The development of non-separation time-resolved fluoroimmunoassays for the measurement of urinary metabolites

We describe the principles of a new generation of sequential or simultaneous time-resolved fluoroimmunoassays, namely, simple, rapid, liquid-phase non-separation procedures which may be applied to the measurement of urinary steroid and drug metabolites. As an example, a method for the measurement of estrone-3-glucuronide in undiluted urine is reported. This method has a similar sensitivity, specificity and accuracy to a conventional separation fluoroimmunoassay or radioimmunoassay but in terms of speed, convenience, precision, reliability and clinical utility the new method has many advantages. The labelled antigen is a novel fluorescent europium chelate covalently linked to estrone-3-glucuronide. The antibody-binding reaction involves the incubation of the labelled antigen (2ng) with a limited concentration of polyclonal or monoclonal antibodies to estrone-3-glucuronyl-6-BSA and an aliquot of standard or sample (undiluted urine; 10 μl) in microtitre wells. After a 10 min incubation, the fluorescence which emanates from the antibody-free label is measured in a time-resolved fluorometer and is proportional to the concentration of estrone-3-glucuronide in the standard or sample. The method may be applied for the monitoring of ovarian function in women.     

Interaction of Mesna (2-mercaptoethane sulfonate) with the mutagenicity of cyclophosphamide in vitro and in vivo

The effects of sodium 2-mercaptoethane sulfonate (Mesna) on the mutagenicity of cyclophosphamide (CP) were assessed in vitro by the Ames test and in vivo in rats by analyzing micronuclei in bone marrow and mutagenic activity in urine. Mesna alone was negative in all test systems, while CP gave a positive response in all of them. In a combined treatment there was no significant reduction of the CP-induced mutagenicity in Salmonella. In rats the frequency of bone marrow micronuclei was not diminished when Mesna was given together with CP. May-Grunwald-Giemsa staining and Hoechst-Pyronin fluorescent staining techniques for micronuclei yielded similar results. The urine of rats treated with CP was mutagenic to Salmonella and no significant difference was observed when the rats had received both Mesna and CP. The results give support to the theory that Mesna acts primarily by reducing the toxicity of metabolites of CP, particularly acrolein, in the urinary tract and not by suppressing the mutagenicity of the active metabolites of CP.     

Coexistence in a guild of filter feeding caddis larvae: do different instars act as different species?

Summary Guild structure and coexistence of filter feeding caddis larvae was studied in three lake-outlet streams in northern Finland. Natural stones were used as sampling units, and for each stone measurements of six microhabitat variables were taken. Species and species instar relationships in the multivariate microhabitat space were analyzed by a method based on Principal Components Analysis. Seven species of filtering caddis larvae were found at the study sites, but detailed analysis was restricted to the four most abundant ones (Polycentropus flavomaculatus, Hydropsyche angustipennis, H. pellucidula, H. saxonica). P. flavomaculatus was the microhabitat generalist of the guild, whereas all the hydropsychids were narrowly specialized in at least one larval instar. In all species, different instars utilized the microhabitat somewhat differentially. Moss content and Froude number were significantly different between instar microhabitats in all comparisons. Ontogenetic niche changes not only separated species instars from each other, but also profoundly changed the biotic as well as abiotic environment of the species at different phases of larval development. This may have important effects on the dynamics of interacting species and, consequently, on the guild structure. While some of the more classical models of coexistence may also be relevant for understanding coexistence in this guild of sessile stream insects, ontogenetic niche changes clearly need to be taken into consideration in future studies of guild structure and species interactions of filter feeding caddisfly larvae.     

Ultrastructure of E1 + 2 + 9 + 12 inversion breakpoints in Drosophila subobscura

The ultrastructure of the Drosophila subobscura chromosome regions around the breakpoints of the complex E1 + 2 + 9 + 12 gene arrangement was analyzed. This overlapping inversion is formed by the association of the E1, E2, E9, and E12 simple inversions. Ultrastructure of sections involving 58D/59A, 61C/D, 62D/63A, 64B/C, 67A/B, and 68B/C breakpoints on Est chromosomes were compared with the ultrastructure of sections involving chromosomes were compared with the ultrastructure of sections involving 58D/68B, 62D/64C, 59A/63A, 64B/68C, 67B/61C, and 67A/61B breakpoints on E1 + 2 + 9 + 12 chromosomes. No detectable changes of structural organization on banding patterns induced by the E1 + 2 + 9 + 12 inversion were found. Ultrastructural analysis of the two E12 breakpoints has, however, facilitated the analysis of the left boundary of E12 inversion. Accordingly, we propose 61B/C as a new breakpoint instead of 61C/D.     

Eutrophication and recovery of Lake Vesijärvi (south Finland): Diatom frustules in varved sediments over a 30-year period

Lake Vesijärvi was loaded by sewage from the City of Lahti for 60 years until 1976 when the discharge was diverted. Paleolimnological analyses of the varved bottom sediment indicate that the sedimentation rate within the Enonselka basin, the most eutrophic part of the lake, has been as high as 2 cm yr^–1, and total phosphorus accumulation was 20–40 g P m^–2 yr^–1, during the last 20 years. Within the less eutrophic Laitialanselkä basin, the sedimentation rate did not exceed 1 cm yr^–1, and the formation of varved sediment only began at the end of the 1960's, i.e. about 10 years later than in Enonselkä.Planktonic diatom production was highest in the Enonselka basin. The most abundant diatoms in the sediment between 1970–1985 were Asterionella formosa, Aulacoseira islandica and Stephanodiscus spp. Fragilaria crotonensis and Tabellaria fenestrata had low abundances in the middle of the 1970's but increased again at the end of the 1970's. Asterionella formosa and Diatoma elongatum reached their maxima between 1979–1984 when the hypolimnion of the Enonselk/:a basin was aerated artificially. In the Laitialanselkä basin, the production of planktonic diatoms has been lower and the species composition of the diatom community differed from that in Enonselkä. However, at the end of 1980's the total accumulation of diatoms in Laitialanselkä approached levels which were observed at the end of 1950's in Enonselkä, prior to the rapid eutrophication period.The production and thereby the sedimentation of diatoms has decreased towards the end of the 1980's in Enonselkä, indicating reduced nutrient availability in the lake water. This reduction was due to the decreased external loading of phosphorus as well as to the decreased release of phosphorus from the sediment as a result of improved oxygen balance in the hypolimnion.     

Oxide-Based Solid-State Batteries: A Perspective on Composite Cathode Architecture

The garnet-type phase Li₇La₃Zr₂O₁₂ (LLZO) attracts significant attention as an oxide solid electrolyte to enable safe and robust solid-state batteries (SSBs) with potentially high energy density. However, while significant progress has been made in demonstrating compatibility with Li metal, integrating LLZO into composite cathodes remains a challenge. The current perspective focuses on the critical issues that need to be addressed to achieve the ultimate goal of an all-solid-state LLZO-based battery that delivers safety, durability, and pack-level performance characteristics that are unobtainable with state-of-the-art Li-ion batteries. This perspective complements existing reviews of solid/solid interfaces with more emphasis on understanding numerous homo- and heteroionic interfaces in a pure oxide-based SSB and the various phenomena that accompany the evolution of the chemical, electrochemical, structural, morphological, and mechanical properties of those interfaces during processing and operation. Finally, the insights gained from a comprehensive literature survey of LLZO–cathode interfaces are used to guide efforts for the development of LLZO-based SSBs.     

Effects of bovine colostrum supplementation on serum IGF-I, IgG, hormone, and saliva IgA during training

Mero, Antti, Heidi Miikkulainen, Jarmo Riski, RaimoPakkanen, Jouni Aalto, and Timo Takala. Effects of bovinecolostrum supplementation on serum IGF-I, IgG, hormone, and saliva IgAduring training. J. Appl. Physiol.83(4): 1144-1151, 1997.The purpose of this study was to examinethe effects of bovine colostrum supplementation (Bioenervi) on seruminsulin-like growth factor I (IGF-I), immunoglobulin G, hormone, andamino acid and saliva immunoglobulin A concentrations during a strengthand speed training period. Nine male sprinters and jumpersunderwent three randomized experimental training treatments of 8 daysseparated by 13 days. The only difference in the treatments was thedrink of 125 ml consumed per day. Posttraining increases were noticedfor serum IGF-I in the 25-ml Bioenervi treatment (125 ml contained 25 ml Bioenervi) and especially in the 125-ml Bioenervi treatment (125 mlcontained 125 ml Bioenervi) compared with the placebo (normal milkwhey) treatment (P < 0.05). The change in IGF-I concentration during the 8-day periods correlated positively with the change in insulin concentration during the sameperiods with 25-ml Bioenervi treatment(r = 0.68;P = 0.045) and with 125-ml Bioenervitreatment (r = 0.69;P = 0.038). Serum immunoglobulin G,hormone, and amino acid and saliva immunoglobulin A responses weresimilar during the three treatments. It appears that a bovine colostrumsupplement (Bioenervi) may increase serum IGF-I concentration inathletes during strength and speed training.

     

Development of needle retention in Scots pine (Pinus sylvestris) in 1957–1991 in northern and southern Finland

The needle trace method was used to study retrospectively the long-term latitudinal variation in needle retention in Scots pine (Pinus sylvestris L.) in Finland. The mean annual summer needle retention (ANR) along the main stem varied from 3.4 to 6.0 needle sets during the period 1957–1991. The lowest values were observed in southern and the highest in northern Finland. The length of the growing season, expressed as the thermal sum (threshold value +5 °C), was negatively correlated with the mean ANR (r=-0.96). The geographical needle retention pattern (NRP) for the period 1957–1991 showed a clearly increasing trend from 1957 to 1969 (southern Finland) and to 1975 (northern Finland); thereafter, the NRP tended to decrease close to its minimum value recorded in 1991. The general level of the NRP was approximately 5.0 needle sets in northern Finland and 3.5–4.0 needle sets in southern Finland. The NRP, with its 6–12 year cycle for southern Finland, was clearly periodical. Differences in the NRP among the ten stands in southern Finland were small, whereas the said periodicity was missing and the differences were high among the stands in northern Finland. The results indicate that variation in the number of needle sets, viz. defoliation of pines, is a normal phenomenon. The role of net carbon assimilation as a regulator of the number of needle sets is discussed.