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J Friend

Publications and source records attributed to J Friend.

At least 19 recordsLinked to original sources
PubMed2001

Cost effectiveness of computer tailored and non-tailored smoking cessation letters in general practice: randomised controlled trial.

OBJECTIVES: To develop and evaluate, in a primary care setting, a computerised system for generating tailored letters about smoking cessation. DESIGN: Randomised controlled trial. SETTING: Six general practices in Aberdeen, Scotland. PARTICIPANTS: 2553 smokers aged 17 to 65. INTERVENTIONS: All participants received a questionnaire asking about their smoking. Participants subsequently received either a computer tailored or a non-tailored, standard letter on smoking cessation, or no letter. MAIN OUTCOME MEASURES: Prevalence of validated abstinence at six months; change in intention to stop smoking in the next six months. RESULTS: The validated cessation rate at six months was 3.5% (30/857) (95% confidence interval 2.3% to 4.7%) for the tailored letter group, 4.4% (37/846) (3.0% to 5.8%) for the non-tailored letter group, and 2.6% (22/850) (1.5% to 3.7%) for the control (no letter) group. After adjustment for significant covariates, the cessation rate was 66% greater (-4% to 186%; P=0.07) in the non-tailored letter group than that in the no letter group. Among participants who smoked <20 cigarettes per day, the cessation rate in the non-tailored letter group was 87% greater (0% to 246%; P=0.05) than that in the no letter group. Among heavy smokers who did not quit, a 76% higher rate of positive shift in "stage of change" (intention to quit within a particular period of time) was seen compared with those who received no letter (11% to 180%; P=0.02). The increase in cost for each additional quitter in the non-tailored letter group compared with the no letter group was pound 89. CONCLUSIONS: In a large general practice, a brief non-tailored letter effectively increased cessation rates among smokers. A tailored letter was not effective in increasing cessation rates but promoted shift in movement towards cessation ("stage of change") in heavy smokers. As a pragmatic tool to encourage cessation of smoking, a mass mailing of non-tailored letters from general practices is more cost effective than computer tailored letters or no letters.

Adolescent↗
PubMed2001

Long-term nutrient intake and early age-related nuclear lens opacities.

OBJECTIVE: To assess the relation between usual nutrient intake and subsequently diagnosed age-related nuclear lens opacities. SUBJECTS: Four hundred seventy-eight nondiabetic women aged 53 to 73 years from the Boston, Mass, area without previously diagnosed cataracts sampled from the Nurses' Health Study cohort. METHODS: Usual nutrient intake was calculated as the average intake from 5 food frequency questionnaires that were collected during a 13- to 15-year period before the evaluation of lens opacities. The duration of vitamin supplement use was determined from 7 questionnaires collected during this same period. We defined nuclear opacities as a nuclear opalescence grade of 2.5 or higher using the Lens Opacification Classification System III. RESULTS: The prevalence of nuclear opacification was significantly lower in the highest nutrient intake quintile category relative to the lowest quintile category for vitamin C (P<.001), vitamin E (P =.02), riboflavin (P =.005), folate (P =.009), beta-carotene (P =.04), and lutein/zeaxanthin (P =.03). After adjustment for other nutrients, only vitamin C intake remained significantly associated (P =.003 for trend) with the prevalence of nuclear opacities. The prevalence of nuclear opacities was significantly lower (P<.001) in the highest vitamin C intake quintile category relative to the lowest quintile category (odds ratio, 0.31; 95% confidence interval, 0.16-0.58). There were also statistically significant trends of decreasing prevalence of nuclear opacities with increasing duration of use of vitamin C (P =.004 for trend), vitamin E (P =.03 for trend), and multivitamin (P =.04 for trend) supplements, but only duration of vitamin C supplement use remained significantly associated with nuclear opacities after mutual adjustment for use of vitamin E (P =.05 for trend) or multivitamin (P =.02 for trend) supplements. The prevalence of nuclear opacities was significantly lower (P =.004) for women who used a vitamin C supplement for 10 or more years relative to women who never used vitamin C supplements (odds ratio, 0.36; 95% confidence interval, 0.18-0.72). Plasma measures of vitamins C and E taken at the eye examination were also inversely associated with the prevalence of nuclear opacities. CONCLUSION: These results provide additional evidence that antioxidant nutrients play a role in the prevention of age-related nuclear lens opacities.

Aged↗
PubMed2000

The biosynthesis of oxylipins of linoleic and arachidonic acids by the sewage fungus Leptomitus lacteus, including the identification of 8R-Hydroxy-9Z,12Z-octadecadienoic acid.

When the sewage fungus Leptomitus lacteus was grown in liquid culture aerobically and then transferred to medium containing long-chain fatty acids, it produced a number of oxygenated fatty acids. From linoleic acid (18:2n-6), the major metabolite produced was R-8-hydroxy-9Z,12Z-octadecadienoic acid (8R-HODE), with additional quantities of 8,11-di-HODE, 11,16-di-HODE, and 11,17-di-HODE. Other fatty acid derivatives identified included 7-HODE, 10-HODE, and 13-hydroxy-octadecamonoenoic acid. Arachidonic acid (20:4n-6) was metabolized primarily to 18- and 19-hydroxy-eicosatetraenoic acids (18- and 19-HETE) also as R enantiomers, along with smaller quantities of 17-HETE, 9-HETE, 14,15-dihydroxy-eicosatrienoic acid and 11,12,19-trihydroxy-eicosatrienoic acid. The oxygenated products of long-chain fatty acids, in particular the biosynthesis of 8R-HODE, a compound classified as a precocious sporulation inducer, were similar to those produced by an unrelated fungal species in the Ascomycota, the take-all fungus Gaeumannomyces graminis. As in G. graminis, the biotransformation of linoleate to 8R-HODE was not significantly inhibited by exposure of the organism to CO. This indicated that the enzyme responsible for 8R-HODE biosynthesis in Leptomitus could be similar to that of G. graminis; yet we did not detect 7,8-di-HODE as a product of 18:2n-6 metabolism as in G. graminis. CO did inhibit the biosynthesis of 14,15-di-HETE, 18-HETE, and 19-HETE in L. lacteus, which suggested the involvement of a cytochrome P450-type monooxygenase. The biosynthesis of 8R-HODE from 18:2n-6 was found to occur in certain cell lysates, specifically in low speed (15,000 x g) supernatant, following cell disruption.

Arachidonic Acid↗
PubMed2000

Evidence for the mitochondrial biosynthesis of 3R-hydroxy-5Z,8Z,11Z,1 4Z-eicosatetraenoic acid in the yeast Dipodascopsis uninucleata.

The biosynthesis of 3R-hydroxy-5Z, 8Z, 11Z,14Z-eicosatetraenoic acid (3R-HETE) from arachidonic acid (20:4n-6) by the hyphal-forming yeast, Dipodascopsis uninucleata, in cell-free enzyme extracts required CoASH, ATP, NAD+ and Mg2+; 3R-HETE was present as the CoA derivative in enzyme extracts and its biosynthesis was associated with mitochondria. Its synthesis was high from arachidonoyl-CoA (15% conversion of the substrate; 22 nmol mg protein(-1) x h), but significantly higher from trans-2-arachidonoyl-CoA (53 nmol mg protein(-1) x min). Aspirin, an inhibitor of prostaglandin endoperoxide synthase synthase (cyclooxygenase), did not significantly inhibit 3R-HETE biosynthesis in enzyme extracts, as opposed to antimycin A (46% inhibition). The chirality of 3-HETE was 95% R and 5% S. 3R-HETE has the same chirality as the products of peroxisomal enoyl-CoA hydratases of Neurospora crassa and Saccharomyces cerevisiae; the difference appears to be that in D. uninucleata the Renantiomers are synthesized in mitochondria. Exogenously supplied eicosapentaenoic acid was converted to 3-hydroxy 5Z,11Z,14Z,17Z-eicosapentaenoic acid by cell-free enzyme extracts though there was no requirement for a 5Z,8Z-diene structure for the biosynthesis of 3-hydroxylated fatty acids as 3-hydroxy-8Z,11Z,14Z, and 3-hydroxy-11Z,14Z,17Z-eicosatrienoic acids were synthesized from the corresponding fatty acids. We found no evidence for the synthesis of the prostaglandins F2alpha and E2.

Culture Media↗
PubMed2000

Are women with polycystic ovary syndrome resistant to activated protein C?

OBJECTIVE: This study was performed to test the hypothesis that an increased prevalence of activated protein C (APC) resistance in women with polycystic ovary syndrome (PCOS) puts them at increased risk of miscarriage and thrombosis. DESIGN: Case control study. SETTING: A district general hospital in the United Kingdom. PATIENT(S): Forty-one women with PCOS and 25 controls. INTERVENTION(S): Clinical histories, ultrasound scans, and venepunctures. MAIN OUTCOME MEASURE(S): Diagnosis of PCOS or control, clinical histories, APC resistance according to an activated partial thromboplastin time-based assay. RESULT(S): There was no significant difference in the proportion of women with APC resistance in both groups (three women in the PCOS group [7%] vs. one woman in the control group [4%]). The prevalence of APC resistance in the entire study population was 6.5%. In the PCOS group, 29% (12/41) gave a positive family history of thrombosis compared with 8% (2/25) in the control group. None of the women with a positive family history of thrombosis had abnormal antithrombin 111, protein C, or protein S levels. CONCLUSION(S): This study suggests that women with PCOS may have the same prevalence of APC resistance as the background population and that APC resistance may not put them at a higher risk of thrombosis or miscarriage compared with the case of the general population.

Abortion, Spontaneous↗
PubMed2000

Raised plasminogen activator inhibitor-1 (PAI-1) is not an independent risk factor in the polycystic ovary syndrome (PCOS).

BACKGROUND: It has been postulated that an insulin-driven increase in plasminogen activator inhibitor-1 (PAI-1) levels may link insulin resistance to anovulatory infertility in women with PCOS and that it may place them at increased risk of thromboembolic disease. However, previous studies have been conflicting because many have failed to control for body mass index (BMI) which may affect PAI-1. The aim of this study was to investigate PAI-1 activity in women with PCOS and to compare it with unaffected controls of a similar BMI. DESIGN AND PATIENTS: 41 women with PCOS and 25 weight-matched controls participated in this cross-sectional study. Patients were evaluated clinically and by pelvic ultrasound and fasting blood samples were taken for haematological and biochemical tests. MEASUREMENTS: PAI-1 activity, insulin, glucose, triglycerides, total cholesterol, LDL cholesterol, HDL cholesterol, FSH, LH, PRL, testosterone, SHBG, 17-hydroxyprogesterone, plasminogen, fibrinogen (alpha2 antiplasmin, blood pressure and insulin sensitivity with a homeostasis model assessment (HOMA) computer programme. RESULTS: There was no significant difference in BMI or in (log) PAI-1 activity in women with PCOS compared with controls (BMI 29.5 +/- 5.6 vs. 28.4 +/- 6.3 kg/m2, P = 0.25 and PAI-1 2.56 (SD 0.85) vs. 2.14 (SD 0.98) au/ml, P = 0.07). The median fasting insulin level was significantly higher (17 (4.6-134.5) vs. 9.6 (3.7-41.5) mU/l, P < 0.01), and insulin sensitivity significantly lower in the PCOS group, ( 43.17% (5. 48-160) vs. 82.8% (21.8-193), P < 0.01). Women with PCOS also had a significantly higher free androgen index, LH/FSH ratio and a lower HDL/total cholesterol ratio. However blood pressure and all other lipid and haematological measurements were not significantly different between both groups. There were significant positive correlations between (log) PAI-1 activity and BMI (rho = 0.61), triglycerides (rho = 0.49) and fasting insulin (rho = 0.60) and a negative correlation with HDL cholesterol (rho = - 0.46). Triglyceride concentrations showed the most significant relationship with (log) PAI-1 activity on multiple regression. 29% of PCO women (12/41) gave a positive family history of thrombosis compared to 8% (2/25) in the control group. CONCLUSION: Plasminogen activator inhibitor-1 activity is not raised in women with PCOS independent of obesity and these results do not support the hypothesis that it may contribute to their anovulatory infertility, or increase their risk of thrombosis. The only significant metabolic features of the PCOS independent of obesity are insulin resistance, hyperinsulinaemia and lower HDL/total cholesterol ratio. The higher frequency of a positive family history of thrombosis in these women nevertheless requires further explanation.

Adult↗
PubMed2000

Immunohistochemical detection of plasminogen activator inhibitor-1 in polycystic ovaries.

Anovulation in women with polycystic ovary syndrome (PCOS) is incompletely understood. The concentration of the glycoprotein plasminogen activator inhibitor-1 (PAI-1) is raised in insulin resistance. This has been described in the granulosa and theca cell layers of the animal but not the human ovary. This study was performed to investigate the location of PAI-1 in the human ovary and investigate whether it may contribute to anovulation in PCOS. PAI-1 was localized immunohistochemically and quantitated using computer image analysis in 17 ovarian follicles from five women with a diagnosis of PCOS and compared with 15 follicles from six normal ovaries. PAI-1 was predominantly found in the granulosa and theca cells in both polycystic and normal ovaries. Image analysis did not reveal a difference in the PAI-1 signal from polycystic compared with normal ovaries. This study shows that PAI-1 plays a role in human ovulation, but its role in PCOS requires further research.

Adolescent↗
PubMed1999

Bronchial hyperresponsiveness and adult onset wheeze: the influence of atopy.

The commonly held belief that adult onset wheezing illness is primarily nonatopic in nature suggests that the role of atopy in the pathophysiology of bronchial hyperresponsiveness (BHR) in adult onset wheeze may be minimal. This study examined risk factors for BHR (BHR: provocative dose causing a 20% fall in forced expiratory volume in one second PD20 < or =16.38 micromol methacholine) among 82 subjects with adult onset wheeze and among 191 subjects who had never wheezed. Subjects were identified from a cohort of subjects aged 39-45 yrs who were known to have had no childhood wheeze and who were involved in a 30 yr follow-up survey. Risk factors for BHR were examined among all subjects with BHR and among subjects with BHR stratified according to whether or not they had ever wheezed. The prevalence of BHR was 40% (33/82) among the subjects with adult onset wheeze and 11% (21/191) among the subjects who had never wheezed. Lower baseline lung function (odds ratio (OR) = 0.94; 95% confidence interval (CI) = 0.92-0.97 per unit forced expiratory volume (FEV1)% predicted) and atopy (OR = 7.23; CI = 2.53-20.64 for all three measures of atopic compared to nonatopic) were associated with BHR, while smoking and family history showed no statistically significant relation to BHR. This pattern was also apparent in analyses stratified by symptom status. A family history of atopy increased the risk that BHR was accompanied by wheezing symptoms (OR = 4.75; CI = 1.53-14.72 for more than one affected relative compared to no affected relatives). These findings suggest that atopy is associated with bronchial hyperresponsiveness in adults known to have had no childhood wheeze. A familial factor reflecting genetic influences and/or shared environmental factors may influence whether bronchial hyperresponsiveness is associated with symptoms.

Adolescent↗
PubMed1999

Lens autofluorescence and light scatter in relation to the lens opacities classification system, LOCS III.

PURPOSE: To compare values of the human lens autofluorescence and back light scatter measurements with the improved Lens Opacities Classification System, LOCS III. METHODS: We measured autofluorescence and back light scatter of the lens from 122 smoking males aged 57 to 76 years who participated in a cancer prevention study. The retroillumination and slit-lamp photographs of the lenses were graded according to LOCS III by the Center for Ophthalmic Research in Boston. Lens fluorometry was carried out with a previously described technique using blue-green (495 nm/520 nm) autofluorescence range. Interzeag Lens Opacity Meter 701 was used for light scatter measurements. RESULTS: LOCS III nuclear opalescence and color grades were statistically significantly correlated with lens autofluorescence as well as with light scatter values. The lens transmission index of autofluorescence measurements showed the highest correlation with the nuclear color (r = -0.71; p < 0.0001) and the light scatter value with nuclear opalescence (r = 0.64; p < 0.0001). There was no correlation between autofluorescence measurements and LOCS III grades of cortical or posterior subcapsular cataract. A weak relation could be found between the grades of cortical cataract and light scatter values. CONCLUSIONS: The lens fluorometry provides a practical clinical technique to evaluate the yellow coloration and opalescence of the human lens nucleus. It may be a useful additional tool together with a subjective grading system in the follow-up of optical changes occurring in the nuclear region of the lens.

Aged↗
PubMed1998

Risk factors for nuclear opalescence in a longitudinal study. LSC Group. Longitudinal Study of Cataract.

This study evaluated risk factors for increases in nuclear opacification of the lens in the Longitudinal Study of Cataract (1989-1993; Boston, Massachusetts), which included 764 participants. Baseline data on demographic, medical, and other risk factors were available from an earlier case-control study; follow-up visits were completed yearly over a 4-year period. The lens photographs taken at baseline and at each follow-up visit were graded using the Lens Opacities Classification System III protocol. Analyses evaluated which risk factors collected at baseline were related to increased nuclear opacification at follow-up. The MULCOX2 method, an extension of Cox regression for nested event-time data, was used to estimate the effects of the risk factors. This method accounted for the correlation between fellow eyes. Results showed that the risk of nuclear opacification increased with each year of age (relative risk (RR) = 1.07), white race (RR = 2.94), lower education (RR = 1.50), use of gout medications (RR = 2.32), current smoking (RR = 1.58), family history of cataract (RR = 1.39), and preexisting posterior subcapsular opacities (RR = 6.67). An association with early use of eyeglasses was also suggested (RR = 1.37). In conclusion, nuclear opacification was related to demographic and other variables, including potentially modifiable factors such as current smoking and use of gout medications. Most risk factors identified by this longitudinal study confirm those found by the original case-control study. The increased risk of nuclear opacities in whites appears to be a new finding.

Adult↗
PubMed1998

Antioxidant vitamins and nuclear opacities: the longitudinal study of cataract.

OBJECTIVE: The association of antioxidant nutrients and risk of nuclear opacification was evaluated in the Longitudinal Study of Cataract. DESIGN: Nutritional data were collected at baseline on the 764 participants, which included assessment of dietary intake, use of vitamin supplements, and plasma levels of vitamin E. Ophthalmologic and other data were collected at baseline and at yearly follow-up visits, including lens photographs, which were graded using the Lens Opacities Classification System III protocol. MAIN OUTCOME MEASURES: Analyses examined whether the nutritional factors at baseline were related to increases in nuclear opacification at follow-up. The MULCOX2 approach, an extension of the Cox regression model, was used. Results are presented as relative risks (RRs) and 95% confidence intervals. INTERVENTION: Intervention was not applicable. RESULTS: The risk of nuclear opacification at follow-up was decreased in regular users of multivitamin supplements (RR = 0.69; 0.48-0.99), vitamin E supplements (RR = 0.43; 0.19-0.99), and in persons with higher plasma levels of vitamin E (RR = 0.58; 0.36-0.94). CONCLUSIONS: In regular users of multivitamin supplements, the risk of nuclear opacification was reduced by one third; in regular users of vitamin E supplements and persons with higher plasma levels of vitamin E, the risk was reduced by approximately half. These results are similar to those obtained in our earlier case-control study. Because these data are based on observational studies only, the results are suggestive but inconclusive. The possible effect of nutritional supplements on the lens requires confirmation by ongoing clinical trials.

Adult↗
PubMed1997

Effects of NMDA and its antagonists on ventral horn cholinergic neurons in organotypic roller tube spinal cord cultures.

Neurotoxic effects of excitatory amino acid (EAA) receptor agonist N-methyl-D-aspartic acid (NMDA) and its antagonists on ventral horn cholinergic neurons were studied in organotypic rollertube cultures of spinal cord (OTC-SCs) using biochemical assays of choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) activity, and AChE histochemistry. NMDA exposure decreased ChAT and AChE activity by 83% and 66%, respectively. Cultures treated with NMDA also showed a marked loss of AChE staining in both dorsal and ventral horns and a significant, dose-dependent decrease in the number of ventral horn AChE-positive neurons (VHANs). NMDA treatment primarily resulted in the loss of small VHANs (< 300 microns2). VHANs with a size and distribution typical of alpha-motoneurons were relatively well preserved. The effects of NMDA on OTC-SCs appeared to be independent of the age of the cultures. The NMDA antagonist DL-AP5 completely prevented the NMDA-induced loss of ChAT activity, but only attenuated the effect of NMDA on ChE activity. The antagonists DL-AP5, D-AP5 and MK-801, used alone, caused significant loss and/or shrinkage of VHANs. These effects appeared to be distinct from the NMDA mediated toxicity. The results indicate that NMDA and its antagonists exert powerful toxic effects on ventral horn cholinergic neurons. The large cholinergic alpha-motoneurons, however, appear to be relatively immune to these toxic effects.

Acetylcholinesterase↗
PubMed1997

Incidence and progression of cortical and posterior subcapsular opacities: the Longitudinal Study of Cataract. The LSC Group.

OBJECTIVE: The purpose of the study is to estimate incidence and progression rates of cortical and posterior subcapsular (PSC) opacities in the Longitudinal Study of Cataract (LSC). DESIGN: An epidemiologic study of the natural history of lens opacities in a clinic-based population. PARTICIPANTS: The LSC was based on 764 participants in an earlier case-control study of lens opacities. MAIN OUTCOME MEASURES: Baseline data, collected until 1988, included color slit and retroillumination photographs. The same data were collected at follow-up visits from 1989 to 1993. The Lens Opacities Classification System III (LOCS III) was used to assess lens changes between baseline and follow-up photographs. The product-limit method was used to estimate the incidence and progression rates. RESULTS: After 5 years of follow-up, the incidence rates for developing cortical and PSC opacities were 7.7% and 4.3%, respectively. The progression rate of pre-existing cortical opacities was 16.2% after 5 years, and was twice as high as the incidence rate. The progression of pre-existing PSC opacities was much higher, and reached 55.1% after 5 years of follow-up. The incidence of newly developed cortical or PSC opacities increased with age. The incidence of PSC opacities also increased when coexisting opacities were present at baseline. CONCLUSIONS: After 5 years, 1 in every 13 patients developed new cortical opacities, and 1 in 24 developed new PSC opacities. The 5-year progression rates for cortical and PSC opacities were much higher than the incidence rates. These results can be used to estimate the rate of cortical and PSC changes in similar populations.

Aged↗
PubMed1996

Incidence and progression of nuclear opacities in the Longitudinal Study of Cataract.

PURPOSE: To estimate incidence and progression rates of nuclear opacities in the Longitudinal Study of Cataract, an epidemiologic study of the natural history of all types of lens opacities. METHODS: The Lens Opacities Classification System III was used to assess longitudinal changes between baseline and follow-up lens photographs for the 764 Longitudinal Study of Cataract participants. Baseline data, collected until December 1988 as part of a case-control study, included color slit, retroillumination, and Scheimpflug photographs. The same data were collected by the longitudinal Study of Cataract at four subsequent visits at yearly intervals. RESULTS: Among patients free of nuclear opacities at baseline, the incidence of new opacities was 6% after 2 years and 8% after 5 years of follow-up. The progression of pre-existing nuclear opacities was much higher. After 2 years, nuclear opacities had progressed in more than one third of the patients with pre-existing opacities; after 5 years, almost half had progressed. Older age was significantly related to higher incidence of new nuclear opacities, but not to progression of pre-existing opacities. Patients with other opacity types had higher nuclear incidence and progression rates. CONCLUSIONS: In this clinic-based, older-patient population, new nuclear opacities developed in less than one tenth of the patients after 5 years of follow-up. In contrast, almost one half of the patients with pre-existing opacities had worsened after 5 years. These estimated rates can be used to plan intervention or other studies of nuclear changes in similar populations.

Aged↗
PubMed1996

The pattern of glomerular disease in New Caledonia: preliminary findings.

Two hundred and two renal biopsies from 181 patients in New Caledonia were classified into either primary glomerulonephritis or glomerulopathy associated with systemic disease. These were then compared with 670 similar biopsies from 634 in-patients at Sydney's Royal Prince Alfred Hospital (RPAH). The most prevalent primary glomerular disease among the New Caledonian cases was focal segmental glomerulosclerosis, compared with IgA disease among the RPAH cases. Mesangiocapillary glomerulonephritis, post-infectious glomerulonephritis and minimal lesion nephropathy were all relatively commoner among the New Caledonian biopsies, but the numbers were small. The most prevalent systemic glomerulopathy in the New Caledonian cases were amyloidosis. This was the least common among our RPAH group. Diabetes mellitus and lupus nephritis were also slightly more common in the New Caledonian group. Focal necrotizing/crescentic glomerulonephritis was unusual in the New Caledonian samples, while it was the most common systemic glomerulopathy among the RPAH group.

Europe↗