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1.
Psychol Health ; : 1-18, 2022 Feb 14.
Article in English | MEDLINE | ID: mdl-35156467

ABSTRACT

OBJECTIVE: This study applied the theory of reasoned goal pursuit (TRGP) in predicting physical activity among Australian undergraduate students, providing the first empirical test of the model.Methods: The research comprised an elicitation study (N = 25; MAge= 25.76, SDAge= 11.33, 20 female, 5 male) to identify readily accessible procurement and approval goal beliefs and behavioural, normative, and control beliefs; and, a two-wave prospective online survey study (N = 109; MAge = 21.88, SDAge = 7.04, 63 female, 46 male) to test the tenets of the TRGP in relation to meeting World Health Organization physical activity guidelines during the COVID-19 pandemic among first year university students.Results: A linear PLS-SEM model displayed good fit-to-data, predicting 38%, 74%, and 48% of the variance in motivation, intention, and physical activity, respectively. The model supported the majority of hypothesised pattern of effects among theory constructs; in particular, the proposition that beliefs corresponding to procurement and approval goals would be more consequential to people's motivation and, thus, their intentions and behaviour, than other behavioural and normative beliefs, respectively.Conclusions: Results lend support for the TRGP and sets the agenda for future research to systematically test the proposed direct, indirect, and moderation effects for different health behaviours, populations, and contexts.Supplemental data for this article is available online at https://doi.org/10.1080/08870446.2022.2026946 .

2.
J Exp Med ; 159(3): 964-9, 1984 Mar 01.
Article in English | MEDLINE | ID: mdl-6699546

ABSTRACT

Virus-related oncogenes have been demonstrated in human tumor cells and may play a role in neoplastic transformation. Cancerous effusions contain inhibitors of monocyte function and are absorbed by monoclonal antibodies to the immunosuppressive retroviral structural protein, P15E. We therefore examined eight human malignant cell lines for P15E-related antigens, by indirect immunofluorescence. Up to 87% of fixed malignant cells were reactive with two different monoclonal anti-P15E antibodies, while under identical conditions approximately 7% of freshly isolated human mononuclear cells were positive. Differentiation of two tumor cell lines with dibutyryl cyclic AMP resulted in decreased anti-P15E reactivity. Blast transformation of human mononuclear cells with mitogens induced reactivity with anti-P15E. Thus human malignant and blast-transformed cells contain antigens related to P15E. Expression of this viral-related gene may occur during rapid cell division and be abnormally regulated in cancer cells, thus rendering them more resistant to immune destruction.


Subject(s)
Antigens, Viral/immunology , Cell Transformation, Neoplastic/immunology , Lymphocyte Activation , Lymphocytes/immunology , Viral Envelope Proteins/immunology , Animals , Antibodies, Monoclonal/immunology , Antibodies, Viral/immunology , Antigens, Viral/genetics , Cell Line , Cell Transformation, Neoplastic/pathology , Humans , Mice , Mitogens/pharmacology , Retroviridae/genetics , Retroviridae/immunology , Viral Envelope Proteins/genetics
3.
Br J Anaesth ; 112(1): 171-2, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24318702
4.
Br J Anaesth ; 102(6): 768-74, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19398453

ABSTRACT

BACKGROUND: With the proliferation of practice guidelines in anaesthesia comes the possibility that anaesthetists may, during the course of their work, commit 'violations' (actions that are not intended to cause harm to patients, but that deviate from guidelines). These may have a long-term impact on patient safety, and so there is a need to understand what makes anaesthetists decide to follow or deviate from guidelines. METHODS: A questionnaire on the use of guidelines was completed by 629 College Fellows. This presented three anaesthetic scenarios, each of which involved a deviation from a guideline, and asked respondents to rate their beliefs about the likely outcome of the violation, the level of social approval they would have for violating, the amount of control they would have over violating, and the practice of their peers with regard to violating. RESULTS: In all three scenarios, beliefs about the outcome of violating and the amount of control over violating predicted respondents' self-reported likelihood that they would commit the violation. In two scenarios, beliefs about the practice of peers predicted violating. Level of social approval predicted violating in one scenario only. CONCLUSIONS: Anaesthetists' decisions to follow or deviate from guidelines are influenced by the beliefs they hold about the consequences of their actions, the direct or indirect influence of others, and the presence of factors that encourage or facilitate particular courses of action.


Subject(s)
Anesthesia/standards , Anesthesiology/standards , Attitude of Health Personnel , Guideline Adherence/statistics & numerical data , Motivation , Practice Guidelines as Topic , Adult , Aged , Decision Making , Female , Humans , Male , Medical Staff, Hospital/psychology , Medical Staff, Hospital/standards , Middle Aged , United Kingdom
5.
Br J Anaesth ; 100(3): 333-43, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18238839

ABSTRACT

BACKGROUND: Despite a growing recognition of the role of human error in anaesthesia, it remains unclear what should be done to mitigate its effects. We addressed this issue by using task analysis to create a systematic description of the behaviours that are involved during anaesthesia, which can be used as a framework for promoting good practice and highlight areas of concern. METHODS: The task steps involved in preparing and delivering anaesthesia were identified using hierarchical task analysis (HTA). The systematic human error reduction and prediction approach (SHERPA) was then used to identify potential human errors at each task step and suggest ways of preventing these errors. RESULTS: The number and type of behaviours involved vary according to the 'phase' of anaesthesia, with tasks in the induction room, including induction of anaesthesia itself, being the most demanding. Errors during preoperative planning and perioperative maintenance could be avoided by measures to support information handling and decision-making. Errors during machine checking, induction, and emergence could be reduced by streamlining or automating task steps, or by making changes to the physical design of the work environment. CONCLUSIONS: We have demonstrated the value of task analysis in improving anaesthetic practice. Task analysis facilitates the identification of relevant human factors issues and suggests ways in which these issues can be addressed. The output of the task analysis will be of use in focusing future interventions and research in this area.


Subject(s)
Anesthesia/methods , Clinical Competence , Task Performance and Analysis , Anesthesia/standards , Anesthesia Recovery Period , England , Humans , Intraoperative Care/methods , Intraoperative Care/standards , Medical Errors/prevention & control , Preoperative Care/methods , Preoperative Care/standards , Risk Management/methods
6.
Domest Anim Endocrinol ; 34(3): 269-77, 2008 Apr.
Article in English | MEDLINE | ID: mdl-17897805

ABSTRACT

In this study the hypothesis that irreversible glucose loss results in an 'uncoupling' of the somatotrophic axis (increasing plasma GH levels and decreasing plasma IGF-I) was tested. During periods of negative energy balance the somatotrophic axis respond by increasing plasma GH and decreasing plasma IGF-I levels. In turn, elevated GH repartitions nutrient by increasing lipolysis and protein synthesis, and decreases protein degradation. Irreversible glucose loss was induced using sub-cutaneous injections of phloridizin. Seven non-lactating cows were treated with 8g/day phloridizin (PHZ) and seven control animals (CTRL, 0g/day), while being restricted to a diet of 80% maintenance. PHZ treatment increased urinary glucose excretion (P<0.001), resulting in hypoglycemia (P<0.001). As a response to this glucose loss, the PHZ treated animals had elevated plasma NEFA (P<0.005) and BHBA (P<0.001) levels. Average plasma insulin concentrations were not altered with PHZ treatment (P=0.059). Plasma GH was not different between the two groups (P>0.1), whereas plasma IGF-I levels decreased significantly (P<0.001) with PHZ treatment. The decline in plasma IGF-I concentrations was mirrored by a decrease in the abundance of hepatic IGF-I mRNA (P=0.005), in addition the abundance of hepatic mRNA for both growth hormone receptors (GHR(tot) and GHR(1A)) was also decreased (P<0.05). Therefore, the irreversible glucose loss resulted in a partial 'uncoupling' of the somatotrophic axis, as no increase in plasma GH levels occurred although plasma IGF-I levels, hepatic IGF-I mRNA declined, and the abundance of liver GH receptor mRNA declined.


Subject(s)
Adaptation, Physiological/physiology , Cattle Diseases/metabolism , Glucose/metabolism , Malnutrition/veterinary , 3-Hydroxybutyric Acid/blood , Animals , Cattle , Fatty Acids, Nonesterified/blood , Female , Glycosuria/veterinary , Growth Hormone/blood , Hypoglycemia/veterinary , Insulin-Like Growth Factor I/analysis , Insulin-Like Growth Factor I/genetics , Lipolysis/physiology , Liver/chemistry , Malnutrition/metabolism , Phlorhizin/administration & dosage , Protein Biosynthesis/physiology , RNA, Messenger/analysis
7.
J Clin Invest ; 76(6): 2317-22, 1985 Dec.
Article in English | MEDLINE | ID: mdl-2934409

ABSTRACT

We have recently shown that human monocytes and U937 cells possess two molecular classes of Fc gamma receptor. One, a 72,000-mol-wt sialoglycoprotein, has high affinity for certain subclasses of human and murine monomeric IgG. The other is a 40,000-mol-wt protein (p40) with low affinity for monomeric IgG but with the capacity to bind IgG aggregates or IgG-coated particles. In the present study, a 40,000-mol-wt single chain protein, apparently identical to p40 from U937 cells, was isolated from surface-radioiodinated human platelets by affinity purification using a murine IgG2b monoclonal antibody to p40. This 40,000-mol-wt protein was not seen when control IgG2b or unrelated murine monoclonal antibodies were employed in place of anti-p40. The same 40,000-mol-wt protein was also recovered from an IgG-Sepharose affinity adsorbent, but not from ovalbumin-or myoglobin-Sepharose. The 72,000-mol-wt Fc gamma receptor of monocytes was not identified on platelets. Monoclonal anti-p40 and Fab fragments derived from this antibody blocked platelet aggregation by heat-aggregated human IgG, whereas a control murine IgG2b protein had little or no inhibitory effect at 500-1,000-fold higher concentrations. A murine IgG1 monoclonal antibody, reactive with an unrelated platelet-specific membrane antigen, did not inhibit platelet responses to aggregated IgG. Anti-p40 did not affect platelet aggregation by thrombin, collagen, or fibrinogen plus ADP. Although anti-p40 did not directly aggregate platelets in the concentrations employed, cross-linking with F(ab')2 goat anti-murine Ig induced apyrase-sensitive aggregation of anti-p40-treated platelets. This indicates that p40 possesses transmembrane linkage for platelet activation and secretion. These observations strongly suggest that this newly recognized 40,000-mol-wt platelet membrane protein serves as an Fc gamma receptor.


Subject(s)
Blood Platelets/metabolism , Immunoglobulin G/metabolism , Monocytes/metabolism , Receptors, Fc/metabolism , Antibodies, Monoclonal , Blood Platelets/immunology , Humans , Membrane Proteins/immunology , Membrane Proteins/metabolism , Molecular Weight , Monocytes/immunology , Receptors, IgG
8.
Biochim Biophys Acta ; 1133(3): 275-85, 1992 Feb 03.
Article in English | MEDLINE | ID: mdl-1737061

ABSTRACT

Necrosis and apoptosis are two distinct modes of cell death which differ in morphology, mechanism and incidence. Membrane disruptants, respiratory poisons and hypoxia cause ATP depletion, metabolic collapse, cell swelling and rupture leading to inflammation. These are typical features of necrosis. Apoptosis plays a crucial role in embryogenesis and development and is also prevalent in tumours. It is characterised by cell shrinkage, chromatin condensation and systematic DNA cleavage. Apoptotic cells are rapidly engulfed by phagocytes, thus preventing inflammatory reaction to degradative cell contents. In vivo, apoptosis is almost impossible to quantify due to problems of heterogeneity and the short half-life of an apoptotic cell. In vitro, mechanistic studies are further complicated by a late phase of apoptosis where the cell membrane becomes permeable to vital dyes and which occurs in the absence of phagocytes. Here we describe a novel and rapid multiparameter flow cytometric assay which discriminates and quantifies viable, apoptotic and necrotic cells via measurement of forward and side light scatter (proportional to cell diameter and internal granularity, respectively) and the DNA-binding fluorophores Hoechst 33342 and propidium. It is anticipated that mechanistic studies of apoptosis in a variety of cell types will greatly benefit from this mode of analysis.


Subject(s)
Cell Death , Flow Cytometry/methods , Necrosis , Animals , Benzimidazoles , Burkitt Lymphoma/pathology , Cells, Cultured , Fluorescent Dyes , Immunoglobulin G/metabolism , Liver/cytology , Methylprednisolone/pharmacology , Rats , Scattering, Radiation , Thymus Gland/cytology , Thymus Gland/drug effects
9.
Cell Signal ; 8(2): 141-9, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8730516

ABSTRACT

Both large- and small-conductance chloride (Cl-) channels have been found in human T lymphocytes; however, apart from possible roles in mediating regulatory volume decrease, their functions are not understood. We have used patch-clamp electrophysiology, Ca2+ spectrofluorometry, and Western blot assay for phosphotyrosine to investigate the effects of blocking Cl- channels on proliferation and on specific events in the activation of normal human T cells. Four chemically distinct Cl- channel blockers inhibited both the small-conductance Cl- channels and phytohemagglutinin (PHA)-induced lymphocyte proliferation in a similar dose-dependent manner; their order of potency was 5-nitro-2(3-phenylpropylamino)-benzoic acid (NPPB) > 4,4'-diisothiocyano-2,2'-disulfonic acid (DIDS) > flufenamic acid >> IAA-94. The Cl- channel blockers inhibited both the PHA-induced mobilization of Ca2+ and the rapid tyrosine phosphorylation of several polypeptides. Cell proliferation was not rescued by the Ca+ ionophore ionomycin or by addition of exogenous interleukin-2 (IL-2). Moreover, the blockers also inhibited phosphotyrosine expression in IL-2-treated, activated lymphoblasts. Thus, our results support a role for Cl- channels in early, PHA-evoked signalling and in later, II-2-dependent stages of lymphocyte activation and proliferation.


Subject(s)
Chloride Channels/antagonists & inhibitors , Lymphocyte Activation/physiology , Signal Transduction/immunology , T-Lymphocytes/physiology , Blotting, Western , Calcium/physiology , Cell Division/drug effects , Cell Division/immunology , Dose-Response Relationship, Immunologic , Humans , Immunosuppressive Agents/pharmacology , Interleukin-2/pharmacology , Patch-Clamp Techniques , Phosphorylation , Spectrometry, Fluorescence , T-Lymphocytes/chemistry , T-Lymphocytes/cytology , Tyrosine/metabolism
10.
Water Sci Technol ; 52(3): 29-36, 2005.
Article in English | MEDLINE | ID: mdl-16206841

ABSTRACT

A Hydrodynamic Vortex Separator (HDVS) has been modelled using Computational Fluid Dynamics (CFD) in order to predict the residence time of the fluid at the overflow and underflow outlets. A technique which was developed for use in Heating, Ventilation and Air Conditioning (HVAC) was used to determine the residence time and the results have been compared with those determined experimentally. It is shown that in using CFD, it is possible to predict the mean residence time of the fluid and to study the response to a pulse injection of tracer. It is also shown that it is possible to apply these techniques to predict the mean survival rate of bacteria in a combined separation and disinfection process.


Subject(s)
Computer Simulation , Disinfection/methods , Bacteria/growth & development , Rheology , Time Factors
11.
AIDS ; 10(11): 1191-8, 1996 Sep.
Article in English | MEDLINE | ID: mdl-8883579

ABSTRACT

OBJECTIVE: We examined the effect of HIV infection on src-family protein tyrosine kinase (PTK) activity to determine if alterations in src-family PTK activity could contribute to the HIV-related chronic immune system activation observed in patients infected with HIV. METHODS: Jurkat, a CD4+ human T lymphocyte cell line was infected with HIV IIIB. Kinase activity was determined by in vitro immune complex kinase assays using antibodies specific for the src-family PTKs, p56lck, p59fyn and p60c-src expressed in T lymphocytes. PTK protein and total phosphotyrosine levels were assessed by Western blotting. The role of the gp120-CD4-Lck interaction in HIV-related PTK activation was determined using gp 120-treated Jurkat cells and HIV-infection of JCaM 1.6 cells, a Jurkat-derived cell line that lacks p56lck. RESULTS: Cells infected with HIV for 24 h exhibited increased levels of total tyrosine phosphorylation and enhanced src-family PTK activity without altered levels of expression of src-family kinases. The activity of Lck and Fyn was enhanced within 30 min of infection. HIV-related src-family PTK activation was not a function of the gp120-CD4-Lck interaction and occurred in the presence of 10 mmol/l zidovudine indicating that reverse transcriptase and activation of the HIV genome is not required. CONCLUSIONS: HIV-related activation of src-family PTK is a response of the cell to early stages of the virus life cycle, possibly either membrane fusion or viral uncoating. These results indicate that endogenous src-family PTKs may play a role in HIV-related immune activation and dysfunction. Moreover, activation of src-family PTK may be a mechanism used by the virus to facilitate some aspect of its own life cycle.


Subject(s)
HIV-1/physiology , src-Family Kinases/metabolism , Catalysis , Enzyme Activation , HIV Envelope Protein gp120/metabolism , HIV Reverse Transcriptase/metabolism , Humans , Jurkat Cells , Kinetics , Phosphotyrosine/metabolism
12.
J Immunol Methods ; 135(1-2): 121-8, 1990 Dec 31.
Article in English | MEDLINE | ID: mdl-2273252

ABSTRACT

An ELISA measuring total Ig antibodies to the capsular polysaccharide of Haemophilus influenzae type b (HbPs) in human sera using an antigen composed of Haemophilus b oligosaccharides conjugated to human serum albumin (HbO-HA) was shown to have an excellent correlation to the radioantigen binding assay (RABA). When 214 sera with different anti-HbPs levels were assayed for total Ig by HbO-HA ELISA and by RABA the correlation coefficient was 0.917 and the paired t test p value was 0.575. Use of competitive ELISA employing soluble HbPs, HbO-HA and human albumin as competitors, showed that the HbO-HA ELISA was specific for antibodies to HbPs. The HbO-HA ELISA yielded reproducible results both within and between laboratories. The HbO-HA ELISA can also be used to determine the isotype of anti-HbPs antibodies by using isotype specific enzyme conjugates. The sum of the IgG, IgA and IgM HbO-HA ELISA results had excellent correlation to the RABA results (correlation coefficient = 0.976). Thus, the HbO-HA ELISA can be substituted for the classical RABA and also be utilized for quantitating the isotype of the anti-HbPs antibodies.


Subject(s)
Antibodies, Bacterial/blood , Bacterial Vaccines/immunology , Enzyme-Linked Immunosorbent Assay/methods , Haemophilus Vaccines , Haemophilus influenzae/immunology , Polysaccharides, Bacterial/immunology , Serum Albumin/immunology , Adult , Antibodies, Bacterial/immunology , Antibody Specificity/immunology , Bacterial Capsules , Bacterial Vaccines/administration & dosage , Binding, Competitive/immunology , Child , Humans , Immunoglobulin A/analysis , Immunoglobulin G/analysis , Immunoglobulin Isotypes , Immunoglobulin M/analysis , Polysaccharides, Bacterial/administration & dosage , Radioligand Assay/methods , Reproducibility of Results , Vaccination
13.
Pediatrics ; 86(4): 527-34, 1990 Oct.
Article in English | MEDLINE | ID: mdl-2216616

ABSTRACT

A total of 268 infants aged 15 to 23 months received one dose of a vaccine composed of Haemophilus influenzae type b oligosaccharides covalently linked to the nontoxic diphtheria toxin variant CRM197 (HbOC; HibTITER). Side effects associated with vaccination were infrequent, transient, and mild. One month after a single vaccination, the anti-H influenzae type b capsular polysaccharide antibody concentration rose from a geometric mean prevaccination level of 0.20 microgram/mL to 13.77 micrograms/mL. Of these infants, 99% had a postvaccination level greater than or equal to 1.00 microgram/mL, a level associated with long-term protection. The immune response was long-lived: all of the children who were monitored 17 to 27 months after vaccination had concentrations greater than or equal to 1.00 microgram/mL. The anti-H influenzae type b capsular polysaccharide antibody generated was predominantly of the IgG isotype and IgG1 subclass. The immune sera had bactericidal activity in vitro and conferred passive protection in the infant rat meningitis model.


Subject(s)
Bacterial Vaccines/therapeutic use , Haemophilus Infections/prevention & control , Haemophilus Vaccines , Polysaccharides, Bacterial/therapeutic use , Antibody Formation , Bacterial Capsules , Bacterial Vaccines/adverse effects , Bacterial Vaccines/immunology , Clinical Trials as Topic , Haemophilus Infections/immunology , Haemophilus influenzae/immunology , Humans , Infant , Polysaccharides, Bacterial/adverse effects , Polysaccharides, Bacterial/immunology , Safety , Vaccination
14.
Pediatrics ; 85(3): 331-7, 1990 Mar.
Article in English | MEDLINE | ID: mdl-2304786

ABSTRACT

A Haemophilus influenzae type b oligosaccharide-CRM197 conjugate (HbOC) vaccine was evaluated for safety and immunogenicity in 432 infants 1 to 6 months of age. In a multicenter study involving 10 sites in six states, infants were vaccinated with three 10-micrograms doses of HbOC at 2-month intervals. Side effects associated with vaccination were mild, transient, and occurred in fewer than 2% of the subjects. More than 90% of infants of all ages responded after two doses, and more than 98% had anti-H influenzae type b capsular polysaccharide (HbPs) antibody levels greater than or equal to 1 microgram/mL after three doses. One month after the third vaccination, the geometric mean anti-HbPs antibody levels were 16.84, 26.23, and 29.11 in infants initially vaccinated at 1 to 2, 3 to 4, and 5 to 6 months of age, respectively. A long-term antibody response was observed; more than 80% of these infants had anti-HbPs levels greater than or equal to 1 microgram/mL at 2 years of age. The HbOC generated an immune response characteristic of a protein antigen; IgG anti-HbPs antibodies of IgG1 subclass predominated and the response could be boosted. The immune sera killed H influenzae type b when evaluated in an in vitro bactericidal assay. The data indicate that HbOC safely primed and boosted the immune system of young infants, providing long-lasting protective levels of anti-HbPs antibodies.


Subject(s)
Bacterial Proteins/immunology , Bacterial Vaccines/immunology , Diphtheria Toxoid/immunology , Haemophilus Vaccines , Haemophilus influenzae/immunology , Antibody Formation , Bacterial Proteins/adverse effects , Bacterial Vaccines/adverse effects , Diphtheria Toxoid/adverse effects , Humans , Immunoglobulin G/immunology , Infant , Time Factors
15.
Dev Comp Immunol ; 18(1): 13-23, 1994.
Article in English | MEDLINE | ID: mdl-8050612

ABSTRACT

An inducible hemolysin with antibacterial properties was isolated from the hemolymph of immune Galleria mellonella larvae. The Galleria-derived lysin, named Gallysin-1, was shown to have an apparent molecular weight of 75,000 and to be relatively heat stable at 56 degrees C. Although Gallysin alone was not bactericidal it caused sufficient damage of the outer cell membranes of Pseudomonas aeruginosa RP4 and Escherichia coli K176 to release beta-lactamase from the periplasm. In the presence of either purified Galleria lysozyme or egg white lysozyme Gallysin-1 had potent antibacterial activity against gram-negative bacteria. Gallysin-1 killed osmotically shocked P. aeruginosa and E. coli that suggests that it can also attack exposed inner cell membranes of gram-negative bacteria. The identification of Gallysin-1 recognizes another distinct member of the bactericidins involved in insect immunity.


Subject(s)
Hemolymph/immunology , Hemolysin Proteins/immunology , Hemolysin Proteins/isolation & purification , Moths/immunology , Animals , Cell Membrane/immunology , Escherichia coli/immunology , Molecular Weight , Muramidase/immunology , Muramidase/isolation & purification , Pseudomonas aeruginosa/immunology
16.
Dev Comp Immunol ; 11(1): 37-46, 1987.
Article in English | MEDLINE | ID: mdl-3647909

ABSTRACT

A cobra venom factor (CVF)-induced C3 convertase has been generated from the hemolymph of Galleria mellonella. CVF was immobilized on Sepharose 4B and treated with cell-free hemolymph obtained from either unvaccinated G. mellonella larvae or larvae immunized with formalized Pseudomonas aeruginosa. The C3-cleaving activity was detected by the ability to cleave the alpha-chain of bovine C3 in a manner analogous to the CVF-induced mammalian C3 convertase, CVF,Bb. The insect-derived C3 convertase formed at 28 degrees C but not at 37 degrees C, then once formed was active at both 28 degrees C and 37 degrees C. EDTA did not inhibit the formation and action of the insect derived C3 cleaving activity.


Subject(s)
Complement Activating Enzymes/biosynthesis , Complement C3-C5 Convertases/biosynthesis , Elapid Venoms/pharmacology , Lepidoptera/enzymology , Moths/enzymology , Animals , Hemolymph/drug effects , Hemolymph/enzymology , Hemolymph/immunology , Larva/enzymology , Moths/drug effects , Moths/immunology
17.
Dev Comp Immunol ; 13(2): 103-11, 1989.
Article in English | MEDLINE | ID: mdl-2506085

ABSTRACT

A hemolytic activity was identified in the hemolymph of normal and immune Galleria mellonella larvae. The hemolysin was active against sheep, human, guinea pig, and rabbit erythrocytes. Hemolysis occurred in the presence of 0.04M EDTA. Vaccination of the larvae with formalized Pseudomonas aeruginosa increased the hemolytic activity. The increase, and subsequent decline of this activity paralleled the pattern of induced in vivo antibacterial activity that is characteristic of the insect's immune response. The hemolytic activity was distinct from induced phospholipase A-like and phospholipase C-like activities that were detected in immune hemolymph and which were inhibited by EDTA. The hemolytically active material (HAM) was partially purified (apparent molecular weight range 69,000 to 75,000) and was found not to be antibacterial for P. aeruginosa. The physiological role of the HAM is as yet unknown. It is possible that it may act together with other hemolymph components to produce an immune state.


Subject(s)
Hemolymph/immunology , Hemolysin Proteins/isolation & purification , Lepidoptera/immunology , Moths/immunology , Animals , Bacterial Vaccines , Electrophoresis, Polyacrylamide Gel , Hemolysin Proteins/analysis , Hemolytic Plaque Technique , Phospholipases A/analysis , Pseudomonas aeruginosa/immunology , Time Factors , Type C Phospholipases/analysis , Vaccination
18.
Clin Chim Acta ; 99(3): 279-82, 1979 Dec 17.
Article in English | MEDLINE | ID: mdl-519865

ABSTRACT

The application of equilibrium dialysis to the determination of the "free", i.e. non-albumin bound fraction of human plasma or serum tryptophan has been re-examined. A potentially serious error in the application of this method is outlined and the necessary correction and some precautionary measures are discussed.


Subject(s)
Tryptophan/blood , Dialysis/methods , Evaluation Studies as Topic , Humans
19.
Vet Immunol Immunopathol ; 19(3-4): 251-8, 1988 Oct.
Article in English | MEDLINE | ID: mdl-3252617

ABSTRACT

A simple multicomponent isolation procedure for bovine C3, factor B, factor D and conglutinin (K) from a single serum sample is described. The components of the alternative pathway C3 convertase were isolated in milligram quantities from 800 ml bovine serum and were found to be functionally pure with respect to each other and to factors H and I.


Subject(s)
Cattle/immunology , Collectins , Complement Activating Enzymes/isolation & purification , Complement Activation , Complement C3-C5 Convertases/isolation & purification , Complement Pathway, Alternative , Animals , Chromatography , Complement C3/isolation & purification , Complement Factor B/isolation & purification , Complement Factor D/isolation & purification , Complement Fixation Tests , Serum Globulins/isolation & purification
20.
Radiat Prot Dosimetry ; 95(4): 295-308, 2001.
Article in English | MEDLINE | ID: mdl-11707028

ABSTRACT

Data on the gastrointestinal absorption of 12 elements have been reviewed. In each case, absorption is expressed as the fraction of the ingested element absorbed to blood, referred to as the f1 value, applying to intakes of unspecified chemical form by average population groups. The level of confidence in individual absorption values has been estimated in terms of lower and upper bounds, A and B, such that there is judged to be roughly a 90% probability that the true central value is no less than A and no greater than B. Ranges are proposed for intakes by adults, 10-year-old children and 3-month-old infants. Uncertainty in f1 values (B/A) ranged from 10% to factors of 100-400. The lowest uncertainties were for the well absorbed elements, H, I and Cs, for which there are good data, and the greatest uncertainties were for less well absorbed elements for which few data are available, particularly Zr and Sb. Ranges were generally wider for children and infants than for adults because of the need to allow for the likelihood of increased absorption with only limited data in support of the proposed values. The largest ranges were for 3-month-old infants, reflective lack of knowledge on the time-course and magnitude of possible increased absorption in the first few months of life. For each age group, ICRP values of absorption tend towards the upper bound of the ranges, indicating a degree of conservatism in th calculation of ingestion dose coefficients. Examination of the effect of the proposed confidence intervals for f1 values on uncertainties in dose coefficients for ingested radionuclides showed that there was no direct relationship. For some radionuclides, uncertainties in effective dose were small despite large uncertainties in f1 values while for others the uncertainties in effective doses approached the corresponding values for uncertainty in f1 values. These differences reflect the relative contributions to effective dose from cumulative activity in the contents of the alimentary tract, which in many cases is insensitive to uncertainties in f1, and cumulative activity of the absorbed radionuclide in systemic tissues, which is proportional to f1. In general, uncertainties in effective close for children and infants exceeded those in adults as a result of greater uncertainties in f1 values for the younger age groups. However, this effect was reduced in some cases by shorter retention times of absorbed nuclides in body tissues and organs.


Subject(s)
Elements , Intestinal Absorption/radiation effects , Radioisotopes/pharmacokinetics , Adult , Child , Dose-Response Relationship, Radiation , Humans , Infant , Radiation Dosage , Radiation Protection , Tissue Distribution
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