bluuebunny/crossref_metadata_2025_split huggingface dataset:
Private channel: a single unusual compound assures specific pollinator attraction in Ficus semicordata
Authors: Chen Chun , Song Qishi , Proffit Magali , Bessière Jean‐Marie , Li Zongbo , Hossaert‐McKey Martine 
Published: August 2009

Summary 1. Floral scents have been suggested to play a key role in the obligate pollination mutualism between figs and fig wasps. However, few studies have determined whether pollinator‐attractive compounds could alone assure species‐specificity (‘private channel’), or whether specificity is mediated by more complex ‘floral filters’, of which scent is only one component. 2. We examined changes in the floral volatile compounds of Ficus semicordata, a dioecious fig species, during and after pollination using headspace collection and compound identification by Gas Chromatography/Mass Spectrometry (GC/MS). One benzenoid compound, 4‐methylanisole, was strongly predominant (94–98%) among the volatile compounds emitted by both male and female receptive figs of F. semicordata, whereas it was totally absent in the volatiles emitted by figs 4 days after pollination, as well as in receptive‐stage volatiles emitted by two other sympatric fig species, Ficus racemosa and Ficus hispida. 3. Bioassays using the specific pollinator of F. semicordata, Ceratosolen gravelyi, in a Y‐tube olfactometer showed that 4‐methylanisole was attractive to C. gravelyi in a wide range of concentrations (from 1·22 × 10−2 ng/100 μL to 1·22 × 106ng/100μL). Moreover, chemical blends lacking 4‐methylanisole were unattractive to C. gravelyi. These non‐active odour sources included volatile compounds emitted by receptive figs of the two other sympatric fig species and volatiles of F. semicordata post‐pollination figs. 4. All these results suggest that 4‐methylanisole is the main signal compound in the floral scent of F. semicordata that attracts its obligate pollinator to the host figs at the precise stage required for pollination and oviposition. Furthermore, the high proportion of 4‐methylanisole in the odours of receptive figs of both sexes was consistent with the hypothesis of chemical mimicry in dioecious figs. 5. A simple signal comprised of one compound that is unusual among Ficus and that is an infrequent, usually minor, component of other floral odours, may thus function as a private channel in this specialized obligate mutualism.
Response of recruitment to light availability across a tropical lowland rain forest community
Authors: Rüger Nadja , Huth Andreas , Hubbell Stephen P. , Condit Richard 
Published: August 2009

Summary1. Many hypotheses about species coexistence involve differential resource use and trade‐offs in species’ life‐history traits. Quantifying resource use across most species in diverse communities, although, has seldom been attempted.2. We use a hierarchical Bayesian approach to quantify the light dependence of recruitment in 263 woody species in a 50‐ha long‐term forest census plot in Panama. Data on sapling recruitment were obtained using the 1985–1990 and 1990–1995 census intervals. Available light was estimated for each recruit from yearly censuses of canopy density.3. We use a power function (linear log–log relationship) to model the light effect on recruitment. Different responses of recruitment to light are expressed by the light effect parameterb. The distribution ofbhad a central mode at 0.8, suggesting that recruitment of many species responds nearly linearly to increasing light.4. Nearly every species showed increases in recruitment with increasing light. Just nine species (3%) had recruitment declining with light, while 198 species (75%) showed increasing recruitment in both census intervals. Most of the increases in recruitment were decelerating, i.e. the increase was less at higher light (b < 1). In the remaining species, the response to light varied between census intervals (24 species) or species did not have recruits in both intervals (41 species).5. Synthesis.Nearly all species regenerate better in higher light, and recruitment responses to light are spread along a continuum ranging from modest increase with light to a rather strict requirement for high light. These results support the hypothesis that spatio‐temporal variation in light availability may contribute to the diversity of tropical tree species by providing opportunities for niche differentiation with respect to light requirements for regeneration.
Smoking induces insulin resistance—a potential link with the insulin resistance syndrome
Authors: ATTVALL S. , FOWELIN J. , LAGER I. , VON SCHENCK H. , SMITH U. 
Published: August 2009

Abstract. Objectives. The acute effect of smoking and snuffing on insulin sensitivity was studied in a group of healthy habitual smokers.Design The euglycaemic clamp technique was combined with the subcutaneous injection of a bolus (0.1 U kg−1) of fast‐acting insulin (Actrapid®). Randomized subjects smoked either one cigarette per hour for 6 h, took one bag‐packed snuff per hour for 6 h or refrained from nicotine for 48 h before as well as during the clamp.Subjects. Seven healthy smokers, four females and three males, of normal weight (BMI, mean ± SKM. 21 ± 0.7 kg m−2 with a range of 18.6–23.9), aged 31 ± 2 years (range 24–35 years), who had consumed at least 20 cigarettes per day for at least 5 years were studied. They were recruited through an advertisement in a newspaper. Results. The steady‐state plasma nicotine levels were similar during smoking and snuffing. The insulin and glucose levels were also similar during all three clamps. Smoking, but not snuffing, impaired insulin action (P < 0.05) mainly due to a lower peripheral glucose uptake. The mean growth hormone levels during the 6‐h study were more than doubled during smoking (P < 0.01) while no significant differences were seen in the other counter‐regulatory hormones.Conclusion. Smoking (also in habitual smokers) acutely impairs insulin action and leads to insulin resistance. Thus, smoking can be of importance for the development of the insulin resistance syndrome associated with risk for cardiovascular disease.
Effect of coffee on ambulatory blood pressure in patients with treated hypertension
Authors: EGGERTSEN R. , ANDREASSON Å. , HEDNER T. , KARLBERG B. E. , HANSSON L. 
Published: August 2009

Abstract. Effects of caffeine on ambulatory blood pressure, heart rate, renin‐angiotensin system, and ANP were studied in patients treated for mild to moderate hypertension in a randomized, double‐blind, placebo‐controlled, cross‐over trial comparing 2 weeks of caffeine‐free diet with 2 weeks of regular coffee use. Twenty‐three patients (13 men; aged 28–74 years) with treated, mild to moderate essential hypertension and a regular intake of 3–4 cups of coffee daily completed the study.Mean 24‐h, day‐ or night‐time ambulatory blood pressure and heart rate were not different between regimens. Nor were there any effects on the renin‐angiotensin system while ANP was significantly increased during caffeine intake. Compliance of the dietary regimen was excellent as assessed by serum caffeine concentration measurements. We conclude that habitual coffee drinking did not influence the 24‐h blood pressure profiles or cardiovascular hormones in treated hypertensives.
The predictability of risk factors with respect to incidence and mortality of myocardial infarction and total mortality. A 12‐year follow‐up of the Oslo Study, Norway
Authors: HÅHEIM L. LUND , HOLME I. , HJERMANN I. , LEREN P. 
Published: August 2009

Abstract.Objectives. To study the prognostic value of several risk factors on incidence and mortality of myocardial infarction (MI) and total mortality in men.Design. Prospective cohort study of 12 years' follow‐up.Setting. All men in Oslo aged 40–49 and a 7% sample of men aged 20–39 were invited for screening.Subjects. Of all 30025 invited men, of whom 25015 were aged 40–49, a total of 16209 men aged 40–49 attended the screening and risk factors were recorded for these men.Main outcome measures. Incidence of first MI (nonfatal and fatal), mortality of MI, total mortality.Results. When examining the rate ratio of the fifth to the first quintile of risk factors we found that systolic and diastolic blood pressures were stronger predictors for mortality than incidence of MI. The rate ratios (95% confidence interval) of systolic blood pressure were 3.73 (2.56, 5.44) and 2.56 (2.01, 3.25) respectively. For diastolic blood pressure the corresponding rate ratios were 4.14 (2.84, 6.04) and 2.78 (2.18, 3.54). Small differences in the rate ratios for these end‐points were found for total serum cholesterol and triglycerides. Daily cigarette smoking versus non‐cigarette smoking was a stronger predictor for MI mortality than incidence, with rate ratios of 3.16 (2.45, 4.24) and 2.34 (2.00, 2.79) respectively. The Cox proportional hazards regression analysis confirmed the above results.Conclusions. Total serum cholesterol and triglycerides predicted incidence and mortality of MI equally well. Whereas blood pressure and daily cigarette smoking predicted mortality of MI more strongly.
Captopril does not acutely enhance insulin sensitivity
Authors: HELVE E. , TUOMINEN J. A. , KOIVISTO V. A. 
Published: August 2009

Abstract. Objectives. To examine the acute effects of captopril administration on insulin sensitivity in normotensive type 1 diabetic patients.Design. An euglycaemic insulin clamp (150 min) was performed in a randomized order twice in each subject: once with the oral administration of captopril (25 mg), once with placebo, both given in the beginning of the insulin infusion.Setting. The study was performed at the clinical research laboratory of Helsinki University Hospital, Second and Third Departments of Medicine.Subjects. We studied seven male, normotensive type 1 diabetic patients with normal body weight, duration of diabetes 15 ± 2 years, HbA, 9.8 ± 0.7% and daily insulin dose 47 ± 4 units. In addition, nine matched healthy control subjects were examined.Results. During placebo administration glucose disposal rate in the diabetic patients was not significantly different from that in the control subjects. Captopril administration reduced blood pressure in both groups, whereas glucose disposal rate did not change significantly in diabetic or control subjects. When diabetic and control subjects were analysed together, captopril decreased glucose disposal by 9% (P < 0.05).Conclusions. Acute captopril administration does not improve insulin sensitivity in normotensive type 1 diabetic patients or control subjects.
Lower tocopherol serum levels in subjects with abdominal adiposity
Authors: ÖHRVALL M. , TENGBLAD S. , VESSBY B. 
Published: August 2009

Abstract. Objectives. Peroxidation of lipoproteins may be of critical importance in the development of atherosclerosis. Tocopherol is considered to be the most effective lipid‐soluble antioxidant. The main aim of this study was to measure the serum tocopherol concentrations in a Swedish reference population and to relate them to family history, lifestyle and serum lipoprotein composition.Design. A health survey of risk factors for coronary heart disease was carried out among the employees of a Swedish company.Subjects. Ninety per cent (906) of the employees participated.Results. Mean alpha, beta and gamma tocopherol levels corrected for lipids were 1.57 (SD 0.24), 0.04 (SD 0.01) and 0.20 (SD 0.07) μg ml−1, respectively. Alpha tocopherol levels were slightly higher in women than in men, but there was no difference between different ages. Smokers had a lower alpha tocopherol level than non‐smokers (1.54 and 1.59 μg ml−1; P = 0.03) and persons with low physical activity had a lower level than those with high activity (1.53 and 1.62 μg ml−1, respectively; P = 0.002). Alpha tocopherol concentration was inversely correlated to abdominal sagittal diameter (r = –0.24, P = 0.0001).Conclusions. The average tocopherol concentrations in this Swedish population were higher than in countries with a high incidence of coronary heart disease but similar to those in countries with a similar, intermediate incidence. The inverse correlation to abdominal adiposity may partly explain why this adiposity is a risk factor for coronary heart disease.
Clinical index to predict bacteraemia caused by staphylococci
Authors: LEIBOVICI L. , GRANSDEN W. R. , EYKYN S. J. , KONSIBERGER H. , DRUCKER M. , PITLIK S. D. , PHILLIPS I. 
Published: August 2009

Abstract. Objectives. To define risk factors associated with bacteraemia caused by Staphylococcus aureus or coagulase‐negative staphylococci; and to use them to define patients in need of empiric anti‐staphylococcal antibiotic treatment.Design, Derivation set: observational, prospective study; validation set: retrospective analysis of a prospectively collected database.Setting. Derivation set: Beilinson Medical Centre, Petah Tiqva, Israel—a 900‐bed university hospital. Validation set: St Thomas's Hospital, London, UK—an 800‐bed teaching hospital.Subjects. All episodes of bacteraemia detected at Beilinson Medical Centre between March 1988 and September 1990 (derivation set, n = 1410), and at St Thomas's Hospital during 1987–1990 (validation set, n = 1040).Interventions. None.Main outcome measures. Percentage of staphylococcal bacteraemia in groups of patients defined by the models.Results. The following factors were associated with Staphylococcus aureus bacteraemia: focus of infection (whether high or low risk), haemodialysis, intravenous drug abuse and infection acquired in the orthopaedic ward. A logistic model was used to divide the derivation set into three groups with percentages of Staphylococcus aureus bacteraemia of 1.8%, 13.2% and 33.7% (P < 0.0001); and the validation group 2.5%, 18.2% and 53.2% (P < 0.0001). Factors associated with coagulase‐negative staphylococcal bacteraemia were: central or peripheral intravenous catheter as the focus of infection, a preterm neonate, the presence of a central intravenous catheter, low temperature, and a low white blood cell count. A second model including those factors was used to divide the derivation set into three groups with percentages of coagulase‐negative staphylococcal bacteraemia of 1.9%, 22.8%, and 43% (P < 0.0001). In the validation set, the percentages were 2.9%, 22.4% and 31.0% (P < 0.001).Conclusions. The present study defines groups at high risk for staphylococcal bloodstream infection, in which empiric treatment should include an anti‐staphylococcal drug.
Drug expectations and drug choices of hospital physicians
Authors: DENIG P. , HAAIJER‐RUSKAMP F. M. , WESSELING H. , VERSLUIS A. 
Published: August 2009

Abstract. Objectives. To assess whether differences in drug choices of hospital physicians are related to differences in the underlying decision‐making process.Design. A survey study was conducted addressing drug choices in six therapeutic fields with existing interprescriber variations; prescribers and non‐prescribers of drugs of which the merits were not sufficiently proven (i.e. the ‘target drugs’) were compared.Setting. A 1000‐bed university hospital in The Netherlands.Subjects. All 85 hospital physicians working in specialities involving one of the selected fields were asked to participate; 72 physicians completed the interviews.Main outcome measures. Comparisons were made regarding three elements of the decision‐making process: (1) the physicians' expectations of the target drugs and frequently used alternatives, (2) the weights attached to the principal treatment aspects, and (3) the extent to which their actual choice is based on these expectations and weights.Results. In three fields, i.e. anti‐emetics, vasodilators, and platelet inhibitors, the prescribers of the less desirable target drugs had higher expectations of these drugs in comparison to the non‐prescribers. In the other therapeutic fields, choosing target drugs was related either to attaching less importance to side‐effects and costs, or to attaching less importance to reports from clinical trials. Twenty of the 46 treatment choices of the prescribers of target drugs could not be predicted from their expressed views as opposed to 5 of the 36 choices of the non‐prescribers (P < 0.05).Conclusions. Choosing less desirable drugs is not always related to having too high expectations of the drug. Assigning a different importance to certain aspects of the drug and resorting to decision strategies that do not include the weighing of all pros and cons provide alternative explanations for such treatment choices.
Glucocorticoid‐induced osteoporosis: pathogenesis, prevention and treatment, with special regard to the rheumatic diseases
Authors: OLBRICHT T. , BENKER G. 
Published: August 2009

Abstract. Objectives. To review factors associated with development of osteoporosis in patients with rheumatic diseases, as well as the preventive and therapeutic measures.Design. A MEDLINE literature search.Results. 1 Pathogenesis. Rheumatoid arthritis in itself causes reduction of bone mass; this process can be aggravated by glucocorticoid treatment. With glucocorticoid treatment, bone mineral density decrease is most pronounced during the first months of treatment. There is no agreement on the effects of daily dose, cumulative dose, and duration of glucocorticoid treatment on the rate of bone loss. However, with treatment by low doses (< 10 mg of prednisone equivalent per day), bone loss appears to be minimal or even undetectable compared to controls. Alternate day treatment, or treatment with steroid ‘pulses’ have not been shown to protect from bone loss. 2 Prevention and treatment. Prophylactic and therapeutic measures for glucocorticoid‐induced osteoporosis include calcium supplementation, vitamin D in physiological doses and oestrogen in perimenopausal female patients. Efficacy has not always been shown in this particular indication but is extrapolated from other forms of osteoporosis. Limited data exist on treatment with anabolic steroids, calcitonin (with an additional analgesic effect) and biphosphonates and reduction of fracture rates has not yet been investigated. At present, there is insufficient evidence to show that altered steroid molecules can dissociate adverse effects on bone from clinically desirable effects.Conclusion. In view of the paucity of study data, prophylaxis and therapy of glucocorticoid‐induced osteoporosis should receive more attention in future clinical studies.
The influence of antihypertensive therapy on the structural arteriolar changes in essential hypertension: different effects of enalapril and hydrochlorothiazide
Authors: DAHLÖF B. , HANSSON L. 
Published: August 2009

Abstract. Objectives. To assess the peripheral and central haemodynamics, in particular the effect on minimal resistance in the hand, with an ACE inhibitor in comparison with a diuretic.Design. Double‐blind randomized parallel group study.Subjects. Twenty‐eight previously untreated men with essential hypertension (supine diastolic blood pressure > 95 mmHg repeatedly on placebo).Methods/intervention. Casual and intra‐arterial blood pressure, dye‐dilution technique, water plethysmography at rest and at ischaemia, enalapril (n = 14), hydrochlorothiazide (n = 14).Results. After 6 months the mean arterial pressure was reduced from 112.7 to 96.9 mmHg (change –15.9 mmHg; 95% confidence interval (CI) –21.9, –9.8) on enalapril and from 110.1 to 101.5 mmHg (change –8.6 mmHg; CI –14.4, –2.8). Heart rate did not change on any of the therapies. Enalapril reduced blood pressure mainly through a reduction in total peripheral resistance (Δ –3.0 PRU100; CI –5.6, –0.4) while hydrochlorothiazide reduced blood pressure mainly through a reduction in cardiac output (Δ –0.8 l/min−1 CI –1.5, –0.07). Minimal vascular resistance (mean of right and left hand) displayed a significant time × treatment interaction indicating a different trend with enalapril than hydrochlorothiazide with a change of –0.12 PRU100 (CI –0.33, 0.05) on enalapril and a change of 0.14 (CI –0.29, 0.56) on hydrochlorothiazide. The resistance level after 6 months was significantly higher on hydrochlorothiazide than on enalapril (P = 0.0105).Conclusion. Enalapril reduced blood pressure through vasodilatation and hydrochlorothiazide through decreased cardiac output. The two therapies also affected minimal vascular resistance (an indirect measure of vascular wall thickness) differently; with enalapril showing a favourable response in contrast to hydrochlorothiazide.
Liver damage from low‐dose oral contraceptives
Authors: LINDGREN A. , OLSSON R. 
Published: August 2009

Abstract. Objective. To study whether the decrease in the content of oestrogen and gestagen in modern low‐dose oral contraceptives (OC) has yielded a lower incidence of adverse liver reactions, and to describe the biochemical pattern of the adverse liver reactions from low‐dose OC.Design. We surveyed all liver reactions from OC reported to SADRAC (Swedish Adverse Drug Reactions Advisory Committee) from 1966 to 1989.Main outcome measure. Incidence of reported adverse liver reactions (number of reported adverse reactions/OC sales in defined daily dose [DDD]).Results. There was a sharp decline in the number of reports during the studied period, suggesting changes in reporting habits. However, there was also a significantly lower incidence of reports for medium‐compared to high‐oestrogen dose OC, and a further decrease, albeit non‐significant, in incidence with low‐oestrogen dose OC. Furthermore, in three comparisons of pairs of OC that differed only in the gestagen dose, there was a strong trend towards a higher reporting rate with higher gestagen dose. Cholestatic and hepatoceullular liver enzyme patterns were equally frequent in patients with adverse reactions from low‐dose oestrogen OC. There was no report of liver tumours related to use of low‐oestrogen dose OC.Conclusion. There seems to be a decrease in the incidence of adverse liver reactions related to lower contents of both oestrogens and gestagens in OC of the combined‐preparation type.