Re-expression by Candida albicans germ tubes of antigens lost during subculture of blastospores

The effect of germ tube induction on the antigenic variability in C. albicans was studied in strains from blood cultures (Group I) and superficial candidiasis (Group II). When compared by immunoblotting with a rabbit antiserum, antigenic extracts from Group I strains grown as blastospores showed a higher reactivity than that of Group II strains. Major bands in Group I strains (45–47, 33, 30 kDa) were continuously expressed through the subcultures in vitro but, with the exception of the 45 kDa band, the reactivity of all of them decreased or disappeared after the tenth subculture in Group II strains. The induction of the germ tubes produced the re-expression of the antigens lost during subculture in the yeast form, the effect being very clear in Group II strains. The re-expression by C. albicans germ tubes of antigens lost during subculture of blastospores in vitro and the higher reactivity shown by Group I strains grown in mycelial phase should be taken into consideration when a test to detect anti-C. albicans antibodies is to be developed.Abbreviations GYE glucose-yeast extract agar     

MORPHOLOGICAL VARIATION WITHIN AND BETWEEN NATURAL POPULATIONS OF NON-TIDE POOL FUCUS DISTICHUS (PHAEOPHYTA) IN NEW ENGLAND1,2

The sources of morphological variation in natural populations of Fucus distichus L. ssp. edentatus (De la Pyiaie) Powell and F. distichus L. ssp, evanescens (C. Agardh) Powell from New England were evaluated. Individuals from different populations were morphologically distinct as judged by population means and analysis of variance. A correlation between the plant's form and its habitat was established by field observation. The broadest material grows in calm estuarine habitats, while the narrowest plants occur in exposed, open coastal areas. Major differences in morphology also appear seasonally. In addition, microhabitat factors such as exposure to wave action and elevation explain some morphological variation. Cultured germlings from distinct populations of “evanescens” and “edentatus” type plants were outplanted to an experimental garden in order to ascertain whether the variation was heritable or environmentally induced. The latter experiments indicate that major differences in morphology are genetically determined.     

Genetic analysis of morphological index and its related taxonomic traits for classification of indica/japonica rice

A doubled haploid population derived from anther culture of ZYQ8/JX17 F₁, a typical indica and japonica hybrid, was used in this study. Morphological index and its related taxonomic traits were investigated in 121 DH lines. The quantitative trait loci (QTLs) for morphological index and its related taxonomic traits were analyzed. Two major QTLs for leaf hairiness, three QTLs for length/width of grain, one QTL for color of hull when heading, one QTL for hairiness of hull, two QTLs for length of the first and second panicle internode, and one major QTL and two QTLs for phenol reaction were detected. Four QTLs for morphological index were also identified on chromosomes 1, 3, 4 and 6, respectively, three of which on chromosomes 1, 3 and 6, respectively, were found to be located in the same chromosome regions where some QTLs for the related taxonomic traits were located.     

Reading shell shape: implications for palaeoenvironmental reconstructions. A case study for bivalves from the marine Quaternary of Argentina (south-western Atlantic)

Most research on bivalves from the south-western Atlantic used morphological (shell) characters for taxonomic discriminations. Dominant Veneroids from Argentinian Quaternary coastal deposits exhibit wide morphological variation – often making objective discriminations difficult/impossible, which could be objectively described and compared through geometric morphometrics techniques. This work focuses on comparison of geometric morphometrics methods applied to fossil and modern shells, to assess inter- and intra-generic variations. Three approaches were considered: landmarks (L), semi-landmarks (SL) and outlines. Shell shape analyses for different time spans (Pleistocene, fossil Holocene and modern) and areas (Patagonia and Bonaerensian) showed that Elliptic Fourier analysis (EFA), Landmarks and Landmarks plus Semilandmarks (L+SL) can discriminate at generic levels: Mactra, Mulinia (Mactridae) vs. Pitar, Protothaca, Eurhomalea, Clausinella (Veneridae). L and L+SL are powerful for inter/intraspecific distinctions of Mactra. Variability of Mactra isabelleana includes the remaining nominal ‘species’ (transitional morphs). Causal environmental factors of (phenotype) variation could be addressed for modern environments (substrate, salinity and energy). Subtrigonal-inflated shells predominate in muddy, quieter, shallow mixo-polyhaline waters; ovate-elongate-compressed in sandy, poly-euhaline, deeper habitats. Differential spatial distribution (and abundance) across time responds to Late Quaternary high sea-level stands: transgressive maxima allowed higher salinity in marginal-marine areas and optimal conditions for Mactra isabelleana contrasting with scarcer records in the Mar Argentino today.     

小剂量洋地黄对急性心肌梗死PCI术后合并心力衰竭患者心率变异性的影响

目的:探讨早期应用小剂量洋地黄类药物对急性心肌梗死(Acute myocardial infarction,AMI)行经皮冠状动脉介入治疗(Percutaneous coronary intervention,PCI)术后合并心力衰竭患者心率变异性(Heart rate variability,HRV)的影响。方法:入选32例在发病24小时内接受PCI治疗且合并心力衰竭的AMI患者,再灌注后随机分为洋地黄组(西地兰0.2 mg,n=17)和对照组(生理盐水20 m L,n=15)。在用药前、用药后30分钟、用药后3小时、用药后6小时、用药后12小时、用药后24小时进行5分钟HRV分析。结果:1洋地黄组的心率在用药6小时后显著小于对照组(P0.05);2洋地黄组SDNN在用药后3小时-6小时显著大于对照组(P0.05),两组RMSSD比较无显著统计学差别(P0.05);3洋地黄组LFnorm在用药后3小时-6小时显著大于对照组(P0.05);用药3小时后,洋地黄组HFnorm显著大于对照组(P0.05),LF/HF显著小于对照组(P0.05)。结论:小剂量洋地黄可以显著降低AMI PCI术后合并心力衰竭患者的心率、逆转迷走神经与交感神经活性的失衡状态,改善HRV。     

Vegetation as self‐adaptive coastal protection: Reduction of current velocity and morphologic plasticity of a brackish marsh pioneer

By reducing current velocity, tidal marsh vegetation can diminish storm surges and storm waves. Conversely, currents often exert high mechanical stresses onto the plants and hence affect vegetation structure and plant characteristics. In our study, we aim at analysing this interaction from both angles. On the one hand, we quantify the reduction of current velocity by Bolboschoenus maritimus, and on the other hand, we identify functional traits of B. maritimus’ ramets along environmental gradients. Our results show that tidal marsh vegetation is able to buffer a large proportion of the flow velocity at currents under normal conditions. Cross‐shore current velocity decreased with distance from the marsh edge and was reduced by more than 50% after 15 m of vegetation. We were furthermore able to show that plants growing at the marsh edge had a significantly larger diameter than plants from inside the vegetation. We found a positive correlation between plant thickness and cross‐shore current which could provide an adaptive value in habitats with high mechanical stress. With the adapted morphology of plants growing at the highly exposed marsh edge, the entire vegetation belt is able to better resist the mechanical stress of high current velocities. This self‐adaptive effect thus increases the ability of B. maritimus to grow and persist in the pioneer zone and may hence better contribute to ecosystem‐based coastal protection by reducing current velocity.     

A biometrical analysis of the South AmericanElymus glaucescens complex (Poaceae: Triticeae)

Based on a simple multivariate analysis of the morphology of theAgropyron pubiflorum complex—A. patagonicum, A. antarcticum, A. fuegianum, andA. magellanicum—the variation pattern is shown to be clinal, and all taxa are included in a single, variable species. Currently the majority of species ofAgropyron is included inElymus and the correct name of this species isE. glaucescens.     

Molecular cloning of cDNA from foot-and-mouth disease virus C1-Santa Pau (C-S8). Sequence of protein-VP1-coding segment

cDNA segments copied from the RNA of foot-and-mouth disease virus (FMDV) C₁-Santa Pau (isolate C-S8) have been cloned in plasmid pBR322. A 998-bp DNA fragment, that includes the region coding for capsid protein VP1, the carboxy terminus of VP3, and the amino terminus of precursor protein p52 has been sequenced. Comparison of the nucleotide sequence with those from FMDV O₁K, A₁₀61, a₁₂ and C₃ Indaial (Kurz et al., Nucl. Acids Res. 9 (1981) 1919–1931; Kleid et al., Science 214 (1981) 1125–1129; Boothroyd et al., Gene 17 (1982) 153–161; Makoff et al., Nucl. Acids Res. 10 (1982) 8285–8295) indicates extensive variability between the corresponding gene segments, including short insertions and deletions. Base transversions are more frequent than transitions within the VP1 coding segment, but not in the sequence coding for the amino-terminal end of p52. The nucleotide sequence divergence is reflected in variability in both the primary and the predicted higher-order structures of the encoded VP1s.     

Influence of cadmium on certain biological activities in a cadmium-tolerant fungi

Aspergillus carbonarius and a strain ofPenicillium are able to grow on Harrold's agar media amended with different concentrations of cadmium chloride up to 2.5% (w/v). Considerable quantities of cadmium were absorbed by both fungi.A. carbonarius absorbed more cadmium than thePenicillium sp. did, under the same culturing conditions. In the presence of cadmium, the determined cellular contents of proteins, lipids, and carbohydrates were extraordinary high, whereas the activities of certain enzymes, lipases, amylases, and proteases were inhibited. The fungal rate of growth and sporulations were mostly suppressed. Conidiations were inhibited at lowest concentrations. At 1% Cd Cl₂,A. carbonarius produced malformed conidiophores, whereas thePenicillium sp. was less affected. At higher concentrations conidiophores production were entirely suppressed and several hyphal swellings were produced.