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T Coates

Publications and source records attributed to T Coates.

At least 37 records · Page 2Linked to original sources
PubMed1996

Nonprecipitating anti-La(SS-B) autoantibodies in primary Sjögren's syndrome.

Anti-La(SS-B) precipitin-negative sera show a restricted epitope recognition and can be easily overlooked in routine laboratory testing. We have therefore determined the prevalence of nonprecipitating anti-La(SS-B) antibodies in patients with primary Sjögren's syndrome and studied their clinical and immunological associations. Clinical details were obtained from 68 patients with primary Sjögren's syndrome, and serum samples were examined by enzyme-linked immunosorbent assay using purified recombinant La, 60-kDa Ro, and 52-kDa Ro proteins and by counterimmunoelectrophoresis. Thirteen patients (19%) were identified with anti-La antibodies which were nonprecipitating. These patients had similar clinical findings to other groups of patients with Sjogren's syndrome, but had significantly lower rheumatoid factor and serum IgG levels than patients with anti-La precipitins. None of the patients with nonprecipitating anti-La antibodies had previously contained anti-La precipitins in their sera. Furthermore, they tended to have lower levels of antibodies directed against denatured 60-kDa Ro (but not 52-kDa Ro) compared with anti-La precipitin-positive patients. Patients with Sjögren's syndrome associated with nonprecipitating anti-La antibodies represent a stable serological and clinical subset in which there appears to be limited diversification of the autoimmune response to the Ro60 and La proteins of the Ro/La ribonucleoprotein.

Antibodies, Antinuclear↗
PubMed1996

Rapid and sensitive detection of anti-Ro (SS-A) antibodies by indirect immunofluorescence of 60kDa Ro HEp-2 transfectants.

Anti-Ro (SS-A) antibodies are important diagnostic markers for primary Sjögren's syndrome and systemic lupus erythematosus, but their detection by indirect immunofluorescence (IF) in the diagnostic laboratory is hindered by the low cellular abundance of 60kDa Ro protein (Ro60). The approach we used to overcome this problem was to transfect and over-express the Ro60 gene into HEp-2 cells. In this study we have used a mixture of Ro60 transfectants and untransfected HEp-2 cells (HEp-Ro60) as a substrate for IF-antinuclear antibody (ANA) testing in a hospital laboratory. Screening of 240 routine serum specimens identified 14 Ro transfectant-positive sera which were confirmed by counterimmunoelectrophoresis (CIE); 3 of these sera were ANA-negative on untransfected cells and regular HEp-2. A comparison of HEp-Ro60 and regular HEp-2 showed strong concordance of the different ANA patterns between the 2 substrates. No increase in background staining was observed on the Ro transfectants when reacted with normal human sera. A comparison between HEp-Ro60 and CIE for 53 sera from patients with primary Sjögren's syndrome showed that HEp-Ro60 were a sensitive and specific substrate for detection of anti-Ro antibodies. Masking of positive Ro transfectants was observed rarely in sera containing multiple ANA specificities, but the Ro60 staining on these transfectants were unmasked at higher serum dilutions. We conclude that HEp-Ro60 are a suitable substrate for IF-ANA in the routine laboratory and that they have the additional advantage over regular HEp-2 slides of being able to detect anti-Ro in ANA-negative sera. HEp-RO60 are also a valuable confirmatory test for sera giving equivocal precipitin reactions or ELISA results.

Adult↗
PubMed1995

Increased neutrophil respiratory burst in bcr-null mutants.

Philadelphia (Ph)-positive leukemias invariably contain a chromosomal translocation fusing BCR to ABL. The BCR-ABL protein is responsible for leukemogenesis. Here we show that exposure of bcr-null mutant mice to gram-negative endotoxin led to severe septic shock and increased tissue injury by neutrophils. Neutrophils of bcr (-/-) mice showed a pronounced increase in reactive oxygen metabolite production upon activation and were more sensitive to priming stimuli. Activated (-/-) neutrophils displayed a 3-fold increased p21rac2 membrane translocation compared with (+/+) neutrophils. These results connect Bcr in vivo with the regulation of Rac-mediated superoxide production by the NADPH-oxidase system of leukocytes and suggest a link between Bcr function and the cell type affected in Ph-positive leukemia.

Actin Cytoskeleton↗
PubMed1995

Bee venom hypersensitivity and its management: patients perception of venom desensitisation.

The objectives of the study were to review bee venom immunotherapy from the patient's perspective: in particular its benefits and its problems, and to investigate any genetic tendency for bee venom hypersensitivity. A self administered, 9 item questionnaire was sent to 219 patients who had undergone either inpatient or outpatient bee venom immunotherapy at Flinders Medical Center. The clinic records of these patients were also reviewed. The controls for the genetic study were sought from patients, staff and students at Flinders University and Flinders Medical Centre. One hundred and forty-six questionnaires (some incomplete and anonymous) were received. The female to male ratio was 1:2.5. The age at the time of the initial anaphylactic reaction to a bee sting ranged between 2 to 59 years, with 67% of patients being less then 20 years old. Forty percent of patients underwent venom immunotherapy for a period less than 2 years with only 11% maintaining therapy for the recommended period of 5 years or more. Thirty three percent of patients stopped their therapy on their own accord. Bee stings occurring during bee venom immunotherapy (n = 56) were generally well tolerated except in 8 subjects, 7 of whom had not reached the maintenance dose. The reduction in systemic reactions to subsequent bee stings was significantly better in the study group receiving bee venom than in an historic control group treated with whole bee extract (p = 0.03). Fear of bee stings and restricted life styles were improved during or after venom immunotherapy. The frequency of a positive family history of systemic reactions to bee stings in the patient cohort was 31%, whereas in controls it was 15% (p = 0.013). Bee venom immunotherapy has dual benefits: patients are protected from subsequent sting anaphylaxis and there is reduced psychological morbidity. However, to be effective, venom immunotherapy requires a prolonged period of carefully supervised treatment and each venom injection can cause local and systemic side effects. Genetic factors appear to be present in those patients who develop immediate hypersensitivity to be stings.

Adolescent↗
PubMed1994

The 47-kD protein increased in neutrophil actin dysfunction with 47- and 89-kD protein abnormalities is lymphocyte-specific protein.

A male child born of related parents suffered recurrent infections because of neutrophil actin dysfunction with increased amounts of a 47-kD protein and decreased amounts of an 89-kD protein (NAD 47/89). The patient and family members were studied to define the nature of the abnormal proteins and to examine their role in the functional defects of neutrophil actin dysfunction (NAD) 47/89 polymorphonuclear neutrophils (PMNs). NAD 47/89 PMNs are defective in motility, microfilamentous cytoskeletal structure, and formyl peptide-induced actin polymerization and express increased amounts of a 47-kD protein and decreased amounts of an 89-kD proteins intermediate abnormality in amount of 47-kD and 89-kD proteins in PMNs from parents and a female sibling suggest the disease is an autosomal recessive disorder. Immunoblots with monoclonal antibody (MoAb1) and polyclonal antibody raised to 47-kD protein showed the 89-kD protein is antigenically distinct from the 47-kD protein and the 89-kD protein is not gelsolin. 125I-actin binding to one-dimensional (1 D) and 2 D gels of PMN proteins from NAD 47/89 proband, family members, and controls showed the 47-kD protein binds actin, is acidic (pl = 4.5 to 4.7), is recognized by the MoAb1, exists on 2-D gels as three distinct actin binding species (MWapp 52 kD, 47-kD, and 44-kD), and is present in control PMNs in lesser amount than in PMNs of NAD 47/89 proband or parents. Immunoaffinity purification of the 47 kD actin binding protein on MoAb1 matrix yielded a multimolecular complex with proteins of MWapp 180 kD, 71 kD, 47 kD and actin. Cloning, sequencing, and expression of a 1.58-kb cDNA selected for MoAb1 reactivity from a HL60 expression library and microsequence of native PMNs, 47-kD actin binding protein showed the overexpressed 47-kD protein is lymphocyte-specific protein 1 (LSP1), which is a known actin binding protein. The results show LSP1 is expressed in PMNs and suggest overexpression of LSP1 is related to the motility and cytoskeletal abnormalities in NAD 47/89 PMNs.

Actins↗
PubMed1993

Stress, control, coping, and depressive mood in human immunodeficiency virus-positive and -negative gay men in San Francisco.

This study examined the relationship between stress, appraised control, and coping and depressive mood in 425 human immunodeficiency virus-positive and -negative gay men in San Francisco. Depressive mood was assessed by self-report in 1988 and 1989. Participants were also surveyed in 1989 on the stress in their lives, their appraised control over the stress, and the ways they coped. Depressive mood in 1988 and symptoms of human immunodeficiency virus disease in 1989 accounted for 50% of the variance in 1989 depressive mood; stress, appraised control, and coping accounted for an additional 10% of the variance in depressive mood in 1989. Path analysis indicated: stress appraised as controllable was associated with involvement coping, which in turn was associated with diminished depressive mood; stress associated with detachment was associated with increased depressive mood; and stress was also directly associated with increased depressive mood.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Confidential HIV testing and condom promotion in Africa. Impact on HIV and gonorrhea rates.

OBJECTIVE: We evaluated the impact of human immunodeficiency virus (HIV) testing and counseling on self-reported condom and spermicide use and on corresponding HIV seroconversion and gonorrhea rates in urban Rwandan women. DESIGN: Prospective cohort study with 2 years of follow-up, comparison of outcome variables before and after an intervention, and condom use measured in a control group that did not receive the intervention. SETTING: Outpatient research clinic in Kigali, the capital of Rwanda. PARTICIPANTS: One thousand four hundred fifty-eight childbearing women, 32% of whom were infected with HIV, were enrolled in a prospective study in 1988, and followed at 3- to 6-month intervals for 2 years. Follow-up was available for 95% of subjects at year 1 and 92% at year 2. INTERVENTIONS: An acquired immunodeficiency syndrome (AIDS) educational videotape, HIV testing and counseling, and free condoms and spermicide were provided to all participants and interested sexual partners. MAIN OUTCOME MEASURES: Self-report of compliance with condom-spermicide use and observed incidence of HIV and gonorrhea. RESULTS: Only 7% of women reported ever trying condoms before the intervention, but 22% reported condom use with good compliance 1 year later. Women who were HIV-positive were more likely to adopt condom use than HIV-negative women (36% vs 16%; P < .05). Independent predictors of condom use, both in HIV-positive and in HIV-negative women, included HIV testing and counseling of the male partner, having a nonmonogamous relationship, and believing condoms were not dangerous. Human immunodeficiency virus seroconversion rates decreased significantly (from 4.1 to 1.8 per 100 person-years; P < .04) in women whose partners were tested and counseled. The prevalence of gonorrhea decreased substantially (13% to 6%; P < .05) among HIV-positive women, with the greatest reduction among condom users (16% to 4%; P < .05). CONCLUSION: A confidential HIV testing and counseling program was associated with increased use of condoms and reduced rates of gonorrhea and HIV in urban Rwandan women. The lack of risk reduction in HIV-negative women whose partner's serostatus was unknown was of concern. Interventions that promote HIV testing and counseling for both members of a couple should be considered in other high-prevalence areas.

AIDS Serodiagnosis↗
PubMed1992

Prolonged clinical response to vincristine treatment in two patients with idiopathic hypereosinophilic syndrome.

Idiopathic hypereosinophilic syndrome (HES) is a rapidly progressive disease that can result in death within weeks to months of diagnosis in untreated patients. We report two pediatric cases of HES. One patient has remained clinically and hematologically stable for 9 years with vincristine and 6-thioguanine (6TG), and the other has received vincristine alone for 6 months with a good response. The use of long-term vincristine and 6TG or vincristine alone has not been previously reported in the management of HES in children. Vincristine administered every 3-4 weeks with or without 6TG can produce a reduction in the overall white cell count and improvement of symptoms of hypereosinophilia. Although the mortality of patients with HES is high, aggressive treatment can result in significant clinical benefit and improved prognosis in children with this syndrome.

Child, Preschool↗
PubMed1991

Knowledge, attitudes, and perceived risk of AIDS among urban Rwandan women: relationship to HIV infection and behavior change.

We examined factors associated with perceived risk of AIDS, behavior change, and HIV infection in a representative sample of 1458 child-bearing urban women in Rwanda, central Africa. Although 68% of women reported only one lifetime partner, and the majority (87%) lived with a husband or steady partner, the prevalence of HIV antibodies was still high (32%). Before receiving their HIV test results, the women completed a questionnaire about AIDS knowledge, attitudes, and practices. Knowledge about HIV transmission was high, with 96-98% of women correctly identifying the three primary routes of infection. However, only 16% of women reported taking any action to avoid AIDS in the previous year, and most (11%) had done so merely by asking their male partners to change their behavior. Only 7% of women had ever tried condoms, and many (68%) thought they could be dangerous to use. Women who perceived themselves at risk of AIDS (57%) were more likely to report changing behavior; they were also more likely to be infected with HIV. Other factors associated with behavior change included having known someone with AIDS, having discussed AIDS with a male partner, and believing that condoms are not dangerous. Future interventions should enhance perception of risk, encourage male sexual partners to reduce risky behavior, and increase familiarity with condoms.

Adolescent↗
PubMed1989

Comparison of beliefs about AIDS among urban, suburban, incarcerated, and gay adolescents.

Beliefs about AIDS were surveyed among opportunistic samples of 1572 adolescents to compare four subgroups of youth: urban public high school students; suburban private school students; youth incarcerated in a detention facility; and a group who were contacted through a gay youth organization. The questionnaire items formed four important theoretical constructs derived by an expert group extensively involved with AIDS education. The constructs were: 1) agreement with health guidelines; 2) perceived personal threat of AIDS; 3) a sense of personal efficacy to prevent infection and the spread of AIDS; and 4) perceived norms of safe sex behaviors. In all groups, females were more likely to endorse higher norms for safe sex practices than males. Older adolescents of both sexes tended to perceive less personal threat of AIDS, and also rated lower norms for safe sex practices than did the younger adolescents. The incarcerated group of adolescents demonstrated significantly poorer knowledge and lower agreement with health guidelines (p = 0.0000), lower perceived personal threat of AIDS (p = 0.005), lower personal efficacy to prevent AIDS (p = 0.003), and lower perceived norms of safe sex practices (p = 0.0000), compared to the other groups. The education implications of these findings are discussed, including the necessity of program elements directed toward subculture peer norms and support, a realistic sense of vulnerability about AIDS, and self-confidence building as well as specific skills to prevent the infection and spread of the human immunodeficiency virus among adolescents.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Dentists as smoking cessation counselors.

Dentists can help people quit smoking because they are experts in oral health, are accustomed to counseling about oral preventive health, and have broad exposure to the general populace. To determine dentists' counseling practices with regard to smoking cessation, a randomly selected sample of 82 dentists practicing in the San Francisco Bay Area were surveyed. Also 106 internists in the same region were surveyed. Whereas the dentists believed smoking is dangerous to health and considered counseling as an important part of their practice, only 17%, compared with 58% of the internists, frequently discussed quitting with their patients who smoke. The two groups also differed in the types of counseling they used. Dentists attributed their lack of counseling to poor insurance coverage, insufficient time, lack of training, and fear that patients might leave their practices if urged to quit. These issues must be addressed if dentists are to participate fully in helping their patients quit smoking.

Adult↗
PubMed1986

Hodgkin disease and non-Hodgkin lymphomas in children: utilization of radiological modalities.

If costs of medical care are to be reduced, the choice of which imaging modality to use must be made as carefully as possible. This study was done to show how radiological modalities were used to evaluate patients with Hodgkin disease and non-Hodgkin lymphoma. We kept a record of every radiological study performed on 66 children with both diseases seen in the past 6 1/3 years. The results of these studies were analyzed to see which areas of the body were studied, which imaging modality was used, how frequently the studies were repeated, and how frequently the studies gave abnormal results. Our findings disclosed that radiological studies have been appropriately performed in anatomic regions of the body in which disease is present. New imaging modalities have been introduced, and the use of some of the older modalities has been decreased. With some modalities, such as skeletal survey, liver/spleen scan, whole-lung tomography, contrast studies of the bowel, and excretory urography, utilization is higher than it ought to be in view of the fact that the yield of positive results is low and the information is obtainable in many cases from other more sensitive procedures. These studies should not be performed as a routine on initial evaluation or follow-up of all patients with Hodgkin or non-Hodgkin lymphomas. On initial presentation all patients should undergo chest radiography and CT scanning of both chest and abdomen. A problem area is that the timing of follow-up studies has been somewhat erratic, with some inappropriate studies particularly 3 or 4 years after diagnosis. Too many imaging procedures have probably been done in follow-up of our patients.

Bone Marrow↗
PubMed1985

Magnetic resonance imaging of lymphomas in children.

Magnetic resonance imaging has been used to evaluate 10 children with lymphomas and was able to identify disease in all 10 cases and monitor response to therapy in all three patients with follow-up studies. It could not distinguish between the different histological types of lymphoma. The image intensity of a diseased spleen in one case was different from that of five other normal spleens in six children with Hodgkins disease. Magnetic resonance imaging compared well with computed tomography and it was especially good at identifying blood vessels.

Adolescent↗
PubMed1984

Magnetic resonance imaging of bone marrow disease in children.

Seven children underwent magnetic resonance imaging (MRI) of the bone marrow: results showed that it is technically feasible to obtain good MR images of marrow in children. MR has detected abnormality in the bone marrow of a child who had metastatic neuroblastoma. The extent of abnormality in the femur correlated well with findings of a bone marrow isotope scan. In one child who had idiopathic aplastic anemia, diseased marrow could not be distinguished from normal marrow on MR images. MRI identified abnormality of the marrow in osteogenic sarcoma, and demonstrated change in response to chemotherapy. It displayed marrow spread of tumor as well as CT. MRI showed marrow abnormality in four children who had leukemia.

Anemia, Aplastic↗
PubMed1981

Molecular analysis of the beta-thalassemia phenotype associated with inheritance of hemoglobin E (alpha 2 beta2(26)Glu leads to Lys).

Inheritance of the gene for betaE-globin is associated with hypochromia and microcytosis, reminiscent of typical heterozygous beta-thalassemia. Patients with hemoglobin (Hb)E-beta-thalassemia exhibit clinical phenotypes of severe beta-thalassemia, a circumstance not encountered in other compound heterozygous states for structural beta-chain mutations and beta-thalassemia. We have analyzed the kinetics of globin synthesis and the levels of globin messenger (m) RNA accumulation in patients with Hb E-beta-thalassemia and Hb E trait. The initial rate of beta-globin synthesis (betaE/alpha=0.20-0.34) was less than expected on the basis of gene dosage, or comparable studies of other compound heterozygous states for beta-thalassemia and structurally abnormal beta-chains. betaE-globin synthesis was not only reduced during short-term incubations (1-5 min), but also remained relatively unchanged during long-term pulse or chase incubations up to 5h. Analysis of globin mRNA by cell-free translation and molecular hybridization confirmed that the unexpectedly low levels of betaE-globin synthesis were associated with comparable reduction in the levels of beta-globin mRNA. In Hb E-beta-thalassemia the betaA + betaE (alpha globin nRNA ratio observed were substantially lower than those obtained from reticulocytes of patients with heterozygous beta-thalassemia, or Hb S-betaO-thalassemia, while in Hb E trait, the betaA + betaE/alpha mRNA ratio was in the ranged observed for beta-thalassemia trait. The betaE-globin gene specifies reduced accumulation of betaE-globin mRNA, a property characteristic of other forms of beta-thalassemia. The beta-thalassemia phenotype associated with inheritance of Hb E is thus determined at the level of beta-globin mRNA metabolism.

Globins↗