Impact of selective logging on inbreeding and gene dispersal in an Amazonian tree population of Carapa guianensis Aubl.

Selective logging may impact patterns of genetic diversity within populations of harvested forest tree species by increasing distances separating conspecific trees, and modifying physical and biotic features of the forest habitat. We measured levels of gene diversity, inbreeding, pollen dispersal and spatial genetic structure (SGS) of an Amazonian insect-pollinated Carapa guianensis population before and after commercial selective logging. Similar levels of gene diversity and allelic richness were found before and after logging in both the adult and the seed generations. Pre- and post-harvest outcrossing rates were high, and not significantly different from one another. We found no significant levels of biparental inbreeding either before or after logging. Low levels of pollen pool differentiation were found, and the pre- vs. post-harvest difference was not significant. Pollen dispersal distance estimates averaged between 75 m and 265 m before logging, and between 76 m and 268 m after logging, depending on the value of tree density and the dispersal model used. There were weak and similar levels of differentiation of allele frequencies in the adults and in the pollen pool, before and after logging occurred, as well as weak and similar pre- and post-harvest levels of SGS among adult trees. The large neighbourhood sizes estimated suggest high historical levels of gene flow. Overall our results indicate that there is no clear short-term genetic impact of selective logging on this population of C. guianensis.

Somatic stability of microsatellite loci in Eastern white pine, Pinus strobus L.

Variation at nuclear- and chloroplast-encoded microsatellite loci was studied among and within clonally propagated individuals of Eastern white pine. Total DNA was extracted and assayed from gamete-bearing tissue (megagametophytes) located on six different branch positions on each of 12 individual genets. No within-individual variation was observed among 12 loci studied. Estimates of numbers of mitotic cell divisions required to produce the tissue used as the source of genomic DNA were obtained by combining tree growth and anatomical data. This allowed for the calculation of upper bound estimates of numbers of mutations per locus per somatic cell division. The estimated somatic mutation rate was found to be substantially lower than those published for genomic microsatellite mutation rates in other plant species.

Entrapment of the lateral antebrachial cutaneous nerve exiting through the forearm fascia.

Isolated lateral antebrachial cutaneous nerve entrapment syndromes are uncommon. This report describes the compression of the lateral antebrachial cutaneous nerve of the forearm at the level of its passage through the superficial antebrachial fascia, distal to the elbow crease. Numbness and a painful dysesthesia over the radial aspect of the volar forearm were documented. Failure of conservative treatment necessitated surgical decompression.

Three-year clinical and angiographic follow-up after intracoronary radiation : results of a randomized clinical trial.

BACKGROUND: Although several early trials indicate treatment of restenosis with radiation therapy is safe and effective, the long-term impact of this new technology has been questioned. The objective of this report is to document angiographic and clinical outcome 3 years after treatment of restenotic stented coronary arteries with catheter-based (192)Ir. METHODS AND RESULTS: A double-blind, randomized trial compared (192)Ir with placebo sources in patients with previous restenosis after coronary angioplasty. Over a 9-month period, 55 patients were enrolled; 26 were randomized to (192)Ir and 29 to placebo. At 3-year follow-up, target-lesion revascularization was significantly lower in the (192)Ir group (15. 4% versus 48.3%; P<0.01). The dichotomous restenosis rate at 3-year follow-up was also significantly lower in (192)Ir patients (33% versus 64%; P<0.05). In a subgroup of patients with 3-year angiographic follow-up not subjected to target-lesion revascularization by the 6-month angiogram, the mean minimal luminal diameter between 6 months and 3 years decreased from 2.49+/-0.81 to 2.12+/-0.73 mm in (192)Ir patients but was unchanged in placebo patients. CONCLUSIONS: The early clinical benefits observed after treatment of coronary restenosis with (192)Ir appear durable at late follow-up. Angiographic restenosis continues to be significantly reduced in (192)Ir-treated patients, but a small amount of late loss was observed between the 6-month and 3-year follow-up time points. No events occurred in the (192)Ir group to suggest major untoward effects of vascular radiotherapy. At 3-year follow-up, vascular radiotherapy continues to be a promising new treatment for restenosis.

Reproducibility of impedance cardiography hemodynamic measures in clinically stable heart failure patients.

BACKGROUND AND AIMS. One of the greatest challenges confronting physicians who are managing the care of patients with heart failure is to acquire objective data that signals treatment effectiveness and/or disease progression. The aim of this study was twofold: 1) to determine the extent to which (real time) impedance cardiography measurements obtained with a specific medical device (the BioZ) were reproducible in outpatients with clinically stable heart failure; and 2) to establish "normal" ranges of one week hemodynamic variability in this population of patients. Information of this nature would help clinical cardiologists and primary care practitioners to evaluate the implications of their patient's visit-to-visit hemodynamic variability. METHODS. A one group, prospective, time series design was used. The sample consisted of 62 patients who had clinically stable heart failure and who were being treated in an outpatient heart failure clinic at a university medical center. BioZ hemodynamic measures of cardiac output, contractility, and after load were obtained at five points in time: two, 10, and 60 minutes resting following a 40-50 foot walk on the first day and at two and 10 minutes resting following a 40-50 foot walk on the second day, one week later. RESULTS. Small but significant changes in cardiac output and cardiac index (mainly due to changes in heart rate) were seen during the 60-minute period on week one. Stroke index did not change during this period. In general, reproducibility between measurements taken on the same day and between days was quite good. Establishment of 95% confidence intervals helped define boundaries of variability in this population. Further clinical evaluation of the four patients whose values exceeded the 95% confidence intervals revealed unexpected, potentially relevant changes that could have accounted for their interday variability. Conclusion. The BioZ impedance cardiography measurements are responsive to hemodynamic activity-rest changes and are reproducible at a one week interval in clinically stable heart failure patients being treated in an outpatient clinic. Stroke index is a better measure of patient status than cardiac output or cardiac index. (c)2000 by CHF, Inc.

Electroencephalographic responses to alcohol challenge in Native American Mission Indians.

BACKGROUND: Native Americans have some of the highest rates of alcohol abuse and dependence, yet potential central nervous system risk factors responsible for the problem drinking seen in some tribes remain relatively unknown. METHODS: Background electroencephalographic (EEG) variants and response to alcohol were investigated in 48 Native American Mission Indian men between 18 and 25 years old. RESULTS: Subjects with 50% or greater Native American heritage had a significantly higher proportion of low-voltage EEG variants. Within this sample of Mission Indian men, however, a family history of alcohol dependence was associated with a greater incidence of high voltage alpha EEGs. Mission Indian men also evidenced a "less depressant, more stimulating" response to alcohol as quantified by less alcohol-induced reductions in alpha, greater EEG stability, and increased alcohol-induced beta activity. CONCLUSIONS: These findings demonstrate that certain genetically regulated EEG variants that have been previously associated with risk for alcoholism in Caucasians may also be more common in these Mission Indian men. Additionally, EEG measures of response to alcohol do not provide support for the commonly held idea that Indians are more sensitive to the depressant effects of alcohol.

Two-year follow-up after catheter-based radiotherapy to inhibit coronary restenosis.

BACKGROUND: Although early trials indicate the treatment of restenosis with radiation therapy is safe and effective, the long-term impact of this new technology has been questioned. The possibility of late untoward consequences, such as aneurysm formation, perforation, and accelerated vascular disease, is of significant concern. Furthermore, it is not known whether the beneficial effects of radiation therapy will be durable or whether radiation will only delay restenosis. METHODS AND RESULTS: A double-blind, randomized trial was undertaken to compare 192Ir with placebo sources in patients with previous restenosis after coronary angioplasty. Patients were randomly assigned to receive a 0.76-mm (0. 03-in) ribbon containing sealed sources of either 192Ir or placebo. All patients underwent repeat coronary angiography at 6 months. All living patients were contacted 24 months after their index study procedure. Patients were assessed with respect to the need for target-lesion revascularization or nontarget-lesion revascularization, occurrence of myocardial infarction, or death. Over a 9-month period, 55 patients were enrolled; 26 were randomized to 192Ir and 29 to placebo. Follow-up was obtained in 100% of living patients at a minimum of 24 months. Target-lesion revascularization was significantly lower in the 192Ir group (15.4% versus 44.8%; P<0. 01). Nontarget-lesion revascularization was similar in 192Ir and placebo patients (19.2% versus 20.7%; P=NS). There were 2 deaths in each group. The composite end point of death, myocardial infarction, or target-lesion revascularization was significantly lower in 192Ir-treated versus placebo-treated patients (23.1% versus 51.7%; P=0.03). No patient in the 192Ir group sustained a target-lesion revascularization later than 10 months. CONCLUSIONS: At 2-year clinical follow-up, treatment with 192Ir demonstrates significant clinical benefit. Although further follow-up (including late angiography) will be necessary, no clinical events have occurred to date in the 192Ir group to suggest major untoward effects of vascular radiotherapy. At the intermediate follow-up time point, vascular radiotherapy continues to be a promising new treatment for restenosis.

A subgroup analysis of the Scripps Coronary Radiation to Inhibit Proliferation Poststenting Trial.

INTRODUCTION: In the Scripps Coronary Radiation to Inhibit Proliferation Poststenting (SCRIPPS) Trial, 192Ir significantly reduced angiographic, ultrasonographic, and clinical endpoints of restenosis. The objective of this analysis was to quantitate the impact of patient, lesion and technical characteristics on late angiographic outcome. METHODS: Patients with restenotic, stented coronary lesions were randomized to receive either 192Ir or placebo sources. Late luminal loss and loss index were calculated for several patient subgroups, including patients with diabetes, in-stent restenosis, multiple previous percutaneous transluminal coronary angioplasty (PTCA) procedures, longer lesion lengths, saphenous vein grafts, small vessel diameters, and minimum dose exposures < 8.00 Gy. Two-factor analysis of variance was used to test for an interaction between patient characteristics and treatment effect. RESULTS: In the treated group, late loss was particularly low in patients with diabetes (0.19 mm), in-stent restenosis (0.17 mm), reference vessel diameters < 3.0 mm (0.07 mm), and patients who received a minimum radiation dose to the entire adventitial border of at least 8.00 Gy. The loss index in each of these subgroups was similarly low at -0.02, 0.03, -0.02, and 0.03, respectively. By 2-factor analysis of variance, a significant interaction between subgroup characteristic and treatment effect (late loss) was found in patients with in-stent restenosis (p = 0.035), and patients receiving a minimum dose of 8.00 Gy to the adventitial border (p = 0.009). CONCLUSION: In this pilot study, patient characteristics associated with a more aggressive proliferative response to injury appeared to confer an enhanced response to radiotherapy. Furthermore, a dose threshold response to 192Ir was found with an enhanced response occurring when the entire circumference of the adventitial border was exposed to at least 8.00 Gy.

Portal decompression by transjugular intrahepatic portosystemic shunt and changes in serum-ascites albumin gradient.

The serum ascites albumin gradient (SAAG) is widely used to help determine the cause of ascites formation. A serum ascites albumin gradient of > or = 1.1 g/dL reliably distinguishes portal hypertension-related ascites from other causes. To date, there are no published data on the impact of portal decompression on this gradient. The recent development of transjugular intrahepatic portosystemic shunt (TIPS) allows for nonsurgical decompression of portal hypertension by radiologically creating a portosystemic shunt. This study examines the short-term impact of portal decompression on the serum ascites albumin gradient (SAAG) in patients with portal hypertension-related ascites undergoing transjugular intrahepatic portosystemic shunt. Portal pressure measurements were obtained before and after TIPS placement. Serum ascites albumin gradient was determined before and at 6 and 24 hours post-TIPS placement. Fifteen patients were enrolled in the study. The mean portosystemic gradient (PSG) before TIPS was 21.0 +/- 9.2 mmHg, whereas the post-TIPS mean PSG was reduced to 11.0 +/- 6.3 mmHg, consistent with portal decompression (p = 0.005). The mean pre-TIPS serum ascites albumin gradient was 1.9 +/- 0.5 g/dL and was reduced to 1.7 +/- 0.5 g/dL at 6 hours (p = 0.003) and 1.4 +/- 0.4 g/dL at 24 hours (p = 0.002) after TIPS placement. These findings further solidify the association between the SAAG and portal hypertension.

Are some of the effects of ethanol mediated through NPY?

Central administration of neuropeptide Y (NPY) in low concentrations has been shown to produce anxiolysis and suppression of locomotor activity, a behavioral profile not dissimilar to that of ethanol. The present study was conducted to ascertain whether NPY and ethanol have similar electrophysiological profiles and to evaluate the combined actions of NPY and ethanol. Eighty-five Wistar rats were stereotaxically implanted with electrodes aimed at dorsal hippocampus, amygdala, and frontal cortex. Rats were administered NPY [or saline (SAL)] intracerebroventricularly (i.c.v.) whereas the doses of alcohol (or SAL) were given intraperitoneally (i.p.). Two doses of alcohol (0.75, 1.5 g/kg) and two doses of NPY (1, 3 nmol) were given alone and in combination. Drug effects were assessed using event related potentials (ERP) recorded in response to an auditory "oddball" plus noise paradigm between 30 and 40 min post-drug. Multivariate analyses of variance (MANOVA) revealed that NPY produced a significant decrease in the amplitude and increase in the latency of the N1 component in cortex and a decrease in the amplitude of the P3 component in amygdala, but no overall effects in hippocampus. Ethanol produced identical effects to NPY on the N1 and P3 components of the ERP in cortex and amygdala. Combined administration of EtOH and NPY (1 nmol) produced effects equivalent to those seen following the higher doses of NPY (3 nmol) or EtOH (1.5 g/kg). These studies demonstrate that NPY and ethanol have a similar electrophysiological profile. In addition, the combined administration of NPY and ethanol produced additive effects.

Knowledge and attitude assessment of Quebec daycare workers and parents regarding HIV/AIDS and hepatitis B.

ISSUES: Cases of discrimination occur in Quebec daycares towards HIV-positive children as well as HIV-negative children born to seropositive parents. OBJECTIVES: Offer three-hour information sessions on bloodborne diseases, specifically HIV and hepatitis B, universal precautions, as well as legal, ethical and psychosocial aspects of HIV/AIDS to: 1) ensure that daycare workers have basic medical information on transmission of HIV and other bloodborne infections, 2) review basic hygiene including universal precautions, 3) link daycares to HIV/AIDS resources in their communities, and 4) facilitate the development of pro-active daycare policies for the integration of HIV-positive children. RESULTS: In total, 108 information sessions were given, in which 349 daycares participated. Results show an important difference in terms of knowledge and attitudes of the participants. Of the daycares which participated in the information sessions, 37% have developed their own pro-active policy.

Effect of combined anticoagulation and low-dose aspirin treatment on upper gastrointestinal bleeding.

Multiple studies link the use of nonsteroidal antiinflammatory drugs (NSAIDs) with severe upper gastrointestinal bleeding (UGIB); the incidence of such bleeding is 2-4%. One common regimen to assure patency after intracoronary stent placement requires an anticoagulant (warfarin) combined with aspirin as an antiplatelet agent. However, a 13-fold increase in the risk of UGIB occurs with long-term use of oral anticoagulants and NSAIDs. We retrospectively assessed the rate of UGIB in 138 patients who had received coronary stents (group I, receiving heparin followed by warfarin in combination with aspirin) and 109 angioplasty patients without stents (group II, receiving aspirin alone) between 1990 and 1994. UGIB was identified by hematemesis or melena, which led to gastrointestinal consultation. Patients were analyzed for multiple risk factors. UGIB occurred in 28 of 138 group I patients (20%; 95% CI 13.3-26.7%) and 0 of 109 group II patients (P < 0.0001). Esophagogastroduodenoscopy (EGD) findings on the 28 patients with UGIB included 13 patients with esophagitis or gastritis, 7 patients with gastric or duodenal ulcers, and 8 patients with no identifiable source of bleeding. UGIB occurred within a mean of 2.5 days of initiation of combination therapy. Of patients with UGIB, 10 required blood transfusion (mean number of units = 5.3). Previous history of peptic ulcer disease, smoking, and use of antiulcer medication did not significantly differ between the two groups. The concurrent use of anticoagulant and aspirin in patients with coronary stents creates a significant potential for UGIB and should be used only with extreme caution.

Analysis of T cell receptor beta chain expression by isoelectric focusing following gene amplification and in vitro translation.

We describe a new approach to analysis of T cell receptor diversity based on isoelectric focusing of in vitro translation products of amplified V region genes. The method is illustrated by analysis of V beta 2 profiles in peripheral blood lymphocytes from normal donors. The primers used for V beta 2 analysis spanned the V-(D-)J junction and included the segment from amino acid residue position 53 in the variable region to residue 132 of the constant region. The isoelectric focusing patterns display approximately 13-14 bands of varying intensity. Differences in expression of V beta 2-derived peptides were detected in comparisons of the isoelectric focusing profiles from different individuals, suggesting that the method may be useful for detecting genetically determined, immune response related or disease associated differences in Tcr V region expression. The major isoelectric focusing bands have been interpreted as representing groups of V beta 2 sequences sharing J beta region and NDN region charge similarity. Quantitative differences were detected in V beta 2 profiles of CD4 and CD8 T cell subpopulations indicating there may be selection for different charge characteristics in NDNJ sequences in the two T cell subsets. The method provides a new dimension for the detection of perturbations in the T cell repertoire.

Importance of historical contingency in the stereochemistry of hydratase-dehydratase enzymes.

There are two stereochemical classes of hydratase-dehydratase enzymes. Those that catalyze the addition of water to alpha, beta-unsaturated thioesters give syn addition-elimination stereochemistry, whereas those that catalyze the addition of water to conjugated carboxylate substrates give anti stereochemistry. This dichotomy could reflect different adaptive advantages or contingencies of separate evolutionary histories. Determination of the nonenzymatic stereochemistry of deuterium oxide addition to fumarate and to S-crotonyl N-acetylcysteamine has provided direct evidence for the importance of the contingencies of evolutionary history, rather than chemical efficiency, in the pathways of these hydratase-dehydratase enzymes.

Prevalence of right ventricular perfusion defects after inferior myocardial infarction assessed by low-level exercise with technetium 99m sestamibi tomographic myocardial imaging.

To assess the prevalence of right ventricular perfusion defects after a recent inferior wall myocardial infarction, 33 patients were studied 6 to 14 days after infarction with low-level exercise testing and technetium 99m (99mTc) sestamibi (SPECT) imaging. Twenty-two control subjects with a < 5% likelihood of coronary artery disease undergoing exercise 99mTc sestamibi imaging were also studied. For each image the right ventricle was computer isolated from reconstructed transverse cardiac slices, followed by reorientation into oblique slices. Both right and left ventricular images were visually assessed for defects. A quantitative method of defect detection was also applied to the right ventricle. For the right ventricle, 100% of the stress images and 96% of the rest images were adequate for interpretation. Right ventricular stress perfusion defects were identified in 10 (30%) of 33 patients with recent inferior infarction, with 50% completely or partially normalizing on rest images, consistent with ischemia. Of 14 patients with left ventricular inferoseptal defects, eight (57%) had right ventricular defects compared with 2 (11%) of 19 without inferoseptal defects (p < 0.005). We concluded that the right ventricle can be adequately assessed for perfusion defects by means of exercise with 99mTc sestamibi SPECT imaging. Defects of the right ventricle after inferior myocardial infarction occur frequently, and many have evidence of ischemia. Right ventricular perfusion defects are closely associated with left ventricular inferoseptal defects.

Comparison of dobutamine and exercise using technetium-99m sestamibi imaging for the evaluation of coronary artery disease.

Studies using dobutamine thallium-201 myocardial perfusion imaging have suggested a high sensitivity and specificity for the detection of coronary artery disease. However, few data are available comparing dobutamine with exercise stress for the detection and localization of perfusion defects. This study compared the effects of dobutamine and exercise stress using technetium-99m sestamibi single-photon emission computed tomographic imaging in the same patients in a prospective crossover trial. Twenty-four patients with a high likelihood of coronary artery disease underwent tomographic myocardial imaging at rest, after symptom-limited treadmill exercise, and after intravenous dobutamine (maximum 30 micrograms/kg/min). Tomograms of the left ventricle were divided into 20 segments and were interpreted without knowledge of patient identity or stress protocol. Dobutamine was well tolerated by all patients. Segment-by-segment concordance between exercise and dobutamine images was highly significant (kappa = 0.56, p < 0.0001). Global first-order agreement (normal vs abnormal) between exercise and dobutamine studies was 96% (kappa = 0.65, p = 0.02); global second-order agreement (normal vs fixed vs ischemic defect) was 88% (kappa = 0.45, p = 0.02). Regional first- and second-order agreement were 96 and 93%, respectively (p < 0.001 for both). Twenty patients underwent coronary angiography. Comparisons between exercise and angiography and between dobutamine and angiography were similar for both global agreement (95 vs 100%, p = NS) and regional agreement (77 vs 72%, p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Pretreatment with theophylline does not affect adenosine-induced thallium-201 myocardial imaging.

This study was designed to evaluate the effects of intravenous theophylline given before intravenous adenosine for thallium-201 imaging. Sixteen patients with known reversible thallium-201 defects were randomized to a double-blind crossover study of a 45-minute infusion of placebo or theophylline (given as the ethylenediamine salt, aminophylline, mean concentration 16.1 mg/L) before adenosine thallium-201 imaging. Adenosine was infused for 6 minutes at a rate of 140 micrograms/kg/min. Thallium-201 (2.5 to 3.0 mCi) was administered after 3 minutes of infusion. Blood pressure, heart rate, symptoms, and the electrocardiogram were monitored continuously. Planar thallium-201 imaging was obtained in three standard views and was interpreted using blinded segmental analysis and computerized quantitation. Systolic and diastolic blood pressure at baseline and during adenosine administration were similar following treatment with theophylline and placebo. The increase in heart rate observed during adenosine infusion was significantly reduced by theophylline pretreatment. Adenosine-induced symptoms (both cardiac and noncardiac) as well as ischemic electrocardiographic changes were significantly reduced after theophylline infusion (p < 0.05). In one patient, Mobitz type II heart block seen during adenosine infusion following placebo was absent with theophylline pretreatment. The size of adenosine-induced thallium-201 defects was unchanged by theophylline infusion using either segmental analysis (8 +/- 4 vs 9 +/- 5) or a computerized score (47 +/- 27 vs 45 +/- 21). Despite reduction in both symptoms and ischemic electrocardiographic changes, theophylline does not alter thallium-201 imaging following intravenous adenosine infusion.

Effects of intravenous theophylline on exercise-induced myocardial ischemia: II. A concentration-dependent phenomenon.

OBJECTIVES: The effects of varying concentrations of theophylline on exercise-induced myocardial ischemia were evaluated in patients with stable coronary artery disease. BACKGROUND: Theophylline is a competitive antagonist of adenosine and may have potential as an anti-ischemic medication. It is not known whether these effects on myocardial ischemia are concentration dependent. METHODS: In a double-blind, randomized, crossover manner, 11 patients received, at 1-week intervals, placebo and each of three theophylline doses by intravenous infusion for 45 min. Graded exercise testing was performed before randomization and immediately after each infusion. Concurrent anti-ischemic medications were withheld for 24 h before each exercise test. Serum theophylline concentrations achieved were 3.9 +/- 1.0 mg/liter (low), 8.2 +/- 1.8 mg/liter (medium) and 13.2 +/- 2.3 mg/liter (high). RESULTS: Compared with placebo, none of the three theophylline infusions produced a significant alteration in rest heart rate, blood pressure, mean frequency or severity of ventricular ectopic activity or noncardiac symptoms. The time to onset of ischemia was progressively increased, with medium and high concentrations achieving statistical significance. Similar patterns were observed for oxygen uptake and the heart rate-systolic blood pressure product at the onset of ischemia. Total exercise duration was significantly prolonged with the medium and high concentrations. CONCLUSIONS: It is concluded that administration of varying doses of theophylline before exercise produces a clinically significant and concentration-dependent improvement in the indicators of myocardial ischemia in patients with chronic stable coronary artery disease.

[Problems and eradication of Ambrosia artemisiifolia L. in Quebec in the urban and suburban environments]. / Problématique et répression d'Ambrosia artemisiifolia L. au Québec en milieux urbain et peri-urbain.

Ambrosia artemisiifolia is a common weed in Canada and it is one of the most important source of aero-allergenic pollen in the north-eastern part of North America. It is a problem mostly along roads in urban or suburban areas. It is easily controlled by herbicides but their use is increasingly restricted because of environmental considerations. Therefore, new methods must be developed to control this weed. Three types of controls were evaluated against Ambrosia artemisiifolia along an expressway in the summer of 1990. The control methods were hand weeding, mowing at 2 cm, 5 cm, or 8 cm, and crushing by a roadroller. These treatments were done at different dates in the course of the summer. Hand weeding was the most effective in reducing pollen and seed production although it was also the most expensive. Mowing was very effective when it was done at a height of 2 cm from the soil. It is the only height at which seed production was significantly reduced. Mowing efficacy in reducing pollen production tended to decrease with the raising of the mowing blade. The efficiency of weed pulling or moving improved when they were performed later in the growing season. Crushing was not an effective method of control. Mowing or hand weeding cannot eradicate Ambrosia artemisiifolia but if they are consistently used, they could reduce its population level over several years by decreasing seed production. The treatments either eliminated pollen production or reduced it at least by 88%, thereby insuring a relative relief for people allergic to the pollen of this plant.

Comparative endocrinological and clinical effects of percutaneous estradiol and oral conjugated estrogens as replacement therapy in menopausal women.

Sixty-three healthy post-menopausal women participated in the study aimed at determining the efficiency of percutaneous administration of estradiol (E2) giving physiological plasma levels of the estrogen to provide an efficient relief of climacteric and urogenital symptoms. Among these women, 31 had previous hysterectomy and were randomly allocated to one of the two estrogen replacement therapies while, similarly, the 32 women having an uterus were randomly divided between two groups who received in addition to estrogens, micronized oral progesterone. As estrogen, women received either E2 by percutaneous administration (Oestrogel) or oral conjugated estrogens (Premarin). With Oestrogel, serum E2 and estrone levels were within those seen during premenopause and showed a ratio close to 1.0. Climacteric symptoms were reduced or eliminated similarly in all groups. No changes was noticed on the concentration of serum angiotensinogen with Oestrogel therapy while a 2.5-fold increase was found in women receiving Premarin. As indicated by the 24-week endometrial biopsy, the progestational response induced by oral progesterone at the dose used was sufficient in twenty out of thirty-two women to cause endometrial atrophy, thus suggesting the need for higher amounts of micronized progesterone in a proportion of women. The present data also indicate that Oestrogel provides efficient relief of climacteric and urogenital symptoms without exerting any detectable effect on hepatic function while maintaining the ratio of serum E2/E1 at the physiological value of 1.0.