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S Barnett

Publications and source records attributed to S Barnett.

At least 37 records · Page 2Linked to original sources
PubMed2000

A comparison of vertical force and temporal parameters produced by an in-shoe pressure measuring system and a force platform.

OBJECTIVE: To investigate the ability of Pedar in-shoe system to measure vertical force accurately, by comparing it with the Kistler force platform. DESIGN: In vivo experiment in normal subjects. BACKGROUND: It has been suggested Pedar is highly reliable, but absolute accuracy of the system with regard to force measurement has not been comprehensively tested. METHODS: Sampling at 99 Hz, using five healthy subjects, simultaneous data were collected barefoot, and in three types of shoes (Trainers, Oxfords, Slip-on Deck Type). Six variables obtained from the force/time curve from each footstep were compared. RESULTS: The temporal data recorded by Pedar correlated well with that obtained using Kistler, with significant differences only in overall duration of the step in Deck shoes (P<0. 001) and Oxford shoes (P<0.01), and peak to peak barefoot (P<0.01). Pedar recorded a lower first peak force and mid-peak force in all cases (P<0.001). However, the magnitude of the 2nd peak force recorded by both systems was significantly different only in Trainers (P<0.05) and Oxford shoes (P<0.001). The impulse data obtained with Oxford shoes was not significantly different, although barefoot, Trainers and Deck shoes were significantly lower (P<0.001) for Pedar. CONCLUSIONS: In most cases, comparison of data recorded by the two systems provided good evidence for the accuracy and reliability of temporal measurements and second peak force measurements taken with the Pedar in-shoe system. Relevance In-shoe pressure data provides evidence for clinical decisions if the systems utilised are proven to be valid, repeatable and accurate. Comparison with an established force platform enables some assessment of these factors.

Adult↗
PubMed2000

Cancer screening in the elderly population.

This article reviews the current state of knowledge regarding cancer screening in the geriatric population. Care of the elderly requires knowledge of underlying physiologic changes, comorbidities, quality-of-life factors, and life expectancies. There is always the danger that ageism may prevent elderly cancer patients from receiving the proper treatment. On the other hand, overzealous treatment can lead to adverse results if elderly patients are not properly targeted based on current evidence of the benefits and risks of specific screening practices.

Age Factors↗
PubMed1999

Characterization of the human glutamate receptor subunit 3 gene (GRIA3), a candidate for bipolar disorder and nonspecific X-linked mental retardation.

The X-chromosome breakpoint in a female patient with a balanced translocation t(X;12)(q24;q15), bipolar affective disorder and mental retardation was mapped within the glutamate receptor 3 (GRIA3) gene by fluorescence in situ hybridization. The GRIA3 cDNA of 5894 bp was cloned, and the gene structure and pattern of expression were determined. The most abundant GRIA3 transcript is composed of 17 exons. An additional 5 exons (2a, 2b, 5a, 5b, and 5c) from the 5' end of the GRIA3 open reading frame were identified by EST analysis (ESTs AI379066 and AA947914). Two new polymorphic microsatellite repeats, (TC)(n=12-26) and (AC)(n=15-19), were identified within GRIA3 5' and 3'UTRs. No mutations were detected in families segregating disorders mapping across GRIA3, one with X-linked bipolar affective disorder (BP) and one with a nonspecific X-linked mental retardation (MRX27). To assess the possibility of the involvement of the GRIA3 gene in familial cases of complex BP, a large set of 373 individuals from 40 pedigrees segregating BP were genotyped using closely linked (DXS1001) and intragenic (DXS1212 and GRIA3 3' UTR (AC)(n))) GRIA3 STR markers. No evidence of linkage was found by parametric Lod score analysis (the highest Lod score was 0. 3 at DXS1212, using the dominant transmission model) or by affected sib-pair analysis.

Adult↗
PubMed1999

HIV-1 vaccine-induced immune responses which correlate with protection from SHIV infection: compiled preclinical efficacy data from trials with ten different HIV-1 vaccine candidates.

The specific immune mechanisms necessary and/or sufficient to elicit HIV-vaccine protection remain undefined. Utilising the SHIV rhesus macaque model the immunogenicity as well as the efficacy of ten different HIV-1 vaccine candidates was evaluated. Comparison of the immune responses induced, with the ability of the vaccine to protect from SHIV infection provided a means to determine which type of immune responses were necessary for protection. Vaccine candidates included VLPs, DNA, subunit protein with novel adjuvant formulations, ISCOMs and pox-virus vectors. Protection from SHIV infection was achieved in approximately half of the animals which received a primary intravenous cell-free challenge. The presence of CTL in the absence of other effector responses did not correlate with protection from this route and type of challenge. Virus neutralising antibodies (Nab) appeared to be necessary but alone were insufficient for protection. If Ag-specific IFN-gamma and/or IL-4 as well as lymphoproliferative (LP) responses were found with the lack of a detectable IL-2 response, then protection was not observed. Immunity correlated with the magnitude of Nab responses, beta-chemokines and as well as balanced, qualitative T-helper responses.

AIDS Vaccines↗
PubMed1999

Cross-subtype neutralizing antibodies induced in baboons by a subtype E gp120 immunogen based on an R5 primary human immunodeficiency virus type 1 envelope.

Global human immunodeficiency virus type 1 (HIV-1) diversity may require engineering vaccines to express antigens representing strains prevalent in the target population of vaccine testing. The majority (90%) of incident infections in Thailand are genetic subtype E, with a small percentage of subtype B infections in the intravenous drug user populations. We have evaluated and compared the binding and HIV-1 neutralizing properties of serum antibodies induced in baboons by CHO cell-expressed monomeric gp120 derived from a CCR5-using (R5) subtype E primary HIV-1CM235 or a CXCR4-using (X4) subtype B T-cell line-adapted (TCLA) HIV-1SF2 isolate. In contrast to the subtype-specific HIV-1 neutralizing antibodies induced with recombinant HIV-1SF2 gp120 (rgp120SF2), rgp120CM235 immunization induced antibodies capable of neutralizing both subtype E and subtype B TCLA HIV-1 isolates. However, neither immunogen induced antibodies capable of neutralizing primary HIV-1 isolates. Antibody induced by rgp120CM235 preferentially bound natively folded gp120 and retained strong cross-reactivity against multiple gp120 strains within subtype E as well as subtype B. In contrast, antibody responses to rgp120SF2 were directed predominantly to linear epitopes poorly exposed on native gp120 and had more limited cross-recognition of divergent gp120. Fine epitope mapping revealed differences in antibody specificities. While both rgp120CM235 and rgp120SF2 induced antibodies to regions within C1, V1/V2, V3, and C5, unique responses were induced by rgp120CM235 to multiple epitopes within C2 and by rgp120SF2 to multiple epitopes within C3, V4, and C4. These data demonstrate that strain and/or phenotypic differences of HIV-1 subunit gp120 immunogens can substantially alter antibody binding specificities and subsequent HIV-1 neutralizing capacity.

AIDS Vaccines↗
PubMed1999

Smoking and deaf adults: associations with age at onset of deafness.

Smoking is a major health problem whose prevalence in different populations is thought to be influenced by sociocultural and linguistic factors. Although smoking and hearing loss are positively correlated, little is known about the smoking habits of deaf populations. Using national survey data, this study determined the smoking prevalence in two socioculturally distinct deaf populations, based on age at onset of deafness. The smoking prevalence in each deaf population was compared to the smoking prevalence in the hearing population in multivariate analyses that adjusted for sociodemographics and health status. The smoking prevalence among postlingually deafened adults was not significantly different from that among hearing adults. Prelingually deafened adults were found to be less likely to smoke than hearing adults, even though they have less education and lower income, factors both associated with higher smoking prevalence in other populations. The lower smoking prevalence among prelingually deafened adults may be due to cultural differences or to limited access to English-language tobacco advertising.

Adult↗
PubMed1999

Pediatricians' response to the demand for school health programming.

OBJECTIVE: Because of the broad and increasing interest in school health, the American Academy of Pediatrics (AAP) surveyed its members to determine their awareness of school health education/programs, their level of participation, their desire to participate, and their resource needs to participate more effectively. METHODS: Self-administered questionnaires were mailed to a randomized representative sample of AAP members (N = 1602). Overall response rate was 64.5%. Some responses were stratified for analysis by gender; age (>45 years or </=45 years); practice area (urban, suburban, or rural); practice setting (solo, group, or hospital); and type of practice (general versus specialty). chi2 Tests were used to compare responses. RESULTS: Greater than half of the pediatricians who responded to the questionnaire were aware of school health education curriculum on risky adolescent behaviors in their community, counseling services (58%), school nursing services (63%), and screening services (71%); however, more than half were not aware of curriculum on injury/violence prevention, fitness, or whether a school health advisory council was available. Most pediatricians supported comprehensive school health education (pregnancy prevention, 82%; violence prevention, 77%; mental health, 56%). Also, respondents supported services (counseling, 76%; nutrition, 65%; screening/referral, 58%; school-based primary care, 58%). Although 22% of AAP pediatricians are currently working with local school programs, >70% wanted to become involved or more involved and needed information on how they may be able to participate. Only 25% believed they were adequately prepared. Two thirds believed school-based clinics were one of the best ways to reach underserved children and adolescents and should include preteens. CONCLUSION: AAP pediatricians want to become more involved with comprehensive school health programs. The ways in which they want to participate vary substantially. Most pediatricians thought they needed additional education. The AAP has developed recommendations for graduate medical education and continuing medical education for pediatricians to participate in integrated school health services.

Attitude of Health Personnel↗
PubMed1999

Telephone ownership and deaf people: implications for telephone surveys.

OBJECTIVES: This study was done to determine the prevalence of telephone ownership in different deaf populations and to explore its implications for telephone-based surveys. METHODS: Multivariate analyses, with adjustments for sociodemographics and health status, were done of National Health Interview Survey (NHIS) data from 1990 and 1991, the years in which the NHIS Hearing Supplement was administered. RESULTS: Prelingually deafened adults were less likely than members of the general population to own a telephone (adjusted odds ratio [AOR] = 0.35; 95% confidence interval [CI] = 0.15, 0.82), whereas postlingually deafened adults were as likely as members of the general population to own one (AOR = 1.00; 95% CI = 0.78, 1.28). CONCLUSIONS: Telephone surveys risk marginalizing prelingually deafened adults because of low telephone ownership and language barriers between the deaf and hearing communities.

Adult↗
PubMed1999

Experimental test of harmonic contribution to the thermal index for soft tissue.

Experimental data were gathered for the heating effect of an ultrasound beam propagating in water and incident on a thermal test object containing artificial tissue in which a fine-wire thermocouple was embedded close to the beam entrance. The extent of temperature elevations in the artificial tissue was limited by using a constant low value for spatial peak temporal average ultrasound intensity so that the medium did not denature. The adjusted (for continuous wave conditions) maximum temperatures reached in a fixed exposure time initially increased linearly with increase in the spatial peak pulse average ultrasound intensity, but, for the higher values of this parameter, exceeded that expected from a linear relationship. In addition to the fundamental frequency, significant higher frequencies were present in the beam at high intensities, which caused additional enhancement of the ultrasound heating. Calculations of W(DEG) for evaluation of the thermal index should include the evaluation of the heating contributions from all frequencies present in the beam.

Agar↗
PubMed1999

Clinical and cultural issues in caring for deaf people.

BACKGROUND AND OBJECTIVES: The clinical practice of family medicine is increasingly cross-cultural. Promoting culturally sensitive and competent health care is one of the goals of medical educators in guiding medical students and residents, as well as designing continuing education for family physicians. Working with minority communities is essential to meet that goal. The Deaf community is a linguistic and cultural minority group that is often overlooked. Working with the Deaf community to help develop cultural competency and sensitivity has potential benefits. This article introduces some of the sociocultural experiences of deafness and their relevance in health care settings.

Adult↗
PubMed1998

beta-chemokines and neutralizing antibody titers correlate with sterilizing immunity generated in HIV-1 vaccinated macaques.

One of the obstacles to AIDS vaccine development is the variability of HIV-1 within individuals and within infected populations, enabling viral escape from highly specific vaccine induced immune responses. An understanding of the different immune mechanisms capable of inhibiting HIV infection may be of benefit in the eventual design of vaccines effective against HIV-1 variants. To study this we first compared the immune responses induced in Rhesus monkeys by using two different immunization strategies based on the same vaccine strain of HIV-1. We then utilized a chimeric simian/HIV that expressed the envelope of a dual tropic HIV-1 escape variant isolated from a later time point from the same patient from which the vaccine strain was isolated. Upon challenge, one vaccine group was completely protected from infection, whereas all of the other vaccinees and controls became infected. Protected macaques developed highest titers of heterologous neutralizing antibodies, and consistently elevated HIV-1-specific T helper responses. Furthermore, only protected animals had markedly increased concentrations of RANTES, macrophage inflammatory proteins 1alpha and 1beta produced by circulating CD8(+) T cells. These results suggest that vaccine strategies that induce multiple effector mechanisms in concert with beta-chemokines may be desired in the generation of protective immune responses by HIV-1 vaccines.

AIDS Vaccines↗
PubMed1998

Principles for developing interdisciplinary school-based primary care centers.

A 50% increase has occurred in the number of school-based primary care centers (SBPCCs) in the United States since 1993-94. Public schools offer a well-established and respected community-based infrastructure within which health centers may feasibly be developed. SBPCCs have documented improved access to care for underserved children and some initial success in addressing the complex morbidities and associated behavioral risk factors of children and adolescents. This paper presents five working principles to help communities establish SBPCCs that link community health and social services with their educational system. The principles encompass community participation, early assessment of community needs, integration of health and human services with educational services through an interdisciplinary and interagency team approach, development of a business plan, and program evaluation. These principles reflect the experiences of 22 Texas communities which operate 76 SBPCCs. They should prove helpful to many other communities and states that propose to develop, finance, and evaluate school-based, interdisciplinary health care and prevention services.

Adolescent↗
PubMed1998

Colorectal cancer prevention. An approach to increasing compliance in a faecal occult blood test screening programme.

STUDY OBJECTIVE: The assessment of the uptake of colorectal cancer screening offered in a workplace setting. DESIGN: Employees were offered a free faecal occult blood test (Haemoccult). A repeat letter was sent two months later to non-responders. Those with positive tests were invited for colonoscopy. Compliance was measured according to age, sex, and occupational group and the effects of reinviting non-compliers investigated. SETTING: Leicester General Hospital, a large university teaching hospital. PARTICIPANTS: 990 employees aged 41 to 65 years. MAIN RESULTS: Total compliance was 46% with women participating more than men (49% v 34%, chi 2 = 12.2, p < 0.001). The difference was mostly because of women aged 41 to 50 years complying more than their male counterparts (48% v 24%, chi 2 = 15.5, p < 0.0001). Participation was highest in clinical support staff (56%), nurses (52%), and clerical workers (46%). Uptake by doctors (26%) and managers (26%) was significantly lower than by clinical support staff and nurses (chi 2 > 5.5, p < 0.02). Remailing raised compliance slightly from 43.6% to 46.3%. Four employees (1%) had positive faecal occult blood tests but three were negative on repeat testing with dietary restrictions. CONCLUSIONS: The government favours the development of health promotion programmes as stated in its document "Health at work in the NHS". The response in this study, showed methods to increase compliance must be developed if such programmes are to be successful. As uptake was similar to that in several community based programmes in general practice, workplace based programmes could offer a complementary method of delivering screening.

Adult↗
PubMed1997

Enhancement of immunodeficiency virus-specific immune responses in DNA-immunized rhesus macaques.

In contrast to results obtained with plasmid DNA vectors encoding antigens from viruses such as influenza and hepatitis B, plasmids coding for antigens from primate immunodeficiency viruses have elicited relatively weak antibody responses following gene gun-mediated DNA immunization of rhesus monkeys. In an effort to augment these responses, the importance of the immunization schedule was investigated, as well as the possible synergy that might result from boosting gene gun-primed animals with other routes of immunization. Here we demonstrate that endpoint gp120-specific antibody titers can be enhanced as much as tenfold by reducing the number of immunizations and lengthening the resting period between immunizations. In addition, boosting gene gun-primed animals with either recombinant subunits or gp120-expressing vaccinia recombinants resulted in synergistic responses.

AIDS Vaccines↗
PubMed1997

The Paediatric Cochlear Implant Program at the Hospital for Sick Children, Toronto.

Ontario has a province-wide program for provision of cochlear implants. Toronto's Hospital for Sick Children is one of three designated centres that service the paediatric population. This cochlear implant program was established in 1989. Since that time, 37 children (as of May 1996) have been provided with cochlear implants. The program also services Ontario residents who were implanted elsewhere. In the following, we provide a detailed description of the program, including the processes through which children are selected as candidates, the follow-up studies that we carry out, and the roles of various health care professionals involved. We present a demographic survey of our patient population to date, and discuss some of the important issues relating to candidacy.

Child, Preschool↗