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Competition among adult brain cells has not been extensively researched. To investigate whether healthy glia can outcompete diseased human glia in the adult forebrain, we engrafted wild-type (WT) human glial progenitor cells (hGPCs) produced from human embryonic stem cells into the striata of adult mice that had been neonatally chimerized with mutant Huntingtin (mHTT)-expressing hGPCs. The WT hGPCs outcompeted and ultimately eliminated their human Huntington's disease (HD) counterparts, repopulating the host striata with healthy glia. Single-cell RNA sequencing revealed that WT hGPCs acquired a YAP1/MYC/E2F-defined dominant competitor phenotype upon interaction with the host HD glia. WT hGPCs also outcompeted older resident isogenic WT cells that had been transplanted neonatally, suggesting that competitive success depended primarily on the relative ages of competing populations, rather than on the presence of mHTT. These data indicate that aged and diseased human glia may be broadly replaced in adult brain by younger healthy hGPCs, suggesting a therapeutic strategy for the replacement of aged and diseased human glia. Old or diseased human glial cells in the chimeric mouse brain are eliminated by transplanted young cells. [ABSTRACT FROM AUTHOR]

Until there is an effective implementation of COVID-19 vaccination program, a robust testing strategy, along with prevention measures, will continue to be the most viable way to control disease spread. Such a strategy should rely on disparate diagnostic tests to prevent a slowdown in testing due to lack of materials and reagents imposed by supply chain problems, which happened at the beginning of the pandemic. In this study, we have established a single-tube test based on RT-LAMP that enables the visual detection of less than 100 viral genome copies of SARS-CoV-2 within 30 min. We benchmarked the assay against the gold standard test for COVID-19 diagnosis, RT-PCR, using 177 nasopharyngeal RNA samples. For viral loads above 100 copies, the RT-LAMP assay had a sensitivity of 100% and a specificity of 96.1%. Additionally, we set up a RNA extraction-free RT-LAMP test capable of detecting SARS-CoV-2 directly from saliva samples, albeit with lower sensitivity. The saliva was self-collected and the collection tube remained closed until inactivation, thereby ensuring the protection of the testing personnel. As expected, RNA extraction from saliva samples increased the sensitivity of the test. To lower the costs associated with RNA extraction, we performed this step using an alternative protocol that uses plasmid DNA extraction columns. We also produced the enzymes needed for the assay and established an in-house-made RT-LAMP test independent of specific distribution channels. Finally, we developed a new colorimetric method that allowed the detection of LAMP products by the visualization of an evident color shift, regardless of the reaction pH. [ABSTRACT FROM AUTHOR]

Cell culture models are important tools to study epileptogenesis mechanisms. The aim of this work was to characterize the spontaneous and synchronized rhythmic activity developed by cultured hippocampal neurons after transient incubation in zero Mg2+ to model Status Epilepticus. Cultured hippocampal neurons were transiently incubated with a Mg2+-free solution and the activity of neuronal networks was evaluated using single cell calcium imaging and whole-cell current clamp recordings. Here we report the development of synchronized and spontaneous [Ca2+]i transients in cultured hippocampal neurons immediately after transient incubation in a Mg2+-free solution. Spontaneous and synchronous [Ca2+]i oscillations were observed when the cells were then incubated in the presence of Mg2+. Functional studies also showed that transient incubation in Mg2+-free medium induces neuronal rhythmic burst activity that was prevented by antagonists of glutamate receptors. In conclusion, we report the development of epileptiform-like activity, characterized by spontaneous and synchronized discharges, in cultured hippocampal neurons transiently incubated in the absence of Mg2+. This model will allow studying synaptic alterations contributing to the hyperexcitability that underlies the development of seizures and will be useful in pharmacological studies for testing new drugs for the treatment of epilepsy. [ABSTRACT FROM AUTHOR]

We anatomically characterized the aerial stems of the genus Dioscorea and evaluated the use of these anatomical characteristics to better understand the taxonomy, systematics, and diversity of the component species in the neotropics. Fragments of the aerial stems of 23 species were collected for anatomical analyses utilizing conventional cytohistological techniques. Stem anatomy did not support the subgenera and neotropical sections of Dioscorea, although D. sect. Monadelpha demonstrated similar anatomical characteristics with the representatives analyzed in the present work, supporting the possible monophyletism of that section. Some New World species demonstrated characteristics described earlier for Old World species, such as two phloem units internal to the large-diameter vessels. New characters to the vascularization of new world species are described, as a single ring of vascular bundles, intercalating common and cauline bundles. Tylosoids and actinocytic stomata were the first time reported in Dioscorea, and the vascular patterns are revisited with a systematic approach. [ABSTRACT FROM AUTHOR]

The detection and analysis of metabolically active microorganisms are useful to determine those directly involved in the biodeterioration of cultural heritage (CH). Fluorescence in situ hybridization with oligonucleotide probes targeted at rRNA (RNA-FISH) has demonstrated to be a powerful tool for signaling them. However, more efforts are required for the technique to become a vital tool for the analysis of CH's microbiological communities. Simultaneous analysis of microorganisms belonging to different kingdoms, by RNA-FISH in-suspension approach, could represent an important progress: it could open the door for the future use of the technique to analyze the microbial communities by flow cytometry, which has shown to be a potent tool in environmental microbiology. Thus, in this work, various already implemented in-suspension RNA-FISH protocols for ex situ analysis of yeast and bacteria were investigated and adapted for allowing the simultaneous detection of these types of microorganisms. A deep investigation of the factors that can affect the results was carried out, focusing particular attention on the selection of the fluorochromes used for labelling the probe set. The resultant protocol, involving the use of EUK516-6-FAM/EUB338-Cy3 probes combination, was validated using artificial consortia and gave positive preliminary results when applied in samples from a real case study: the Paleolithic archaeological site of Escoural Cave (Alentejo, Portugal). This approach represents the first dual-staining RNA-FISH in-suspension protocol developed and applied for the simultaneous investigation of CH biodeteriogenic agents belonging to different kingdoms. [ABSTRACT FROM AUTHOR]

In this paper we specifically address the constraint of energy consumption related to wireless sensor networks deployed at remote regions where the geographical access is complicated and consequently the maintenance routines seldom occurs. This research proposes an energy management method for environmental monitoring at the Amazonian Basin, where the interval between maintenance routines is greater than 6 months and the geographical location constrains the access to the sensor nodes. The proposed method is based on the duty cycling technique and aims to extend the sensor node lifespan in case of its external power source fails or its power consumption increases due to damages in sensor node devices. The management energy algorithm embedded into the sensor node employs the Shepherd Equation to simulate curves of battery discharge for each power consumption condition and thus it enables to estimate accurately the lifespan of a sensor node. Therefore, the sensor node is aware of its available energy and was programmed to react to it by switching between predefined operating modes to save energy and prolong as much as possible its lifespan. The Sensor Energy Management Method (SEMM) ensures that sensor nodes are operational throughout maintenance periods so that at least data acquisition tasks are performed to guarantee historical data sets essential to hydrological forecasts. A sensor node prototype was built and the SEMM was validated by a number of indoors experiments. The sensor node lifetime was increased by 20 % when the proposed method was compared to a conventional energy use. [ABSTRACT FROM AUTHOR]

Bacterial resistance to antibiotics has become a public health issue. Over the years, pathogenic organisms with resistance traits have been studied due to the threat they pose to human well-being. However, several studies raised awareness to the often disregarded importance of environmental bacteria as sources of resistance mechanisms. In this work, we analyze the diversity of antibiotic-resistant bacteria occurring in aquatic environments of the state of Rio de Janeiro, Brazil, that are subjected to distinct degrees of anthropogenic impacts. We access the diversity of aquatic bacteria capable of growing in increasing ampicillin concentrations through 16S rRNA gene libraries. This analysis is complemented by the characterization of antibiotic resistance profiles of isolates obtained from urban aquatic environments. We detect communities capable of tolerating antibiotic concentrations up to 600 times higher than the clinical levels. Among the resistant organisms are included potentially pathogenic species, some of them classified as multiresistant. Our results extend the knowledge of the diversity of antibiotic resistance among environmental microorganisms and provide evidence that the diversity of drug-resistant bacteria in aquatic habitats can be influenced by pollution. [ABSTRACT FROM AUTHOR]

The Marantaceae family is composed of 550 species of pantropical distribution, with a strong clustering in the Neotropics. Although the family forms a monophyletic group, the circumscription of genera and consequently its phylogenetic relationships are not sufficiently understood. Its species produces silica phytoliths in varied forms, ornamentation and distribution in leaves, and these silica deposits are considered important in vegetable physiology and taxonomy. We have conducted the morphological characterisation of phytoliths and their distribution in foliar blades of Neotropical Marantaceae genera, evaluating the use of such characters to support the morphological delimitation of the genera and the physiological aspects of the family's adaptation to rainforests. Phytoliths of 22 species of 12 genera, namely Calathea, Ctenanthe, Goeppertia, Hylaeanthe, Ischnosiphon, Koernickanthe, Maranta, Monotagma, Myrosma, Saranthe, Stromanthe and Thalia, were analysed using light and scanning electron microscopes. When comparing Neotropical species to those of the old world, one can observe the family's homogeneity by the presence of two morphotypes in the foliar blade, the globular and the irregular, as well as stegmata associated with the fibres. However, two distinguishing features have been identified in these Neotropical species: (1) a new morphotype, the cylindroid, located in the mesophyll, (2) intra- and extracellular amorphous silica deposits associated with the stomata, which play an important role in the restriction of transpiration. In addition, the form, size and distribution of the silica deposits appear conservative in all analysed samples, which makes them useful in the morphological characterisation of the genera and species, and consequently, in the taxonomic circumscription of the Marantaceae. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to assess the association between mandibular torus and its size with the presence of bruxism and other variables related to parafunctional activity (e.g. anxiety, wear facets, self-perception and family members perception of bruxism, headache and/or muscle fatigue). Materials and methods: Subjects included in the study were examined and interviewed and they completed a questionnaire on anxiety. The subjects were divided into two paired groups according to age and gender with the case group formed by 100 individuals having mandibular torus and a control group formed by individuals without. Each group had 33 men and 67 women with ages ranging from 20 to 62 years old (mean age 41 years). Results: The results showed that patients with bruxism are 4 times more likely to have mandibular torus compared to those patients without bruxism. The presence of wear facets increases the risk of mandibular torus by 20 times. Only the variables bruxism and wear facets had relatively strong correlations with the size of mandibular torus. Conclusions: There was a strong association between mandibular torus and presence of both bruxism and wear facets. Such correlations were positive thus indicating an important trend in which a higher degree of bruxism is related to an increased size of the mandibular torus. The other variables, despite their statistical significance, had poor correlations and thus were not found to be clinically important. [ABSTRACT FROM AUTHOR]

A nanodispersion of surface-functionalized fumed silica was incorporated into an acrylic paint formulation. SEM imaging indicated good dispersion of silica within the polymer matrix. This hybrid coating showed significantly lower dirt pick-up than the equivalent paint formulation without nanosilica additive, towards both organic and inorganic ashes. Washing with running water further decreases dirt retention. This self-cleaning performance remained unchanged after several dirt/washing cycles, during a 1-month period. Surface hardness measurements indicated no significant differences between the original and composite paint films. The lower dirt pick-up was attributed to nanoroughness created by the nanosilica particles present in the film. [ABSTRACT FROM AUTHOR]

Previous morphological analysis has indicated that subgenus Meconostigma was the basal group of the genus and sister group of a clade formed by subgenera Philodendron and Pteromischum. However, recent molecular analysis suggests Pteromischum is the sister group of the clade Philodendron and Meconostigma. The objective of this work was to anatomically describe the stem of Philodendron, searching for possible synapomorphies for the three currently accepted subgenera, and thus give support to one of the two phylogenetic hypotheses, and to contribute new and updated information about characters relevant to the taxonomy of the group. Anatomical data were obtained from 14 species of Philodendron. The main conclusions of our study were recognition of a sclerified hypodermis and storied cork in Philodendron and verification of the absence of amphivasal bundles, the presence of which was previously suggested for the genus by French and Tomlinson. The presence of a branched root vascular plexus in Meconostigma and Philodendron gives support to the phylogenetic hypothesis in which those two subgenera form a monophyletic clade. The unistratified and sclerified hypodermis, only simple vascular bundles within the periphery of the central cylinder, and a connection through a fibrous sheath between them were considered apomorphic characters of Pteromischum. [ABSTRACT FROM AUTHOR]

A culture-independent molecular phylogenetic analysis was carried out to study for the first time the diversity of bacterial ammonia monooxygenase subunit A ( amoA) and nitrogenase reductase subunit H ( nifH) genes from Urca inlet at Guanabara Bay in Rio de Janeiro, Brazil. Most bacterial amoA and nifH sequences exhibited identities of less than 95% to those in the GenBank database revealing that novel ammonia-oxidizing bacteria and nitrogen-fixing microorganisms may exist in this tropical marine environment. The observation of a large number of clones related to uncultured bacteria also indicates the necessity to describe these microorganisms and to develop new cultivation methodologies. [ABSTRACT FROM AUTHOR]

Carbon nanofibers were synthesized on graphite felt substrate by catalytic decomposition of ethane. The preshaped material was efficiently used as catalyst support for the active phase NiS in the direct oxidation of HS into elemental sulfur. The catalyst was extremely active, selective, and stable at 60 °C in a fixed bed reactor due to the high resistance of carbon nanofiber based catalyst to the solid sulfur loading. This is explained by the specific mode of sulfur deposition, involving the role of water in the sulfur transport and the hydrophobic nature of the support. Graphical Abstract: [Figure not available: see fulltext.][Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The bacterioplankton diversity of coastal waters along a latitudinal gradient between Puerto Rico and Argentina was analyzed using a total of 134,197 high-quality sequences from the V6 hypervariable region of the small-subunit ribosomal RNA gene (16S rRNA) (mean length of 60 nt). Most of the OTUs were identified into Proteobacteria, Bacteriodetes, Cyanobacteria, and Actinobacteria, corresponding to approx. 80% of the total number of sequences. The number of OTUs corresponding to species varied between 937 and 1946 in the seven locations. Proteobacteria appeared at high frequency in the seven locations. An enrichment of Cyanobacteria was observed in Puerto Rico, whereas an enrichment of Bacteroidetes was detected in the Argentinian shelf and Uruguayan coastal lagoons. The highest number of sequences of Actinobacteria and Acidobacteria were obtained in the Amazon estuary mouth. The rarefaction curves and Good coverage estimator for species diversity suggested a significant coverage, with values ranging between 92 and 97% for Good coverage. Conserved taxa corresponded to aprox. 52% of all sequences. This study suggests that human-contaminated environments may influence bacterioplankton diversity. [ABSTRACT FROM AUTHOR]

Background, aim, and scope Pulp and paper production is one of the most important Portuguese economic activities. Mostly based on eucalyptus (Eucalyptus globulus), nearly 70% of the pulp produced is exported, mainly to the European Union. The aim of this paper is to compare the environmental impacts of the production of Portuguese printing and writing paper based on eucalyptus with those from the production of paper from industrial hemp (Cannabis sativa). Materials and methods We have used a life cycle assessment approach to compare both types of paper. The functional unit used was a ton of white printing and writing paper. Data was mostly derived from the Portuguese literature for eucalyptus and from scientific literature for hemp. The impact categories/indicators taken into account were global warming, photochemical oxidant formation (summer smog), acidification, eutrophication, and direct land use. Results and discussion Industrial hemp presents higher environmental impacts than eucalyptus paper in all environmental categories analyzed. The main differences are in the crop and the pulp production stages. This is because hemp makes use of higher number of mechanical operations and larger amounts of fertilizer in the former and larger amounts of chemical additives in the latter. Conclusions There is scope for improving industrial hemp paper production. We present some suggestions on how to reduce some of the environmental impacts identified for hemp, so that the pulp and paper industry can continue its progress towards a more environmentally friendly paper production. Recommendations and perspectives New studies could be based on the alternatives presented throughout the paper for improving hemp paper. Further studies should incorporate analyses on water consumption, soil erosion, soil nutrient depletion, and impacts on biodiversity. [ABSTRACT FROM AUTHOR]

Mining of metallic sulfide ore produces acidic water with high metal concentrations that have harmful consequences for aquatic life. To understand the composition and structure of microbial communities in acid mine drainage (AMD) waters associated with Zn mine tailings, molecular diversity of 16S genes was examined using a PCR, cloning, and sequencing approach. A total of 78 operational taxonomic units (OTUs) were obtained from samples collected at five different sites in and around mining residues in Sepetiba Bay, Brazil. We analyzed metal concentration, physical, chemical, and microbiological parameters related to prokaryotic diversity in low metal impacted compared to highly polluted environments with Zn at level of gram per liter and Cd–Pb at level of microgram per liter. Application of molecular methods for community structure analyses showed that Archaea and Bacteria groups present a phylogenetic relationship with uncultured environmental organisms. Phylogenetic analysis revealed that bacteria present at the five sites fell into seven known divisions, α- Proteobacteria (13.4%), β- Proteobacteria (16.3%), γ- Proteobacteria (4.3%), Sphingobacteriales (4.3%), Actinobacteria (3.2%) Acidobacteria (2.1%), Cyanobacteria (11.9%), and unclassified bacteria (44.5%). Almost all archaeal clones were related to uncultivated Crenarchaeota species, which were shared between high impacted and low impacted waters. Rarefaction curves showed that bacterial groups are more diverse than archaeal groups while the overall prokaryotic biodiversity is lower in high metal impacted environments than in less polluted habitats. Knowledge of this microbial community structure will help in understanding prokaryotic diversity, biogeography, and the role of microorganisms in zinc smelting AMD generation and perhaps it may be exploited for environmental remediation procedures in this area. [ABSTRACT FROM AUTHOR]

Several species of the genus Rhipsalis (Cactaceae) are extremely important as ornamentals and are endangered in their natural habitat. However, only a few studies have addressed its taxonomy, morphology (including anatomy), phylogeny and evolutionary history. Consequently, the limited knowledge of the genus coupled with the problematic delimitation of species had led to problems in the identification of taxa. In the current work six species of Rhipsalis, R. cereoides, R. elliptica, R. grandiflora, R. paradoxa, R. pentaptera and R. teres were studied to evaluate the relevance of anatomical characters for the taxonomy of the genus. An anatomical characterization of the primary structure of the stem of Rhipsalis is provided highlighting the differences between species. Features of the stem epidermis are found to discriminate best between species and therefore provide clear and useful characters for the separation of species. [ABSTRACT FROM AUTHOR]

In this study we performed a survey of the bacterial communities associated with the Western Atlantic demosponges Hymeniacidon heliophila and Polymastia janeirensis, based on 16S rRNA sequencing and transmission electron microscopy (TEM). We compared diversity and composition of the sponge-associated bacteria to those of environmental bacteria, represented by free-living bacterioplankton and by bacteria attached to organic particulate matter in superficial sediments. Partial bacterial 16S rRNA sequences from seawater, sediment, and sponges were retrieved by PCR, cloning, and sequencing. Sequences were subjected to rarefaction analyses, phylogenetic tree construction, and LIBSHUFF quantitative statistics to verify coverage and similarity between libraries. Community structure of the free-living bacterioplankton was phylogenetically different from that of the sponge-associated bacterial assemblages. On the other hand, some sediment-attached bacteria were also found in the sponge bacterial community, indicating that sponges may incorporate bacteria together with sediment particles. Rare and few prokaryotic morphotypes were found in TEM analyses of sponge mesohyl matrix of both species. Molecular data indicate that bacterial richness and diversity decreases from bacterioplankton, to particulate organic sediment, and to H. heliophila and P. janeirensis. Sponges from Rio de Janeiro harbor a pool of novel and exclusive sponge-associated bacterial taxa. Sponge-associated bacterial communities are composed of both taxons shared by many sponge groups and by species-specific bacteria. [ABSTRACT FROM AUTHOR]

Guanabara Bay is an eutrophic estuarine system located in a humid tropical region surrounded by the second largest metropolitan area of Brazil. This study explores the contrasting environmental chemistry and microbiological parameters that influence the archaeaplankton diversity in a pollution gradient in Guanabara Bay ecosystem. The environments sampled ranged from completely anoxic waters in a polluted inner channel to the adjacent, relatively pristine, coastal Atlantic Ocean. Partial archaeal 16S rDNA sequences in water samples were retrieved by polymerase chain reaction (PCR) and analyzed using denaturing gradient gel electrophoresis (DGGE), cloning, and sequencing. Sequences were subjected to phylogenetic and diversity analyses. Community structure of the free-living archaeal assemblages was different from that of the particle-attached archaea according to DGGE. Gene libraries revealed that phylotype identification was consistent with environmental setting. Archaeal phylotypes found in polluted anoxic waters and in more pristine waters were closely related to organisms that have previously been found in these environments. However, inner bay archaea were related to organisms found in oil, industrial wastes, and sewage, implying that water pollution controls archaea communities in this system. The detection of a substantial number of uncultured phylotypes suggests that Guanabara Bay harbors a pool of novel archaeaplankton taxa. [ABSTRACT FROM AUTHOR]

The taxonomic relationships among the four genera of the Atelidae family, Alouatta (Howler), Ateles (Spider), Lagothrix (Woolly) and Brachyteles (Muriqui), have been the subject of great debate. In general, almost all authors agree with the assignment of Howler monkeys as the basal genus, either in its own tribe Alouattini or in the subfamily Alouattinae, but they disagree on the associations among the other members of the family. Muriquis have been grouped with Spider monkeys based on the fact that they share various behavioral and morphological characteristics. Cladistic analyses using morphological, biochemical, karyotype and behavioral characteristics depicted a phylogenetic tree that places Howler as the basal genus and the remaining genera in an unresolved politomy. More recent studies using molecular data have suggested that Muriqui and Woolly monkeys are sister groups. However, a recent study based on nuclear and mtDNA argued that politomy is what best represents the relationships among Spider, Woolly and Muriqui. To contribute to this debate we have added new data from two nuclear genes, Transferrin and von Willebrand Factor, and using an alignment of 17,997 bp we demonstrate that a total analysis strongly supports the Muriqui-Woolly clade. A gene-to-gene approach showed that four of the eight nuclear genes provide support for the Muriqui-Woolly clade, two strongly and two moderately, while none of the eight genes provide support for any alternative arrangement. The mitochondrial genes were not able to resolve the politomy. A possible reason for the difficulty in resolving atelid relationships may be the short period of time separating each cladogenetic event in the evolutionary process that shaped this family. [ABSTRACT FROM AUTHOR]

The aim of this work is to report the catalytic performances of iridium supported on carbon nanofibre with macroscopic shaping in the catalytic decomposition of hydrazine. The performances obtained are compared to those of the commercial catalyst Shell 405. Catalytic experiments are carried out in a 2 N microthruster. The carbon nanofibre based catalyst shows better activity performances than the commercial one due to its high external surface area and its high thermal conductivity. [ABSTRACT FROM AUTHOR]

The leaf micromorphology of Antarctic pearlwort, Colobanthus quitensis (Kunth) Bartl. was analyzed. Plants were collected at King George Island (62°5′S, 58°23′W). Leaves were analyzed by optical and scanning electron microscopy, and quantitative analyses performed on leaf tissues and their internal geometry. C. quitensis leaves are ca. 588 μm thick, and composed of palisade and spongy parenchyma, respectively ca. 171 and 312 μm thick. Cuticles are thin and cover short epidermal cells. The central vein is surrounded by two bundles of achlorophyllous cells. Sclerenchymatic tissues are poorly developed. SEM analysis reveals faint striations over leaf surfaces. Stomata are present on both surfaces, but restricted to the leaf margins on the abaxial side. The ratio of mesophyll cell surface area per unit leaf area (Ames/A) is 34.2. The number of cells per cross-sectional area occupied was 24% higher for the palisade than for the spongy tissue, which determines a higher cell surface area per cross-sectional area for the former tissue. The authors correlate these results to plant ecological distribution in Antarctica and to water and carbon economy. [ABSTRACT FROM AUTHOR]

study was made of polysaccharides and glycosphingolipids isolated from Aspergillus fumigatus grown in media supplemented with human serum from healthy donors. Fractionation of Cetavlon-precipitated polysaccharides on Sephacryl S-400 gave rise to an excluded fraction (Fraction I) with molecular weight of >400 kDa and an included peak (Fraction II) with an average molecular weight of 30-80 kDa. Fraction I comprises about 5% of total polysaccharide and was identified as a glycogen-like molecule. Its structure was deduced from methylation data, treatment with amyloglucosidase, a red-brown coloration produced with an iodine solution and by H and C-NMR spectroscopy. It was previously suggested that higher amounts of glycogen-like polysaccharide (20%) were present in A. fumigatus grown in serum-free medium. Fraction II was identified as a galactomannan and was the main polysaccharide of A. fumigatus grown in serum-supplemented medium. Its structure was elucidated mainly by C-NMR spectroscopy combined with partial acetolysis and methylation analysis. The C-NMR spectrum of the galactomannan showed a much greater complexity in the β-d-galf and α-d-manp C-1 regions, than was evident for galactomannan from serum-free cultures previously described, reflecting differences in the glycosylation pattern, stimulated in serum-supplemented medium. No differences in A. fumigatus glycosphingolipid could be detected between serum-containing and serum-free growth conditions. Our results demonstrate that the change in polysaccharide structure is a more specific response to the altered growth conditions and not merely a symptom of more general changes. [ABSTRACT FROM AUTHOR]