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T Coates

Publications and source records attributed to T Coates.

At least 19 recordsLinked to original sources
PubMed2004

Methane emissions from beef cattle: Effects of monensin, sunflower oil, enzymes, yeast, and fumaric acid.

Methane emitted from the livestock sector contributes to greenhouse gas (GHG) emissions. Understanding the effects of diet on enteric methane production can help refine GHG emission inventories and identify viable GHG reduction strategies. Our study focused on measuring methane and carbon dioxide emissions, total-tract digestibility, and ruminal fermentation in growing beef cattle fed a diet supplemented with various additives or ingredients. Two experiments, each designed as a 4 x 4 Latin square with 21-d periods, were conducted using 16 Holstein steers (initial BW 311.6 +/- 12.3 kg). In Exp. 1, treatments were control (no additive), monensin (Rumensin, Elanco Animal Health, Indianapolis, IN; 33 mg/kg DM), sunflower oil (400 g/d, approximately 5% of DMI), and proteolytic enzyme (Protex 6-L, Genencor Int., Inc., CA; 1 mL/kg DM). In Exp. 2, treatments were control (no additive), Procreatin-7 yeast (Prince Agri Products, Inc., Quincy, IL; 4 g/d), Levucell SC yeast (Lallemand, Inc., Rexdale, Ontario, Canada; 1 g/d), and fumaric acid (Bartek Ingredients Inc., Stoney Creek, Ontario, Canada; 80 g/d). The basal diet consisted of 75% barley silage, 19% steam-rolled barley grain, and 6% supplement (DM basis). Four large chambers (two animals per chamber) were equipped with lasers and infrared gas analyzers to measure methane and carbon dioxide, respectively, for 3 d each period. Total-tract digestibility was determined using chromic oxide. Approximately 6.5% of the GE consumed was lost in the form of methane emissions from animals fed the control diet. In Exp. 1, sunflower oil decreased methane emissions by 22% (P = 0.001) compared with the control, whereas monensin (P = 0.44) and enzyme had no effect (P = 0.82). However, oil decreased (P = 0.03) the total-tract digestibility of NDF by 20%. When CH(4) emissions were corrected for differences in energy intake, the loss of GE to methane was decreased by 21% (P = 0.002) using oil and by 9% (P = 0.09) using monensin. In Exp. 2, Procreatin-7 yeast (P = 0.72), Levucell SC yeast (P = 0.28), and fumaric acid (P = 0.21) had no effect on methane emissions, although emissions as a percentage of GE intake were 3% (non-significant, P = 0.39) less for steers fed Procreatin-7 yeast compared with the control. This study demonstrates that sunflower oil, ionophores, and possibly some yeast products can be used to decrease the GE lost as methane from cattle, but fiber digestibility is impaired with oil supplementation.

Animal Feed↗
PubMed2003

A review of research on the structure, process and outcome of liaison mental health services.

Liaison mental health services (LMHS) developed originally to address the mental health needs of people with physical illnesses in general hospitals and more recently to work also with people with mental health problems presenting at non-mental health services. The purpose of the present paper was to review empirical research on the structure, process and outcome of liaison mental health services using systematic review methods. Following a comprehensive search strategy, the authors reviewed 48 papers published between 1975 and 2001. There is an extensive international literature on LMHS, much of which describes the structure and process of liaison work. Studies evaluating the outcomes of liaison mental health services are fewer, and handicapped by methodological flaws, some of which are serious enough to cast doubts on the reported results. Professionals and clients value LMHS. LMHS based in accident and emergency (A & E) departments appear to ease the burden of general A & E staff, help clients access mental health services and reduce re-admission rates of people with mental health problems. There is little evidence supporting one model of configuring LMHS over another.

Emergency Service, Hospital↗
PubMed2001

National trends in condom use among at-risk heterosexuals in the united states.

Based on national level surveys, we examined data relevant to the United States' overall effort to prevent the spread of HIV among heterosexual adults. We examined changes in condom use among at-risk heterosexuals over the past decade. The observed increases over time in condom use across all heterosexual at-risk population segments are consistent with the observed (declines) trends in HIV and syphilis in the 1990s. These results and findings from prior studies suggest that U.S. efforts to facilitate condom use and contain HIV and related sexually transmitted disease (STD)-cofactors among adult at risk heterosexuals was succeeding over most of the 1990s. The absence of national level behavioral trend data after 1996, and the ambiguities of HIV spread suggest some caution in projecting trends into this century. National and local efforts need to be directed at sustaining behavioral change and conducting more rigorous studies on population trends in HIV/STD-related behaviors/pathogens.

Adolescent↗
PubMed2001

Positive and negative life events after counselling and testing: the Voluntary HIV-1 Counselling and Testing Efficacy Study.

INTRODUCTION: The results of the Voluntary HIV-1 Counselling and Testing Efficacy Study support the efficacy and cost-effectiveness of HIV voluntary counselling and testing (VCT) for reducing risk behaviors in three developing countries. METHODS: This report explores the social consequences of HIV VCT by examining the incidence of positive and negative life events at the first follow-up (an average of 7.3 months after recruitment). The incidence of positive and negative life events was compared between: (i) those who were randomly assigned to HIV VCT versus health information (HI); (ii) those who tested seronegative and those who tested seropositive; and (iii) those who disclosed their serostatus and those who did not. RESULTS: The occurrence of most negative life events was rare (0--4%); positive life events were more common (17--39%). With few exceptions, those assigned to HIV VCT were no more likely to experience negative life events than those who were assigned to HI. For individuals, positive serostatus was associated with increased support from health professionals, the break-up of a marriage and being neglected or disowned by their family. Serodiscordant couples with an HIV-positive woman were most likely to report the break-up of a marriage (20 versus 0--7% for other groups) and the break-up of a sexual relationship (45 versus 22--38% for other groups). Disclosure was associated with strengthening of a sexual relationship except for HIV-seropositive women. CONCLUSION: These findings, in combination with findings supporting the efficacy and cost-effectiveness of HIV VCT, support the dissemination of HIV VCT with appropriate support services in developing countries.

AIDS Serodiagnosis↗
PubMed2001

Hepatitis B vaccines: assessment of the seroprotective efficacy of two recombinant DNA vaccines.

BACKGROUND: In universal vaccination programs, when there is no postvaccination sero-1 logic assessment of response, there must be confidence that the vaccines used provide a high degree of seroprotection. OBJECTIVE: This parallel analysis of 2 recombinant hepatitis B vaccines (Engerix B and Recombivax/HB-Vax II) was conducted to review the seroprotective efficacy of each vaccine in defined populations. METHODS: Clinical studies of the 2 vaccines published as manuscripts or conference abstracts in the public domain between January 1986 and April 1999 were identified retrospectively by unrestricted screening of journals through BIOSIS, MEDLINE, and EMBASE and the Internet. Unpublished or internal company data were excluded to maintain impartiality. The studies were reviewed and analyzed. The studies were not assessed for quality other than a judgment of their eligibility for inclusion in the analysis. The primary outcome measure was the proportion of subjects in defined populations who showed an early seroprotective response to currently licensed vaccination schedules. Summary statistical analyses of seroprotective response rates and 95% CIs were calculated for each vaccine for each population. Seroprotective response was defined by an anti-hepatitis B surface antigen titer > or =10 IU/L measured between 1 and 3 months after the final vaccination. Because the study was designed specifically to review published immunogenicity data, safety data were not assessed. The study was not designed to demonstrate superiority of one vaccine over the other. RESULTS: A total of 181 clinical studies representing 32,904 vaccinated subjects were reviewed and analyzed, of whom 24,277 had been vaccinated with Engerix B and 8627 vaccinated with Recombivax/ HB-Vax II. Seroprotection was achieved in 20,060 subjects (95.8%) with Engerix B and in 7774 subjects (94.3%) with Recombivax/HB-Vax II in the normal population vaccinated according to currently licensed 3-dose schedules. In a subgroup analysis, response rates in health care workers were 6492 subjects (94.5%) for Engerix B and 3245 subjects (92.2%) for Recombivax/HB-Vax II. Children and adolescents (1-19 years) showed the highest response rates to vaccination (4612 [98.6%], Engerix B; 2292 [98.9%], Recombivax/HB-Vax II). A total of 2875 infants (<1 year) (95.8%) achieved seroprotection with Engerix B; 701 (88.5%) achieved seroprotection with Recombivax/ HB-Vax II. CONCLUSIONS: Hepatitis B vaccination programs using either Engerix B or Recombivax/HB-Vax II can achieve high seroprotective response rates, particularly in childhood and adolescence. Ideally, younger populations should be a primary target in current universal vaccination programs.

Adolescent↗
PubMed2000

Voluntary counseling, testing, and referral for HIV: new technologies, research findings create dynamic opportunities.

Programs for voluntary counseling and testing (VCT) for HIV play an increasingly important role in comprehensive prevention and care strategies. New technological advancements and behavioral interventions can improve the effectiveness of VCT as a tool for preventing new HIV infections and helping HIV-positive individuals access appropriate care. With growing consensus that early access to HIV therapy increases its effectiveness, and that individuals diagnosed with HIV reduce risk behavior, VCT has become integral to the continuum of HIV primary care. However, federal funding of VCT has declined, with concomitant decreases in numbers of people being tested. An estimated 200,000 people in the United States remain unaware that they are HIV positive, and many at-risk individuals do not seek out standard HIV counseling and testing services. To increase the acceptability and effectiveness of VCT, the authors recommend that VCT programs employ outreach programs offering anonymous testing to reach those at heightened risk of HIV infection, and to make rapid use of new technologies and counseling strategies to improve the reach and efficacy. Given the important role that VCT can play in both prevention and early treatment, the authors recommend significant increases in federal support.

Confidentiality↗
PubMed2000

Cost-effectiveness of voluntary HIV-1 counselling and testing in reducing sexual transmission of HIV-1 in Kenya and Tanzania.

BACKGROUND: Access to HIV-1 voluntary counselling and testing (VCT) is severely limited in less-developed countries. We undertook a multisite trial of HIV-1 VCT to assess its impact, cost, and cost-effectiveness in less-developed country settings. METHODS: The cost-effectiveness of HIV-1 VCT was estimated for a hypothetical cohort of 10000 people seeking VCT in urban east Africa. Outcomes were modelled based on results from a randomised controlled trial of HIV-1 VCT in Tanzania and Kenya. Our main outcome measures included programme cost, number of HIV-1 infections averted, cost per HIV-1 infection averted, and cost per disability-adjusted life-year (DALY) saved. We also modelled the impact of targeting VCT by HIV-1 prevalence of the client population, and the proportion of clients who receive VCT as a couple compared with as individuals. Sensitivity analysis was done on all model parameters. FINDINGS: HIV-1 VCT was estimated to avert 1104 HIV-1 infections in Kenya and 895 in Tanzania during the subsequent year. The cost per HIV-1 infection averted was US$249 and $346, respectively, and the cost per DALY saved was $12.77 and $17.78. The intervention was most cost-effective for HIV-1-infected people and those who received VCT as a couple. The cost-effectiveness of VCT was robust, with a range for the average cost per DALY saved of $5.16-27.36 in Kenya, and $6.58-45.03 in Tanzania. Analysis of targeting showed that increasing the proportion of couples to 70% reduces the cost per DALY saved to $10.71 in Kenya and $13.39 in Tanzania, and that targeting a population with HIV-1 prevalence of 45% decreased the cost per DALY saved to $8.36 in Kenya and $11.74 in Tanzania. INTERPRETATION: HIV-1 VCT is highly cost-effective in urban east African settings, but slightly less so than interventions such as improvement of sexually transmitted disease services and universal provision of nevirapine to pregnant women in high-prevalence settings. With the targeting of VCT to populations with high HIV-1 prevalence and couples the cost-effectiveness of VCT is improved significantly.

AIDS Serodiagnosis↗
PubMed1999

Cerebral white matter lesions in primary Sjögren's syndrome: a controlled study.

OBJECTIVE: To determine the prevalence of neurological and magnetic resonance imaging (MRI) abnormalities in a well defined population of unselected patients with primary Sjögren's syndrome (SS) and age and sex matched healthy patients. METHODS: Thirty patients with SS and 29 age and sex matched controls were examined by a neurologist and subsequently underwent MRI scanning with a 1.0 Tesla Siemens Impact MR scanner. Scans were graded by a neuroradiologist blinded to the clinical status of each subject. The number and location of white matter lesions > 3 mm in long axis (to exclude non-specific perivascular changes) were recorded for each subject. RESULTS: There was a significant increase in lesions detected by MRI in SS patients versus controls (p = 0.02) including deep white matter lesions (p = 0.03) and subcortical white matter lesions (p = 0.02). The presence of white matter lesions did not correlate with serum IgG or rheumatoid factor levels, or with presence of anticardiolipin antibodies. No subjects had symptoms or signs of serious neurological disease including multiple sclerosis, and corpus callosal lesions commonly seen in multiple sclerosis were notably absent in this study. CONCLUSION: Cerebral white matter lesions detected by MRI are more frequent in patients with primary SS than control subjects, yet do not appear to be associated with significant clinical manifestations. Although the pathological nature of these lesions is yet to be defined, their presence should not be over-interpreted.

Adult↗
PubMed1998

HLA class II phenotype controls diversification of the autoantibody response in primary Sjögren's syndrome (pSS).

The coexistence of anti-La (SS-B) and anti-Ro (SS-A) autoantibodies in pSS is probably explained by intermolecular spreading of autoimmunity toward different components of the La/Ro ribonucleoprotein (RNP). In order to evaluate the role of the HLA class II phenotype in controlling diversification of this autoantibody response, 80 patients with pSS were typed by polymerase chain reaction sequence-specific oligonucleotide (PCR-SSO) at the HLA class II loci DRB1, DQA1 and DQB1. Serum samples were examined for anti-La and anti-Ro by counterimmunoelectrophoresis and by ELISA using purified recombinant La and 60-kD Ro proteins. Patient sera were classified according to the extent of diversification of the anti-La, anti-Ro response including the presence or absence of precipitating anti-La antibodies. Immunogenic characteristics of these stratified groups were then studied. All patients with pSS, with or without autoantibodies to Ro and La, were found to have at least one of the HLA-DRB1 types DR2, DR3 or DR5. The HLA DR3-DQA1*0501-DQB1*02 (DR3-DQ2) haplotype was primarily associated with a diversified La/Ro RNP response containing precipitating autoantibodies to La (P<0.001); whereas the haplotype HLA DR2-DQA1*0102-DQB1*0602 (DR2-DQ1) was associated with a less diversified La/Ro RNP response containing non-precipitating (restricted epitope) anti-La autoantibodies (P<0.001). Anti-La-positive patients lacking both HLA-DR2 and HLA-DR3 all expressed the HLA-DQA1*0501 allele, which was present at increasing frequency with greater diversification of the anti-La/Ro autoantibody response. The association of distinct HLA haplotypes with different degrees of autoantibody diversification in patients with pSS suggests a model of HLA-restricted presentation of La/Ro peptide determinants to autoreactive helper T cells. We propose that non-precipitating anti-La responses are driven by limited intermolecular help from DR2-DQ1-restricted T helper cells recognizing Ro determinants. On the other hand, we speculate that the more diversified, precipitating anti-La responses obtain more efficient cognate T help from DR3-DQ2-restricted T helper cells recognizing La determinants, where HLA-DQA1*0501 may be a critical determinant for antigen presentation.

Alleles↗
PubMed1998

Cutaneous necrosis from calcific uremic arteriolopathy.

Calcific uremic arteriolopathy (calciphylaxis) is an uncommon complication of chronic renal failure that is associated with high morbidity and mortality. We report 16 patients (13 female) who presented between 1985 and 1996. All patients developed painful livido reticularis that progressed to cutaneous necrosis and ulceration (11 cases on the proximal extremities and five cases on the distal extremities). Two patients with predominately distal leg disease survived; the cause of death in the other 14 patients was sepsis (six patients), withdrawal from dialysis (three), cardiac arrest (three), and gastrointestinal hemorrhage (two). Mesenteric ischemia from intestinal vascular calcification occurred in two cases. Clinical factors identified included the use of warfarin therapy in seven cases and significant weight loss (>10% body weight) in seven cases in the 6 months preceding the development of calcific uremic arteriolopathy. Skin pathology was studied in 12 cases, with all showing calcific panniculitis and small vessel calcification. Electron microscopic spectral analysis of the mineral content of the calcific lesions in the subcutaneous tissue showed only calcium and phosphorous. In two cases, substitution of low molecular weight heparin for warfarin therapy resulted in clinical improvement. Current theories of pathogenesis and treatment are reviewed. This study confirms the high morbidity and mortality of calcific uremic arteriolopathy producing ischemic tissue necrosis while drawing attention to significant weight loss and warfarin therapy as risk factors for the development of ischemic tissue necrosis. Hyperbaric oxygen therapy warrants further study.

Adult↗