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.

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 2.

Prediction of the difficulty of an airway is unreliable, and failure of one technique of management increases the likelihood of failure of subsequent interventions. Part 2 of this review describes strategies to avoid or mitigate the impact of failure, and the associated airway-related morbidity and mortality.

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.

Monoclonal antibody against a cross-reactive idiotypic determinant found on human autoantibodies with anti-I and -i specificities.

A monoclonal antibody has been raised against a cross-reactive idiotypic determinant expressed on human autoantibodies with anti-I and -i specificities. The McAb is directed against a conformational epitope requiring interaction of H- and L-chains for maximal expression. This epitope was strongly expressed on the monoclonal protein of one out of 100 patients with paraproteinaemia and the peripheral blood lymphocytes of one out of 50 cases of B-cell leukaemia. A small amount of the epitope is detectable among immunoglobulins in normal serum.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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).