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Biomedical subjects

K Cameron

Publications and source records attributed to K Cameron.

At least 19 recordsLinked to original sources

Antigenic and genetic diversity among swine influenza A H1N1 and H1N2 viruses in Europe.

Three subtypes of influenza A viruses, H1N1, H1N2 and H3N2, co-evolve in pigs in Europe. H1N2 viruses isolated from pigs in France and Italy since 1997 were closely related to the H1N2 viruses which emerged in the UK in 1994. In particular, the close relationship of the neuraminidases (NAs) of these viruses to the NA of a previous UK H3N2 swine virus indicated that they had not acquired the NA from H3N2 swine viruses circulating in continental Europe. Moreover, antigenic and genetic heterogeneity among the H1N2 viruses appeared to be due in part to multiple introductions of viruses from the UK. On the other hand, comparisons of internal gene sequences indicated genetic exchange between the H1N2 viruses and co-circulating H1N1 and/or H3N2 subtypes. Most genes of the earlier (1997-1998) H1N2 isolates were more closely related to those of a contemporary French H1N1 isolate, whereas the genes of later (1999-2000) isolates, including the HAs of some H1N2 viruses, were closely related to those of a distinct H1N1 antigenic variant which emerged in France in 1999. In contrast, an H3N2 virus isolated in France in 1999 was closely related antigenically and genetically to contemporary human A/Sydney/5/97-like viruses. These studies reveal interesting parallels between genetic and antigenic drift of H1N1 viruses in pig and human populations, and provide further examples of the contribution of genetic reassortment to the antigenic and genetic diversity of swine influenza viruses and the importance of the complement of internal genes in the evolution of epizootic strains.

Animals↗

Measurement of the rate of nu(e) + d --> p + p + e(-) interactions produced by (8)B solar neutrinos at the Sudbury Neutrino Observatory.

Solar neutrinos from (8)B decay have been detected at the Sudbury Neutrino Observatory via the charged current (CC) reaction on deuterium and the elastic scattering (ES) of electrons. The flux of nu(e)'s is measured by the CC reaction rate to be straight phi(CC)(nu(e)) = 1.75 +/- 0.07(stat)(+0.12)(-0.11)(syst) +/- 0.05(theor) x 10(6) cm(-2) s(-1). Comparison of straight phi(CC)(nu(e)) to the Super-Kamiokande Collaboration's precision value of the flux inferred from the ES reaction yields a 3.3 sigma difference, assuming the systematic uncertainties are normally distributed, providing evidence of an active non- nu(e) component in the solar flux. The total flux of active 8B neutrinos is determined to be 5.44+/-0.99 x 10(6) cm(-2) s(-1).

Journal Article↗

Antigens to viral capsid and non-capsid proteins are present in brain tissues and antibodies in sera of Theiler's virus-infected mice.

Recombinant proteins to the LP, VP1, VP2, VP3, VP4, 2A, 2B, 2C, 3A, and 3D genes of Theiler's murine encephalomyelitis virus (TMEV) were generated and antibodies were produced against them for use in analysis of the TMEV epitopes responsible for eliciting the antibody responses observed during acute and chronic disease. Antibodies against recombinant VP1, VP2, and VP3 recognized the corresponding proteins from purified TMEV particles. In immunohistochemical analysis, antibodies against recombinant capsid (VP1, VP2, and VP3), and non-capsid (2A, 2C, 3A) proteins were reactive with PO-2D cells (astrocytes) infected with TMEV in vitro and with brain tissues of acutely infected mice. Antibodies against VP4, 2B, and 3D antigens were not reactive with corresponding viral proteins in infected astrocytes cells or brain tissues, but they reacted with TMEV precursor proteins produced during the early viral replication phase. Sera from SJL/J mice infected with TMEV acutely (14 days) and chronically (45 days) reacted with VP1, VP2, VP4, 2A, and 2C proteins. In an in vitro assay for neutralization, only anti-VP1 antibodies neutralized TMEV infection. These findings suggest that both capsid and non-capsid proteins of TMEV play a role in the immunopathology of the TMEV disease in the central nervous system.

Animals↗

Infection of a child in Hong Kong by an influenza A H3N2 virus closely related to viruses circulating in European pigs.

Influenza virus A/Hong Kong/1774/99, isolated from a young child with mild influenza, was shown to be similar in its antigenic and genetic characteristics to H3N2 viruses circulating in pigs in Europe during the 1990s and in particular to be closely related to viruses isolated from two children in the Netherlands in 1993. Similar viruses had previously not been identified outside Europe. Although there is little evidence as to how the child contracted the infection, it appears likely that pigs in southern China were the source of infection. Characteristics shared with the European swine viruses include resistance to the anti-influenza drugs amantadine and rimantadine. Thus not only does this incident once again highlight the potential of pigs as a source of novel human influenza viruses, but also indicates the potential for emergence of amantadine-resistant human viruses.

Amantadine↗

Green, Mandel, Hotvedt, Gray, and Smith's study of 50 lesbian mothers and their children: inconsistencies in four published reports of the data.

The 1986 study of 50 lesbian mothers by Green, et al. may be the most influential concerning homosexual parenting. However, after setting standards for--and noting preliminary evidence of--gender identity confusion in 1980 and 1982, confirmatory findings in 1986 were not included in the report's abstract and conclusions. Numerous discrepancies in different published accounts of this study--including number of subjects and how, subjects were matched and analyzed--cannot be reconciled. The earliest reports were not cited in the final report which led to treatment in the literature as separate studies. The inconsistencies between the published accounts are substantive and numerous enough to recommend that the authors issue a complete and detailed report of the study.

Adult↗

Avian-to-human transmission of H9N2 subtype influenza A viruses: relationship between H9N2 and H5N1 human isolates.

In 1997, 18 cases of influenza in Hong Kong (bird flu) caused by a novel H5N1 (chicken) virus resulted in the deaths of six individuals and once again raised the specter of a potentially devastating influenza pandemic. Slaughter of the poultry in the live bird markets removed the source of infection and no further human cases of H5N1 infection have occurred. In March 1999, however, a new pandemic threat appeared when influenza A H9N2 viruses infected two children in Hong Kong. These two virus isolates are similar to an H9N2 virus isolated from a quail in Hong Kong in late 1997. Although differing in their surface hemagglutinin and neuraminidase components, a notable feature of these H9N2 viruses is that the six genes encoding the internal components of the virus are similar to those of the 1997 H5N1 human and avian isolates. This common feature emphasizes the apparent propensity of avian viruses with this genetic complement to infect humans and highlights the potential for the emergence of a novel human pathogen.

Animals↗

Nutritional status of an adult cystic fibrosis population.

Nutritional management and dietary recommendations in patients with cystic fibrosis (CF) have changed considerably over the past 10-15 y. The nutritional status of adult CF patients was assessed in a clinical survey before these changes in nutritional management. The aim of the study was to assess the current nutritional status of the CF population and compare the results with those of the previous study. Forty-three (24 male, 19 female) subjects participated in this study. Subjects' height, weight, mid-upper-arm circumference, and skinfolds at four sites were measured. Nutritional intake was measured by using a 7-d food intake diary including documentation of supplements taken. Compared with the 1983 study, the incidence of malnutrition, as indicated by a body mass index of less than 20, has decreased from 62% to 9%. Furthermore, there have been significant improvements in the weight, height, and body mass index of both males (P < 0.001) and females (P < 0.04). Individuals with CF are no longer subject to growth arrest, as their mean height is now comparable to the Australian average. Mid-upper-arm circumference (P < 0.0001), triceps skinfold (P < 0.0001), and percentage of body fat (P < 0.05) of males and females have also significantly increased. The fat intake (P < 0.02) of females and males and energy intake (P < 0.03) of females have increased significantly, and the mean energy intake of subjects has exceeded the recommended 120% of the recommended daily intake. A significant number of patients in the present study receive dietary oral and/or enteral supplements. Multiple linear regression analysis indicated that nutritional management was principally responsible for improvements in nutritional status. The findings suggest that there has been a significant improvement in the nutritional status of the adult CF population, which may be due primarily to changes in nutritional management.

Adult↗

Eosinophilia at the time of respiratory syncytial virus bronchiolitis predicts childhood reactive airway disease.

OBJECTIVE: Bronchiolitis in infancy is viewed as a risk factor for childhood asthma, but factors predicting which infants will have persistent wheezing have not been identified. In addition, the nature of the association between the 2 conditions is uncertain. We wished to determine whether eosinophil counts at the time of acute bronchiolitis predicted the presence of wheezing in later childhood. METHODS: We retrospectively identified infants hospitalized with bronchiolitis, determined peripheral blood eosinophil counts at the time of bronchiolitis, and then contacted their families when they had reached 7 years of age. RESULTS: Eosinophil counts at the time of bronchiolitis were greater in subjects who would have wheezing at 7 years of age (median: 98 cells/mm(3)) than in infants who would have no recurrent wheezing (median: 0 cells/mm(3)) or transient wheezing only up to 3 years of age (median: 0 cells/mm(3)). When the effects of family history of asthma, gender, and passive exposure to cigarette smoke were examined, only eosinophilia at the time of bronchiolitis demonstrated a statistically significant relationship to the presence of wheezing at 7 years of age. CONCLUSIONS: Eosinophilia at the time of bronchiolitis generally predicts the development of wheezing persisting into later childhood. Therefore, the association of bronchiolitis and childhood asthma seems more likely to be attributable to an immunologic anomaly that precedes the development of, or is induced by, bronchiolitis rather than to structural damage to the airway as a result of bronchiolitis.

Bronchiolitis, Viral↗

Field anesthesia of free-living mountain gorillas (Gorilla gorilla beringei) from the Virunga Volcano region, Central Africa.

Twenty-six anesthetic procedures involving 24 free-living mountain gorillas (Gorilla gorilla beringei) from Rwanda or the Democratic Republic of Congo were performed between February 1987 and October 1997. Sixteen procedures were performed to remove snares or to treat snare-related wounds, and four of the animals died without recovering consciousness because of their severe medical conditions. Ketamine was used for induction 19 times, tiletamine/zolazepam was used five times, and the agent was not recorded for two procedures. The mean (+/- SD) ketamine dosage for four animals of known weight was 7.1 +/- 0.9 mg/kg. All induction agents were delivered i.m. by remote injection, and mean induction times for ketamine and tiletamine/zolazepam were 5.5 +/- 2.6 min (n = 12) and 5.4 +/- 3.7 min (n = 5), respectively. Mean recovery times were significantly shorter with ketamine compared with tiletamine/zolazepam (42.0 +/- 24.9 min, n = 9 vs. 75.25 +/- 22.1 min, n = 4). Low hemoglobin oxygen saturation (mean = 86.7%) was recorded in three cases under ketamine anesthesia, and oxygen insufflation is therefore recommended to prevent hypoxemia. Gorillas induced with tiletamine/zolazepam had significantly higher respiratory rates compared with animals given ketamine. Successful anesthesia and recovery, in particular, depended on the assistance of local personnel.

Anesthesia↗

Additional study of the Youth-Depression Adjective Check List.

Replicated and extended aspects of determinations of reliability and validity for the State version of the Youth-Depression Adjective Check List. Students from Grades 9 through 12 (64 girls and 41 boys) completed the State version and the Adolescent Activities Checklist on each of 12 consecutive days and completed the Trait version, the Reynolds Adolescent Depression Scale, the Multiple Affect Adjective Check List--Revised Grade 6, and the Adolescent Activities Checklist at the beginning and the end of the study. Good reliability and validity of the State version were confirmed and extended, and preliminary information on characteristics of the Trait version of the Youth-Depression Adjective Check List also was presented. The State version seems suitable for use in research with adolescents and preadolescents. More study of the Trait version is recommended.

Adolescent↗

Characterization of the surface proteins of influenza A (H5N1) viruses isolated from humans in 1997-1998.

Influenza A (H5N1) viruses infected humans in Hong Kong between May and December, 1997. Sixteen viruses, including 6 from fatal cases, were isolated during this outbreak. Molecular analysis of the surface proteins genes encoding the hemagglutinin (HA) and neuraminidase (NA) of these H5N1 isolates, of a subtype not previously known to infect humans, are presented. The 16 human H5 HA sequences contain multiple basic amino acids adjacent to the cleavage site, a motif associated with highly pathogenic avian influenza A viruses. The phylogenetic relationship among both avian and human H5 hemagglutinins indicates that the human isolates are related directly to isolates that circulated among chickens in the live poultry markets in Hong Kong prior to and during the outbreak in humans. HA sequences from the human isolates and a recent chicken isolate represent a separate clade, within which there are two subgroups that are distinguishable antigenically and by the presence of a potential glycosylation site. Likewise the N1 neuraminidases of the human H5 isolates represent a clade that is evolutionarily distinct from previously characterized N1 neuraminidases. The recent human H5N1 virus NA genes are avian-like, indicating direct introduction from an avian source rather than evolution of a human N1 NA. All of the 16 human NA genes encode a shortened stalk due to a 19-amino acid deletion, also found in the recent avian H5N1 isolates from Hong Kong. Two unique amino acids were identified in the N1 NAs of the recent human isolates; however, it is not known if these residues influence host range. Neither the HA nor the NA genes of the human H5N1 virus isolates show evidence of adaptive changes during the outbreak. Although analyses of the surface protein genes of the H5N1 viruses from this outbreak did not provide immediate answers regarding the molecular basis for virulence, the analyses provided clues to potentially important areas of the genes worth further investigation.

Adolescent↗

Homosexual parents: why appeals cases approximate the "gold standard" for science--a reply to Duncan.

Unlike the unverifiable claims of volunteers in studies of homosexual parenting, an alert ex-spouse is ready to testify as to the falsity of any claim by the other spouse in custody proceedings. Further, a greater variety of professionals are involved in getting at the "truth." We argue that examination of an unbiased corpus of such appeals cases is far more apt to reflect the underlying "reality" about homosexual parenting than studies performed on volunteers.

Homosexuality↗

Continuous assessment of the risk of falling using telecare.

The prevention of falls in the elderly could be based on risk assessment and the prediction of when an individual is likely to sustain an injury. A telecare system should allow the dynamic assessment of risk to be produced by a control centre computer, based on data transmitted from local sensors in the elderly person's home. A fall risk index could be calculated from mobility, activities of daily living and medication. However, substantial data-sets will be required before such fall risk indices attain statistical significance. As they are developed, fall prediction algorithms could be constantly reviewed and modified in order to reach the point where an acceptable level of accuracy is reached.

Accident Prevention↗

What proportion of newspaper stories about child molestation involves homosexuality.

Do homosexuals disproportionately molest children? A survey of 8 of the nation's newspaper news stories of child molestation during the first 9 months of 1995 showed that about 40% of child molestation stories in the major cities involve homosexuality. An Internet survey of FirstSearch for 1989 through 1995 indicated 46%, and of Newsbank for 1990 through 1995 60% of molestations were homosexual. About half of teachers, day care workers and other professionals caught molesting children assaulted them homosexually. It is argued that large unbiased sets of newspaper news stories appear to approximate the figures for incidence of child molestation by those occupying a newsworthy status but overreport homosexual molestation in general.

Adolescent↗

Homosexual parents: a comparative forensic study of character and harms to children.

40 appeals cases of custody disputes drawn systematically from all cases involving a homosexual parent in the United States were compared to 38 appeals cases involving heterosexual custody disputes drawn randomly from listings under parental "character" and 18 appeals cases drawn randomly from "general" cases in Dicennial Digest from 1966 to 1991. Each case involving homosexual vs heterosexual claimants was examined for recorded information about (1) the character of the homosexual parent, the associates of the homosexual parent, the heterosexual parent, and the associates of the heterosexual parent, (2) the effects, particularly harms, upon the child(ren), and (3) psychiatric opinion. 82% of the homosexual vs 18% of the heterosexual parents and 54% of the homosexual's associates vs 19% of the heterosexuals' associates were recorded as having poor character in cases involving a homosexual claimant. Of the 66 recorded harms, e.g., molestation, physical abuse, to the 73 children, homosexual persons accounted for 64 (97%). Of the 32 lesbians, 6 were recorded as having engaged in criminal activity and 3 of bringing false charges of child sexual abuse against the father. Psychiatric opinion, however, ran 25 to 12 in favor of custody for the homosexual parent. In the 56 heterosexual vs heterosexual comparison cases, 38% of the heterosexual parents and 28% of their associates were recorded as having poor character. Six harms to their 105 children and 3 instances of criminality but no false charges of sexual abuse were recorded. In the appeals court literature, homosexual parents were disproportionately of poor character and disproportionately associated with various harms to their children.

Adolescent↗