Rhinitis,Asthma and Respiratory Infections among Adults in Relation to the Home Environment in Multi-Family Buildings in Sweden

Risk factors for rhinitis, asthma and respiratory infections in the home environment were studied by a questionnaire survey. Totally 5775 occupants (≥18 years old) from a stratified random sample of multi-family buildings in Sweden participated (46%). 51.0% had rhinitis in the last 3 months (current rhinitis); 11.5% doctor diagnosed asthma; 46.4% respiratory infections in the last 3 months and 11.9% antibiotic medication for respiratory infections in the last 12 months. Associations between home environment and health were analyzed by multiple logistic regression, controlling for gender, age and smoking and mutual adjustment. Buildings constructed during 1960–1975 were risk factors for day time breathlessness (OR = 1.53, 95%CI 1.03–2.29). And those constructed during 1976–1985 had more current rhinitis (OR = 1.43, 95%CI 1.12–1.84) and respiratory infections (OR = 1.46, 95%CI 1.21–1.78). Cities with higher population density had more current rhinitis (p = 0.008) and respiratory infections (p<0.001). Rented apartments had more current rhinitis (OR = 1.23, 95%CI 1.07–1.40), wheeze (OR = 1.20, 95%CI 1.02–1.41), day time breathlessness (OR = 1.31, 95%CI 1.04–1.66) and respiratory infections (OR = 1.13, 95%CI 1.01–1.26). Living in colder parts of the country was a risk factor for wheeze (p = 0.03) and night time breathlessness (p = 0.002). Building dampness was a risk factor for wheeze (OR = 1.42, 95%CI 1.08–1.86) and day time breathlessness (OR = 1.57, 95%CI 1.09–2.27). Building dampness was a risk factor for health among those below 66 years old. Odor at home was a risk factor for doctor diagnosed asthma (OR = 1.49, 95%CI 1.08–2.06) and current asthma (OR = 1.52, 95%CI 1.03–2.24). Environmental tobacco smoke (ETS) was a risk factor for current asthma (OR = 1.53, 95%CI 1.09–2.16). Window pane condensation was a risk factor for antibiotic medication for respiratory infections (OR = 1.41, 95%CI 1.10–1.82). In conclusion, rhinitis, asthma and respiratory infections were related to a number of factors in the home environment. Certain building years (1961–1985), building dampness, window pane condensation and odor in the dwelling may be risk factors.     

Solution Structures of Two Homologous Venom Peptides from Sicarius dolichocephalus

We present solution-state NMR structures for two putative venom peptides from Sicarius dolichocephalus. These peptides were identified from cDNA libraries created from venom gland mRNA and then recombinantly expressed. They are the first structures from any species of Sicarius spiders, and the first peptide structures for any haplogyne spiders. These peptides are homologous to one another, and while they have at most only 20% sequence identity with known venom peptides their structures follow the inhibitor cystine knot motif that has been found in a broad range of venom peptides.     

Tamoxifen fails to block estradiol accumulation,yet is weakly accumulated by the juvenile zebra finch anterior hypothalamus: An autoradiographic study

In experiment 1, we used autoradiographic procedures to examine whether tamoxifen could displace ³H-estradiol labeling in the anterior hypothalamus and the caudal nucleus of the ventral hyperstriatum (HVc) of ovariectomized 20-day-old female zebra finches. There was no significant reduction in labeling of cells by ³H-estradiol in birds preinjected with unlabeled tamoxifen. In experiment 2, we found that injections of ³H-tamoxifen causedweak labeling of cells in the anterior hypothalamus of 20-day-old male and female zebra finches. These results are compatible with the idea that tamoxifen does not block the action of estradiol in the brain of zebra finches, and suggest that the effects of early tamoxifen treatment on the morphology of the song system may reflect central action of tamoxifen.     

Pair formation in the Mongolian gerbil

This report describes the initial phase of social organization in Mongolian gerbils, Meriones unguiculatus, in large outdoor enclosures. These conditions offer a comparatively free choice for the establishment of bonds and social structure. In five replicate 20-day studies, the only social unit that formed was the male-female pair. The order of events was related to four sequential 5-day periods: (I) males established territories by male-male competition (1st to 2nd period); (II) females visited more than one male initially (1st and 2nd period), but developed a preference for one male or territory (3rd to 4th period); (III) as the females developed a preference, they also challenged other females having a preference for the same male or territory (approximately the 3rd period); (IV) as one female became locally dominant, some territorial males started chasing all but the dominant female. Males remained more active in territorial defence throughout the study. The defence became more intense as the females became strongly attached to one male and/or territory only. However females, after having established themselves in one particular male territory, spent significantly less time in the preferred area during the day of oestrus compared with the days before and after. Copulatory behaviour patterns, where observed, did not occur exclusively in interactions between territorial mates.     

QUANTITATIVE GENETIC ANALYSIS OF MORPHOLOGICAL VARIATION IN AN ANTARCTIC DIATOM GROWN AT TWO LIGHT INTENSITIES1

Ten clonal isolates of Thalassiosira tumida (Janisch) Hasle were grown in duplicate semi-continuous batch cultures at 116 and 11.6 μE·m⁻²·s⁻¹ acclimated cells were harvested during exponential growth and cleaned for examination by light microscopy (LM) and scanning electron microscopy (SEM). Number of strutted processes surrounding the central annulus (SP) and average number of satellite pores per process (AVSAT) were counted using SEM on 20 valves from each culture grown in high light, for a total of 400 valves examined; number of marginal labiate processes (LP) and overall diameter (DIAM) were measured using LM on 20 valves from each culture grown in both high and low light for a total of 800 valves examined. Univariate analysis of variance showed that bottle effects resulting from microenvironmental differences between replicates were a small but significant source of variation in DIAM, LP, and SP but not AVSAT. Significant differences among clones were observed for all characters. Decreased irradiance resulted in a significant decrease in valve diameter but no significant effect on LP; no light × clone interaction was observed. Significant covariance between characters among clones was also observed; since valve diameter is known to decrease during asexual growth, the correlation coefficients for SP, AVSAT, and LP with DIAM were used to correct the data for this source of nongenetic differences between clones. Analysis of the size-corrected data showed that the proportion of total phenotypic variance in SP, LP, and AVSAT caused by genetic differences among clones was 0.14, 0.14, and 0.30, respectively. This indicates that the majority of total phenotypic variance was due to environmental or developmental causes, but that sufficient genetic variability exists to support rapid phenotypic evolution in SP, LP, and AVSAT under continued directional selection. Finally, the results of the genetic analysis revealed a high (0.82) genetic correlation between SP and LP.     

Cloning and expression of cellulase and xylanase genes in Lactobacillus plantarum

Summary Eleven cellulase genes from Gram-positive bacteria were cloned in a Lactobacillus plantarum silage inoculum. Eight of these genes were expressed as active enzymes from their original promotors and translation signals. Where tested, the enzymes produced by transformed L.plantarum had the same temperature and pH optimum as enzymes produced in the original host, or in transformed Escherichia coli. Using chloramphenicol acetyltransferase as a cell-internal marker enzyme, it could be demonstrated that at least endoglucanase D from Clostridium thermocellum was actively secreted by transformed L. plantarum. In growing L. plantarum cultures, most of the enzymes were irreversibly inactivated when the pH decreased below 4.5. If the transformed strains were to be applied as an inoculum in silage, this pH inactivation might be useful in preventing overdigestion of the crop fibre. Offprint requests to: F. Michiels     

Endocytosis in mouse blastocysts: Characterization and quantification of the fluid phase component

Fluid phase endocytosis in mouse blastocysts was characterized using the fluid phase marker, ³H-dextran, which did not bind to the membrane. This nonsaturable uptake occurred via an energy-requiring process, with only 20% accountable by diffusion as indicated by analysis at 4°C. Insulin stimulated uptake of ³H-dextran by 30% (P<0.05) over the first hr. The rate of uptake then decreased in both control and insulin-treated blastocysts. However, by 2 hr, insulin-treated blastocysts contained 38% more ³H-dextran (38%; P<0.01) than control blastocysts. Incubation of blastocysts in protein-free medium increased ³H-dextran uptake to a rate equivalent to 12% of the blastocyst volume/min (1,500 ± 240 pliter/hr), compared to 4.5% and 1.5% of the blastocyst volume/min for uptake in the presence of 0.1 g BSA/I and 10 g BSA/I, respectively. Confocal microscopic studies of fluorescently labelled dextran uptake in blastocysts, cultured in the absence of BSA, showed an increase in weak fluorescence labelling in the trophectoderm cells of blastocysts, compared to blastocysts cultured in the presence of BSA. There was no diffusion of fluorescence label into the blastocoel cavity. This is consistent with fluid being endocytosed, possibly by a large number of small pinocytic vesicles. Thus fluid-phase endocytosis in blastocysts is stimulated by insulin, increasing the delivery of nutrient-containing fluid into blastocysts. In the absence of protein, embryos also increase fluid uptake, possibly in an attempt to maintain the rate of supply of protein nutrient to trophectoderm cells. An analysis of the rate of protein delivery in both adsorbed and dissolved phases is presented, which reveals the potential for significant contributions of both phases of endocytosis to blastocyst metabolism in vivo. © 1995 Wiley-Liss, Inc.