Search PubMed⌕ Search

Biomedical subjects

S M Taylor

Publications and source records attributed to S M Taylor.

At least 73 records · Page 4Linked to original sources
PubMed1998

Geographical variation in attitudes towards smoking: findings from the COMMIT communities.

This paper examines the links between attitudes towards cigarette smoking and the social environments of communities involved in the U.S. National Cancer Institute's Community Intervention Trial for Smoking Cessation (COMMIT). Our objective is to identify sources of social-geographic variation in smoking attitudes and norms which can hinder or enhance public health efforts to reduce tobacco use. The analysis had two stages: (1) place (measured as region and community) was identified as an important main effect accounting for individual variation in smoking attitudes independent of smoking status and personal characteristics; (2) case studies of COMMIT sites in North Carolina, Iowa, Washington, New Jersey and New Mexico were conducted to reveal features of the local milieux which could account for variations in smoking attitudes. Some of the place characteristics that we suggest are linked to local attitudes include economic reliance on the tobacco industry, libertarian political orientations, socio-economic conditions, legislative context and ethnic composition. Given the effects of regional and community attributes on individual attitudes towards smoking, we conclude that public health efforts to control smoking should continue to be targeted beyond individual smokers to the broader social environment.

Analysis of Variance↗
PubMed1998

Vascular leakage stimulates phenotype alteration in ocular cells, contributing to the pathology of proliferative vitreoretinopathy.

Plasma leaking from damaged retinal blood vessels can have a significant impact on the pathologies of the posterior segment of the eye. Inflammation in the eye and metabolic change resulting from diabetes mellitus causes vascular leakage with alteration of the phenotype of retinal pigment epithelial (RPE) cells and fibrocytes, resulting in changes in cell function. Phenotypically altered cells then significantly contribute to the pathogenesis of retinopathies by being incorporated into tractional membranes in the vitreous, where they secrete matrix molecules, such as fibronectin, and express altered cell surface antigens. We hypothesize that there is a direct relationship between the leaking of plasma and the proliferation and phenotypic change of RPE cells and fibroblasts, thus exacerbating the pathology of retinal disease. If the hypothesis is correct, control of vascular leakage becomes an important target of therapy in proliferative vitreoretinopathy.

Animals↗
PubMed1998

Community Intervention Trial for Smoking Cessation (COMMIT): changes in community attitudes toward cigarette smoking.

The success of the Community Intervention Trial for Smoking Cessation (COMMIT) in changing smoking attitudes is examined by testing two primary hypotheses: (1) the priority of smoking as a public health problem increased more in the intervention communities than in the comparison communities, and (2) norms and values that support non-smoking increased more in the intervention than in the comparison communities. One community within each of 11 matched pairs was randomly assigned to receive a 4-year (1989-92) community-based smoking control intervention. Community attitudes towards smoking were measured primarily by cross-sectional surveys in 1989 (n = 9875) and 1993 (n = 14117) but a cohort (n = 5450) also provided attitude information. The main trial effect was on heavy smokers in the intervention communities who showed significantly more change in their beliefs about smoking as a public health problem. Despite the absence of an intervention-comparison difference, the magnitude of change in community-wide norms and values was related to the level of smoking control activities. In the cohort, light-to-moderate smokers in the intervention communities came to have stronger beliefs about smoking as a serious public health problem. COMMIT's impact on the beliefs of heavy smokers about the seriousness of smoking as a public health problem has important public health implications.

Adult↗
PubMed1998

Measuring attitudes towards smoking in the Community Intervention Trial for Smoking Cessation (COMMIT).

We present the development of indices using baseline data from the Evaluation Survey for the Community Intervention Trial for Smoking Cessation (COMMIT). The indices are designed to measure two primary attitude constructs that relate to smoking behavior: beliefs about smoking as a public health problem (SPHP); and norms and values concerning smoking (NVS). Two general approaches to index construction, the rational method and the factor analytic method, were used. Item analysis suggested good internal consistency for both indices (alpha > 0.75). Seven subconstructs emerged from the factor analysis accounting for 55.0% of the total variance. The SPHP and NVS items uniquely identify with four factors and three factors, respectively, confirming the validity of the two indices. Confirmatory factor analyses of a different data set provided further validation. Validity was also assessed by an examination of the relationships between index scores and smoking status. Smokers reported significantly higher scores than non-smokers on the two measures indicating, as anticipated, that smokers have more favorable attitudes towards smoking than non-smokers. These findings suggest that the two a priori constructs of SPHP and NVS are empirically distinguishable components of attitudes towards smoking, and that the indices developed here are reliable and valid measures of those constructs.

Adult↗
PubMed1998

Assessing public health capacity to support community-based heart health promotion: the Canadian Heart Health Initiative, Ontario Project (CHHIOP).

This paper presents initial findings of the Canadian Heart Health Initiative, Ontario Project (CHHIOP). CHHIOP has two primary objectives. The programmatic objective is to coordinate and refine a system for supporting effective, sustained community-based heart health activities. This paper addresses the scientific objective: to develop knowledge of factors that influence the development of predisposition and capacity to undertake community-based heart health activities in public health departments. A systems theory framework for an ecological approach to health promotion informs the conceptualization of the key constructs, measured using a two-stage longitudinal design which combines quantitative and qualitative methods. This paper reports the results of the first round of quantitative survey data collected from all health departments in Ontario (N = 42) and individuals within each health department involved in heart health promotion (n = 262). Results indicate low levels of implementation of heart health activities, both overall and for particular risk factors and settings. Levels of capacity are also generally low, yet predisposition to undertake heart health promotion activities is reportedly high. Analyses show that implementation is positively related to capacity but not predisposition, while predisposition and capacity are positively related. Overall, results suggest predisposition is a necessary but not sufficient condition for implementation to occur; capacity-related factors appear to be the primary constraint. These findings are used to inform strategies to address CHHIOP's programmatic objective.

Causality↗
PubMed1998

Pirfenidone reduces fibronectin synthesis by cultured human retinal pigment epithelial cells.

PURPOSE: Pirfenidone is a novel anti-fibrotic drug that has been shown to inhibit fibroblast growth and collagen synthesis induced by transforming growth factor (TGF)-beta1. In the present study we investigated the ability of pirfenidone to moderate fibronectin synthesis by cultured human retinal pigment epithelial (RPE) cells maintained in media containing 1% foetal bovine serum when stimulated with TGF-beta1. METHODS: Primary human RPE cultures were used. Treatments included TGF-beta1, pirfenidone and pirfenidone with TGF-beta1. After 72 h treatments, cell growth was determined by cell counting and fibronectin was measured by ELISA. RESULTS: Transforming growth factor-beta1 (1-10 ng/mL) increased the production of soluble fibronectin, while pirfenidone (300 micromol/L) significantly reduced the TGF-beta1-induced synthesis of fibronectin. Pirfenidone alone had no effect on fibronectin synthesis by cultured RPE cells. CONCLUSION: We conclude that the anti-fibrotic effect of pirfenidone may be partly mediated through inhibition of TGF-beta1-induced fibronectin synthesis.

Antineoplastic Agents↗
PubMed1998

Factors associated with limb loss despite a patent infrainguinal bypass graft.

Lower-extremity limb salvage should parallel infrainguinal bypass graft patency. To determine factors associated with limb loss despite a patent bypass, we reviewed 191 consecutive infrainguinal bypasses in 158 patients followed prospectively over 42 months. In this series of 176 (92%) vein grafts, 15 (8%) expanded polytetrafluoroethylene grafts, 122 (64%) tibial artery bypasses, and 170 (89%) bypasses placed for limb salvage, 29 major lower-extremity (above-knee or below-knee) amputations were performed in 29 patients, 12 because of ischemia after graft thrombosis and 17 (9% of series) due to progression of soft tissue infection/necrosis despite a functioning bypass. Primary and secondary 36-month vein graft patencies by life-table analysis were 61 per cent and 81 per cent, respectively. When the 17 cases of limb loss were compared to the rest of the series, nonstatistically significant variables included male sex [11 (65%) vs 79 (56%); P = 0.608] and diabetes [12 (71%) vs 80 (57%); P = 0.310]. Statistically significant variables included black race [9 (53%) vs 39 (28%); P = 0.048]; chronic renal failure [6 (35%) vs 12 (9%); P = 0.005], placement to a tibial/pedal artery [15 (88%) vs 107 (62%); P = 0.034], distal anastomosis to the anterior tibial/dorsalis pedis (AT/DP) artery [8 (47%) vs 27 (16%); P = 0.004], and grafts requiring late revision [7 (41%) vs 22 (13%); P = 0.006]. Thirteen (76%) extremities had an intact pedal arch. Nine amputations were performed within 30 days (early group), and eight were performed from 45 days to 20 months (median, 8 months) after bypass placement (late group). The most common primary causes of limb loss in the early group were overwhelming progression of soft-tissue infection despite patent bypass (n = 4; 44%) and insufficient runoff in the foot (n = 3; 33%). In the late group, amputation most often followed long treatment of a chronic proximal diabetic neuropathic foot ulcer with osteomyelitis. Five (63%) grafts in this group were anastomosed to the AT/DP arteries. These data suggest that patients with chronic renal failure, chronic neuropathic heel ulcers, and an AT/DP bypass are at greater risk for amputation despite a working bypass, especially if the graft develops a hemodynamically significant stenosis. Careful judgment and patient selection under these circumstances are thus justified.

Adult↗
PubMed1998

Oslerus osleri tracheobronchitis: treatment with ivermectin in 4 dogs.

Oslerus osleri tracheobronchitis was diagnosed in 4 young dogs following endoscopic visualization of tracheal nodules and identification of larvae in airway cytologic samples. All dogs improved when ivermectin was administered (200-400 micrograms/kg body weight); however, most (3/4) required serial treatments in order to achieve long-term resolution of clinical signs.

Animals↗
PubMed1997

Protection against Dictyocaulus viviparus in second year cattle after first year treatment with doramectin or an ivermectin bolus.

Forty-five calves were assigned randomly to three groups of 15 at turnout (day 0) in the spring of their first grazing season on to separate paddocks on a pasture known to carry infective larvae of Dictyocaulus viviparus. Group 1 calves were left as untreated controls, group 2 were injected with doramectin at 200 micrograms/kg at turnout and again on day 56, and group 3 were treated with an intraruminal bolus containing ivermectin. From day 42 onwards group 1 calves developed parasitic bronchitis which required repeated treatment with levamisole. The two endectocide regimes controlled lungworm infection, although some calves in group 2 developed some coughing during the week before the second dose of doramectin. After the end of the grazing season and again in May of the following year, five cattle from each group were infected experimentally with lungworm larvae and slaughtered 28 days later for lungworm counts and measurements of length to be made. At both times group 1 calves were found to be largely resistant to reinfection; group 2 were slightly more susceptible although the differences from group 1 were not statistically significant. Group 3 calves were more susceptible with no significant difference in worm counts from naive infection controls.

Animal Husbandry↗
PubMed1997

Efficacy of moxidectin, ivermectin and albendazole oral drenches for suppression of periparturient rise in ewe worm egg output and reduction of anthelmintic treatment for lambs.

Sixty multiparous crossbred ewes which had lambed within three days in the first week of April 1996, were divided into four groups. Each group consisted of 15 ewes plus 12 pairs of twins and three single lambs. Group 1 was left untreated, group 2 was treated with albendazole 2.5 per cent drench, group 3 received moxidectin 0.1 per cent drench and group 4 received ivermectin 0.08 per cent drench. The ewes in each group were dosed with their anthelmintic on April 4 (day 0) before being turned out to separate equal-sized paddocks within the same field on the following morning. The field had been used for grazing sheep annually for many years and was considered to be contaminated with infective larvae of the common gastrointestinal nematodes infecting sheep in the region. Faecal samples were collected every two weeks from the ewes and lambs until July 25 (day 112). The lambs in each group were dosed with the anthelmintic used for their dams on day 42, and the dose was repeated when more than 50 per cent of the lambs in any group had a faecal egg count of more than 200 eggs per gram (epg). The total faecal egg output of the treated ewes over days 14 to 70, compared with that of the untreated control group, was reduced by 78.9 per cent by the moxidectin drench, by 47.6 per cent by ivermectin, and by 21.5 per cent by albendazole. The lambs in the groups treated with moxidectin and ivermectin required only one treatment on day 42 before reaching finishing weight; those in the albendazole-treated group were treated twice and the control group once. The faecal egg outputs of the lambs from day 42 until the end of the experiment on day 112 were reduced by 75 per cent by the moxidectin drench, by 48.5 per cent by ivermectin, and by 9 per cent by albendazole. There were no significant differences between the rates of weight change of either ewes or lambs in any of the groups.

Albendazole↗
PubMed1997

The C-terminal domain of tissue inhibitor of metalloproteinases-2 is required for cell binding but not for antimetalloproteinase activity.

We have generated a C-terminally-truncated form of recombinant tissue inhibitor of metalloproteinases-2 (designated rTIMP-2 delta) in which the region of the inhibitor extending from residue 128 to 194 and including 3 of the 6 disulfide bonds is deleted. rTIMP-2 and rTIMP-2 delta had similar inhibitory activities toward interstitial collagenase and inhibited the activation of the precursor form of matrix metalloproteinase-2 (proMMP-2). rTIMP-2 also bound with high affinity (Kd 0.99 nM) to HT1080 human fibrosarcoma cells treated with 12-O-tetradecanoyl-phorbol-13-acetate. However deletion of the C-terminal domain of TIMP-2 significantly lowered the cell surface binding affinity, with competition experiments indicating a 2 order of magnitude difference between rTIMP-2 and rTIMP-2 delta in the concentrations needed to displace 125I-labeled rTIMP-2 binding. These data indicate that the C-terminal domain of TIMP-2 is not required for the antimetalloproteinase activity but plays a major role in the high affinity cell surface binding of the inhibitor.

Animals↗
PubMed1997

Biologically active conformer of the effector region of human C5a and modulatory effects of N-terminal receptor binding determinants on activity.

A conformationally biased decapeptide agonist of human C5a (C5a55-74Y65,F67,P69,P71,D-Ala73 or YSFKPMPLaR) was used as a functional probe of the C5a receptor (C5aR) in order to understand the conformational features in the C-terminal effector region of C5a that are important for C5aR binding and signal transduction. YSFKPMPLaR was a potent, full agonist of C5a, but at higher concentrations had a superefficacious effect compared to the natural factor. The maximal efficacy of this analogue was 216 +/- 56% that of C5a in stimulating the release of beta-glucuronidase from human neutrophils. C5aR activation and binding curves both occurred in the same concentration range with YSFKPMPLaR, characteristics not observed with natural C5a or more conformationally flexible C-terminal agonists. YSFKPMPLaR was then used as a C-terminal effector template onto which was synthesized various C5aR binding determinants from the N-terminal core domain of the natural factor. In general, the presence of N-terminal binding determinants had little effect on either potency or binding affinity when the C-terminal effector region was presented to the C5aR in this biologically active conformation. However, one peptide, C5a12-20-Ahx-YSFKPMPLaR, expressed a 100-fold increase in affinity for the neutrophil C5aR and a 6-fold increase in potency relative to YSFKPMPLaR. These analyses showed that the peptides used in this study have up to 25% of the potency of C5a in human fetal artery and up to 5% of the activity of C5a in the PMN enzyme release assay.

Antigens, CD↗
PubMed1997

Molecular adjuvant effects of a conformationally biased agonist of human C5a anaphylatoxin.

A conformationally biased decapeptide agonist of human C5a anaphylatoxin (YSFKPMPLaR) was used as a molecular adjuvant in stimulating Ab responses against peptide epitopes derived from human MUC1 glycoprotein and the human mu and kappa opioid receptors. C57BL6 mice were immunized with the MUC1 epitope (YKQGGFLGL); the C5a agonist (YSFKPMPLaR); YSFKPMPLaR and YKQGGFLGL together, but unconjugated; a C5a-active, MUC1 epitope construct (YKQGGFLGLYSFKPMPLaR); and a C5a-inactive, reversed moiety construct (YSFKPMPLaRYKQGGFLGL). High Ab titers specific for the MUC1 epitope were observed only in mice immunized with the C5a-active epitope construct. Similar results were obtained in BALB/c mice immunized with the C5a-active, MUC1 epitope construct. Abs from the sera of the C57BL6 mice were predominately of the IgG2a, IgG2b, and IgM isotypes and were reactive against human recombinant MUC1 and MUC1 expressed by the Panc-1 M1F.15 pancreatic cell line. When compared with the corresponding KLH-epitope conjugates in C57BL6 mice, the epitope-C5a agonist constructs produced titers of specific IgG Abs of isotypes distinct from those generated by the keyhole limpet hemocyanin-epitope conjugates. Rabbits immunized with a mu opioid receptor epitope-C5a agonist construct (GDLSDPCGNRTNLGGRDSLYSFKPMPLaR) or a kappa opioid receptor epitope-C5a agonist construct (FPGWAEPDSNGSEDAQLYSFKPMPLaR) generated high titer, epitope-specific Ab responses. Ab titers generated in response to the opioid epitope-C5a agonist constructs were comparable to those generated by the opioid KLH-epitope conjugates. The results of this study are discussed in terms of possible mechanisms by which the conformationally biased C5a agonist serves as a molecular adjuvant.

Adjuvants, Immunologic↗
PubMed1997

Superficial femoral artery eversion endarterectomy: a useful adjunct for infrainguinal bypass in the presence of limited autogenous vein.

PURPOSE: To evaluate, in a group of technically high-risk patients, the results of infrainguinal revascularization using a conduit constructed with endarterectomized superficial femoral artery (SFA) and available arm or saphenous vein. METHODS: Of 237 consecutive lower extremity vein graft bypass procedures performed in 195 patients from July 1992 through August 1996, 15 SFA eversion endarterectomies (in 10 men and five women; median age, 70 years) were performed and used as a composite bypass conduit with available autogenous vein for the treatment of limb-threatening ischemia. In each case, an occluded SFA was divided 8 to 15 cm distal to its origin, proximally endarterectomized, and sewn end-to-end to a segment of vein to provide adequate conduit length for bypass grafting. Indications for this technique were unavailability of vein as a result of failed previous bypass grafting (n = 10) or previous coronary artery bypass grafting (n = 5). Veins were sewn distally to a below-knee popliteal artery (n = 4; 27%) or tibial artery (n = 11; 73%). RESULTS: Primary patency, secondary patency, and limb salvage rates at 36 months by life table analyses for the 237 grafts were 62.3%, 81.0%, and 77.2%, respectively. The 15 composite SFA-vein bypass grafts had 36-month primary patency, secondary patency, and limb salvage rates of 60.0%, 72.0%, and 65.9%, respectively (mean follow-up, 15 months). Currently, eight of these patients (53%) have patent bypass grafts; two (13%) died at 4 and 18 months after the operation with patent grafts; two (13%) underwent amputations for progressive foot gangrene despite a patent bypass graft; and three (20%) had grafts that thrombosed at 4, 5, and 10 months. Typical hyperplastic intrinsic graft-threatening stenoses developed in two patients (13%) in the SFA segment at 4 and 8 months; they were discovered by routine duplex scan surveillance. CONCLUSION: Composite SFA eversion endarterectomy/vein graft conduits yield acceptable results, behave similarly to other autogenous conduits used for technically high-risk infrainguinal revascularization, and are beneficial when autogenous vein is limited.

Aged↗
PubMed1997

Ultrasound-guided compression for the treatment of iatrogenic femoral pseudoaneurysms.

To assess the emerging use of ultrasound-guided compression (USGC) to treat iatrogenic femoral artery pseudoaneurysm (PA), we reviewed the experience in the accredited vascular laboratory of a large community teaching hospital from June 1993 to August 1994. Femoral duplex ultrasonography was done on 94 consecutive patients suspected of having PA. Twenty-eight PAs were found in 27 patients (14 women and 13 men; mean age, 62 years). Causes included cardiac angiography (n = 9), coronary angioplasty (n = 4), coronary stent placement (n = 12), and peripheral angioplasty (n = 3). Aneurysms were identified 1 to 90 days (median, 6 days) after femoral procedures, and their size ranged from 0.9 cm to 8.0 cm (mean, 2.5 cm). Fifteen patients (53%) were receiving systemic anticoagulation, 7 (25%) had spontaneous resolution, 10 (36%) were treated by femoral stitch arteriorrhaphy, and 11 (39%) were treated by USGC. Compression included vascular surgery standby, identification of PA neck (channel to native artery), 10-minute compression intervals to obliterate flow with a 5 MHz duplex ultrasound probe, and restudy at 24 hours. This protocol resulted in successful thrombosis in 8 patients (73%) but failed in 3 patients (37%), who required operative repair. Large aneurysm size, PA neck size, and systemic anticoagulation did not influence successful compression of PAs. Advanced age of the PA and operator inexperience were factors believed to negatively influence success. These data suggest that USGC is safe and effective and causes less morbidity than traditional repair, and it has emerged as the initial treatment of choice for iatrogenic femoral pseudoaneurysms.

Aneurysm, False↗
PubMed1997

A comparison of serum ionized calcium concentrations and serum total calcium concentrations in dogs with lymphoma.

Serum ionized calcium and total calcium concentrations were measured in 16 dogs with lymphoma and 49 healthy control dogs. Blood samples for all determinations of ionized calcium were collected into tubes containing silicone separator gel and processed under a closed anaerobic system. An ionized calcium analyser with ion selective electrodes was used to determine pH, ionized calcium and ionized calcium adjusted to pH 7.4. Reference ranges for ionized calcium (iCa pH 7.4) of 1.30-1.46 mmol/l, and for total calcium of 2.37-2.82 mmol/l were established. A stronger correlation (r = 0.85) was found between measured ionized calcium and total calcium levels in dogs with lymphoma and hypercalcaemia than in those with lymphoma and normocalcaemia (r = 0.64). Measurement of serum ionized calcium was diagnostically concordant with the measurement of serum total calcium in the determination of calcium status in all dogs with lymphoma. Serum ionized calcium did not provide a diagnostic advantage over total calcium in the detection of hypercalcaemia of malignancy in these dogs.

Animals↗
PubMed1997

Dual diagnosis patients in the modified therapeutic community: does a criminal history hinder adjustment to treatment?

The efficacy of the drug-free therapeutic community (TC) in treating patients with chemical dependence and in rehabilitating persons with criminal histories has been extensively studied and is well established since the late 1960's. More recently, this format has been modified in order to treat individuals suffering from both addictive disorders and chronic, severe mental illness. In an indigent inner-city population, this latter group includes many patients who also have significant histories of criminal behavior. To date, there have been no systematic attempts to assess the impact of a history of criminality on the course of treatment of these patients, as they might be thought less adaptable to the milieu of a TC. In the current study, data from a sample of homeless male MICA patients were analyzed to determine if those patients with a history of criminal convictions were as likely as non-criminal patients to adjust effectively to the social milieu of a modified drug-free therapeutic community. Of 183 sequential admissions studied, 76 had never been convicted of a crime, 46 had 1 conviction, and 61 had 2 or more. No differences were observed between the groups with respect to length of stay, social adjustment on admission, and change in social adjustment during the first two months of treatment. These findings suggest that a history of criminal conduct does not compromise a dually diagnosed patient's likelihood of engaging in the social contract necessary for successful treatment in a TC.

Adult↗