Normal fetal growth in women with antiphospholipid syndrome treated with high-dose intravenous immunoglobulin (IVIG)

Antiphospholid antibodies are associated with fetal distress and fetal death. Although different therapeutic regimens have been used, the incidence of fetal growth retardation varies between 30 and 60 per cent of reported cases. We report the evolution of fetal growth in patients with antiphospholipid antibody syndrome treated with high-dose intravenous immunoglobulins (IVIG). Fourteen patients with a history of recurrent spontaneous abortion and immunological diagnosis of antiphospholipid syndrome were followed longitudinally. Intravenous immunoglobulin at a dose of 0.5 g/kg body weight for two consecutive days was started from the fifth week of pregnancy and repeated every 4 weeks until the 33rd week of gestation. Fetal biometry was evaluated longitudinally from the appearance of the gestational sac at 4 weekly intervals. In the period between 26 and 34 weeks, the frequency of evaluation was increased to every 14 days. Data obtained were compared with a control group of 70 fetuses with uneventful pregnancies matched for gestational age. Neonatal weight is shown in relation to the centiles for the normal population. One patient out of 14 (7.1 per cent) developed gestational hypertension and abruptio placentae. No other pregnancy complications were seen. No proteinuria was found. The mean maternal age was 31.2±3.8 years. Median birth weight was 3433 g±287. The median centile of the birth weight was 65.3±18.6. Mean gestational age at delivery was 1.3 weeks. No fetal or neonatal growth retardation was seen. No significant differences were found in the biometrical parameters investigated in the various gestational ages vs. the control group (Student's t-test not significant); a significant increase in head circumference (P< 0.001) and abdominal circumference (P< 0.05) was found at 36–37 weeks gestational age in the IVIG-treated fetuses. The presence of antiphospholipid antibodies is considered detrimental for pregnancy outcome because of their negative effects on placental vascular perfusion and fetal transfer of metabolites. The use of IVIG seems to avoid or inhibit the reduced availability of nutrients for the fetal anabolic functions, as the expected reduction in fetal growth was not seen in our series.     

Amiodarone treatment in pregnancy for dilatative cardiomyopathy with ventricular malignant extrasystole and normal maternal and neonatal outcome

Amiodarone treatment in pregnancy might be difficult to handle because of the long half-life of the drug (14–28 days up to 2 months) and because it reduces maternal and neonatal thyroid activity. Although short-term use in pregnancy has been described in cases of fetal supraventricular tachycardia, there are few reports on the chronic use of the drug. In this paper we describe our experience with amiodarone treatment in two pregnant sisters with familial dilatative cardiomyopathy and ventricular malignant extrasystole. Prolonged administration of amiodarone (400–200 mg/die) since the beginning of pregnancy did not have any adverse effects; maternal and neonatal thyroid function was normal, as was the neurological and motor development of the neonates.     

Seasonal variations in nitrogen-fixation (acetylene reduction) and sulphate-reduction rates in the rhizosphere of Zostera noltii: nitrogen fixation by sulphate-reducing bacteria

Nitrogen-fixation (acetylene reduction) rates were measured over an annual cycle in meadows of the seagrass Zostera noltii Hornem in the Bassin d'Arcachon, south-west France, between March 1994 and February 1995, using both slurry and whole-core techniques. Measured rates using the slurry technique consistently overestimated those determined on whole cores, probably due to the release of labile organic carbon sources as a result of root damage during preparation of the slurries. Thus, the whole-core technique may provide a more accurate estimate of in situ activity, since disturbance of physicochemical gradients of oxygen, sulphide, nutrients and the relationship between the plant roots and the rhizosphere microflora is minimised. Rates measured by the whole-core method were 1.8- to 4-fold greater (dependent upon season) in the light than those measured during dark incubations, indicating that organic carbon diffusing from the plant roots during photosynthesis was an important factor in regulating nitrogen fixation in the rhizosphere. Additions of sodium molybdate, a specific inhibitor of sulphate-reducing bacteria (SRB) inhibited acetylene-reduction activity by >80% as measured by both the slurry and whole-core techniques throughout the year, inferring that SRB were the dominant component of the nitrogen-fixing microflora. A mutualistic relationship between Z. noltii and nitrogen-fixing SRB in the rhizosphere, based on the exchange of organic carbon and fixed nitrogen is proposed. Acetylene- and sulphate-reduction rates showed distinct summer peaks which correlated with a reduced availability of ammonium in the sediment and the annual growth cycle of Z. noltii in the basin. Overall, these data indicate that acetylene reduction (nitrogen fixation) activity in the rhizosphere of Z. noltii was regulated both by the availability of organic carbon from the plant roots and maintenance of a low NH ₄ ⁺ concentration in the vicinity of the plant roots due to efficient assimilation of NH ₄ ⁺ by Z. noltii during the growth season. Nitrogenfixation rates determined from acetylene-reduction rates measured using the whole-core technique ranged from 0.1 to 7.3 mg N m^-2d^-1, depending on season, and were calculated to contribute between 0.4 and 1.1 g N m^-2yr^-1, or 6.3 to 12% of the annual fixed nitrogen requirement of Z. noltii.     

QUANTIFICATION OF INSTREAM FLOW NEEDS OF A WILD AND SCENIC RIVER FOR WATER RIGHTS LITIGATION1

ABSTRACT: The lower 4 miles of the Red River, a tributary of the Rio Grande in northern New Mexico, was designated as one of the “instant” components of the National Wild and Scenic River System in 1968. The Bureau of Land Management (BLM), as the managing agency of the wild and scenic river, was a participant in a general water rights adjudication of the Red River stream system. The BLM sought a federal reserved water right and asserted a claim to the instream flows necessary to protect and maintain the values of the river. Instream flows are not recognized under New Mexico water law. Instream flow requirements were determined by several methods to quantify the claims made by the United States for a federal reserved water right under the Wild and Scenic Rivers Act. The scenic (aesthetic), recreational, and fish and wildlife values are the purposes for which instream flow requirements were claimed. Since water quality is related to these values, instream flows for waste transport and protection of water quality were also included in the claim. The U.S. Fish and Wildlife Service's Instream Flow Incremental Methodology was used to quantify the relationship between various flow regimes and fish habitat. Experience in this litigation indicates the importance of using state-of-the-art methodologies in quantifying instream flow claims. The incremental methodology held up well under technical and legal scrutiny and is an example of the latest methodology that was applied successfully in an adjudication. On February 23, 1984, the parties involved in the adjudication entered a precedential stipulation recognizing a federal reserved right to instream flows for the Red River component of the National Wild and Scenic River System.     

Use of agricultural land evaluation and site assessment in Linn County,Oregon, USA

Oregon state law requires each county in the state to identify agricultural land and enact policies and regulations to protect agricultural land use. State guidelines encourage the preservation of large parcels of agricultural land and discourage partitioning of agricultural land and construction of nonfarm dwellings in agricultural areas. A land evaluation and site assessment (LESA) system was developed in Linn County to aid in the identification of agricultural land and provide assistance to decision makers concerning the relative merits of requests to partition existing parcels of ricultural land and introduce nonagricultural uses.Land evaluation was determined by calculating soil potential ratings for each agricultural soil in the county based on the soil potentials for winter wheat, annual ryegrass, permanent pasture, and irrigated sweet corn. Soil potential ratings were expressed on a scale of 0 to 150 points. The land evaluation score for a parcel consists of the weighted average soil potential rating for all of the soils in the parcel, weighted by the percentage of each soil present in the parcel.Site assessment was based on the size of a parcel and on the amount of existing conflict between agricultural and nonagricultural uses, particularly rural residential uses, both adjacent to and in the vicinity of a parcel. Parcel size refers to both size in relation to a typical field and size in relation to a typical farm unit. Conflict takes into account the number of nonfarm dwellings within 1/4 mile (0.4 km) of a parcel, the amount of the perimeter that adjoins conflicting land uses, and the residential density adjacent to the parcel. Empirical scales were derived for assigning points to each of the site assessment factors. Both parcel size and conflict were worth 75 points in the model. For parcel size, 45 points were allocated to field size and 30 points to farm-unit size. For conflict, 30 points were allocated to nonfarm dwellings within 1/4 mile and 45 points to perimeter conflicts.The LESA model was validated by testing on 23 parcels in Linn County for which requests to partition and/or convert to nonagricultural uses had been received by the County Planning Department. This testing was an essential part of the development process, as it pointed out inconsistencies and errors in the model and allowed continuous adjustment of factors and point scales. The results of application of the final model to three of the case studies are presented to illustrate the concepts.Three possible uses of the information generated by the LESA system include determining the relative agricultural value of a parcel, determining grades of agricultural land suitability, and determining the impacts of changing land use on other parcels in the vicinity. Relative agricultural value is a direct outcome of application of the evaluation criteria in the LESA model. Good, marginal, and nonagricultural grades of agricultural suitability were determined by examining the data from all 23 test cases and establishing threshold point values for soil quality, conflict, parcel size, and total LESA score. Impact analyses were not done in this study, but could be achieved by calculating LESA scores for all parcels possibly affected by a land-use change both before and after a proposed change. All three applications fall short of making a specific land-use decision, but they do provide information that should be of value to the local jurisdiction charged with making such decisions.     

THE VALUES OF GOODS AND SERVICES–IMPLICATIONS FOR A FLEXIBLE NATIONAL WATER POLICY1

ABSTRACT: This paper evolved from a concern that water resource administrators and planners do not have a consistent definition of the value of goods and services of outputs from projects and programs. A more flexible approach to planning and evaluation is presented that recognizes the interaction of production and consumption through the use of commodity demand curves. Use of the concept of consumer surplus permits measurement of the differential impacts on producers' and consumers' welfare. Quadratic programming is suggested as a consistent means of quantifying these differential impacts.     

THE USE OF BIOLOGICAL CRITERIA IN ENVIRONMENTAL POLICY1

ABSTRACT: The hypothesis of this paper is that regulatory systems for the control of effluent released to the environment can be, if improperly designed, inadequate for both the establishment of effective pollution control policy and the assessment of the biological significance of violations. This inadequacy may stem from several factors: first, the use of single point standards which delineate the boundary between legally acceptable and unacceptable pollutant discharges; and second, the existence of significant weaknesses in the frequency and design of monitoring programs. In order to be effective, pollution standards must reflect the impact of pollutants on the ecosystem. To achieve this goal, three critical pieces of information are required: measurement of ambient levels of released pollutants, frequency distributions derived from these data, and estimates of biological damage functions. Illustrating the above three requirements with data drawn from research in British Columbia, the authors recommended a restructuring of environmental policy to provide regulatory agencies with an effective mechanism for the analysis and control of environmental degradation.     

Comparisons of forager distributions from matched honey bee colonies in suburban environments

We conducted experiments designed to examine the distribution of foraging honey bees (Apis mellifera) in suburban environments with rich floras and to compare spatial patterns of foraging sites used by colonies located in the same environment. The patterns we observed in resource visitation suggest a reduced role of the recruitment system as part of the overall colony foraging strategy in habitats with abundant, small patches of flowers. We simultaneously sampled recruitment dances of bees inside observation hives in two colonies over 4 days in Miami, Florida (1989) and from two other colonies over five days in Riverside, California (1991). Information encoded in the dance was used to determine the distance and direction that bees flew from the hive for pollen and nectar and to construct foraging maps for each colony. The foraging maps showed that bees from the two colonies in each location usually foraged at different sites, but occasionally they visited the same patches of flowers. Each colony shifted foraging effort among sites on different days. In both locations, the mean flight distances differed between colonies and among days within colonies. The flight distances observed in our study are generally shorter than those reported in a similar study conducted in a temperate deciduous forest where resources were less dense and floral patches were smaller.