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Background Timely detection and treatment of hypertension prevents cardiovascular diseases. Formerly preeclamptic women are at increased risk for hypertension, but targeted and structural follow-up of these women is lacking. Purpose To develop a prediction model for the development of hypertension in the decade following preeclampsia in women who were initially normotensive shortly after pregnancy. Methods In this longitudinal cohort study, formerly preeclamptic women were invited twice for a cardiovascular assessment. The first visit took place at a median interval of 10 months after delivery and a second visit 10 years later as part of the Queen of Hearts cohort study on early detection of heart failure among young women with a history of preeclampsia (ClinicalTrials.gov Identifier NCT02347540). Normotensive women at the first visit were divided in two groups whether or not they had developed hypertension during visit 2. Hypertension was defined as SBP ≥130 mmHg and/or DBP ≥80 mmhg and/or use of antihypertensive medication. We developed a prediction model using multivariable logistic regression analysis. The model was internally validated with bootstrapping techniques. Results Of the 259 women, 185 (71%) were normotensive at first visit of which 49 (26%) had developed hypertension at the second visit. The prediction model, based on birth weight centile, mean arterial pressure, total cholesterol, left ventricular mass index and left ventricular ejection fraction, had a good to excellent discriminative ability of AUC-ROC-curve 0.82 (95% CI 0.75–0.89) with an optimism corrected AUC of 0.80. Sensitivity and specificity of our model to predict yearly 10% risk to develop hypertension was 98% and 65% respectively and positive- and negative-predictive values were 50% and 99% respectively. Conclusions Based on five easily available variables, we developed a good-to-excellent performing predictive tool to identify incident hypertension following preeclampsia in women that were normotensive shortly after pregnancy. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): This work was partially supported by funding of de Nederlandse Hartstichting (Dutch Heart Foundation, grant number: 2013T084, Queen of Hearts study)

Objective To evaluate the association between deferred delivery in early‐onset pre‐eclampsia and offspring outcome and maternal cardiovascular, renal and metabolic function in the postpartum period. Design Observational study. Setting Tertiary referral hospital. Population Nulliparous women diagnosed with pre‐eclampsia before 34 weeks’ gestation who participated in a routine postpartum cardiovascular risk assessment programme. Women with hypertension, diabetes mellitus or renal disease prior to pregnancy were excluded. Methods Regression analyses were performed to assess the association between pregnancy prolongation and outcome measures. Main outcome measures Offspring outcome and prevalence of deviant maternal cardiovascular, renal and metabolic function. Results The study population included 564 women with a median pregnancy prolongation of 10 days (interquartile range [IQR] 4–18) who were assessed at on average 8 months (IQR 6–12) postpartum. Pregnancy prolongation after diagnosis resulted in a decrease in infant mortality (adjusted odd ratio [aOR] 0.907, 95% CI 0.852–0.965 per day prolongation). This improvement in offspring outcome was associated with an elevated risk of moderately increased albuminuria (aOR 1.025, 95% CI 1.006–1.045 per day prolongation), but not with aberrant cardiac geometry, cardiac systolic or diastolic dysfunction, persistent hypertension or metabolic syndrome. Conclusion Pregnancy prolongation in early‐onset pre‐eclampsia is associated with improved offspring outcome and survival. These effects do not appear to be deleterious to short‐term maternal cardiovascular and metabolic function but are associated with a modest increase in risk of residual albuminuria. Tweetable abstract Pregnancy prolongation in pre‐eclampsia has only a limited effect on postpartum maternal cardiovascular function., Tweetable abstract Pregnancy prolongation in pre‐eclampsia has only a limited effect on postpartum maternal cardiovascular function.

The occurrence, formation and utilization of polysaccharides, lipids and poly-β-hydroxybutyrate in micro-organisms have been investigated. Bacteria belonging to the genus Arthrobacter were found to accumulate within their cells large amounts (up to 70% of their dry weight) of carbohydrates consisting mainly of polysaccharides. Yeast cells belonging to the Rhodotorulaceae synthesized large amounts of intra-cellular lipids (up to 50%). Some species in addition produced considerable quantities of extra-cellular lipids. The composition of intra- and extra-cellular lipids differed in their component fatty acids and alcohols. Poly-β-hydroxybutyrate was found to occur, in an amount of 30% of the dry cell weight, in the sewage bacterium Sphaerotilus natans; it was also detected in related sheath-forming bacteria. These polymeric compounds were synthesized under more or less similar cultural conditions viz. excess of glucose and deficiency of nitrogen. Lipids and presumably poly-β-hydroxybutyrate may be reserve materials, serving as substrates for endogenous metabolism. The function of polysaccharides is less clear.

Experiments were conducted in controlled environmental chambers to determine the influence of temperature on the phytotoxicity of seven soil-applied herbicides. Diclofop {2-[4-(2,4-dichlorophenoxy)phenoxy] propanoic acid} soil incorporated or surface applied, was more toxic to wild oat(Avena fatuaL.) shoots at 10 and 17 C than at 24 C. Efficacy of diclofop was enhanced with soil incorporation. Diclofop toxicity to wild oat roots was not influenced by a change in temperature. EPTC(S-ethyl dipropylthiocarbamate) stimulated sugarbeet(Beta vulgarisL. ‘American Crystal Hybrid B’) shoot dry weight production at 10 C and caused dry weight reduction at 24 C. Atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] toxicity to barley(Hordeum vulgareL. ‘Larker’) and alachlor [2-chloro-2′,6′-diethyl-N-(methoxymethyl)acetanilide] toxicity to oats(Avena sativaL. ‘Chief’) increased with increased temperature from 10 to 17 C. Temperatures within the range of 10 to 24 C did not affect trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine) toxicity to barley or BAY-5653 [N-(2-benzothiazolyl)-N-methylurea] or chloamben (3-amino-2,5-dichlorobenzoic acid) toxicity to oats.

SUMMARY: A methane-oxidizing bacterium, isolated from soil, was capable of fixing nitrogen. Nitrogenase activity could be assayed by acetylene reduction when the bacterium was growing on methanol but not when growing on methane, although 15N2 was fixed. Bacteria growing on methane co-oxidized ethylene but methanol-growing cells did not. The organism was extremely sensitive to oxygen when dependent on N2 as nitrogen source, a consequence of the sensitivity of its nitro-genase towards oxygen.

The influence of soil moisture on wild oat control from soil-incorporated methyl ester of diclofop {2-[4-(2,4-dichlorophenoxy)-phenoxy] propanoic} was determined in the greenhouse. Wild oat control with soil-incorporated diclofop at 1.5 or 3 ppmw increased linearly when soil moisture in a Tiffany sandy loam increased from 18.5 to 23.5% (75% to 125% of field capacity). The efficacy of soil-incorporated diclofop was not reduced when soil moisture was allowed to decrease from 21 (field capacity) to 18.5, 16, 13.5, or 11% (wilting point) before rewatering to 21%. The soil moisture level at the time of herbicide application determined the degree of wild oat control with soil-incorporated diclofop. Wild oat control with diclofop increased when a Tiffany sandy loam with 16% moisture (50% of field capacity) at the time of herbicide application, was watered to field capacity after 8 or 12 days delay, and control did not change with watering to field capacity at the time of herbicide application or when delayed 4 or 16 days. The movement of14C-diclofop in soil columns was greater within coarse than fine textured soils and increased with water volumes applied, regardless of soil type. Further, the leachability of14C-diclofop was two and a half times greater than that of14C-trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine).

Mise en evidence de l'apparition relative de divers groupes bacteriens apres apport de poudre de cellulose

Soil arthrobacters in contrast with coryneform bacteria from cheese surfaces may accumulate large amounts of an intracellular polysaccharide. This accumulation of reserve material leads to a much enlarged cell size.

In the course of an investigation into the effect of nitrogenous fertilisers on the growth and yield of cereal crops, it was observed that lodging is often the limiting factor in attaining maximal yields by increased nitrogen supply. This is particularly the case under the humid conditions prevailing in the Netherlands during the greater part of the growing season of the cereals. Although for the production of high grain yields some bending over of the ripe plants is desirable, severe lodging both from the point of view of grain formation and of harvesting is unprofitable. In order to learn the circumstances under which lodging occurs, a number of field and pot experiments with rye, wheat, barley and oats have been carried out from 1940 to 1949. In most of the field experiments nitrogen dressings have been combined with applications of other nutrients and with variations in rate of seeding and in spacing. Although many papers have dealt with the problem of lodging, there is considerable disagreement amongst various authors as to its cause. The first investigators who studied this phenomenon came to the conclusion

The mechanism of nitrate reduction in fungi and higher plants has been cleared up by Nason and E v a n s 3 8 and Nicholas and Nason 1 1 . In experiments with purified cell-free extracts they found that the nitrate->nitrite reaction is catalyzed by an enzyme with either flavin adenine dinucleotide (FAD) or flavin mononucleotide (FMN) as the prosthetic group and moreover molybdenum as a constituent. Reduced dior triphosphopyridine nucleotide (DPNH or TPNH) are required as electron donor. The reduction sequence was established to be as follows

A description is given of some microbiological tests for the determination of plant-available copper, magnesium and molybdenum in soils. In these investigationsAspergillus niger and in a few casesAzotobacter chroococcum andBact prodigiosum were used. From the figures obtained it is revealed that soils on which the plants are suffering from the so-called “reclamation disease”, have a much lower available copper content than those producing healthy crops. Soils on which the plants show the so-called “Hooghalen disease”, have a very low content of available magnesium. From these results and from experiments with cereals it is concluded that the “reclamation disease” is caused by a deficiency of plant-available copper and that a deficiency of available magnesium is the chief cause of the “Hooghalen disease”.

It is emphasized, that many constituents of the soil which are essential for the nutrition of plants, may be better estimated by biological than by chemical methods. Some such methods are described, especially those for the estimation of plant-available copper and magnesium, using the mold Aspergillus niger.

The effects of N, P and K nutrition on the amino-acid composition of tubers was studied. The composition of the soluble non-protein N was much affected by the mineral nutrition, whereas the protein composition remained fixed. Stem-end blackening of tubers and bluish-green coloration after boiling were found to be due to inadequate K-supply, which was correlated with a high tyrosine content, susceptibility to injury and increased respiration rate. Change in concentration of N, P, Mg or Gu had much less effect on this rate. Bruising stimulated the respiration of healthy cells. -J.F.C. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Thirty-fourSphaerotilus andLeptothrix strains were isolated from sewage, activated sludge and iron-containing ditch- and well-water, and their morphological and physiological characters studied. The organisms were grown under different conditions, e.g. on peptoneglucose agar and yeast-extract-manganous-carbonate agar, and in running ditch-water containing ferrous iron. Growth of these bacteria in synthetic media, with glucose as carbon source and aspartic and glutamic acids or inorganic nitrogen compounds as nitrogen source, required added vitamin B12 unless nitrogen was supplied as hydrolyzed casein or as a mixture ofl-amino acids. Methionine was found to be responsible for this replacement of vitamin B12.

The cause of the failure of the C2H2-C2H4 assay for nitrogen-fixing bacteria growing on lower alkanes was studied. Acetylene was a strong competitive inhibitor of methane oxidation for methane-utilizing bacteria, as well as for the oxidation of lower alkanes by other bacteria, so that energy and reducing power were no longer available for the reduction of acetylene by nitrogenase. Nitrogen-fixing bacteria grown on alkanes may reduce acetylene when intermediates of alkane-breakdown or other substrates oxidizable in the presence of acetylene are supplied. Ethylene co-oxidation is not responsible for the failure of the test, because acetylene also inhibits this co-oxidation along with methane oxidation.