Metabolites in Blood for Prediction of Bacteremic Sepsis in the Emergency Room

A metabolomics approach for prediction of bacteremic sepsis in patients in the emergency room (ER) was investigated. In a prospective study, whole blood samples from 65 patients with bacteremic sepsis and 49 ER controls were compared. The blood samples were analyzed using gas chromatography coupled to time-of-flight mass spectrometry. Multivariate and logistic regression modeling using metabolites identified by chromatography or using conventional laboratory parameters and clinical scores of infection were employed. A predictive model of bacteremic sepsis with 107 metabolites was developed and validated. The number of metabolites was reduced stepwise until identifying a set of 6 predictive metabolites. A 6-metabolite predictive logistic regression model showed a sensitivity of 0.91(95% CI 0.69–0.99) and a specificity 0.84 (95% CI 0.58–0.94) with an AUC of 0.93 (95% CI 0.89–1.01). Myristic acid was the single most predictive metabolite, with a sensitivity of 1.00 (95% CI 0.85–1.00) and specificity of 0.95 (95% CI 0.74–0.99), and performed better than various combinations of conventional laboratory and clinical parameters. We found that a metabolomics approach for analysis of acute blood samples was useful for identification of patients with bacteremic sepsis. Metabolomics should be further evaluated as a new tool for infection diagnostics.     

Formin-like 1 (FMNL1) Is Regulated by N-terminal Myristoylation and Induces Polarized Membrane Blebbing

The formin protein formin-like 1 (FMNL1) is highly restrictedly expressed in hematopoietic lineage-derived cells and has been previously identified as a tumor-associated antigen. However, function and regulation of FMNL1 are not well defined. We have identified a novel splice variant (FMNL1γ) containing an intron retention at the C terminus affecting the diaphanous autoinhibitory domain (DAD). FMNL1γ is specifically located at the cell membrane and cortex in diverse cell lines. Similar localization of FMNL1 was observed for a mutant lacking the DAD domain (FMNL1ΔDAD), indicating that deregulation of autoinhibition is effective in FMNL1γ. Expression of both FMNL1γ and FMNL1ΔDAD induces polarized nonapoptotic blebbing that is dependent on N-terminal myristoylation of FMNL1 but independent of Src and ROCK activity. Thus, our results describe N-myristoylation as a regulative mechanism of FMNL1 responsible for membrane trafficking potentially involved in a diversity of polarized processes of hematopoietic lineage-derived cells.     

Morphological gradients in the starling basilar papilla

The starling cochlea was studied with TEM at four locations along the basilar papilla to investigate gradients in morphological features over the papilla's length and width. Hair cell shape changes continuously from neural to abneural and from basal to apical. Unlike the situation in mammals, there are no distinct populations of hair cells; the previously described types (tall hair cells and short hair cells) are merely extremes in a continuum. Contacts between THC are a normal feature. Except at the base of the papilla, SHC have very large cuticular plates, suggesting a micromechanical function for these cells. In contrast to the THC, the SHC normally completely lack afferent innervation; this indicates that their function is restricted to within the basilar papilla itself. © 1992 Wiley-Liss, Inc.     

Do pollen beetles need pollen? The effect of pollen on oviposition,survival, and development of a flower‐feeding herbivore

Abstract.  1. Pollen is considered to be an important dietary component for many species of flower-feeding herbivores. Its influence on oviposition site selection by the pollen beetle Meligethes aeneus , and on the development of its larvae was investigated.
2. The effects of pollen presence and absence on adult, egg, and larval incidence in the field, and on larval development in the laboratory were compared through the use of Synergy, a composite hybrid oilseed rape Brassica napus variety comprising male-fertile (with pollen) and male-sterile (without pollen) plants.
3. In the field, adult females were more abundant on male-fertile plants during flowering, and a greater proportion of male-fertile than male-sterile buds were accepted for oviposition. These data indicate a possible role of pollen in oviposition site selection by female pollen beetles.
4. The numbers of first instar larvae on the two plant lines did not differ; however, more second instars were found on male-fertile than on male-sterile flowers. This suggests a greater larval survival on male-fertile plants, possibly due to the more readily available food resources and better nutrition afforded by the presence of pollen.
5. Laboratory experiments confirmed that a diet which included pollen improved survival to adulthood and resulted in heavier pupae and adults; however, pollen was not obligatory for larval survival and development.
6. The pollen beetle, previously thought to be an obligate pollen feeder, is therefore more generalist in its requirements for development. These findings may relate to the nutritional and behavioural ecology of other flower-feeding herbivores.     

Plant responses to H2S and SO2 fumigation. I. Effects on growth, transpiration and sulfur content of spinach

Exposure of spinach (Spinacia oleracea L. cv. Monosa) to 0.25 μl l_?1 H₂S reduced the relative growth rate by 26, 47 and 60% at 15, 18 and 25°C, respectively. Shoot to root ratio decreased in plants fumigated at 18 and 25°C. Growth of spinach was not affected by a 2-week exposure to 0.10 or 0.25 μl l_?1 SO₂. Both H₂S and SO₂ fumigation increased the content of sulfhydryl compounds and sulfate. A 2-week exposure to 0.25 μl l_?1 H₂S resulted in an increase in sulfhydryl and sulfate content of 250 to 450% and 63 to 248% in the shoots, respectively, depending on growth temperature. Exposure to 0.15 and 0.30 μl l_?1 H₂S at 20°C for 2 weeks resulted in a 46% increase in sulfate content of the shoots at 0.30 μl l_?1 and no detectable increase at 0.15 μl l_?1 H₂S; the sulfate content of the roots increased by 195 and 145% at 0.15 and 0.30 μl l_?1 H₂S, respectively. Fumigation with 0.25 μl l_?1 SO₂ at 20°C for 2 weeks resulted in an increase in sulfhydryl content and sulfate content in the shoots of 285% and 300 to 1100%. H₂S fumigation during the 12 h light period or only during the dark period resulted in identical growth reduction and accumulation of sulfhydryl compounds; they were about 50 and 67% of those observed in continuously exposed plants. H₂S- and SO₂-exposed plants showed an increased transpiration rate, which was mainly caused by an increased dark-period transpiration. No effect of H₂S and SO₂ on the water uptake of the plants and the osmotic potential of the leaves was detected. Plants fumigated with 0.25 μl l_?1 H₂S for 2 weeks were smaller and differed morphologically from the control plants by slightly more abaxially curved leaf margins. Cross sections of the leaves showed smaller cells at the margins and smaller and fewer air spaces. The increased transpiration in the H₂S-exposed plants is discussed in relation to the observed morphological changes.     

5'-modified agonist and antagonist (2'-5')(A)n analogues: synthesis and biological activity

Two 5'-modified (2'-5')(A)4 oligomers with an increased resistance to phosphatase degradation were synthesized and evaluated for their ability to develop an antiviral response when introduced into intact cells by microinjection or by chemical conjugation to poly(L-lysine). The enzymatic synthesis of 5'-gamma-phosphorothioate and beta,gamma-difluoromethylene (2'-5')(A)4 from adenosine 5'-O-(3-thiotriphosphate) and adenosine beta,gamma-difluoromethylenetriphosphate by (2'-5')-oligoadenylate synthetase is described. The isolation and characterization of these (2'-5')(A)4 analogues were achieved by high-performance liquid chromatography. The structures of 5'-modified tetramers were corroborated by enzyme digestion. These two 5'-modified tetramers compete as efficiently as natural (2'-5')(A)4 for the binding of a radiolabeled (2'-5')(A)4 probe to ribonuclease (RNase) L. Nevertheless, at the opposite to 5'-gamma-phosphorothioate (2'-5')(A)4, beta,gamma-difluoromethylene (2'-5')(A)4 failed to induce an antiviral response after microinjection in HeLa cells. In addition, it behaves as an antagonist of RNase L as demonstrated by its ability to inhibit the antiviral properties of 5'-gamma-phosphorothioate (2'-5')(A)4 when both are microinjected in HeLa cells. The increased metabolic stability of 5'-gamma-phosphorothioate (2'-5')(A)4 as compared to that of (2'-5')(A)4 was first demonstrated in cell-free extracts and then confirmed in intact cells after introduction in the form of a conjugate to poly(L-lysine). Indeed, 5'-gamma-phosphorothioate (2'-5')(A)4-poly(L-lysine) conjugate induces protein synthesis inhibition and characteristic ribosomal RNA cleavages for longer times than unmodified (2'-5')(A)4-poly(L-lysine) in the same cell system.(ABSTRACT TRUNCATED AT 250 WORDS)     

Contribution of leaves of different ages to plant carbon balance as affected by potassium supply and water stress

The carbon balances of whole, 21-d old French bean plants (Phaseolus vulgaris L.) grown in standard nutrient solution (1K) and its modifications without (OK) or surplus (2K) potassium were calculated from the daily photosynthetic carbon inputs of individual leaves, and the daily respiratory carbon losses by individual leaves, stalks and petioles, and roots. Under the three K concentrations, maximum net photosynthetic rates (P_n) were found in the 2nd or in the 3rd trifoliate leaves, maximum respiratory rates (R_d) in the youngest, 4th trifoliate leaves; the P_n/R_d ratio decreased with leaf age. In all leaves of 2K plants, leaf dry masses and thicknesses, P_n, P_n/P_d ratios, and stomatal and intracellular conductances were lower than in OK and IK plants. Daily whole-plant net carbon gain was highest in IK plants, whereas in OK and 2K plants it was 98.0 and 81.3 % of IK, respectively. Similar values were found in the parameters of growth analysis, namely in net assimilation rates and relative growth rates. No differences were found in water potential (Ψ _w ) or water saturation deficit (W_sat) in the OK, 1K and 2K plants sufficiently supplied with water or during wilting and resaturation. The decrease in Ψ_w to −0.97 MPa was associated with a 19.9 %, 31.4 % and 23.4 % decrease in P_n of OK, 1K and 2K plants, respectively, but no effect on R_d was found. In the three variants, the short-time effect of mild water stress was fully reversible.     

alpha-DNA. VI: Comparative study of alpha- and beta-anomeric oligodeoxyribonucleotides in hybridization to mRNA and in cell free translation inhibition.

alpha and beta-anomeric d(G2T12G2) oligodeoxyribonucleotides were compared for their hybridization to rA12: the observed melting temperatures are 27 degrees C for beta-oligodeoxyribonucleotide/RNA hybrid and 53 degrees C for alpha-oligodeoxyribonucleotide/RNA. alpha-oligonucleotides with the four bases, complementary to natural mRNAs, were synthesized for the first time, labeled at their 5'-end with [32P] and used as probes in Northern blot experiments. In spite of these higher affinities for their target RNA's, they were unable to block translation of natural or synthetic mRNA's in rabbit reticulocyte lysate. We have studied the RNase H activity on model rA12:alpha- or beta-d(G2T12G2) hybrids or on mRNA:alpha- or beta-oligonucleotides hybrids. Specific hybridization protects RNA strech when using alpha-oligonucleotides but not beta-oligonucleotides. Thus, our results show the inability of RNase H to degrade RNA in alpha-oligodeoxyribonucleotides:RNA duplexes.