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1.
J Fish Biol ; 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38226528

ABSTRACT

Acoustic telemetry has seen a rapid increase in utility and sophistication in recent years and is now used extensively to assess the behavior and survival rates of many aquatic animals, including the Atlantic salmon. As part of the salmon's complex life cycle, salmon smolts are thought to make a unidirectional migration from fresh water to the sea, which is initiated by changes in their physiology. However, some tag movement patterns do not conform with this and can be difficult to explain, particularly if the tagged fish has been eaten by a predator. This study combines the use of predator tags with machine learning techniques to understand the fate of migrating salmon smolts and thereby improve estimates for migration success. Over 3 years between 2020 and 2022, 217 salmon smolts (including wild and hatchery-reared ranched fish) were acoustically tagged and released into an embayment on the west coast of Ireland. Some tagged smolts were observed to return from the estuary back into a saline lagoon through which they had already migrated. To distinguish between the movement of a salmon smolt and that of a predator, predator tags were deployed in migrating smolts in 2021 and 2022. The addition of a temperature sensor in 2022 enabled the determination of predator type causing the returning movement. A significant number of predator tags were triggered, and the patterns of movement associated with these triggered tags were then used with two types of machine learning algorithms (hierarchical cluster analysis and random forest) to identify and validate the behavior of smolts tagged without extra sensors. Both models produced the same outputs, grouping smolts tagged with predator tags with smolts tagged without the additional sensors but showing similar movements. A mammalian predator was identified as the cause of most reversal movement, and hatchery-reared ranched smolts were found to be more likely predated upon by this predator than wild smolts within the lake and the estuary. However, overall migration success estimates were similar for both wild and hatchery-reared ranched fish. This study highlights the value of predator tags as an essential tool in the overall validation of detection data.

2.
J Child Adolesc Trauma ; 16(1): 43-53, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36776629

ABSTRACT

Background: Awareness of adverse childhood experiences and their impact on adult psychopathology primarily focuses on adversities within the home. There is limited insight into the impact of adversities across peer environments. Objective: This study investigates 19 items related to adverse experiences across the home, school and peer environments and their relationship to 12-month and lifetime psychopathology. Data: Secondary analysis of the Ulster University Student Well-being Study. The dataset included completed responses across all selected variables for 729 participants. Method and Results: Latent profile analysis identified a low adversity profile, bullying adversity profile and higher prevalence adversity profile. Regression analysis of the three profiles and demographics variables indicated their impact on adult psychopathology lifetime and 12-month prevalence rates. Conclusion: Schools and HE institutions should acknowledge the impact of childhood adversities. In doing so, it is important to consider the deeper impact of bullying due to its links with psychopathology across the lifespan. Educational institutions should take appropriate steps to mitigate continued exposure as students' progress through the education system.

3.
J Fish Biol ; 92(5): 1404-1421, 2018 May.
Article in English | MEDLINE | ID: mdl-29607514

ABSTRACT

A total of 12 adult European sea bass Dicentrarchus labrax were tagged with pop-off satellite archival tags (PSAT) in Irish coastal waters and in offshore waters in the north-east Celtic Sea between 2015 and 2016. Archived data were successfully recovered from five of the 12 tags deployed, three from fish released in inshore Irish waters and two from fish released offshore in the eastern Celtic Sea. All three fish tagged in inshore waters were found to undertake migrations into the open ocean coinciding with the spawning period. These fish also exhibited fidelity to inshore sites post-migration, returning to the same general location (within c. 73 km, which is roughly the predicted mean accuracy of the method) of their original release site. Although the number of tracks obtained here was limited, some degree of aggregation between inshore and offshore tagged fish in the eastern Celtic Sea was noted during the expected spawning period suggesting PSATs can provide new information on specific spawning locations of European sea bass.


Subject(s)
Animal Migration , Bass , Satellite Communications , Animals , Atlantic Ocean , Ireland , Sexual Behavior, Animal , Temperature
4.
Environ Monit Assess ; 189(6): 303, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28567597

ABSTRACT

Agricultural pesticides are widely used in Suriname, an upper middle-income Caribbean country located in South America. Suriname imported 1.8 million kg of agricultural pesticides in 2015. So far, however, national monitoring of pesticides in crops is absent. Reports from the Netherlands on imported Surinamese produce from 2010 to 2015 consistently showed that samples exceeded plant-specific pesticide maximum residue limits (MRLs) of the European Union (EU). Consumption of produce containing unsafe levels of pesticide residues can cause neurological disorders, and particularly, pregnant women and children may be vulnerable. This pilot study assessed the presence of pesticide residues in commonly consumed produce items cultivated in Suriname. Thirty-two insecticides (organophosphates, organochlorines, carbamates, and pyrethroids) and 12 fungicides were evaluated for their levels in nine types of produce. Pesticide residue levels exceeding MRLs in this study regarded cypermethrin (0.32 µg/g) in tomatoes (USA MRL 0.20 µg/g), lambda-cyhalothrin (1.08 µg/g) in Chinese cabbage (USA MRL 0.40 µg/g), endosulfan (0.07 µg/g) in tannia (EU MRL 0.05 µg/g), and lindane (0.02 and 0.03 µg/g, respectively) in tannia (EU MRL 0.01 µg/g). While only a few pesticide residues were detected in this small pilot study, these residues included two widely banned pesticides (endosulfan and lindane). There is a need to address environmental policy gaps. A more comprehensive sampling and analysis of produce from Suriname is warranted to better understand the scope of the problem. Preliminary assessments, using intake rate, hazard quotient, and level of concern showed that it is unlikely that daily consumption of tannia leads to adverse health effects.


Subject(s)
Environmental Monitoring , Pesticide Residues/analysis , Vegetables/chemistry , Agriculture , Carbamates/analysis , Crops, Agricultural/chemistry , Endosulfan/analysis , Food Contamination/analysis , Food Contamination/statistics & numerical data , Fungicides, Industrial/analysis , Hexachlorocyclohexane/analysis , Humans , Hydrocarbons, Chlorinated/analysis , Insecticides/analysis , Nitriles/analysis , Pesticides/analysis , Pilot Projects , Pyrethrins/analysis , Suriname
5.
Biotechnol Bioeng ; 114(9): 1970-1977, 2017 09.
Article in English | MEDLINE | ID: mdl-28369727

ABSTRACT

Monoclonal antibodies (mAbs) contain short N-terminal signal peptides on each individual polypeptide that comprises the mature antibody, targeting them for export from the cell in which they are produced. The signal peptide is cleaved from each heavy chain (Hc) and light chain (Lc) polypeptide after translocation to the ER and prior to secretion. This process is generally highly efficient, producing a high proportion of correctly cleaved Hc and Lc polypeptides. However, mis-cleavage of the signal peptide can occur, resulting in truncation or elongation at the N-terminus of the Hc or Lc. This is undesirable for antibody manufacturing as it can impact efficacy and can result in product heterogeneity. Here, we describe a truncated variant of the Lc that was detected during a routine developability assessment of the recombinant human IgG1 MEDI8490 in Chinese hamster ovary cells. We found that the truncation of the Lc was caused due to the use of the murine Hc signal peptide together with a lambda Lc containing an SYE amino acid motif at the N-terminus. This truncation was not caused by mis-processing of the mRNA encoding the Lc and was not dependent on expression platform (transient or stable), the scale of the fed-batch culture or clonal lineage. We further show that using alternative signal peptides or engineering the Lc SYE N-terminal motif prevented the truncation and that this strategy will improve Lc homogeneity of other SYE lambda Lc-containing mAbs. Biotechnol. Bioeng. 2017;114: 1970-1977. © 2017 Wiley Periodicals, Inc.


Subject(s)
Antibodies, Monoclonal/genetics , Immunoglobulin Light Chains/genetics , Protein Engineering/methods , Protein Sorting Signals/genetics , Amino Acid Sequence/genetics , Animals , CHO Cells , Cricetulus , Humans , Molecular Sequence Data , Structure-Activity Relationship
6.
J Evol Biol ; 23(12): 2718-25, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20964785

ABSTRACT

Visual signals play a vital role in many animal communication systems. Signal design, however, often varies within species, raising evolutionarily important questions concerning the maintenance of phenotypic diversity. We analysed nuptial colour variation within and among nine populations of southern pygmy perch (Nannoperca australis Günther) along an environmental light gradient. Within populations, larger males were redder and blacker, and better-condition males were blacker. Among populations, red colour was positively correlated with the amount of orange-red light present, suggesting that males are likely optimizing signal conspicuousness by producing proportionally larger and redder patches in broad spectrum environments with more orange-red light. Signal contrast, in this regard, is maximized when red colour, appearing bright because of the prevalence of red wavelengths, is viewed against the water-column background. Together, our results are concordant with the sensory drive hypothesis; selection favours signal adaptations or signal plasticity to ensure communication efficacy is maximized in different light environments.


Subject(s)
Animal Communication , Color , Perches/anatomy & histology , Animals , Female , Male , Mating Preference, Animal , Perches/genetics , Perches/physiology , Selection, Genetic
7.
Microbiology (Reading) ; 155(Pt 3): 687-698, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19246740

ABSTRACT

Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen that causes acute and chronic infections in immunocompromised individuals. It is also a model organism for bacterial biofilm formation. Acute infections are often associated with planktonic or free-floating cells, high virulence and fast growth. Conversely, chronic infections are often associated with the biofilm mode of growth, low virulence and slow growth that resembles that of planktonic cells in stationary phase. Biofilm formation and type III secretion have been shown to be reciprocally regulated, and it has been suggested that factors related to acute infection may be incompatible with biofilm formation. In a previous proteomic study of the interrelationships between planktonic cells, colonies and continuously grown biofilms, we showed that biofilms under the growth conditions applied are more similar to planktonic cells in exponential phase than to those in stationary phase. In the current study, we investigated how these conditions influence the production of virulence factors using a transcriptomic approach. Our results show that biofilms express the type III secretion system, whereas planktonic cells do not. This was confirmed by the detection of PcrV in the cellular and secreted fractions of biofilms, but not in those of planktonic cells. We also detected the type III effector proteins ExoS and ExoT in the biofilm effluent, but not in the supernatants of planktonic cells. Biofilm formation and type III secretion are therefore not mutually exclusive in P. aeruginosa, and biofilms could play a more active role in virulence than previously thought.


Subject(s)
Biofilms/growth & development , Pseudomonas aeruginosa/growth & development , Pseudomonas aeruginosa/metabolism , Virulence Factors/biosynthesis , Bacterial Proteins/metabolism , Gene Expression Profiling , Gene Expression Regulation, Bacterial , Oligonucleotide Array Sequence Analysis , Pseudomonas aeruginosa/genetics , RNA, Bacterial/metabolism
8.
J Qual Clin Pract ; 20(2-3): 101-6, 2000.
Article in English | MEDLINE | ID: mdl-11057992

ABSTRACT

Perth Clinic is a 35-bed private psychiatric clinic. In February 1999 an adolescent and young adult therapy service was introduced in response to an increasing number of enquiries regarding the treatment of adolescent and young adults with psychiatric disorders. This program was developed by a working party of mental health professionals including psychiatrists, clinical psychologists, nurses and occupational therapists. The program design described the type of program to be delivered, its content and structure, and the method of evaluation. In consultation with similar services around the world, Perth Clinic developed two therapy streams for this population. The first is an inpatient program based on an open group format of 4 1/2 hours of therapy daily. The second is a closed group program conducted for two 3 hour sessions per week. Groups are held in the late afternoon (16.00-19.00 h) for an 8 week period. Both streams have a maximum of eight participants and all participants are referred by a psychiatrist. Outcomes are measured by a battery of clinical questionnaires which provide objective measurement of mood changes. Patient and parent satisfaction with the program is also measured. Indicators at this early stage are that this is an effective intervention program with high rates of attendance and good prognostic data. This study describes the first 6 months of this program's operation.


Subject(s)
Mental Disorders/therapy , Mental Health Services , Adolescent , Adolescent Medicine , Adult , Cognitive Behavioral Therapy , Hospitals, Psychiatric , Humans , Patient Satisfaction , Prognosis , Program Evaluation , Quality of Health Care , Surveys and Questionnaires , Western Australia
9.
Vaccine ; 18(5-6): 531-9, 1999 Oct 14.
Article in English | MEDLINE | ID: mdl-10519944

ABSTRACT

The safety and immunogenicity of 2 yeast-derived, blood-stage malaria vaccines were evaluated in a phase l trial. Healthy adults were given 2 or 3 doses of alum-adsorbed vaccine containing the 19 kDa carboxy-terminal fragment of the merozoite surface protein-1 (MSP-1(19)) derived from the 3D7 or the FVO strain of Plasmodium falciparum fused to tetanus toxoid T-helper epitopes P30 and P2. The first 2 doses of MSP-1(19) were well tolerated. Hypersensitivity reactions occurred in 3 subjects after the third dose of MSP-1(19), including bilateral injection site reactions in 2 (one with generalized skin rash), and probable histamine-associated hypotension in 1. Serum antibody responses to MSP-1(19) occurred in 5/16, 9/16 and 0/8 subjects given 20 microg of MSP-1(19), 200 microg of MSP-1(19), and control vaccines (hepatitis B or Td), respectively. Both MSP-1(19) vaccines were immunogenic in humans, but changes in formulation will be necessary to improve safety and immunogenicity profiles.


Subject(s)
Epitopes, T-Lymphocyte , Malaria Vaccines/immunology , Merozoite Surface Protein 1/immunology , Peptide Fragments/immunology , Plasmodium falciparum/immunology , T-Lymphocytes, Helper-Inducer/immunology , Tetanus Toxoid/immunology , Vaccines, Synthetic/immunology , Adolescent , Adult , Animals , Antibodies, Protozoan/blood , Humans , Lymphocyte Activation , Malaria Vaccines/adverse effects , Middle Aged , Skin Tests
10.
Alcohol ; 19(1): 75-84, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10487391

ABSTRACT

Prolonged alcohol consumption is associated with a variety of neuropsychiatric conditions, including the dense amnesic disorder known as Korsakoff's syndrome. Korsakoff's syndrome is frequently diagnosed in alcoholics after an episode of acute thiamin deficiency. The accepted view within the medical literature is that the etiology of this disorder lies in thiamin deficiency or Wernicke's encephalopathy. However, examination of the published reports of pure thiamin deficiency unaccompanied by chronic and excessive consumption of alcohol shows that, in this group of patients, the rate of progression to Korsakoff's syndrome is low. This result suggests that the memory impairments associated with alcohol-related brain damage cannot be attributed to thiamin deficiency alone. The etiology of alcohol-related cognitive impairments such as Korsakoff's syndrome is still poorly understood but several lines of evidence suggest multiple causal factors interact to produce deficits in performance. Animal models that manipulate only a single putative etiological factor are unlikely to elucidate the multiple influences that lead to Korsakoff's syndrome. A study of the natural history of alcohol-related brain damage is needed that will allow an assessment of individual risk factors and their interactions.


Subject(s)
Alcoholism/complications , Korsakoff Syndrome/etiology , Thiamine Deficiency/complications , Wernicke Encephalopathy/etiology , Animals , Disease Models, Animal , Humans , Memory Disorders/etiology , Wernicke Encephalopathy/diagnosis
11.
Chem Senses ; 23(3): 359-62, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9669049

ABSTRACT

An olfactory stimulus and a visual stimulus were employed in a context-dependent memory study using a prose passage as the to-be-remembered item. Ninety-five university students (aged 17-35 years) learned the passage of prose in the presence of one of the stimuli and were then asked to recall the passage with the original context either reinstated or not reinstated. The results revealed a significant context-dependent memory effect for the olfactory cue but not for the visual cue. They demonstrate support for the effectiveness of odours as context cues and it is suggested that context-dependent memory processes may underlie the formation and retrieval of odour-evoked autobiographical memories.


Subject(s)
Color , Memory/physiology , Odorants , Adolescent , Adult , Female , Humans , Male , Mental Recall
12.
Alcohol ; 14(1): 81-91, 1997.
Article in English | MEDLINE | ID: mdl-9014028

ABSTRACT

The underlying pathogenesis of Korsakoff's syndrome, an amnesic disorder most commonly found in alcoholics, is not well understood. Chronic alcoholism is associated with thiamin deficiency and current thinking is that this may be the causal factor. In Experiment 1, rats were given a 20% (v/v) ethanol/water mix as their only source of fluid for 156 days. Three groups were made thiamin deficient through the combination of a thiamin-deficient diet and the centrally acting thiamin antagonist pyrithiamin hydrobromide, after 4, 15, and 26 weeks exposure to ethanol, respectively. The control group was given ad lib access to laboratory chow and water throughout this period. There were no differences between groups on either the working or reference versions of the Morris water tank paradigm. In Experiment 2, to test the hypothesis that a single bout of thiamin deficiency, with or without concurrent alcohol intake, is not sufficient to cause severe memory impairments, two groups of rats were subjected to three bouts of thiamin deficiency. One of these groups consumed an ethanol/water mix, the other tap water. A third group was made thiamin deficient on only one occasion. The control group was not made thiamin deficient and consumed lab chow and tap water throughout. Once again, there were no between-group differences in the data derived from testing in either the eight-arm radial maze or the Morris water tank task. These experiments indicate that the aetiology of Korsakoff's syndrome is more complex than previously thought.


Subject(s)
Alcohol Drinking/psychology , Memory/physiology , Thiamine Deficiency/psychology , Animals , Body Weight/drug effects , Diet , Male , Maze Learning/drug effects , Rats , Rats, Wistar
13.
Behav Brain Res ; 80(1-2): 27-32, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8905125

ABSTRACT

Exposure to non-contingent food delivery has been shown to elicit an increase in nociceptive thresholds in rats. This hypoalgesia has previously been shown to be reversible by the opiate antagonist naloxone. Given that most opioid forms of SIA are found to rely on an intact pituitary-adrenal axis, this research examined the possibility that the hypoalgesic response to non-contingent food delivery is also hormonally mediated. Hypophysectomy (Expt. 1) but not bilateral adrenalectomy (Expt. 2) was found to completely attenuate the hypoalgesic response to non-contingent food delivery. Preliminary data from ongoing research is presented that points to the possible involvement of the hypophyseal peptides beta-endorphin and adrenocorticotropin hormone (ACTH).


Subject(s)
Pain Threshold/physiology , Pituitary-Adrenal System/physiology , Stress, Psychological/physiopathology , Adrenalectomy , Adrenocorticotropic Hormone/metabolism , Animals , Food , Hypophysectomy , Male , Pain Measurement , Pituitary Gland, Posterior/metabolism , Rats , Rats, Wistar , Reaction Time/physiology , beta-Endorphin/metabolism
14.
Psychophysiology ; 33(4): 416-25, 1996 Jul.
Article in English | MEDLINE | ID: mdl-8753942

ABSTRACT

Two experiments examined the effects of facial expressions of emotion as conditioned stimuli (CSs) on human electrodermal conditioning and on a continuous measure of expectancy of the shock unconditioned stimulus. In Experiment 1, the CS+ was a picture of a person displaying an angry face and CS- was a neutral face. For half of the subjects, the expressions were depicted by males, for the other half by females. Male subjects showed larger skin conductance responses to pictures of males than did females. The responding of female subjects was the same regardless of the sex of the person in the picture. In Experiment 2, the CS+ and CS- were pictures of an angry or a happy face. For half of the subjects, the expressions were depicted by adult males, for the other half by preadolescent males. Subjects displayed greater differentiation when an adult male depicting anger was employed as the CS+ than when a preadolescent male depicting anger was the CS+. There were no differences when an adult or a child displayed happiness.


Subject(s)
Conditioning, Classical/physiology , Emotions/physiology , Facial Expression , Adolescent , Adult , Aging/psychology , Female , Galvanic Skin Response/physiology , Humans , Male , Sex Characteristics
15.
Behav Brain Res ; 65(2): 147-52, 1994 Dec 15.
Article in English | MEDLINE | ID: mdl-7718146

ABSTRACT

Exposure to non-contingent food delivery has been shown to elicit an increase in nociceptive thresholds in rats. The conditions which elicit analgesia are similar to those that elicit schedule-induced polydipsia. In both instances animals are food-deprived and receive food on an intermittent schedule. Interpellet interval has been found to be an important predictor of schedule-induced polydipsia. Experiment 1 therefore investigated the effect of varying the interval between pellet deliveries on tail flick latencies in rats. The relationship between nociceptive threshold and inter-pellet interval was found to be bitonic in nature given that animals submitted to fixed time schedules of 30 or 60 s, but not 15 or 120 s, exhibited significant increases in tail flick latencies. Experiment 2 examined the effect of providing animals with water during exposure to non-contingent food delivery. Under these conditions animals exhibited polydipsic behaviour, the development of which attenuated the hypoalgesic response to non-contingent food delivery.


Subject(s)
Drinking Behavior/physiology , Pain/psychology , Animals , Food , Male , Nociceptors/physiology , Pain Measurement , Pain Threshold/physiology , Rats , Rats, Wistar , Reinforcement Schedule , Time Factors
17.
Pediatr Nurs ; 20(2): 123-30, 1994.
Article in English | MEDLINE | ID: mdl-8159498

ABSTRACT

The philosophy of family-centered care recognizes parents as equal in partnerships with professionals. An adapted nursing process can provide a useful mechanism for members of this partnership to create and maintain a system that promotes an optimal quality of life at home for children who are technology dependent and their families. A family-centered assessment requires the nurse to facilitate the family's self-assessment and promote a family systems perspective. The family and the nurse together develop a plan of care, with the family establishing priorities. The nurse assumes joint responsibility with the family in implementing the plan of care, and promotes the principle of normalization and the use of informal options whenever possible. Evaluation is formal, informal, and ongoing and includes the family and nurse's evaluation of both outcome and process.


Subject(s)
Family , Home Care Services , Nursing Process , Technology , Adult , Child, Preschool , Education, Nursing, Continuing , Female , Humans , Infant , Male , Parents/education , Patient Care Team , Patient Discharge
18.
Vaccine ; 12(3): 195-9, 1994.
Article in English | MEDLINE | ID: mdl-8165850

ABSTRACT

Clinical and serum antibody responses following intramuscular injection of two formulations of Salmonella typhi Vi capsular polysaccharide (Vi) were assessed in a double-blind evaluation. Healthy adults were randomly assigned to receive a 25 micrograms dose of liquid (Vi-Liq; n = 182) or freeze-dried Vi vaccine (Vi-Lyoph; n = 55), or placebo (n = 86). Erythema and/or induration > or = 1 cm in diameter at the injection site developed in 13/182 (7%) of Vi-Liq and 3/55 (5%) of Vi-Lyoph recipients (not significant, n.s.). Fever (oral temperature > or = 100 degrees F (37.8 degrees C)) occurred in < 2% of vaccinees. The frequencies of rises of fourfold or greater and of maximal Vi antibody levels were similar in the two vaccine groups. Fourfold or greater rises in serum Vi antibody levels (RIA) developed in 53% of Vi-Lyoph and 60% of Vi-Liq recipients by 1 week (n.s.), and 98 and 93%, respectively, by 1 month (n.s.). The frequencies of adverse reactions and mean Vi antibody levels following booster immunization with Vi-Liq 27 to 34 months after primary immunization (n = 55) were similar to those observed following primary immunization, although subjects given a booster dose were more likely to develop local reactions > or = 1 cm in diameter than those given a first dose (10/55 versus 13/182, p = 0.013 by the chi 2 test). Primary and booster immunizations with the Vi vaccines are well tolerated in healthy adults; mean Vi antibody levels remain significantly elevated for up to 34 months after primary immunization.


Subject(s)
Antibodies, Bacterial/blood , Polysaccharides, Bacterial/administration & dosage , Typhoid Fever/prevention & control , Typhoid-Paratyphoid Vaccines/administration & dosage , Adolescent , Adult , Antibodies, Bacterial/biosynthesis , Double-Blind Method , Freeze Drying , Humans , Immunization, Secondary , Polysaccharides, Bacterial/adverse effects , Polysaccharides, Bacterial/immunology , Typhoid Fever/immunology , Typhoid-Paratyphoid Vaccines/adverse effects , Typhoid-Paratyphoid Vaccines/immunology , Vaccination
19.
J Exp Psychol Gen ; 122(4): 449-61, 1993 Dec.
Article in English | MEDLINE | ID: mdl-8263464

ABSTRACT

Human conditioning research has revealed an apparent resistance to extinction of aversive conditioning to pictures of fear-relevant stimuli such as snakes and spiders, supporting M. E. P. Seligman's (1971) preparedness theory of fears and phobias. This article examines an alternative account based on activation of preexisting response tendencies under threat (selective sensitization). Two experiments demonstrate that selective sensitization of electrodermal responses is attenuated when a fear-relevant stimulus serves as a negative conditioned stimulus (CS-), but is maintained when it serves as a positive conditioned stimulus (CS+). Previous extinction results may therefore be due to preservation of initial responding to CS+ but not CS-. Selective sensitization offers a model for the nonassociative activation of fears and phobias to prepotent stimuli under conditions of stress or threat. Possible genetic and cognitive mechanisms are discussed.


Subject(s)
Phobic Disorders/genetics , Repression-Sensitization , Acoustic Stimulation , Adult , Cognition , Conditioning, Classical , Electric Stimulation , Electrodes , Female , Galvanic Skin Response , Humans , Male , Photic Stimulation , Reinforcement, Psychology
20.
Vaccine ; 11(9): 909-13, 1993.
Article in English | MEDLINE | ID: mdl-8212835

ABSTRACT

The safety of licensed influenza virus vaccine (IVV) combined with a novel adjuvant containing muramyl tripeptide (MTP) conjugated to phosphatidylethanolamine (PE) was evaluated in a randomized pilot study. Ten healthy 23-30-year-old men were given a single intramuscular dose of IVV combined with saline (n = 5) or with 100 micrograms of MTP-PE in the MF59 adjuvant emulsion (MF59-100) (n = 5). Evaluations were performed on days 0, 1, 2, 4, 7 and 28 after inoculation. IVV alone was well tolerated. All volunteers immunized with IVV/MF59-100 experienced moderate to severe local and systemic reactions which interfered with usual activities. Discomfort at the injection site was first noted at 2-6 h; induration (5/5), erythema (3/5), and regional adenopathy (3/5) persisted for up to 4 days. Systemic symptoms including chills (5/5), fever (3/5), nausea (3/5) and/or dizziness (2/5) developed within 12 h of inoculation and resolved by 48 h. Elevated white blood cell count (days 1 and 2), erythrocyte sedimentation rate and serum fibrinogen were transiently observed. Although peak serum neutralizing antibody titres versus influenza A/H3N2 and influenza B antigens were higher in the group given IVV with MF59-100, these unexpected reactions indicate that this dose of adjuvant is unsuitable for use in combination with this IVV.


Subject(s)
Acetylmuramyl-Alanyl-Isoglutamine/analogs & derivatives , Adjuvants, Immunologic , Antibodies, Viral/biosynthesis , Influenza A virus/immunology , Influenza B virus/immunology , Influenza Vaccines , Phosphatidylethanolamines , Acetylmuramyl-Alanyl-Isoglutamine/administration & dosage , Acetylmuramyl-Alanyl-Isoglutamine/adverse effects , Acetylmuramyl-Alanyl-Isoglutamine/immunology , Adjuvants, Immunologic/administration & dosage , Adjuvants, Immunologic/adverse effects , Adult , Animals , Dizziness/etiology , Emulsions/administration & dosage , Emulsions/adverse effects , Endotoxins/adverse effects , Endotoxins/analysis , Erythema/etiology , Fatigue/etiology , Fever/chemically induced , Humans , Influenza Vaccines/administration & dosage , Influenza Vaccines/adverse effects , Influenza Vaccines/immunology , Injections, Intramuscular , Male , Nausea/etiology , Neutralization Tests , Pain/etiology , Phosphatidylethanolamines/administration & dosage , Phosphatidylethanolamines/adverse effects , Phosphatidylethanolamines/immunology , Pilot Projects , Rabbits , Safety , Vaccines, Inactivated/administration & dosage , Vaccines, Inactivated/adverse effects , Vaccines, Inactivated/immunology
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