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Objectives. To evaluate beneficial effects of postmenopausal hormone replacement therapy (HRT) on endothelial function, measured as intraplatelet cyclic guanosine monophosphate (cGMP, mediator of nitric oxide), cyclic adenosine monophosphate (cAMP, mediator of prostacyclin) and plasma endothelin-1 (ET-1), and on monocyte activation, measured as plasma neopterin. Design. Part 1: double-blind randomized trial for 3 months; part 2: open study for 9 months. Setting. The study was performed at the Department of Endocrinology, University Hospital, Malmo, Sweden. Subjects. Fifty-one postmenopausal women participated in part 1 and 46 in part 2. Inclusion criteria included a history of amenorrhoea for at least 6 months before the study and body mass index ≥ 24 kg m-2 Intervention. Randomization for either placebo (n = 24) or HRT (n = 27). HRT was given as 2 mg oestradiol valerate for the first 3 months with the addition of 10 mg medroxyprogesterone for 10 days every third month thereafter. Measurements. Performed at baseline and after 3 and 12 months of the study. Results. In the HRT group, intraplatelet cGMP increased from 0.56 (0.35-0.94) to 0.61 (0.423.40) and 0.65 (0.43-1.08) pmol (109 platelets)-1 after 3 and 12 months, respectively (P = 0.01), whereas plasma ET-1 decreased from 3.2 (1.1.-6.8) to 2.0 (0.8-5.1) and 1.8 (0.4-15.4) pg mL-1 (P < 0.001). Intraplatelet cAMP and plasma neopterin were unchanged. When smokers (n = 15) and non-smokers (n = 12) in the HRT group were analysed separately, significant effects were seen only amongst smokers. The control group showed unchanged levels of cGMP, cAMP, ET-1 and neopterin. Conclusions. These data suggest beneficial effects of HRT on endothelial function which may account for anti-atherogenic effects of HRT in postmenopausal women, especially in smokers. No effects of HRT were seen upon monocyte activation.

Leukocyte-derived inflammatory mediators and endothelial production of vasoconstrictive factors, such as endothelin-1, and vasodilatory and platelet anti-aggregatory factors, such as nitric oxide (NO) and prostacyclin (PGI2), may have a role in the pathogenesis of atherosclerosis. In this study we evaluated whether insulin affects the monocyte-derived inflammatory mediator neopterin and endothelin- in plasma (p), and NO and PGI2 mediators cyclic 3'-5' guanosine monophosphate (cGMP) and cyclic 3'-5' adenosine monophosphate (cAMP) in platelets. P-neopterin was measured by enzyme linked immunosorbent assay (ELISA), and p-endothelin-1, intraplatelet cAMP and cGMP were measured by radioimmunoassay (RIA) before and after euglycaemic hyperinsulinaemic clamping in 51 healthy postmenopausal women aged 53-54 years. "Placebo clamping" with NaCl infusion was performed in a subgroup of 5/51 women. During euglycaemic hyperinsulinaemic clamping, p-endothelin-1 decreased (from 3.3+/-0.2 pg/ml to 2.4+/-0.2 pg/ml; p

Release of inflammatory mediators from leukocytes and endothelial release of vasoactive factors are both important in the pathogenesis of atherosclerosis. To evaluate the concen trations of a specific marker for macrophage activation, neopterin, and the potent endothelial derived vasoconstrictive peptide endothelin-1 (ET-1), during the acute and chronic stages of cerebral ischemia, plasma concentrations of neopterin and ET-1 were measured in 59 patients with acute cerebral infarction or transient ischemic attack (median age 73 years, range 43-93, 27 men) and after a 1-year follow-up in 57/59 (97%) of patients. Plasma neopterin was higher at follow-up (6.3 nmol/L [3.7-21.6] vs 5.6 nmol/L [3.5-17.2]; p < 0.05) than at the acute stage, whereas the plasma ET-1 concen tration was unchanged. Plasma concentrations of both neopterin and ET-1 correlated directly with age both in the acute stage ( r = 0.42 and r = 0.35, respectively; p < 0.01) and after follow-up ( r = 0.34; p < 0.05 and r = 0.27; p = 0.05, respectively). In conclusion, plasma neopterin increased after acute cerebral ischemia, indicating chronic inflammatory activity and continuous macrophage activation in ischemic cerebrovascular diseases.

To clarify relationships between the (endothelial vasodilatory and vasoconstrictive function) and leukocyte inflammatory mediators in subjects with asymptomatic athero sclerosis, we measured (intraplatelet cyclic 3-5 ¢ guanosine monophosphate [cGMP] and cyclic 3-5 ¢ adenosine monophosphate [cAMP]), plasma endothelin (ET-1), and plasma neopterin in 197 subjects with asymptomatic atherosclerosis (median age 63 years, range 49-69 years). We measured neutrophil protease 4 (NP 4), tumor necrosis factor (TNFμ), soluble tumor necrosis factor receptor-1 (sTNFR-1), and neutrophil gelatinase associ ated lipocalin (NGAL) in 152 of the 197 subjects. Intraplatelet cGMP correlated inversely with plasma ET-1 (r=-0.22; p=0.01), which confirms earlier in vitro data of the inhibitory effect of ET-1 on NO production and/or the cGMP mediated inhibitory effect of NO on ET-1 production. Plasma neopterin as well as NP4 correlated directly with intraplatelet cGMP (r=0.24; p

Inflammatory mediators secreted by activated leukocytes play a role in the pathogenesis of atherosclerosis. They may also affect the production of vasodilatory and platelet antiaggregatory factors such as nitric oxide (NO) and prostacyclin (PGI2) from the vascular endothelium. Production of NO and PGI2, the effecs of which are mediated by cyclic 3′,5′-guanosine monophosphate (cGMP) and cyclic 3′,5′-adenosine monophosphate (cAMP), respectively, is disturbed in atherosclerosis, whereas increased NO levels have been found in acute cerebral ischemia. To investigate leukocyte activation and its possible influence upon endothelial function in cerebral ischemia we measured plasma neutrophil gelatinase-associated lipocalin (NGAL) and soluble tumor necrosis factor receptor protein-1 (sTNFR-1) by ELISA, and intraplatelet cAMP and cGMP by radioimmunoassay in 59 patients with acute ischemic stroke or transient ischemic attack (mean age 71 years, 27 males) and after a 1-year follow-up in 57/59 (97%) patients. NGAL (152 ± 58 vs. 126 ± 48 µg/l), sTNFR-1 (3.50 ± 2.2 vs. 2.59 ± 1.31 µg/l), and cAMP (5.12 ± 1.71 vs. 4.06 ± 0.92 pmol/109 platelets) were higher (p < 0.001) after follow-up than in acute cerebral ischemia. At follow-up sTNFR-1 and cGMP partially correlated (r = 0.31; p < 0.05), controlling for age and platelet count. In conclusion, plasma NGAL and sTNFR-1 and intraplatelet AMP increase after acute cerebral ischemia, indicating chronic inflammatory activity and endothelial activation. Plasma sTNFR-1 levels are related to intraplatelet cGMP levels.

This retrospective study evaluated long-term effects of percutaneous transluminal renal angioplasty (PTRA) in atherosclerotic renal artery stenosis (ARAS), and predictors of benefit on blood pressure (BP).During 1997-2003, 234 patients (age 69+/-11 years, 138 [59%] males) underwent PTRA for ARAS at Malmö Vascular Centre. Cure was defined as diastolic (D)BP90 mmHg and systolic (S)BP140 mmHg off antihypertensive medication. Improvement was defined as DBP90 mmHg and/or SBP140 mmHg on the same or reduced number of medications, or reduction in DBP ofor=15 mmHg with the same or reduced number of medications. Benefit was defined as cure or improvement.After PTRA, SBP and DBP decreased (P0.001), and remained lower (P0.001) until last follow-up after 4.1+/-3.3 years. Antihypertensive medication decreased (P0.001), and remained lower at one month (P0.001), one year (P0.01), and last follow-up (P0.05). Renal function was unchanged until last follow-up, when it deteriorated (P0.001). Patients showing benefit of PTRA on BP at last follow-up (N.=150 [64%]) used more antihypertensive drugs before PTRA (P=0.012), especially angiotensin converting enzyme inhibitors (ACEi) or angiotensin II receptor blockers (ARBs) (P=0.010), and diuretics (P=0.015). In logistic regression, use of ACEi or ARBs failed to reach significancy (P=0.054). Patients dying during follow up (N.=100 [43%]) showed higher age (P0.0001) and s-creatinine (P0.0001), lower glomerular filtration rate (P0.0001), and higher frequency of diabetes mellitus (P0.005). In logistic regression only age (P=0.009) and diabetes mellitus (P=0.014) predicted mortality.We confirmed beneficial effects on BP with PTRA in ARAS. ACEi, ARB and diuretic treatment before PTRA predict favourable long-term BP-response in univariate analysis.

The physical activity pattern among 43 subjects (25 women, 18 men) from the Intervention Study of Elderly in Gothenburg (IVEG) has been evaluated by means of heart rate monitoring, rating of perceived exertion and recording activities over a 30-hour period. These subjects had previously been interviewed about their activity pattern, including the duration of their daily walks. In 91% of the participants the average heart rate was below 100 beats/min during walking. Considerable individual variations were noted in the duration of domestic activities and of walks. Using heart rate levels equal to or above the average heart rate during walking as a criterion, it was found that 68% of the women, but only 17% of the men, spent more time on domestic activities than on walking. Nonetheless, it is suggested that in addition to walking, domestic activities, owing to their duration, are important in maintaining physical fitness in the elderly, especially among women. This should be taken into account when physical activity is being classified (to avoid bias in favour of men). A modified version of a previously published six-grade scale for the classification of physical activity has been suggested. (Aging 2:191–198,1990)

This observational study was undertaken in order to analyse whether any differences could be detected between diabetic and non-diabetic patients with critical limb ischemia (CLI) concerning the inflammatory response.A total number of 259 consecutive patients with CLI were treated between October 2001 and January 2003.Among the 259 patients, 135 (52%) had diabetes, previously known in 123, and detected during hospitalization in 12. The diabetic patients more often showed gangrene (P0.05) and infra-inguinal atherosclerosis (84% vs 67%, P=0.001). The patients with diabetes showed a better lipid profile (total cholesterol 4.6 vs 5 mmol/L, P=0.006 and lower LDL-cholesterol (2.7 vs 3.1 mmol/L, P=0.010) despite the same frequency of statin treatment. They showed a higher creatinine (149 vs 117 micromol/L, P=0.0003) than the non-diabetic patients. Of the inflammatory markers, C-reactive protein (CRP) was equally elevated in both groups. Tumor necrosis factor-a (TNF-a) was increased among the diabetic patients (2.6 vs 1.8 pg/mL, P0.05), and this difference was most evident in those with gangrene. Neopterin was also higher among the diabetic patients (31 vs 21 mmol/L, P0.01), but CD40L was not different between groups.Diabetes mellitus was very common in CLI patients, and more often combined with renal impairment and infra-inguinal atherosclerosis. The inflammatory markers TNF-a and neopterin were elevated in patients with diabetes as compared to non-diabetic patients, but this difference cannot explain why CLI is 10 times more frequent in diabetic patients.

The epidemiology of critical limb ischemia (CLI) is insufficiently studied, and treatment of risk factors for atherosclerosis has received less attention in CLI patients than in patients with coronary or precerebral atherosclerosis. The aim of this study was to establish the incidence of CLI and the quality of risk factor treatment in Swedish CLI patients.During 14 months, 316 consecutive CLI patients were referred to the Malmo Department of Vascular Diseases. Two hundred and fifty-nine (82%) consented to evaluation of intercurrent disease, medication, ankle and arm blood pressures (BP), plasma glucose and lipid levels, p-homocysteine, cardiolipin antibodies and activated protein C (APC)-resistance.The incidence of CLI was 38/100,000 inhabitants/year. Patient age was 75 +/- 10 years, and BP 147 +/- 26/75 +/- 14 mmHg. Systolic or diastolic BP above recommended levels (140/90 mmHg) occurred in 137 (53%) patients. P-cholesterol was 4.8+/-1.2 mMol/L, but cholesterol above recommended level (5 mMol/L) or LDL above recommended level (3 mMol/L) occurred in 125 (48%) patients. Only 24% of patients met national recommendations for both BP and lipid levels. Diabetes mellitus was previously known in 123 (47%) patients, and another 12 (5%) patients showed diabetic fasting glucose levels during the hospital stay. Eighty-four (32%) patients were active, and 72 (28%) were former smokers. Myocardial infarction or angina pectoris had previously been diagnosed in 123 (47%) patients. P-homocysteine was 17 +/- 7 _mol/l, cardiolipin antibodies occurred in 71 (27%) and APC-resistance in 34 (13%) patients.Patients with CLI show high comorbidity in vascular diseases and high prevalence of modifiable risk factors for atherosclerotic vascular disease. The use of evidence-based medical therapy is suboptimal in this high-risk group.

Antiplatelet therapy in order to reduce the platelet aggregability is widely used to prevent recurrent stroke events. Data from several studies indicates that the inter-individual variation concerning the ability of standard doses of aspirin to inhibit platelet aggregation is substantial. The rationale of the present study was to test whether platelet aggregation in whole blood was enhanced in subjects that had suffered an ischemic stroke event under aspirin treatment.Two groups of patients were included: 1) patients that have suffered 1 stroke event and were thereafter under continuous treatment with aspirin 75-160 mg once daily (n=17); 2) patients that have suffered at least 2 stroke events, and aspirin 75-160 mg was prescribed after the 1(st) event (n=17). Platelet aggregation was tested in whole blood with collagen (5 microg/mL and 1 microg/mL), ADP (5 microMol/L) and arachidonic acid (0.5 microg/mL). Aggregation was recorded as change in impedance and release of ATP after the addition of a luciferin-luciferase reagent.The inhibitory effect of aspirin tested with arachidonic acid as an agonist was complete in all the tested subjects. Aggregation induced by ADP 5 microMol/L was significantly higher in the subjects with recurrent stroke compared to those with a single stroke, when tested as impedance change. ATP release with ADP as an agonist was the same in both groups.The present study gives some indication that differences in ADP-induced aggregation, with a higher remaining aggregating ability after ASA treatment, might be of importance for the risk of stroke recurrence.

Hyperhomocysteinemia is a risk factor for atherosclerosis and venous thrombosis, probably exerting its effects through endothelial function. Homocysteine levels are lowered by folate supplementation, and such treatment improves endothelial function. However, whether folate supplementation decreases vascular risk and improves survival is unknown. The aim of this study was to evaluate endothelial function and mononuclear leukocyte inflammatory activity during homocysteine lowering in patients with hyperhomocysteinemia and vascular disease.Endothelial function assessed as plasma (p-)endothelin(ET)-1 and intraplatelet cGMP and cAMP, and mononuclear leukocyte inflammatory activity, assessed as p-neopterin were studied during homocysteine lowering in 50 patients with hyperhomocysteinemia and vascular disease, randomized to folate supplementation or no treatment for 3 months.P-homocysteine decreased during the 3 months not only in patients on folate supplementation (from 27 [21-52] to 14 [8-41] micromol/l; p0.001), but also in the untreated group (from 23 [20-35] to 19 [4-31] micromol/l; p0.001). P-ET-1 decreased during folate supplementation (from 5.7 [2.7-11.6] to 4.1 [1.8-9.0] pg/ml; p0.01), but was unchanged in the untreated group 4.1 [2.0-9.5] pg/ml and 4.5 [2.7-7.1] pg/ml). P-neopterin was unchanged in patients on folate supplementation (9.7 [5.1-54.4] and 7.6 [5.7-73.0] nmol/l), but increased in the untreated group (from 8.2 [4.7-19.5] to 8.6 [4.6-24.6] nmol/l; p0.05). Intraplatelet cGMP decreased in patients on folate supplementation (from 0.86 [0.21-2.00] platelets to 0.56 [0.17-1.42] pmol/10(9) platelets; p0.05), but was unchanged in the untreated group. No significant differences concerning intraplatelet cAMP occurred in either group.Folate supplementation in hyperhomocysteinemia is associated with decreasing levels of both ET-1 and intraplatelet cGMP, and the absence of an increase in the levels of the inflammatory mediator neopterin.

The relationships between abdominal and pelvic fat compartments and glucose and lipid metabolism were investigated in early postmenopausal women. Fifty-five healthy, postmenopausal women aged 52-53 yr participated in the study. Fat distribution (intra-abdominal and sc abdominal fat, and intrapelvic and sc pelvic fat) was estimated by computed tomography. Insulin sensitivity was assessed by euglycemic hyperinsulinemic clamp. In a multiple regression analysis, the size of the intra-abdominal fat compartment was the only significant predictor of insulin sensitivity (r(2) = 24%; P = 0.0002). Plasma triglycerides were closely related to the size of the intra-abdominal fat compartment (r(2) = 26%; P0.0001), whereas plasma free fatty acid concentrations only correlated to the size of the sc abdominal fat compartment (r(2) = 18.5%, P = 0.001). In early postmenopausal women the amount of the intra-abdominal fat strongly influences insulin sensitivity and plasma triglyceride levels, whereas plasma free fatty acids are closely related to the amount of the sc abdominal fat. Accordingly, from a metabolic standpoint it seems most essential to reduce intra-abdominal fat in postmenopausal women.

Lipid-lowering statin treatment reduces cardiovascular morbidity and mortality and improves endothelial function in patients with hypercholesterolemia. The aim of the present study was to evaluate plasma levels of fibrinogen, factor VII, and the macrophage-derived inflammatory mediator neopterin during lipid lowering. In addition, the endothelial production of platelet antiaggregatory and vasodilatory factors such as nitric oxide and prostacyclin, and vasoconstrictive factors such as endothelin-1, was assessed. Plasma fibrinogen, factor VII, endothelin-1, and the neopterin and intraplatelet nitric oxide and prostacyclin mediators cyclic 3'-5'guanosine monophosphate (cGMP) and cyclic 3'-5'adenosine monophosphate (cAMP) were measured before and 6 months after the institution of treatment with fluvastatin in 17 patients (eight men and nine women, median age 60 years) with vascular disease and previously untreated hypercholesterolemia. After 6 months, a decrease of 1.62 mmol/l [1.26-2.18 (19%); P < 0.01] was noted in levels of total cholesterol, and a decrease of 1.70 mmol/l [1.52-2.30 (28%); P < 0.01] in levels of low-density lipoprotein cholesterol. Plasma levels of fibrinogen had increased [from 4.81 g/l (4.26- 5.27) to 5.17 g/l (4.81-5.67); P < 0.05], whereas no significant changes had occurred in intraplatelet levels of cGMP [decrease by 0.05 pmol/109 platelets (-0.17 to 0.24); NS], cAMP [decrease by 0.13 pmol/109 platelets (- 0.37 to 0.86); NS], plasma endothelin-1 [decrease by 0.05 pg/ml (-0.60 to 0.70); NS], plasma factor VII [from 1.14 IE/ml (0.58-1.38) to 1.22 IE/ml (0.96-1.46); NS], or plasma neopterin [from 8.6 nmol/l (7.1-11.5) to 8.7 nmol/l (7.9-11.3); NS]. In conclusion, during cholesterol-lowering treatment with fluvastatin, plasma levels of fibrinogen increased whereas intraplatelet cyclic nucleotide levels and plasma endothelin-1, factor VII and neopterin levels were unchanged. (Less)

To assess whether uncomplicated deep vein thrombosis could be treated in an out-patient setting without increasing the frequency of complications, and to determine the proportion of patients with deep vein thrombosis, traditionally treated as in-patients at the Departments of Medicine, who are eligible for such treatment.In a multicentre study, carried out at six hospitals of varying sizes and serving a population of about 600,000, consecutive patients over 18 years of age, with verified deep vein thrombosis, primarily presented as acute cases at the respective Departments of Medicine, were considered for treatment on an out-patient basis during a 1-year period.Those eligible for out-patient treatment were put on low molecular weight heparin and oral anticoagulants, and scheduled for daily attendance at the out-patient clinic of the respective Dept. of Medicine. Details of any complication were recorded according to a standard check-list. The patients underwent a full checkup at three-month follow-up.Any bleeding event or pulmonary embolism. Progress of thrombosis.Of 523 patients considered for out-patient treatment, 126 (24%) were excluded according to the defined exclusion criteria, 197 (38%) were treated entirely on an out-patient basis, and another 43 (8%) were initially treated in hospital (median two days) before being transferred to the out-patient setting. Three patients had to be hospitalized for suspected complications, but none of these turned out to be serious. No serious bleeding event or thromboembolic complication was registered.Uncomplicated acute deep vein thrombosis could be safely treated on an out-patients basis. At least 50% of the patients with this diagnosis, former treated as in-patients at the Depts. of Medicine, are eligible for such treatment.

Nitric oxide (NO) exerts its vasodilator and antiaggregatory effects through activation of soluble guanylate cyclase and the consequent increase in the concentration of cGMP in target cells. We conducted this study in order to evaluate relationships between intraplatelet cGMP levels and risk factors for atherosclerosis in middle aged subjects. Intraplatelet cGMP was determined by radioimmunoassay and related to age, BMI, blood pressure, antihypertensive treatment, total, LDL and HDL cholesterol, triglycerides, blood glucose, HbA1c, smoking habit and intimal thickness of the common carotid artery in 265 subjects participating in a health survey (age 59 +/- 6 years, range 48-68 years, 121 females, 144 males). Intraplatelet cGMP concentration was inversely correlated with total serum cholesterol (r = -0.18; p0.01) and HDL cholesterol (r = -0.14, p0.05) as well as with platelet count (r = -0.29; p0.001). When platelet count was adjusted for, only the correlation between total serum cholesterol and cGMP remained significant. No significant correlations could be demonstrated between intraplatelet cGMP levels and measurable parameters of atherosclerosis. Lower levels of the vasodilating and antiaggregating mediator cGMP in platelets are related to higher levels of serum total cholesterol. These results favour the hypothesis of a relationship between lipid levels and NO associated vasodilator and antiaggregating function in atherosclerosis.

A case of tongue necrosis in a patient with temporal arteritis who was taking ergotamine is described, and the role of ergotamine tartrate in provoking the tongue necrosis is considered. The literature on this unusual complication is critically reviewed, and the value of a carotid angiography in assessing the tongue ischaemia is exemplified.

Long-term effects on insulin sensitivity and leucocyte sodium transport were studied in 42 glucose-intolerant hypertensives on beta-blockers, randomly assigned to continuous beta-blockade (beta group) or a switch to captopril treatment (mean daily dose 69.1 mg) (ACE group). In the ACE group, despite a tendency towards improvement, glucose uptake during the euglycaemic insulin clamp procedure did not change significantly from the baseline value of 4.0(0.5-12.9) mg/kg/min, values at 6 and 12 months being 4.8(1.3-14.7) and 4.4(1.5-9.8) mg/kg/min, respectively: the corresponding values for the beta group were 4.2(1.1-15.3), 3.6(1.2-8.9) and 4.0(1.5-12.0) mg/kg/min. The 22Na efflux rate constant, both baseline and follow-up values, was similar in both groups, and unrelated to insulin sensitivity. Owing to the surprisingly great variation in peripheral glucose uptake, the subgroup with values below the median for the population as a whole (4.9 mg/kg/min) was evaluated separately: those switched to captopril treatment manifested a 60% improvement in glucose disposal at 6 months and persisting at 12 months, the respective values being 2.1(0.5-4.8) (baseline), 3.5(1.3-6.3) and 3.4(1.5-6.1) mg/kg/min, (P = 0.012). The body mass index (BMI) was not significantly affected. Values for BMI, peripheral insulin and triglycerides were higher in the subgroup with glucose disposal below the median than in the subgroup with values above the median. Correlation between BMI and glucose uptake was highly significant (r = -0.75, P = 0.0001). The present findings suggest that captopril may be a better alternative than beta-blockers for treating the highly insulin-resistant, glucose-intolerant patients, predominantly to be found among the overweight.

The concentrations of verapamil and norverapamil have been measured in milk and plasma samples from a 32 year-old woman treated with verapamil 80 mg tds while breast-feeding her child. The average steady-state concentrations of verapamil and noverapamil in milk were, respectively, 60% and 16% of the concentrations in plasma. The breast-fed child received less than 0.01% of the dose of verapamil given to the mother. No verapamil or norverapamil (less than 1 ng/ml) could be detected in the plasma from the child.

Passage of the cardioselective beta adrenoceptor antagonists atenolol and metoprolol from serum to breast milk was assessed in 7 lactating women treated with atenolol due to hypertension developing during pregnancy, and in 3 healthy women who agreed to take metoprolol at cessation of lactation. For both drugs, the concentration in breast milk was higher than that in serum at every time studied, and the resulting AUC values were 1.5–6.8 times (atenolol) and 2.6–3.7 times (metoprolol) greater in milk than in serum. Assuming ingestion of 75 ml milk per meal, and as the maximum milk concentrations recorded were 6.35 µmol/l (atenolol) and 2.58 µmol/l (metoprolol), the data indicate that the dose following a meal at the time of maximum maternal drug concentration would not exceed 0.13 mg atenolol and 0.05 mg metoprolol, and would be considerably less after the other meals. In the only infant from whom serum samples could be obtained, the plasma atenolol concentration ranged between 0 and 0.26 µmol/l. None of the atenolol-exposed infants had any sign of an effect of the beta blocker. It would seem likely that, unless renal (atenolol) or hepatic (metoprolol) function in the infant were pronouncedly impaired, breast feeding need not be interrupted due to maternal medication with ordinary doses of either of these drugs. However, the infants should be observed for signs of beta blockade.

The risk for a smoker of developing cancer of the larynx depends on the activity of the enzyme arylhydroxcarbonhydroxylase in his cells. The higher the genetically determined arylhydroxcarbonhydroxylase activity, the higher is the probability of developing the disease.

Smoking habits, dental status and aryl-hydrocarbonhydroxylase (AHH) inducibility were studied in a series of 52 oral leucoplakias and 20 oral cancers. There was an obvious association between leucoplakia, cancer and smoking. A significant overrepresentation of high AHH and a corresponding underrepresentation of low AHH inducibility were found among the smokers with leucoplakia and in the oral carcinoma group. In both groups, however, the dental status was largely normal.

Low sodium and potassium adenosine triphosphatase (ATPase) activity has been proposed as a mechanism behind diabetic neuropathy. In this study the platelet ATPase activity and platelet noradrenaline efflux rate were determined in 47 insulin-dependent diabetes mellitus (IDDM) patients and 20 controls. Ulnar motor conduction velocities, tested in a subgroup, were lower in patients than in controls (52.7 +/- 1.3 m s-1 vs. 61.3 +/- 1.4 m s-1; P less than 0.001). Platelet ATPase activity tended to be increased in the patients compared with the controls (29.9 +/- 1.0 x 10(-3) min-1 vs. 26.9 +/- 1.1 x 10(-3) min-1; NS). In ulnar nerve function tested subjects, ATPase activity was higher in patients than in controls (31.2 +/- 1.7 x 10(-3) min-3 vs. 25.9 +/- 1.3 x 10(-3) min-1; P less than 0.01). The platelet noradrenaline efflux rate tended to be higher in patients with lower brake indices, a sign of autonomic neuropathy, than in controls (29.0 +/- 3.0 x 10(-3) min-1 vs. 21.2 +/- 0.9 x 10(-3) min-1; P less than 0.05). The platelet ATPase activity was not decreased in IDDM patients, however, a connection between diabetic autonomic neuropathy and platelet transmittor leakage was indicated.