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[In vitro studies of modification of mucociliary clearance by guinea pig tracheas by exposure to air pollutants of sulfur or nitrogen dioxide].

We studied the effect of sulfur dioxide (SO2) and nitrogen dioxide (NO2) on mucociliary activity (MCA) and ciliary beat frequency (CBF) in 63 guinea pig tracheas. The tracheas were placed in a gas cylinder and exposed for 30 minutes to SO2 concentrations ranging from 2.5 to 12.5 ppm or to NO2 concentrations ranging from 3.0 to 15.0 ppm. Control experiments were performed with exposure of the tracheas to synthetic air. MCA was measured by recording the light reflected from ciliated mucous membranes using an infrared barcode reader and CBF using video-interference microscopy. The exposure to 2.5 ppm SO2 caused a reduction in mean MCA of 63% and no significant changes in CBF. Higher SO2 concentrations caused a further impairment of MCA as well as a dose-dependent decrease in CBF. 10.0 or 12.5 ppm SO2 induced a decrease from baseline values to approximately 20% in MCA and to roughly 30% in mean CBF. The exposure to NO2 at concentrations ranging from 3.0 to 15.0 ppm did not induce any changes in MCA or CBF of the guinea pig tracheas. Our results show that exposure to SO2 for 30 minutes is able to depress the mucociliary clearance of guinea pig tracheas, whereas the exposure to equivalent NO2 concentrations for the same time do not alter the mucociliary transport.

Air Pollutants↗

[Application of DNA fingerprinting to obstetrics and gynecology].

Restriction fragment length polymorphisms (RFLP) are variations in the size of restriction fragments of genomic DNA that hybridize to specific probes. They are the consequence of changes in primary DNA sequences, most of which result from small-scale changes in DNA. Recently minisatellite DNA probes that detect many regions of great variability within the human genome have been described. Minisatellite probes consist of multiple repeated copies of a common 10-15 base pair core sequence. On hybridization to restriction enzyme digests of human DNA, they simultaneously detect many highly polymorphic minisatellites at different loci in the genome, and produce band patterns that are individual specific. The band patterns are called "DNA fingerprints" or "DNA barcode" which can be used for individual identification on forensic and legal medicine. In addition to forensic and legal medicine, DNA fingerprinting can be used in both basic research and clinical examination of obstetrics and gynecology. The RFLP bands in DNA fingerprinting are inherited as single Mendelian co-dominants and we can use such minisatellite DNA probe for the determination of zygosity in multiple pregnancy. This probe can be used for the determination of androgenesis as a cause of complete hydatidiform mole. Each polymorphic band in molar tissues could be identified as being of paternal but not maternal origin. Some polymorphic bands of paternal origin were not observed in molar tissues, indicating that endoreduplication of a normal haploid sperm or fertilization by dispermy to an anuclear oocyte with no effective genome could be the cause of complete hydatidiform mole (androgenesis).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Automated HPLC screening of newborns for sickle cell anemia and other hemoglobinopathies.

Automated HPLC is used to test dried blood-spot specimens from newborns for hemoglobins (Hb) F, A, S, C, E, and D. We present the method and report on its performance determined during >4 years of testing 2.5 x 10(6) newborns. The method features automated derivation of presumptive phenotypes; quantitative quality control and proficiency testing; throughput of one specimen per minute; small sample volume; hemoglobin concentrations quantified with an interlaboratory CV of 14-18%; retention times with interlaboratory CV of <2% and matching, within +/- 0.03 min, of laboratories and reagent lots; control of peak resolution; 0.5% detection limit for Hb S and C, and 1.0% for Hb F, A, E, and D; few interferences; and negligible background and carryover. Shortcomings of the method are the absence of microplate barcode identification and the need for manually pipetting the sample eluate into the microplate.

Anemia, Sickle Cell↗

DNA fiber fluorescence in situ hybridization analysis of immunoglobulin class switching in B-cell neoplasia: aberrant CH gene rearrangements in follicle center-cell lymphoma.

Immunoglobulin class switching usually involves deletion of part of the immunoglobulin CH region. By DNA fiber fluorescence in situ hybridization (FISH) with a barcode of probes covering the DH, JH, and CH genes, the configuration of the entire CH region can be visualized on single DNA molecules. Using this technique, we have studied class switching in three types of B-cell neoplasia, mantle-cell lymphoma (MCL), follicular lymphoma (FL) and hairy cell leukemia (HCL), representing B cells in, respectively, pregerminal center, germinal center, and postgerminal center stages of development. In MCL and FL, simultaneous detection of the t(11;14) and t(14;18) breakpoint with probes for the BCL-1 and BCL-2 loci, respectively, allowed differentiation between productive and nonproductive alleles. In none of 10 MCL cases was class switching detected. In 21 HCL, all nonimmunoglobulin M (IgM) cases had class-switch deletion consistent with the expressed isotype on at least one allele. In FL, however, a peculiar pattern of CH rearrangement was observed. In IgM expressing FL, the translocated alleles had switched in 11 of 13 cases, and the nontranslocated allele showed complex rearrangements downstream from the Cmu-Cdelta genes in 9 of 13 cases. These downstream rearrangements may reflect tumor-specific deregulation of the class-switch machinery. All seven immunoglobulin G (IgG) expressing FL showed class switching on both alleles. Fiber FISH analysis also showed several polymorphisms. The most frequent one, present on 38% of all analyzed alleles, consisted of an extra Cgamma gene or pseudogene in the 3' cluster.

B-Lymphocyte Subsets↗

Recurrent and niche-specific functional bacteriome of maize hybrid revealed by integrated metabarcoding and culturomics.

The plant microbiome plays a pivotal role in plant survival in natural habitats by facilitating nutrient acquisition, stress adaptation, and disease suppression, while also offering opportunities to enhance crop productivity and climate resilience. However, the distribution of persistent and culturable bacteriome across maize-associated niches and their functional potential remain poorly resolved. This study integrated metagenomic next-generation sequencing (mNGS-based metabarcoding) and culturomics to characterise the maize-associated bacteriome of bulk soil, rhizoplane, phylloplane, and cob of the maize hybrid PHM-1 under contrasting cropping and tillage systems, and to identify recurrent and agriculturally promising bacteriome components. The bacteriome exhibited pronounced niche-specific structuring, whereas overall bacterial community composition did not differ significantly across cropping and tillage treatments (ANOSIM, R&#x2009;=&#x2009;0.038, p&#x2009;=&#x2009;0.306). Proteobacteria predominated in the culturable bacteriome (69-84%; mean, 76.2%) but accounted for only 1% of the total bacteriome, whereas Patescibacteria and Firmicutes were relatively enriched. Niche-specific dominance was evident, with Pantoea accounting for 40.79% of the total and 56.27% of the culturable phylloplane bacteriome under cereal monocropping, while Serratia represented 31.59% and 59.40% of the total and culturable cob bacteriomes, respectively. Across niches, mNGS captured substantially greater bacteriome diversity, particularly uncultured and unidentified taxa in soil-associated compartments, whereas culturomics recovered a narrower but functionally accessible fraction. Culturomics yielded 99 isolates representing 32 species across 12 genera, including six genera shared with the mNGS-derived recurrent bacteriome: Bacillus, Enterobacter, Pantoea, Pseudomonas, Serratia, and Stenotrophomonas. Functional screening identified strong biocontrol and plant-beneficial traits among core-associated isolates. Pseudomonas oryzihabitans ZM-DL-PA10 inhibited Rhizoctonia solani, Macrophomina phaseolina, and Bipolaris maydis by up to 40.6%, 43.9%, and 45.2%, respectively, through secreted and volatile metabolites; exhibited P, K, and Zn solubilisation; and produced IAA and siderophores. It also recorded the lowest B. maydis disease index (ADI) of 1.00. Pantoea ananatis ZM-BH-EA4 showed 52.4% and 68.5% inhibition of R. solani and B. maydis, respectively, through volatile metabolites. Collectively, the integration of mNGS and culturomics revealed a strongly compartmentalised maize bacteriome and identified recurrent, culturable, and functionally promising bacterial taxa, providing a targeted resource for microbiome-based crop protection and climate-resilient maize production.

Zea mays↗

"Not flying solo": phylogenetic identification and life-cycle insights of larval cestodes in the European flying squid Todarodes sagittatus (Cephalopoda: Ommastrephidae).

The European flying squid Todarodes sagittatus Lamarck is a widely distributed ommastrephid cephalopod in the Northeast Atlantic and Mediterranean Sea, yet its parasite fauna remains poorly documented in the&#xa0;Mediterranean Sea. In this study, two cestode larvae species infecting T. sagittatus from the Algerian coast (Western Mediterranean) were investigated using an integrative approach combining morphological observations and molecular analyses. A total of 63 squids were examined for parasitic infection. Cestodes in plerocercoid stage were detected in 31 individuals (prevalence of 46%), primarily located within the gastrointestinal tract, including the stomach, intestine, and caecum. Morphological features of the larvae were consistent with members of the order Phyllobothriidea but did not allow identification to the species level. Molecular analysis of the D1-D3 region of the 28S rDNA revealed two distinct larval lineages belonging to the genus Crossobothrium Linton, 1889. One lineage showed 100% sequence identity with the adult cestode Crossobothrium dohrnii (Oerley, 1885), a parasite of hexanchid sharks, confirming the identity of these larvae as plerocercoids of C. dohrnii. The second lineage clustered within the Crossobothrium clade but could not be assigned to a known species and is therefore referred to as Crossobothrium sp. The occurrence of these larvae in T. sagittatus, together with ecological data on squid diet and predator-prey relationships, suggests that this cephalopod acts as an intermediate or paratenic host in the life cycle of hexanchid cestodes. Infection likely occurs through predation on crustaceans acting as first intermediate hosts, while transmission to definitive hosts occurs when infected squids are consumed by sharks. These findings provide the first molecular identification of cestode larvae from T. sagittatus in the Mediterranean and highlight the important role of ommastrephid squids in the trophic transmission of elasmobranch parasites in pelagic ecosystems.

Crossobothrium↗

Common to rare transfer learning (CORAL) enables inference and prediction for a quarter million rare Malagasy arthropods.

DNA-based biodiversity surveys result in massive-scale data, including up to millions of species-of which, most are rare. Making the most of such data for inference and prediction requires modeling approaches that can relate species occurrences to environmental and spatial predictors, while incorporating information about their taxonomic or phylogenetic placement. Even if the scalability of joint species distribution models to large communities has greatly advanced, incorporating hundreds of thousands of species has not been feasible to date, leading to compromised analyses. Here we present a 'common to rare transfer learning' (CORAL) approach, based on borrowing information from the common species to enable statistically and computationally efficient modeling of both common and rare species. We illustrate that CORAL leads to much improved prediction and inference in the context of DNA metabarcoding data from Madagascar, comprising 255,188 arthropod species detected in 2,874 samples.

Animals↗

NanoASV: a snakemake workflow for reproducible field-based Nanopore full-length 16S metabarcoding amplicon data analysis.

SUMMARY: NanoASV is a conda environment and snakemake-based workflow using state-of-the-art bioinformatics software to process full-length SSU rRNA (16S/18S) amplicons acquired with Oxford Nanopore Sequencing technology. Its strength lies in reproducibility, portability, and the possibility to run offline, allowing in-field analysis. It can be installed on the Nanopore MK1C sequencing device and process data locally. AVAILABILITY AND IMPLEMENTATION: Source code and documentation are freely available at https://github.com/ImagoXV/NanoASV and Zenodo archive at https://doi.org/10.5281/zenodo.14730742.

Software↗

Predicting coarse-grained representations of biogeochemical cycles from metabarcoding data.

MOTIVATION: Taxonomic analysis of environmental microbial communities is now routinely performed thanks to advances in DNA sequencing. Determining the role of these communities in global biogeochemical cycles requires the identification of their metabolic functions, such as hydrogen oxidation, sulfur reduction, and carbon fixation. These functions can be directly inferred from metagenomics data, but in many environmental applications metabarcoding is still the method of choice. The reconstruction of metabolic functions from metabarcoding data and their integration into coarse-grained representations of biogeochemical cycles remains a difficult bioinformatics problem today. RESULTS: We developed a pipeline, called Tabigecy, which exploits taxonomic affiliations to predict metabolic functions constituting biogeochemical cycles. In a first step, Tabigecy uses the tool EsMeCaTa to predict consensus proteomes from input affiliations. To optimize this process, we generated a precomputed database containing information about 2404 taxa from UniProt. The consensus proteomes are searched using bigecyhmm, a newly developed Python package relying on Hidden Markov Models to identify key enzymes involved in metabolic function of biogeochemical cycles. The metabolic functions are then projected on coarse-grained representation of the cycles. We applied Tabigecy to two salt cavern datasets and validated its predictions with microbial activity and hydrochemistry measurements performed on the samples. The results highlight the utility of the approach to investigate the impact of microbial communities on biogeochemical processes. AVAILABILITY AND IMPLEMENTATION: The Tabigecy pipeline is available at https://github.com/ArnaudBelcour/tabigecy. The Python package bigecyhmm and the precomputed EsMeCaTa database are also separately available at https://github.com/ArnaudBelcour/bigecyhmm and https://doi.org/10.5281/zenodo.13354073, respectively.

Metagenomics↗

Bycatch in a bottle: what taxa are recoverable from metabarcoding DNA in historical invertebrate collection preservative fluid?

Natural history museum collections are invaluable repositories of biodiversity, offering insights into life on Earth. Genomic approaches provide powerful tools to characterize biodiversity in these collections. However using these collections for genomics without damaging specimens is a challenge. Here, we develop and test non-destructive DNA metabarcoding methods to capture biodiversity from the preservative fluids of archived insect collections ('Bycatch'). We optimized workflows for extracting and amplifying the partial CO1 locus (CO1) and fungal ITS1 locus from ethanol-based preservative fluids, validating ethanol preparation methods, comparing DNA extraction kits, and refining PCR protocols. Our results demonstrate that from museum collections with low DNA yields, CO1 and fungal ITS1 loci can often be recovered from preservative fluids, and we present detailed methodology and workflows. We test metabarcoding success to recover taxa in several museum collections ranging in age and storage condition. This is to support the State of California's effort to catalog and sequence all insects and fungi, building baselines of California biodiversity with help from museum collections. Lastly, we investigate the complementarity of metabarcoding water versus ethanol and morphological identifications aimed to capture benthic macroinvertebrate biodiversity in streams. Our findings highlight that DNA metabarcoding of the preservative fluid is a non-destructive tool for capturing biodiversity in historical specimens, but there are limitations on the overlaps between DNA results and physical contents, where morphological identification still reigns in taxon counts, but metabarcoding sometimes provides more taxonomic resolution, and can be used to track DNA from other organisms such as fungi beyond the directly surveyed specimens.

Animals↗

The role of stochasticity in fungal community assembly: explaining apparent stochasticity with field experiments.

Stochasticity is a main process in community assembly. However, experimental studies rarely target stochasticity in natural communities, and hence experimental validation of stochasticity estimates in observational studies is lacking. Here, we combine experimental and observational data to unravel the role of stochasticity in the assembly of wood-inhabiting fungi. We carried out a replicated field experiment where the natural colonization of a focal fungal species was simulated through inoculation, and the local fungal communities were monitored through DNA metabarcoding before and after the inoculations. The amount of stochasticity in fungal colonization was less pronounced than expected from the amount of unpredictability in observational data, suggesting that stochasticity may play a smaller role in fungal occurrence than previously anticipated, or that it may be a stronger influence in the dispersal and establishment phases than in colonization per se. Stochasticity was more prominent in the initial phase of community succession, with the earliest successional stage involving a higher level of stochasticity than the later stage after 2 years. We conclude that experimentally measuring the role of stochasticity in community assembly is feasible for species-rich communities under natural conditions and highlight the importance of experimentally testing the accuracy of stochasticity estimates based on observational data.

Stochastic Processes↗

Getting to the Core of the Matter-Assessing the Role of Replication in Metabarcoding-Based sedaDNA.

Replication is central to most experimental and sampling designs, increasing inferential power and capturing fine-scale data heterogeneity. However, its importance remains poorly evaluated in some ecological and evolutionary settings. This is the case of metabarcoding studies using DNA recovered from sedimentary archives, in which biological signals integrate ecological information through depositional and burial processes, yet are commonly inferred from a single sediment core per site. Here, we evaluated the effect of different types of replication using sedimentary DNA metabarcoding data from two genetic markers (mitochondrial COI and nuclear 18S) using a nested sampling design. The design included three intertidal sites, three spatially separated sediment cores per site (biological replicates), two sediment horizons per core, and eight PCR (technical) replicates per sediment sample. Variance partitioning showed that site identity and sediment age group together explained >&#x2009;70% of the variation in beta diversity, indicating that among-site spatial and stratigraphic differences were the dominant drivers of community composition. PERMANOVA likewise identified non-significant effects of biological replication. Among PCR replicates from the same sediment sample, richness varied substantially, whereas Shannon diversity was more consistent. Despite this variability, differences in community composition among technical replicates remained smaller than those associated with biological replication or site identity, indicating a limited influence on broader ecological patterns. Community composition was highly similar among replicate cores within sites, consistent with stratigraphic coherence. These results indicate limited within-site heterogeneity and suggest that, under stratigraphically coherent conditions, increasing biological replication may provide little additional information, whereas enhancing technical replication and stratigraphic resolution can improve ecological inference from sedimentary DNA metabarcoding datasets.

DNA Barcoding, Taxonomic↗

The genome sequence of the common green lacewing, Chrysoperla carnea (Stephens, 1836).

We present a genome assembly from an individual female Chrysoperla carnea (a common green lacewing; Arthropoda; Insecta; Neuroptera; Chrysopidae). The genome sequence is 560 megabases in span. The majority of the assembly (95.70%) is scaffolded into six chromosomal pseudomolecules, with the X sex chromosome assembled. Gene annotation of this assembly by the NCBI Eukaryotic Genome Annotation Pipeline has identified 12,985 protein coding genes.

Chrysoperla carnea↗

The genome sequence of the plain-faced dronefly, Eristalis arbustorum (Linnaeus, 1758).

We present a genome assembly from an individual female Eristalis arbustorum (the plain-faced dronefly; Arthropoda; Insecta; Diptera; Syriphidae). The genome sequence is 451 megabases in span. The majority of the assembly (94.71%) is scaffolded into 6 chromosomal pseudomolecules, with the X sex chromosome assembled. The complete mitochondrial genome was also assembled and is 16.0 kilobases in length.

Diptera↗

The genome sequence of the bronze furrow bee, Seladonia tumulorum (Linnaeus, 1758).

We present the haploid genome assembly of an individual male Seladonia tumulorum (the bronze furrow bee; Arthropoda; Insecta; Hymenoptera; Halictidae). The genome sequence is 479 megabases in span. Most of the assembly (84.28%) is scaffolded into 17 chromosomal pseudomolecules. The mitochondrial genome was also assembled and is 17.3 kilobases in length. Gene annotation of this assembly on Ensembl identified 19,308 protein-coding genes. This assembly was generated as part of the Darwin Tree of Life project, which produces reference genomes for eukaryotic species found in Britain&#x202f;and&#x202f;Ireland.

Hymenoptera↗

The genome sequence of the Red-green Carpet, Chloroclysta siterata (Hufnagel, 1767).

We present a genome assembly from an individual male Chloroclysta siterata (the Red-green Carpet; Arthropoda; Insecta; Lepidoptera; Geometridae). The genome sequence is 437.9 megabases in span. Most of the assembly is scaffolded into 21 chromosomal pseudomolecules including the Z sex chromosome. The mitochondrial genome has also been assembled and is 16.7 kilobases in length. Gene annotation of this assembly on Ensembl identified 11,814 protein coding genes.

Chloroclysta siterata↗

The genome sequence of the Tufted Button, Acleris cristana (Denis & Schifferm&#xfc;ller, 1775).

We present a genome assembly from an individual female Acleris cristana (the Tufted Button; Arthropoda; Insecta; Lepidoptera; Tortricidae). The genome sequence is 562.6 megabases in span. Most of the assembly is scaffolded into 31 chromosomal pseudomolecules, including the W and Z sex chromosomes. The mitochondrial genome has also been assembled and is 16.1 kilobases in length. Gene annotation of this assembly on Ensembl identified 12,598 protein coding genes.

Acleris cristana↗

The genome sequence of the small wasp-sawfly, Tenthredo distinguenda (R. Stein, 1885).

We present a genome assembly from an individual male Tenthredo distinguenda (the small wasp-sawfly; Arthropoda; Insecta; Hymenoptera; Tenthredinidae). The genome sequence is 229.4 megabases in span. Most of the assembly is scaffolded into 9 chromosomal pseudomolecules. The mitochondrial genome has also been assembled and is 31.6 kilobases in length. Gene annotation of this assembly on Ensembl identified 11,332 protein coding genes.

Hymenoptera↗