrane potential dynamics present across the complex three-dimensional dendritic arbor in vivo. Here, we perform fast two-photon imaging of dendritic and somatic membrane potential dynamics in single pyramidal cells in the CA1 region of the mouse hippocampus during awake behavior. We study the dynamics of subthreshold membrane potential and suprathreshold dendritic events throughout the dendritic arbor in vivo by combining voltage imaging with simultaneous local field potential recording, post hoc morphological reconstruction, and a spatial navigation task. We systematically quantify the modulation of local event rates by locomotion in distinct dendritic regions and report an advancing gradient of dendritic theta phase along the basal-tuft axis, then describe a predominant hyperpolarization of the dendritic arbor during sharp-wave ripples. Finally, we find spatial tuning of dendritic representations dynamically reorganizes following place field formation. Our data reveal how the organization of electrical signaling in dendrites maps onto the anatomy of the dendritic tree across behavior, oscillatory network, and functional cell states.

Ultrafast Two-Photon Imaging of a High-Gain Voltage Indicator in Awake Behaving Mice

Optical interrogation of voltage in deep brain locations with cellular resolution would be immensely useful for understanding how neuronal circuits process information. Here, we report ASAP3, a genetically encoded voltage indicator with 51% fluorescence modulation by physiological voltages, submillisecond activation kinetics, and full responsivity under two-photon excitation. We also introduce an ultrafast local volume excitation (ULoVE) method for kilohertz-rate two-photon sampling in vivo with increased stability and sensitivity. Combining a soma-targeted ASAP3 variant and ULoVE, we show single-trial tracking of spikes and subthreshold events for minutes in deep locations, with subcellular resolution and with repeated sampling over days. In the visual cortex, we use soma-targeted ASAP3 to illustrate cell-type-dependent subthreshold modulation by locomotion. Thus, ASAP3 and ULoVE enable high-speed optical recording of electrical activity in genetically defined neurons at deep locations during awake behavior.

Management of postoperative pain in maxillofacial surgery

In this review we describe the evidence base for postoperative analgesia after maxillofacial surgery. We discuss the implications of poorly managed pain, risk factors for the development of severe pain, and pharmacological and non-pharmacological analgesic strategies to manage it.

Management of the airway in maxillofacial surgery: part 1

In part 1 of this review of management of the airway in maxillofacial surgery we discuss preoperative assessment of the airway, and the practical means to deal with difficulties. We review the evidence for videolaryngoscopy and flexible indirect laryngoscopy, together with surgical access to the airway including tracheostomy, cricothyroidotomy, and submental intubation.

Fast two-photon imaging of subcellular voltage dynamics in neuronal tissue with genetically encoded indicators

Monitoring voltage dynamics in defined neurons deep in the brain is critical for unraveling the function of neuronal circuits but is challenging due to the limited performance of existing tools. In particular, while genetically encoded voltage indicators have shown promise for optical detection of voltage transients, many indicators exhibit low sensitivity when imaged under two-photon illumination. Previous studies thus fell short of visualizing voltage dynamics in individual neurons in single trials. Here, we report ASAP2s, a novel voltage indicator with improved sensitivity. By imaging ASAP2s using random-access multi-photon microscopy, we demonstrate robust single-trial detection of action potentials in organotypic slice cultures. We also show that ASAP2s enables two-photon imaging of graded potentials in organotypic slice cultures and in Drosophila. These results demonstrate that the combination of ASAP2s and fast two-photon imaging methods enables detection of neural electrical activity with subcellular spatial resolution and millisecond-timescale precision.

DOI:http://dx.doi.org/10.7554/eLife.25690.001

First observation of African tigerfish Hydrocynus vittatus predating on barn swallows Hirundo rustica in flight

A population of African tigerfish Hydrocynus vittatus from the Schroda Dam, actively prey on barn swallows Hirundo rustica in flight. This behaviour was discovered during a radio telemetry study and documented using a motion picture video camera. These results show that an avivorous diet is a part of the feeding biology of H. vittatus, and may occur in other populations.

Deoxynivalenol-induced immunomodulation of human lymphocyte proliferation and cytokine production

Mycotoxins are a structurally diverse group of secondary metabolites produced by different genera of fungi, and include deoxynivalenol (DON), T-2 toxin, aflatoxin B1 (AFB1) and fumonisin B1 (FB1). Despite widespread human exposure and potent immunomodulation in animals, their effects on the human immune system remain to be defined. In this study, the effect of these toxins on human lymphocyte proliferation was evaluated using the MTT assay. Additionally, the effect of DON on cytokine profiles was measured. A 50% inhibition in cell proliferation was observed with a DON concentration of 216 ng/ml. T-2 toxin was more potent with 50% inhibition between 1 and 5 ng/ml. Negligible effects were observed with AFB1 and FB1, and a mixture of DON with either FB1 or AFB1 did not show any synergistic effects in this assay. Short-term treatment of PHA-stimulated lymphocytes with DON (100, 200 and 400 ng/ml) modulated the kinetics of IL-2, IL-4 and IL-6 production. IL-2 levels were up to 12-fold higher (P<0.05) in comparison to control levels at toxin concentrations of 200 and 400 ng/ml 72 h after treatment. IL-4 levels were only slightly elevated and IL-6 levels were slightly inhibited by these DON concentrations. The kinetics of cytokine production was followed for an extended period of 8-9 days at DON concentrations of 200 and 400 ng/ml. At the lower DON concentration (200 ng/ml), IL-2 levels were elevated 17-25-fold with a concomitant mild elevation in IFN-gamma. Consistent with earlier experiments, IL-6 levels were slightly suppressed by DON at this concentration. At 400 ng/ml, IL-2 levels were again significantly (P<0.05) elevated until 6 days post-treatment, while the effects on IL-4 and IL-6 were less marked. These data suggest DON has potent effects on human lymphocyte cytokine production which merit investigation in exposed human populations.

Dose-response effects of methylphenidate on ecologically valid measures of academic performance and classroom behavior in adolescents with ADHD

The effects of methylphenidate on the academic performance and classroom behavior of 45 adolescents with attention deficit hyperactivity disorder were studied. During a 6-week, placebo-controlled medication assessment in the context of a summer treatment program, participants received a double-blind, crossover trial of 3 doses of methylphenidate. Dependent measures included note-taking quality, quiz and worksheet scores, written language usage and productivity, teacher ratings, on-task and disruptive behavior, and homework completion. Group data showed positive effects of methylphenidate on academic measures; however, the greatest benefit came with the lowest dose. Although additional benefit did occur for some participants with higher doses, the largest increment of change usually occurred between the placebo and 10-mg dose. Many adolescents did not experience added benefit with increased dosages, and in some cases they experienced deterioration. Guidelines for assessment of medication effects are discussed.

Television advertising of pharmacy medicines in the United Kingdom

In the UK pharmacy is often promoted as the first port of call for minor ailments and the pharmacist's armamentarium of products is increasing as further products are reclassified from prescription only control. Non-prescription medicines in the UK can be advertised directly to the public but the advertisements must comply with the law. Some medicines, namely pharmacy can only be sold from pharmacies by, or under, the supervision of a pharmacist. This report describes the major findings of a postal survey of community pharmacists on the subject of advertising of pharmacy medicines and put them into context by outlining the legal and quasi-legal requirements. Further other studies concerning the advertising of non-prescription medicines are discussed in the context of requests for, and sales of, medicines available without a prescription.

Effective school-based mental health interventions: advancing the social skills training paradigm

Psychotherapeutic interventions with children have not been as successful in practice as laboratory studies suggest. Two weaknesses frequently cited include the failure of treatment gains to generalize to other times and settings and the lack of individualization. Although social skills interventions have inherent appeal and appear appropriate to address many of the social and emotional problems encountered by children and youth, they have not demonstrated effectiveness despite their widespread use. This article outlines four steps to improve social skills interventions that take advantage of the unique environments of schools and increase the likelihood that social skills interventions can achieve individualization and generalization.

Changes in sensitivity of a human myeloid cell line (U937) to metal toxicity after glutathione depletion

Glutathione (GSH) concentrations have been determined in the human myeloid cell line U937. The effects of modulating GSH concentration on sensitivity to metal toxicity has also been examined. Intracellular concentrations of GSH increased as the cells entered into the cell cycle, reaching a maximum level after 24 hours of cell culture, after which levels declined. Cell concentration was also observed to influence intracellular GSH concentrations. A reciprocal relationship was observed with higher maximum intracellular GSH concentrations being measured in cultures initiated with smaller cell number. The relative toxicity's determined for five metal chlorides were mercury > cadmium > cobalt > zinc > gold. Treatment of cells with N-acetylcysteine (NAC) increased intracellular GSH but had little effect on the absolute or relative toxicity's of the metals. Treatment of cells with L-buthionine-(S-R)-sulfoximine (BSO) depleted intracellular GSH and resulted in increased sensitivity of the cells to gold, 40 fold, cadmium 8 fold and mercury 3 fold.

Mental health services in schools: utilization, effectiveness, and consent

The integration of education and behavioral health services in schools continues to evolve at a rapid pace. Proponents argue that school-based behavioral health programs have many benefits, including greater access to care and improved effectiveness as compared to clinic- or hospital-based services. While preliminary research is encouraging, in general the claims of school behavioral health are not supported by data. Some critics focus on negative aspects of school behavioral health. They claim that behavioral health is being forced upon students and can cite many examples of counseling and treatment administered to children without parental consent. Utilization, effectiveness, and consent are three topics that deserve a great deal of attention in this emerging field, and are the focus of this review.

Aurintricarboxylic acid inhibits apoptosis and supports proliferation in a haemopoietic growth-factor dependent myeloid cell line

The actions of the nuclease inhibitor aurintricarboxylic acid (ATA) were investigated in the growth-factor dependent murine myeloid cell line NSF-60. NSF-60 cells proliferate in response to interleukin-3 (IL-3) and undergo apoptosis when deprived of exogenous IL-3, as demonstrated by the appearance of characteristic DNA 'ladders' following agarose gel electrophoresis. ATA, at concentrations between 5 and 25 microM, inhibited apoptosis in growth-factor deprived cells as demonstrated by inhibition of DNA fragmentation and increased cell survival. ATA at a concentration of 25 microM supported proliferation of the cell line in the absence of exogenous growth-factor. Both ATA and IL-3 increased protein phosphorylation in this cell line. ATA and IL-3 induced proliferation was inhibited by the kinase inhibitors genistein, staurosporine and H-7. These findings suggest that, in NSF-60, ATA is not acting exclusively as an endonuclease inhibitor and that protein phosphorylation is involved in the mechanism of action of ATA in this cell line.

Ontogeny of humoral immunity in northern elephant seal (Mirounga angustirostris) neonates

Northern elephant seal (NES) serum concentrations of total immunoglobulin (Ig) G, an IgG sub-class, and an IgM-like protein were determined by capture immunoassay using three monoclonal antibodies with specificities for Ig of members of the Phocidae pinniped family. These assays were calibrated for use with NES sera using affinity column purified Ig. Concentrations of these Ig populations were estimated in adult female sera sampled at two time points during the lactation period, as well as sera from their pups collected during the first 5 weeks after birth. In pups, concentrations of the IgM-like protein was found to increase rapidly post-partum. In some individuals, values reached mean concentrations within 10-14 days. In addition, rapid increases in pup total IgG and IgG sub-class concentrations were also observed. Collectively, these findings suggest that the majority of post-partum increases in serum Ig can be accounted for by de-novo synthesis.

Presence of a parasitic nematode (Eustrongylidies sp.) in brown trout (Salmo trutta) from a heavy metal contaminated aquatic ecosystem

The Flåt Nickel mine at Evje in southern Norway was mined intensively between 1914 and 1945 with little regard for any potential environmental effect. Much of the ore extracted was smelted at a site adjacent to the river Otra south of Evje. Recent studies have revealed heavy metal pollution in the land surrounding the smelter and in water draining from the mine, leading to concern for the aquatic ecosystem in the river Otra. Brown trout were sampled from an uncontaminated lake nine kilometres upstream from the smelter, from the base of the Oddebekken (a tributary draining the mine water into the Otra), from sites immediately upstream and down stream of the smelter and from a site four kilometres down stream from the smelter. Fish from sites adjacent to the smelter and the base of the Oddebekken were smaller than those from the lake and down stream site. Fish from sites adjacent to the smelter and the base of the Oddebekken were more likely to be infected with parasitic nematode Eustrongylidies. At the population but not the individual level the presence of encapsulated parasitic larvae correlated with the concentrations of two metals, Ni and Cu, in fish.

Nickel, cobalt, zinc and copper levels in brown trout (Salmo trutta) from the river Otra, southern Norway

The Flåt Nickel mine at Evje in southern Norway was mined extensively from 1914 to 1945 with little regard for any potential environmental effect. Much of the ore extracted was smelted at a site adjacent to the river Otra south of Evje. Recent studies have revealed heavy metal pollution in the land surrounding the smelter and in water draining from the mine leading to concern for the aquatic ecosystem in the river Otra. Brown trout were sampled from an uncontaminated lake 9 km upstream from the smelter, from the base of the Oddebekken (a tributary draining the mine water into the Otra), from sites immediately upstream and down stream of the smelter and from a site 4 km down stream from the smelter. Fish from sites adjacent to the smelter and the base of the Oddebekken were smaller than those from the lake and down stream site. Concentrations of the metals were highest in fish sampled where the mine water entered the Otra and gradually decreased in fish further down the river. Fish from the uncontaminated lake had the lowest level of metals.

Incidence and predictors of axillary metastasis in T1 carcinoma of the breast

BACKGROUND

The relatively low incidence (6 to 31 percent) of axillary metastasis in patients with T1 carcinoma of the breast (20 mm or smaller) has led some surgeons to question routine axillary lymphadenectomy (ALND) for patients with no palpable axillary metastases and T1 tumors. This study was undertaken to determine the incidence and predictors of axillary lymph node metastasis in patients with T1 carcinoma of the breast and evaluate the role of sentinel lymphadenectomy (SLND) in this context.

STUDY DESIGN

All patients with T1 invasive carcinoma of the breast treated at the John Wayne Cancer Institute between January 1988 and June 1994 were prospectively studied. The study population was comprised of 259 women who had ALND. Of these patients, 114 were part of a pilot study examining the efficacy of SLND.

RESULTS

Of the 259 women, 69 (27 percent) had axillary metastasis. Hematoxylin and eosin staining identified nodal involvement in 13 percent of patients with T1a and T1b tumors (10 mm or less) and in 30 percent of patients with T1c tumors (p = 0.002). Other factors such as age, hormone receptor status, presence of ductal carcinoma in situ, histology, ploidy, and S-phase were not significant predictors of involvement. A sentinel node was identified in 73 patients: this node accurately predicted axillary status in 72 patients, was the only positive node in nine of 16 patients with axillary involvement, and was 100 percent predictive of axillary status when the primary tumor was 10 mm or less. Retrospective immunohistochemical staining revealed an additional seven patients with positive sentinel nodes. With this technique, even T1a lesions had a 15 percent incidence of axillary metastasis.

CONCLUSIONS

Tumor size is the only accurate predictor of axillary metastasis in patients with T1 carcinoma of the breast. The significant incidence of axillary involvement from T1 tumors mandates accurate staging, even when the tumor is 10 mm or less in size. Examination of a sentinel lymph node may accurately predict axillary metastasis.

Leucocyte interleukin-1-like activity in the common seal (Phoca vitulina) and grey seal (Halichoerus grypus)

Interleukin-1 (IL-1) is an important cytokine with predominantly proinflammatory activities, which have been characterized in many mammals. This study showed the production of IL-1-like bioactivity by cultured seal leucocytes. Increasing concentrations of lipopolysaccharide (LPS) (0-1 micrograms/ml) stimulated an increase in measurable IL-1-like activity in cell culture supernates. This activity increased for the first 24 h after LPS stimulation and the substance responsible had an apparent molecular weight of 17 kDa on gel filtration, similar to that described for other species. Specificity of the bioassay used was confirmed by blocking the bioactivity with an IL-1 receptor antagonist (IL-1 ra).

Improved axillary staging of breast cancer with sentinel lymphadenectomy

OBJECTIVE

The authors evaluated the effect of intraoperative lymphatic mapping and sentinel lymphadenectomy (SLND) on the axillary staging of patients with carcinoma of the breast.

SUMMARY BACKGROUND DATA

The accurate staging of patients with breast cancer is essential to guide management and determine prognosis. The authors previously reported the feasibility and accuracy of SLND in breast carcinoma. Sentinel lymphadenectomy identifies the first ("sentinel") axillary lymph node draining the site of a primary tumor; because this node is the most likely site of axillary metastasis, histopathologic examination of the sentinel node correlates well with examination of the entire axillary contents. The current study compares SLND with standard axillary lymphadenectomy (ALND) for the staging of breast carcinoma.

METHODS

The incidence of axillary node metastasis and micrometastasis in SLND and ALND specimens from patients undergoing operative treatment of a primary breast carcinoma was compared prospectively. Multiple sections of each sentinel lymph node in SLND specimens were examined by hematoxylin and eosin (H&E) staining and by immunohistochemical techniques using antibodies to cytokeratin. One or two sections of each nonsentinel lymph node in ALND specimens were examined by routine H&E staining.

RESULTS

One hundred thirty-four patients underwent ALND (ALND group), and 162 underwent successful SLND followed by completion ALND (SLND group). Both groups were similar with respect to age (median, 55 and 54 years, respectively), palpable primary tumors (54.5% and 59.3%, respectively), palpable axillary nodes (5.2% and 7.4%, respectively), size of primary tumor (median, 1.5 cm in each group), and total number of axillary lymph nodes examined (median, 19 and 21, respectively). The number of patients with axillary metastasis was 39 (29.1%) in the ALND group and 68 (42.0%) in the SLND group (p < 0.03). Of these, 4 of 39 (10.3%) ALND patients (3.0% of all ALND patients) and 26 of 68 (38.2%) SLND patients (16.0% of all SLND patients) had micrometastasis (< or = 2 mm), a highly significant difference (p < 0.0005)

CONCLUSIONS

Sentinel lymphadenectomy with multiple sectioning and immunohistochemical staining of sentinel nodes increases the accuracy of axillary staging in breast cancer and can identify significantly more patients with lymph nodes metastases, especially micrometastases, than can ALND with routine histopathologic processing of lymph nodes.

Identification, characterisation, and measurement of immunoglobulin concentrations in grey (Haliocherus grypus) and common (Phoca vitulina) seals

Concentrations of macroglobulin, total gammaglobulin, and a gammaglobulin subclass were measured in grey and common seals. In pups, immunoglobulin M (IgM) was found to rise rapidly, concentrations reaching adult values by approximately 14 days postpartum. Total IgG concentrations increased more slowly, only approaching 50% of juvenile and adult male values by 30 days after birth. Concentrations of the IgG subclass did not change significantly postpartum. Total IgG concentrations measured in adult female grey seals sampled during lactation were found to be lower than in males and juveniles. This apparent immunosuppression may be associated with pregnancy.

Serum interleukin-8 in inflammatory bowel disease

To investigate the relationship between serum concentrations of interleukin-8 (IL-8) and disease activity in inflammatory bowel disease, serum IL-8 concentrations were measured by enzyme-linked immunosorbent assay (ELISA) in 93 patients. Interleukin-8 levels were compared with plasma interleukin-6 (IL-6) levels in 80 of these patients. Interleukin-8 levels were also measured in ten patients with active Crohn's disease, before and after treatment with a defined formula polymeric diet. Of these patients, 70 out of 93 IL-8 concentrations were below the detection limit of the assay. Levels were higher in patients with active ulcerative colitis (median < 20 pg/mL, 75th centile value = 190) compared with inactive disease (median and 75th centile value < 20; P < 0.05). Interleukin-8 concentrations correlated with a combined score for disease severity and extent (P = 0.01). Thirty-eight per cent (8/20) of patients with active Crohn's disease also had high levels of IL-8 but there was no significant difference between active and inactive disease. There was no correlation between serum IL-8 and plasma IL-6; on the contrary, very few patients had raised blood levels of both cytokines. In the diet treated group, serum IL-8 fell significantly after treatment (median = 37 pg/mL, range < 20-4615 before treatment, median < 20, range < 20-104 after treatment; P = 0.03). The results suggest that although IL-8 may be involved in the inflammatory process in inflammatory bowel disease, it is a poor marker of disease activity.

Identification and partial characterization of common seal (Phoca vitulina) and grey seal (Haliochoerus grypus) interleukin-6-like activities

Interleukin-6 (IL-6) is a pleiotropic molecule with many important immune modulatory actions. We have investigated the production of biological activity of this cytokine in two species of European seal. IL-6-like activity was detected in supernatants from cultured peripheral blood leucocytes. This IL-6-like activity had an apparent molecular weight of 17-26 kDa, similar to that of human IL-6. IL-6-like activity was also detected in plasma taken from seals with symptoms of systemic infection, but not from apparently healthy seals. Inhibition of this plasma and leucocyte derived activity was accomplished with both rabbit and goat antisera raised against recombinant human IL-6. Further investigation using polymyxin-B showed that this activity was not due to residue LPS present in the supernatants or infected plasmas.

Interleukin 6 signal transduction in a human hepatoma cell line (Hep G2)

Interleukin 6 is an important peptide regulatory factor with diverse biological activities including stimulation of acute phase protein synthesis. In this report we describe the effect of signal transduction pathway modulators on interleukin 6 mediated acute phase protein synthesis in a human hepatoma cell line Hep G2. Genistein, a tyrosine kinase inhibitor inhibited the interleukin 6 stimulated synthesis of acute phase proteins suggesting that a tyrosine kinase event participates in the signal transduction pathway. There was no evidence to suggest that protein kinase C had a stimulatory role although this or a related kinase may be involved in down-regulating the interleukin 6 signal.

The use of monoclonal antibodies specific for seal immunoglobulins in an enzyme-linked immunosorbent assay to detect canine distemper virus-specific immunoglobulin in seal plasma samples

A method is described for the measurement of antigen-specific immunoglobulin in seal pup plasmas. Four monoclonal antibodies (H1a, H13a, H24b and H49a) raised against grey seal (Halichoerus grypus) immunoglobulin were used in an ELISA procedure. Levels of canine distemper virus (CDV) specific macroglobulin (IgM like protein) were found to peak approximately 10 days after the first vaccination. Levels of other smaller CDV-specific immunoglobulins (IgG like protein) also increased after vaccination. Using immunoblotting the CDV specific IgG-like protein reacted with a CDV protein, having a molecular weight of approximately 75 kDa.

Interleukin-6 and its relationship to C-reactive protein and fever in children with febrile neutropenia

The assessment of febrile neutropenia is problematic. C-reactive protein (CRP) values alone do not differentiate those patients with microbiologically documented infections from those with unexplained fevers. Plasma interleukin-6 (IL-6), measured by ELISA, was correlated with different diagnostic groups in 47 episodes of febrile neutropenia in children. Samples were collected daily from admission until resolution of fever. On admission, the median IL-6 value for gram-negative infections was 1610 pg/ml (range, 896-40,000), for gram-positive infections it was 138 pg/ml (range, 66-1045), and for unexplained fevers it was 50 pg/ml (range, 24-135, with a single high value of 665 pg/ml). These medians were significantly different (P less than .005). There was no significant difference in median CRP values. IL-6 values peaked 24-48 h before CRP values. There was a positive correlation of IL-6 with the presence of fever. Plasma IL-6 may be a more sensitive marker than CRP of acute infection and should prove useful in the assessment of fevers in these patients.

Effect of metals on interleukin-6 (IL-6) mitogenic stimulation of murine hybridoma cells

The effect of several divalent metal cations (Co, Cu, Zn, Hg and Pb) on the proliferative response of B9 hybridoma cells to IL-6 has been investigated. At concentrations which are not cytotoxic all the metals inhibited proliferation. The inhibition by Cd and Pb was dependent on both time of addition of the metal and IL-6 concentration. Cd (10 microM) and Pb (50 microM) added at the same time as IL-6 were inhibitory but added 24h later had no effect. Increasing the concentration of IL-6 overcame the inhibitory effect of Cd (10 microM) and Pb (50 microM). Inhibition caused by the other metals was independent of either time of addition or IL-6 concentration. IL-6 did not stimulate an increased intracellular concentration of metallothionein suggesting that the protective effect of IL-6 is not mediated via induction of metallothionein. The results suggest that there are at least two distinct metal sensitive events in B9 proliferation, i) IL-6 reversible inhibition by Cd and Pb ii) IL-6 independent inhibition by Co, Cu and Hg.

Insulin modulation of acute-phase protein production in a human hepatoma cell line

Insulin is widely used as a growth factor in hepatocyte culture but its effect on the production of acute-phase proteins has not been studied. By measuring four positive (fibrinogen, alpha 1-antitrypsin, alpha 1-acid glycoprotein, and alpha 1-antichymotrypsin) and four negative (albumin, prealbumin, transferrin, and retinol binding protein) acute-phase proteins produced by the Hep G2 hepatoma cell line, we have shown that insulin is an important modulator of acute-phase protein production. Our data show that insulin is able to inhibit the synthesis of prealbumin, transferrin, and fibrinogen. The results also show a complex interaction between insulin, interleukin 6, and glucocorticoids because insulin is able to inhibit the dexamethasone induction of alpha 1-antichymotrypsin, and in the presence of interleukin 6, dexamethasone is able to regulate the production of fibrinogen and prealbumin. The regulatory role of insulin in fibrinogen production was confirmed by pulse chase labeling followed by immunoprecipitation and fluorography.

Psychostimulant effects on academic and behavioral measures for ADHD junior high school students in a lecture format classroom

This study evaluated the effects of two doses of psychostimulants on nine ADHD students' performance in a classroom designed to be analogous to a junior high school American history class conducted during a summer treatment program. Double-blind, placebo-controlled assessment revealed significant and clinically important effects of psychostimulants on quiz and test performance, observations of attention and behavior during lectures, and teacher ratings, as well as accuracy on assignments completed during study hall. Analysis of individual differences revealed a 66% positive response rate. The implications for use of psychostimulants with ADHD young adolescents are discussed.

A qualitative and serial analysis of social problem solving in aggressive boys

Social problem solving skills in 84 elementary school aged boys were assessed to identify those responses most salient in the prediction of ratings of aggressive and socially withdrawn behavior. Aggressive and socially withdrawn boys did not differ from the control group in the number of effective first solutions generated to the hypothetical stories. The control group generated significantly more effective solutions as second alternatives to the stories than did the aggressive or socially withdrawn boys. In addition, the number of effective second responses generated significantly predicted both aggression and social withdrawal after controlling for verbal problem solving. Results are discussed in terms of differences in cognitive processes as well as implications for treatment.

Alpha 2 macroglobulin state in acute pancreatitis. Raised values of alpha 2 macroglobulin-protease complexes in severe and mild attacks

Plasma values of C reactive protein, alpha 1 proteinase inhibitor, alpha 2 macroglobulin, and complexed alpha 2 macroglobulin have been determined in serial samples from 27 patients with acute pancreatitis. Complexed alpha 2 macroglobulin was measured by a novel enzyme linked immunosorbent assay with a monoclonal antibody specific for the complexed form. Patients with severe illness had lower concentrations of total alpha 2 macroglobulin and higher concentrations of complexed alpha 2 macroglobulin than those with mild illness, and in the majority of severe attacks the abnormal amounts of complexed alpha 2 macroglobulin were present throughout the eight days of the study. The proportion of total alpha 2 macroglobulin in the uncomplexed form, however, was generally greater than 90%, and in 26% of the mild cases completely normal concentrations of uncomplexed alpha 2 macroglobulin (greater than 99% of total) were found throughout the eight days of the study. This suggests that exhaustion of alpha 2 macroglobulin in plasma is unlikely to be a major factor in the pathogenesis of acute pancreatitis.

Is fatal pancreatitis a consequence of excessive leukocyte stimulation? The role of tumor necrosis factor alpha

This study examines the possible role of excessive leukocyte stimulation in the pathogenesis of acute pancreatitis. Levels of tumor necrosis factor alpha (TNF-alpha) and elastase-alpha 1 proteinase inhibitor (E-alpha 1PI) have been measured as markers of macrophage and neutrophil activation, respectively, in serial plasma samples from 27 patients with acute pancreatitis. Levels of TNF-alpha did not support the possibility of excessive macrophage activation, but raised levels of E-alpha 1PI in patients with either the mild or severe form of the illness indicated the activation of neutrophils. Whether this is a consequence of the illness or is a contributory factor in the pathogenesis is not clear.

Interleukin-2 regulation of diadenosine 5',5'''-p1 p4-tetraphosphate (Ap4A) levels and DNA synthesis in cloned murine T lymphocytes

The levels or diadenosine 5', 5'''-p1, p4, tetraphosphate (Ap4A), a putative signal molecule associated with DNA synthesis, has been measured in murine T lymphocytes. The level or Ap4A detected correlated with the stimulation of DNA synthesis in murine T lymphocytes. In interleukin-2 (IL-2) dependent cells previously deprived of IL-2, new DNA synthesis can be induced by adding IL-2; the synthesis of DNA is preceded by an increase in Ap4A levels. A significant increase in DNA synthesis was observed after the Ap4A concentration exceeded the Kd of DNA polymerase alpha for Ap4A. Similarly, in cells blocked from synthesizing DNA by hydroxyurea, the levels or Ap4A are maintained only in the presence of IL-2. Once IL-2 is removed, the potential to synthesize DNA decreases and is preceded by decreases in the level or Ap4A. The DNA synthesis potential decreases rapidly after the Ap4A concentration fell below the Kd of DNA polymerase alpha for Ap4A. It is possible that Ap4A is a second messenger molecule required for the proliferation of lymphocytes and that the production of Ap4A in IL-2 dependent murine T lymphocytes is regulated by the homologous growth factor.

Cytokines in disease

Cytokines are peptides used by immune and inflammatory cells to communicate with each other and to control the milieu interieur in which they operate. Recent evidence suggests that they are of immense importance in controlling the local and systemic events of the immune response, inflammation, hemopoiesis, healing, and the systemic response to injury. Many of them can now be measured by immunoassay, and the role of such measurements in the diagnosis and management of disease is actively under investigation. Similarly, the availability of recombinant DNA techniques to produce cytokines in almost unlimited quantities is leading to new and exciting therapeutic applications.

Cytokines in disease

Cytokines are peptides used by immune and inflammatory cells to communicate with each other and to control the milieu interieur in which they operate. Recent evidence suggests that they are of immense importance in controlling the local and systemic events of the immune response, inflammation, hemopoiesis, healing, and the systemic response to injury. Many of them can now be measured by immunoassay, and the role of such measurements in the diagnosis and management of disease is actively under investigation. Similarly, the availability of recombinant DNA techniques to produce cytokines in almost unlimited quantities is leading to new and exciting therapeutic applications.

Interleukin-6 and ACTH act synergistically to stimulate the release of corticosterone from adrenal gland cells

We investigated whether interleukin-6 (IL-6) could cause the release of corticosterone by a direct interaction with the adrenal gland. Primary cultures of rat adrenal glands were obtained by dispersion with collagenase and incubated for 24 h with different doses of IL-6. Levels of corticosterone were measured by competitive protein binding assay. A significant (P less than 0.025) dose-dependent increase in corticosterone levels was seen at all doses used. Time course experiments demonstrated that IL-6 stimulated corticosterone release over a period of 24 h but not after 12 or 3 h. The stimulation of adrenal cells with different doses of ACTH1-24 and 40 U/ml of IL-6 showed a synergistic effect when IL-6 was combined with low concentrations of ACTH1-24 (2 and 20 pmol/l). This effect was not evident at higher doses. Our results suggest that IL-6 may act at different levels of the hypothalmic pituitary adrenal axis. Moreover the finding of a synergistic effect with ACTH1-24 indicates that IL-6 could play a role in the long term response to stress.

Measurement of the 'fast' or complexed form of alpha 2 macroglobulin in biological fluids using a sandwich enzyme immunoassay

A sandwich enzyme immunoassay has been developed for measuring the 'fast' or complexed form of alpha 2 macroglobulin using a complex-specific monoclonal antibody. The working range of this assay is 1.5-15 micrograms/l and is suitable for use with various biological fluids. Using this assay the normal plasma levels were found to range from 4.2 mg/l to 14.4 mg/l (0.17%-0.70% of total alpha 2 macroglobulin) with a mean value of 7.6 mg/l +/- 2.6 (0.37% +/- 0.12% of total alpha 2 macroglobulin). Elevated levels were seen in plasma samples taken on the day of admission from patients with acute pancreatitis and in some synovial fluid samples from patients with various arthritides.

Measurement of plasma concentrations of polymorphonuclear elastase-alpha 1 proteinase inhibitor (elastase-alpha 1 antitrypsin) in patients with rheumatoid arthritis: interference by rheumatoid factor

The plasma concentration of granulocyte elastase in complex with alpha 1 proteinase inhibitor was determined in 32 patients with rheumatoid arthritis and eight with seronegative spondarthritis complicated by peripheral joint synovitis. Most patients had concentrations of complex which were within the range of the control group when measured by an 'in-house' enzyme linked immunosorbent assay, though several of the patients with rheumatoid arthritis had raised concentrations. When the complexes were measured by a commercially available assay, however, much higher values were obtained for many of the patients with rheumatoid arthritis. Evidence is presented indicating that the commercially available assay may suffer seriously from interference by rheumatoid factor. The possibility is discussed that most patients with rheumatoid arthritis may have plasma concentrations of elastase-alpha 1 PI which are normal or only slightly raised, and that previously published reports using assay systems similar to that available commercially might also have produced falsely raised values for many individuals with rheumatoid arthritis.

B cell function in acquired "common-variable" hypogammaglobulinemia: proliferative responses to lymphokines

We have compared the proliferative responses of an enriched population of B lymphocytes from patients with acquired (common variable) hypogammaglobulinemia (CVH) with the responses of cells from normal individuals. The uptake of [3H]thymidine into DNA was measured on stimulation with a range of interleukins (IL-2, IL-4, and IL-6) and solid-phase anti-IgM. Flow cytometry using CD19 and surface IgM showed that the "non-T" preparations from the peripheral blood of CVH patients either contained B cells within the normal range (30-40% of the cells) or in a minority group no B cells (less than 3% of the cells). Overall, there were no significant differences between the proliferative responses of patients' cells (in the group where normal numbers of B cells were present) and normal cells with any combination of stimulus used. No IgG was produced by cells from any patient and in only one patient was IgM production observed. This suggests that the primary B lymphocyte defect in CVH is in the differentiation phase in B cell function rather than in the growth phase. However, the presence or absence of B cells suggests that different defects exist in subgroups of patients with this disease.

Molecular events associated with the action of haemopoietic growth factors

Haemopoietic growth factors stimulate a number of consensus biochemical and molecular events regardless of the specificity detailed by unique ligand and receptor structures. Analysis of three distinct colony stimulating factors, CSFs (IL-3, G-CSF, GM-CSF) and the lymphocytotropic growth factor IL-2 reveal remarkable similar distal subcellular biochemical signals although initial membrane 'signal transduction' may differ significantly. Both early progenitor cell growth factors, such as IL-3, and late acting factors such as CSF-1, stimulate tyrosine and serine-threonine substrate phosphorylations. One substrate (p68) is phosphorylated by many CSF stimulants, including IL-2, suggesting a highly conserved role in many unique receptor(s) signal transduction processes. The proliferative CSFs and IL-2 also stimulate the expression of many of the same genes including proto-oncogenes, ornithine decarboxylase and members of the ancient family of stress response genes. Although initial membrane events may differ among the respective proliferative stimulants, biochemical and molecular convergence on highly conserved cellular substrates and the programme of gene expression is seen.

Effects of anti-proliferative cyclic AMP on interleukin 2-stimulated gene expression

Elevation of intracellular cyclic adenosine 3':5' monophosphate (cAMP) inhibits interleukin 2 (IL-2)-stimulated proliferation of a murine cytotoxic cell clone, CT6. The effects of antiproliferative dosages of stable cAMP-derivative, 8-bromoadenosine 3':5'-monophosphate (8-Br-cAMP), on steady state mRNA expression stimulated by IL-2 was examined. IL-2 stimulated mRNA accumulation of three nuclear proto-oncogenes c-fos, c-myc, and c-myb. 8-Br-cAMP alone stimulated c-fos, c-myb, and IL-2 receptor mRNA accumulation as determined by Northern blot analysis. 8-Br-cAMP, however, markedly inhibited c-myc expression stimulated by IL-2. Furthermore, although c-fos and IL-2 receptor mRNA expression was potentiated by 8-Br-cAMP, suppression of protein synthesis was seen. We show that antiproliferative cAMP stimulates similar mRNA expression as does IL-2, with the exception of c-myc. Although a comparative stimulation of steady state mRNA accumulation of some genes occurs, cAMP may profoundly effect protein synthesis. cAMP, therefore, acts on multiple targets involved in the macromolecular events stimulated by IL-2.

Effects of anti-proliferative cyclic AMP on interleukin 2-stimulated gene expression

Elevation of intracellular cyclic adenosine 3':5' monophosphate (cAMP) inhibits interleukin 2 (IL-2)-stimulated proliferation of a murine cytotoxic cell clone, CT6. The effects of antiproliferative dosages of stable cAMP-derivative, 8-bromoadenosine 3':5'-monophosphate (8-Br-cAMP), on steady state mRNA expression stimulated by IL-2 was examined. IL-2 stimulated mRNA accumulation of three nuclear proto-oncogenes c-fos, c-myc, and c-myb. 8-Br-cAMP alone stimulated c-fos, c-myb, and IL-2 receptor mRNA accumulation as determined by Northern blot analysis. 8-Br-cAMP, however, markedly inhibited c-myc expression stimulated by IL-2. Furthermore, although c-fos and IL-2 receptor mRNA expression was potentiated by 8-Br-cAMP, suppression of protein synthesis was seen. We show that antiproliferative cAMP stimulates similar mRNA expression as does IL-2, with the exception of c-myc. Although a comparative stimulation of steady state mRNA accumulation of some genes occurs, cAMP may profoundly effect protein synthesis. cAMP, therefore, acts on multiple targets involved in the macromolecular events stimulated by IL-2.

Identification of a signal-transduction pathway shared by haematopoietic growth factors with diverse biological specificity

The haematopoietic growth factors multi-colony-stimulating factor, granulocyte/macrophage colony-stimulating factor, granulocyte colony-stimulating factor and interleukin 2 specifically control the production and proliferation of distinct leucocyte series. Each growth factor acts on a unique surface receptor associated with an appropriate signal-transduction apparatus. In this report we identify a 68 kDa substrate which is phosphorylated after stimulation of different cell types with multi-colony-stimulating factor, granulocyte colony-stimulating factor and interleukin 2. The 68 kDa substrate is also phosphorylated in each cell line stimulated with synthetic diacylglycerol, a direct activator of protein kinase C. Interestingly, granulocyte/macrophage colony-stimulating factor does not induce phosphorylation of the 68 kDa molecule. The 68 kDa molecule that is phosphorylated after stimulation with each ligand yielded similar peptide maps after chymotryptic digestion; furthermore, the substrate was always phosphorylated on threonine residues. Phosphorylation of the same residues in the 68 kDa substrate suggests that activation of protein kinase C is one common signal-transduction event associated with the action of multi-colony-stimulating factor, granulocyte colony-stimulating factor and interleukin 2.

Identity of common phosphoprotein substrates stimulated by interleukin 2 and diacylglycerol suggests a role of protein kinase C for IL 2 signal transduction

Interleukin 2 (IL 2) is a polypeptide growth factor essential for the proliferation and differentiation of T lymphocytes, large granulocytic lymphocytes, and, potentially, cells of the antibody-producing lineage, B lymphocytes. Many of the biological properties of IL 2 may be mimicked or potentiated by a potent class of tumor promoters, phorbol esters. Phorbol esters have recently been shown to associate with and activate a unique phospholipid/Ca2+-dependent phosphotransferase, protein kinase C (PK-C). Utilizing two-dimensional gel electrophoresis, we have compared the IL 2 and diacylglycerol-induced protein phosphorylation patterns of several IL 2-dependent murine cell lines. Both IL 2 and synthetic diacylglycerol, 1-oleyl-2-acetylglycerol (OAG), stimulated phosphorylation of a number of protein substrates in intact cells compared to unstimulated controls. Three groups of substrates were identified; the first showed increased phosphorylation following stimulation with either IL 2 or OAG, while the second and third groups showed increased phosphorylation following stimulation with IL 2 but not OAG, and with OAG but not IL 2, respectively. Here, we characterize the kinetics of phosphorylation of one cellular substrate, p68, which appears to be phosphorylated in response to direct activators of PK-C or lymphoid or myeloid growth factors in their respective lineage cell lines. The observation that IL 2 also stimulates a unique series of phosphoproteins in addition to those induced by direct PK-C activators suggests that IL 2 may initiate additional protein kinase activities, unrelated to PK-C, which may also be critical for the ligand-receptor signal transduction process regulating growth and gene expression.

Interleukin 2 and diacylglycerol stimulate phosphorylation of 40 S ribosomal S6 protein. Correlation with increased protein synthesis and S6 kinase activation

Interleukin 2 (IL-2) and the synthetic diacylglycerol, 1-oleoyl-2-acetylglycerol (OAG), a direct activator of protein kinase C, induce phosphorylation of the ribosomal S6 protein in a murine IL-2-dependent lymphocyte clone. The phosphorylation of S6 protein was correlated with increased protein synthesis in this cell line. Using cell-free assay systems, two unique kinases capable of phosphorylating the S6 protein were identified, namely, a calcium/phospholipid-dependent phosphotransferase, protein kinase C, and a second phospholipid-independent kinase detected in crude cytosolic fractions. Peptide mapping of the S6 protein demonstrated that the degree of S6 phosphorylation stimulated by IL-2 and OAG was similar to that achieved using the second (calcium/phospholipid-independent) kinase but not to the level of phosphorylation achieved with protein kinase C. The kinase responsible for phosphorylating S6 was soluble in stimulated cells and was induced in a time-dependent manner by either IL-2 or diacylglycerol treatment of intact cells. These data support the notion that, although protein kinase C is activated by IL-2 or OAG, subsequent events such as S6 phosphorylation may be the result of the activation of secondary phosphotransferase systems regulated by protein kinase C.

Generation of a murine monoclonal antibody that detects the fos oncogene product

A hybridoma producing a monoclonal antibody (MoAB) recognizing both the cellular and viral forms of fos has been generated by somatic cell hybridization techniques from spleen cells of mice immunized with a synthetic peptide corresponding to amino acids 128-152, a consensus region, of both the v-fos and c-fos oncogene products. Three proteins with molecular weights of 55,000, 44,000, and 42,000 were detected by immunoblotting. While MoAB 2G9C3 failed to immunoprecipitate fos from Finkel-Biskis-Jenkins murine osteosarcoma-virus-infected fibroblasts, both the 55,000 v-fos protein and the 39,000 cellular protein were coprecipitated using polyvalent rabbit antibodies to the same peptide. Whereas no cell surface membrane expression of fos was detected, after membrane permeabilization by a brief exposure to lysolecithin it was possible to specifically detect internal fos by immunofluorescence flow cytometry. Immunohistochemical staining of FBJ virus-infected cells revealed intense, nuclear staining.

Stimulation of specific GTP binding and hydrolysis activities in lymphocyte membrane by interleukin-2

Interleukin-2 (IL-2) is a polypeptide growth factor which stimulates the proliferation and differentiation of T lymphocytes. The receptor for IL-2 is expressed on activated T lymphocytes, cloned IL-2 dependent cells and several other cell types. Analysis of the primary structure and of immune-precipitated receptor suggests that this molecule has no intrinsic signal transduction function, unlike other growth factors. IL-2 interaction with a high affinity receptor has been shown, however, to activate the calcium/phospholipid-dependent protein kinase C (PK-C) presumably via phosphoinositide hydrolysis. Members of a family of closely related guanine nucleotide binding proteins (G proteins) regulate a diverse group of metabolic events. Two of them, Gs and Gi, stimulate and inhibit adenylate cyclase activity respectively, and other G proteins are involved in diverse signal transduction system. Another member, Go, has no known function and activation of phospholipase C has been attributed to the action of an unidentified G protein, Gp. Since it has been observed that IL-2 inhibits the catalytic activity of adenylate cyclase and that agents such as PGE2 which stimulate adenylate cyclase activity inhibit the lymphoproliferative response to IL-2, association of GTP binding proteins with IL-2 signal transduction was investigated. In this report we describe for the first time the participation of a GTP binding protein in the action of a polypeptide growth factor, interleukin-2.

Multilineage hematopoietic growth factor interleukin 3 and direct activators of protein kinase C stimulate phosphorylation of common substrates

In order to investigate early signal transduction events in myeloid cells, the phosphosubstrates of an interleukin 3 (IL 3)-dependent cell line, FDC-P1, have been analyzed. Using synthetic diacylglycerol as a direct activator of the unique calcium-phospholipid-dependent phosphotransferase protein kinase C (PK-C) and genetically engineered homogeneous IL 3, we have demonstrated a common element to signal transduction events associated with these stimulants. One novel substrate, p68 (68,000 kd), was rapidly phosphorylated in either IL 3- or diacylglycerol-stimulated cells. The phosphorylation of p68 was dose-dependent, with both the physiological ligand and diacylglycerol inducing the same maximal level of phosphorylation. Phosphorylation of p68 occurred in a time-dependent manner analogous to previously described kinetics of PK-C subcellular redistribution in the FDC-P1 cell line. The p68 substrate was also phosphorylated in a cell-free system under conditions designed to activate PK-C. Phosphoamino acid analysis demonstrated that the p68 molecule phosphorylated in intact cells as well as in a calcium-phospho-lipid-dependent cell-free system was phosphorylated on threonine residues, not tyrosine. These data support the hypothesis that the activation of PK-C that occurs after IL 3-receptor interaction which leads to the rapid phosphorylation of cellular proteins is an important element of the signal transduction mechanism in FDC-P1 cells. We propose that phosphorylation of the p68 molecule is a physiochemical marker for the activation of PK-C in myeloid cells, in response to the growth-promoting physiological ligand.