Household Air Pollution Interventions to Improve Health in Low- and Middle-Income Countries: An Official American Thoracic Society Research Statement.

Background: An estimated 3 billion people, largely in low- and middle-income countries, rely on unclean fuels for cooking, heating, and lighting to meet household energy needs. The resulting exposure to household air pollution (HAP) is a leading cause of pneumonia, chronic lung disease, and other adverse health effects. In the last decade, randomized controlled trials of clean cooking interventions to reduce HAP have been conducted. We aim to provide guidance on how to interpret the findings of these trials and how they should inform policy makers and practitioners.Methods: We assembled a multidisciplinary working group of international researchers, public health practitioners, and policymakers with expertise in household air pollution from within academia, the American Thoracic Society, funders, nongovernmental organizations, and global organizations, including the World Bank and the World Health Organization. We performed a literature search, convened four sessions via web conference, and developed consensus conclusions and recommendations via the Delphi method.Results: The committee reached consensus on 14 conclusions and recommendations. Although some trials using cleaner-burning biomass stoves or cleaner-cooking fuels have reduced HAP exposure, the committee was divided (with 55% saying no and 45% saying yes) on whether the studied interventions improved measured health outcomes.Conclusions: HAP is associated with adverse health effects in observational studies. However, it remains unclear which household energy interventions reduce exposure, improve health, can be scaled, and are sustainable. Researchers should engage with policy makers and practitioners working to scale cleaner energy solutions to understand and address their information needs.

Intense P.1 (Gamma) diversification followed by rapid Delta substitution in Southern Brazil: a SARS-CoV-2 genomic epidemiology study.

The analyses of genetic traits, dispersion patterns and phylogenomics are essential for understanding the evolutionary forces driving SARS-CoV-2 viruses in these three years of COVID-19 pandemics. Brazil is one of the most affected countries in the world and not sufficient genomic studies have been performed. The emergence of P.1 lineage led to one of the most serious public health crises on record. Our study presents the genomic sequencing and characterization of 412 samples from Rio Grande do Sul state, in the Brazilian Southern region, during Gamma and Delta epidemic waves, in 2021. Additionally, molecular evolution tests were performed to identify positively selected sites in Brazil between 2020 and 2022, as well as offer some evolutionary perspective about the maintenance of multiple spike mutations in Omicron lineages. Genomic epidemiology analysis has indicated an intense P.1 (Gamma) diversification followed by rapid Delta substitution in Southern Brazil.

Genomic characterization and molecular evolution of human monkeypox viruses.

Monkeypox virus is a member of the family Poxviridae, as are variola virus and vaccinia virus. It has a linear double-strand DNA genome approximately 197 kb long, containing ~190 non-overlapping ORFs. Comparison of members of the Central and West African clades shows the presence of unique genes that are associated with different disease presentations, depending on the strain. The last smallpox vaccination efforts ended in the mid-1980s, and there is concern about the recent spread of human monkeypox disease around the world. Almost 87,000 human monkeypox cases have been diagnosed in the world, of which more than 10,900 were in Brazil. The aim of this study was to evaluate the epidemiology and molecular evolution of hMpxV. From computational biology analysis of 640 hMpxV genomes from 1962 to 2022, synteny breaks and gene conservation were observed between Central and West clade genomes, and strains belonged with the 2022 outbreak assigned to the West African clade. Evidence was found for diversifying selective pressure at specific sites within protein coding sequences, acting on immunomodulatory processes. The existence of different sites under diversifying and purifying selection in paralog genes indicates adaptive mechanisms underlying the host-pathogen interaction of monkeypox virus in humans.

The MetaGens algorithm for metagenomic database lossy compression and subject alignment.

The advancement of genetic sequencing techniques led to the production of a large volume of data. The extraction of genetic material from a sample is one of the early steps of the metagenomic study. With the evolution of the processes, the analysis of the sequenced data allowed the discovery of etiological agents and, by corollary, the diagnosis of infections. One of the biggest challenges of the technique is the huge volume of data generated with each new technology developed. To introduce an algorithm that may reduce the data volume, allowing faster DNA matching with the reference databases. Using techniques like lossy compression and substitution matrix, it is possible to match nucleotide sequences without losing the subject. This lossy compression explores the nature of DNA mutations, insertions and deletions and the possibility that different sequences are the same subject. The algorithm can reduce the overall size of the database to 15% of the original size. Depending on parameters, it may reduce up to 5% of the original size. Although is the same as the other platforms, the match algorithm is more sensible because it ignores the transitions and transversions, resulting in a faster way to obtain the diagnostic results. The first experiment results in an increase in speed 10 times faster than Blast while maintaining high sensitivity. This performance gain can be extended by combining other techniques already used in other studies, such as hash tables. Database URL https://github.com/ghc4/metagens.

Genomic characterization and molecular evolution of SARS-CoV-2 in Rio Grande do Sul State, Brazil.

SARS-CoV-2 is the virus responsible for the COVID-19 and has afflicted the world since the end of 2019. Different lineages have been discovered and the Gamma lineage, which started the second wave of infections, was first described in Brazil, one of the most affected countries by pandemic. Therefore, this study analyzed SARS-CoV-2 sequenced genomes from Esteio city in Rio Grande do Sul, Southern Brazil. We also comparatively analyzed genomes of the two first years of the pandemic from Rio Grande do Sul state for understanding their genomic and evolutionary patterns. The phylogenomic analysis showed monophyletic groups for Alpha, Gamma, Delta and Omicron, as well as for other circulating lineages in the state. Molecular evolutionary analysis identified several sites under adaptive selection in membrane and nucleocapsid proteins which could be related to a prevalent stabilizing effect on membrane protein structure, as well as majoritarily destabilizing effects on C-terminal nucleocapsid domain.

Molecular evolution and structural analyses of the spike glycoprotein from Brazilian SARS-CoV-2 genomes: the impact of selected mutations.

The COVID-19 pandemic caused by SARS-CoV-2 has reached by February 2022 more than 380 million cases and 5.5 million deaths worldwide since its beginning in late 2019, leading to enhanced concern in the scientific community and the general population. One of the most important pieces of this host-pathogen interaction is the spike protein, which binds to the hACE2 cell receptor, mediates the membrane fusion and is the major target of neutralizing antibodies against SARS-CoV-2. The multiple amino acid substitutions observed in this region, specially in RBD have enhanced the hACE2 binding affinity and led to several modifications in the mechanisms of SARS-CoV-2 pathogenesis, improving the viral fitness and/or promoting immune evasion, with potential impact in the vaccine development. In this work, we identified 48 sites under selective pressures, 17 of them with the strongest evidence by the HyPhy tests, including VOC related mutation sites 138, 142, 222, 262, 484, 681, and 845, among others. The coevolutionary analysis identified 28 sites found not to be conditionally independent, such as E484K-N501Y. The molecular dynamics and free energy estimates showed the structural stabilizing effect and the higher impact of E484K for enhanced binding affinity between the spike RBD and hACE2 in P.1 and P.2 lineages (specially with L452V). Structural changes were also identified in the hACE molecule when interacting with B.1.1.7 RDB. Despite some destabilizing substitutions, a stabilizing effect was identified for the majority of the positively selected mutations.Communicated by Ramaswamy H. Sarma.

Molecular evolution and structural analyses of proteins involved in metabolic pathways of volatile organic compounds in Petunia hybrida (Solanaceae).

The association between plants and their pollinators is essential for increasing the diversity in angiosperms. Morphological and physiological traits, mainly floral scent, can influence the pollination dynamics and select pollinators for each plant species. In this work, we studied two proteins involved in producing volatile organic compounds in plants, conyferyl alcohol acyltransferase (CFAT) and benzoyl-CoA:benzyl alcohol/phenyl ethanol benzoyl transferase (BPBT) genes. We aimed to understand these proteins with respect to evolutionary and structural aspects and functions in Solanaceae using phylogenetic methods and comparative molecular modeling. We used Bayesian inference to describe the proteins' evolutionary history using Petunia x hybrida as a query to search for homologs in the Solanaceae family. Theoretical 3D models were obtained for both proteins using Panicum virgatum as a template. The phylogenetic tree included several different enzymes with diverse biological roles in Solanaceae, displaying the transferase domain. We identified only one sequence of CFAT in the databases, which belongs to Petunia x hybrida, and found several BPBT sequences from the genera Nicotiana, Solanum, and Capsicum. The 3D structures of CFAT and BPBT have two different domains, and we have identified the amino acid residues essential for the enzymatic activity and interaction with substrates.

Evolutionary and structural aspects of Solanaceae RNases T2.

Plant RNases T2 are involved in several physiological and developmental processes, including inorganic phosphate starvation, senescence, wounding, defense against pathogens, and the self-incompatibility system. Solanaceae RNases form three main clades, one composed exclusively of S-RNases and two that include S-like RNases. We identified several positively selected amino acids located in highly flexible regions of these molecules, mainly close to the B1 and B2 substrate-binding sites in S-like RNases and the hypervariable regions of S-RNases. These differences between S- and S-like RNases in the flexibility of amino acids in substrate-binding regions are essential to understand the RNA-binding process. For example, in the S-like RNase NT, two positively selected amino acid residues (Tyr156 and Asn134) are located at the most flexible sites on the molecular surface. RNase NT is induced in response to tobacco mosaic virus infection; these sites may thus be regions of interaction with pathogen proteins or viral RNA. Differential selective pressures acting on plant ribonucleases have increased amino acid variability and, consequently, structural differences within and among S-like RNases and S-RNases that seem to be essential for these proteins play different functions.

Acute kidney injury associated with rhabdomyolysis in a patient with COVID-19 / Lesão renal aguda associada à rabdomiólise em um paciente com COVID-19

Abstract Rhabdomyolysis is defined as the breakdown of skeletal muscle leading to the release of muscle contents into the extracellular fluid. Patients with rhabdomyolysis can be asymptomatic or have myalgia symptoms, weakness, myoglobinuria with dark urine, significant electrolyte imbalance, and acute kidney injury. Here we describe a case on acute kidney injury associated to rhabdomyolysis in a patient with COVID-19.

Resumo A rabdomiólise é definida como a lise da musculatura esquelética levando à liberação do conteúdo muscular para o fluido extracelular. Pacientes com rabdomiólise podem ser assintomáticos ou apresentar sintomas de mialgia, fraqueza, mioglobinúria com urina escura, desequilíbrio eletrolítico significativo e lesão renal aguda. Aqui descrevemos um caso de lesão renal aguda associada à rabdomiólise em um paciente com COVID-19.

Systemic redox imbalance in severe COVID-19 patients.

The aim of this study was to evaluate the systemic redox state and inflammatory markers in intensive care unit (ICU) or non-ICU severe COVID-19 patients during the hospitalization period. Blood samples were collected at hospital admission (T1) (Controls and COVID-19 patients), 5-7 days after admission (T2: 5-7 days after hospital admission), and at the discharge time from the hospital (T3: 0-72 h before leaving hospital or death) to analyze systemic oxidative stress markers and inflammatory variables. The reactive oxygen species (ROS) production and mitochondrial membrane potential (MMP) were analyzed in peripheral granulocytes and monocytes. THP-1 human monocytic cell line was incubated with plasma from non-ICU and ICU COVID-19 patients and cell viability and apoptosis rate were analyzed. Higher total antioxidant capacity, protein oxidation, lipid peroxidation, and IL-6 at hospital admission were identified in both non-ICU and ICU COVID-19 patients. ICU COVID-19 patients presented increased C-reactive protein, ROS levels, and protein oxidation over hospitalization period compared to non-ICU patients, despite increased antioxidant status. Granulocytes and monocytes of non-ICU and ICU COVID-19 patients presented lower MMP and higher ROS production compared to the healthy controls, with the highest values found in ICU COVID-19 group. Finally, the incubation of THP-1 cells with plasma acquired from ICU COVID-19 patients at T3 hospitalization period decreased cell viability and apoptosis rate. In conclusion, disturbance in redox state is a hallmark of severe COVID-19 and is associated with cell damage and death.

Comparative Genomics and Characterization of SARS-CoV-2 P.1 (Gamma) Variant of Concern From Amazonas, Brazil.

BACKGROUND: P.1 lineage (Gamma) was first described in the State of Amazonas, northern Brazil, in the end of 2020, and has emerged as a very important variant of concern (VOC) of SARS-CoV-2 worldwide. P.1 has been linked to increased infectivity, higher mortality, and immune evasion, leading to reinfections and potentially reduced efficacy of vaccines and neutralizing antibodies. METHODS: The samples of 276 patients from the State of Amazonas were sent to a central referral laboratory for sequencing by gold standard techniques, through Illumina MiSeq platform. Both global and regional phylogenetic analyses of the successfully sequenced genomes were conducted through maximum likelihood method. Multiple alignments were obtained including previously obtained unique human SARS-CoV-2 sequences. The evolutionary histories of spike and non-structural proteins from ORF1a of northern genomes were described and their molecular evolution was analyzed for detection of positive (FUBAR, FEL, and MEME) and negative (FEL and SLAC) selective pressures. To further evaluate the possible pathways of evolution leading to the emergence of P.1, we performed specific analysis for copy-choice recombination events. A global phylogenomic analysis with subsampled P.1 and B.1.1.28 genomes was applied to evaluate the relationship among samples. RESULTS: Forty-four samples from the State of Amazonas were successfully sequenced and confirmed as P.1 (Gamma) lineage. In addition to previously described P.1 characteristic mutations, we find evidence of continuous diversification of SARS-CoV-2, as rare and previously unseen P.1 mutations were detected in spike and non-structural protein from ORF1a. No evidence of recombination was found. Several sites were demonstrated to be under positive and negative selection, with various mutations identified mostly in P.1 lineage. According to the Pango assignment, phylogenomic analyses indicate all samples as belonging to the P.1 lineage. CONCLUSION: P.1 has shown continuous evolution after its emergence. The lack of clear evidence for recombination and the positive selection demonstrated for several sites suggest that this lineage emergence resulted mainly from strong evolutionary forces and progressive accumulation of a favorable signature set of mutations.

Acute kidney injury associated with rhabdomyolysis in a patient with COVID-19.

Rhabdomyolysis is defined as the breakdown of skeletal muscle leading to the release of muscle contents into the extracellular fluid. Patients with rhabdomyolysis can be asymptomatic or have myalgia symptoms, weakness, myoglobinuria with dark urine, significant electrolyte imbalance, and acute kidney injury. Here we describe a case on acute kidney injury associated to rhabdomyolysis in a patient with COVID-19.

Increased LPS levels coexist with systemic inflammation and result in monocyte activation in severe COVID-19 patients.

Mucosal barrier alterations may play a role in the pathogenesis of several diseases, including COVID-19. In this study we evaluate the association between bacterial translocation markers and systemic inflammation at the earliest time-point after hospitalization and at the last 72 h of hospitalization in survivors and non-survivors COVID-19 patients. Sixty-six SARS-CoV-2 RT-PCR positive patients and nine non-COVID-19 pneumonia controls were admitted in this study. Blood samples were collected at hospital admission (T1) (Controls and COVID-19 patients) and 0-72 h before hospital discharge (T2, alive or dead) to analyze systemic cytokines and chemokines, lipopolysaccharide (LPS) concentrations and soluble CD14 (sCD14) levels. THP-1 human monocytic cell line was incubated with plasma from survivors and non-survivors COVID-19 patients and their phenotype, activation status, TLR4, and chemokine receptors were analyzed by flow cytometry. COVID-19 patients presented higher IL-6, IFN-γ, TNF-α, TGF-ß1, CCL2/MCP-1, CCL4/MIP-1ß, and CCL5/RANTES levels than controls. Moreover, LPS and sCD14 were higher at hospital admission in SARS-CoV-2-infected patients. Non-survivors COVID-19 patients had increased LPS levels concomitant with higher IL-6, TNF-α, CCL2/MCP-1, and CCL5/RANTES levels at T2. Increased expression of CD16 and CCR5 were identified in THP-1 cells incubated with the plasma of survivor patients obtained at T2. The incubation of THP-1 with T2 plasma of non-survivors COVID-19 leads to higher TLR4, CCR2, CCR5, CCR7, and CD69 expression. In conclusion, the coexistence of increased microbial translocation and hyperinflammation in patients with severe COVID-19 may lead to higher monocyte activation, which may be associated with worsening outcomes, such as death.

Predominance of the SARS-CoV-2 Lineage P.1 and Its Sublineage P.1.2 in Patients from the Metropolitan Region of Porto Alegre, Southern Brazil in March 2021.

Almost a year after the COVID-19 pandemic had begun, new lineages (B.1.1.7, B.1.351, P.1, and B.1.617.2) associated with enhanced transmissibility, immunity evasion, and mortality were identified in the United Kingdom, South Africa, and Brazil. The previous most prevalent lineages in the state of Rio Grande do Sul (RS, Southern Brazil), B.1.1.28 and B.1.1.33, were rapidly replaced by P.1 and P.2, two B.1.1.28-derived lineages harboring the E484K mutation. To perform a genomic characterization from the metropolitan region of Porto Alegre, we sequenced viral samples to: (i) identify the prevalence of SARS-CoV-2 lineages in the region, the state, and bordering countries/regions; (ii) characterize the mutation spectra; (iii) hypothesize viral dispersal routes by using phylogenetic and phylogeographic approaches. We found that 96.4% of the samples belonged to the P.1 lineage and approximately 20% of them were assigned as the novel P.1.2, a P.1-derived sublineage harboring signature substitutions recently described in other Brazilian states and foreign countries. Moreover, sequences from this study were allocated in distinct branches of the P.1 phylogeny, suggesting multiple introductions in RS and placing this state as a potential diffusion core of P.1-derived clades and the emergence of P.1.2. It is uncertain whether the emergence of P.1.2 and other P.1 clades is related to clinical or epidemiological consequences. However, the clear signs of molecular diversity from the recently introduced P.1 warrant further genomic surveillance.

Mutation hotspots and spatiotemporal distribution of SARS-CoV-2 lineages in Brazil, February 2020-2021.

The COVID-19 pandemic has already reached more than 110 million people and is associated with 2.5 million deaths worldwide. Brazil is the third worst-hit country, with approximately 10.2 million cases and 250 thousand deaths. International efforts have been established to share information about Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemiology and evolution to support the development of effective strategies for public health and disease management. We aimed to analyze the high-quality genome sequences from Brazil from February 2020-2021 to identify mutation hotspots, geographical and temporal distribution of SARS-CoV-2 lineages by using phylogenetics and phylodynamics analyses. We describe heterogeneous sequencing efforts, the progression of the different lineages along time, evaluating mutational spectra and frequency oscillations derived from the prevalence of specific lineages across different Brazilian regions. We found at least seven major (1-7) and two minor clades related to the six most prevalent lineages in the country and described its spatial distribution and dynamics. The emergence and recent frequency shift of lineages (P.1 and P.2) carrying mutations of concern in the spike protein (e. g., E484K, N501Y) draws attention due to their association with immune evasion and enhanced receptor binding affinity. Improvements in genomic surveillance are of paramount importance and should be extended in Brazil to better inform policy makers about better decisions to fight the COVID-19 pandemic.

Population-based prevalence surveys during the Covid-19 pandemic: A systematic review.

Population-based prevalence surveys of Covid-19 contribute to establish the burden of infection, the role of asymptomatic and mild infections in transmission, and allow more precise decisions about reopen policies. We performed a systematic review to evaluate qualitative aspects of these studies, assessing their reliability and compiling practices that can influence the methodological quality. We searched MEDLINE, EMBASE, bioRxiv and medRxiv, and included cross-sectional studies using molecular and/or serological tests to estimate the prevalence of Covid-19 in the general population. Survey quality was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Prevalence Studies. A correspondence analysis correlated methodological parameters of each study to identify patterns related to higher, intermediate and lower risks of bias. The available data described 37 surveys from 19 countries. The majority were from Europe and America, used antibody testing, and reached highly heterogeneous sample sizes and prevalence estimates. Minority communities were disproportionately affected by Covid-19. Important risk of bias was detected in four domains: sample size, data analysis with sufficient coverage, measurements in standard way and response rate. The correspondence analysis showed few consistent patterns for high risk of bias. Intermediate risk of bias was related to American and European studies, municipal and regional initiatives, blood samples and prevalence >1%. Low risk of bias was related to Asian studies, nationwide initiatives, reverse-transcriptase polymerase chain reaction tests and prevalence <1%. We identified methodological standards applied worldwide in Covid-19 prevalence surveys, which may assist researchers with the planning, execution and reporting of future population-based surveys.

E484K as an innovative phylogenetic event for viral evolution: Genomic analysis of the E484K spike mutation in SARS-CoV-2 lineages from Brazil.

The COVID-19 pandemic caused by SARS-CoV-2 has affected millions of people since its beginning in 2019. The propagation of new lineages and the discovery of key mechanisms adopted by the virus to overlap the immune system are central topics for the entire public health policies, research and disease management. Since the second semester of 2020, the mutation E484K has been progressively found in the Brazilian territory, composing different lineages over time. It brought multiple concerns related to the risk of reinfection and the effectiveness of new preventive and treatment strategies due to the possibility of escaping from neutralizing antibodies. To better characterize the current scenario we performed genomic and phylogenetic analyses of the E484K mutated genomes sequenced from Brazilian samples in 2020. From October 2020, more than 40% of the sequenced genomes present the E484K mutation, which was identified in three different lineages (P.1, P.2 and B.1.1.33 - posteriorly renamed as N.9) in four Brazilian regions. We also evaluated the presence of E484K associated mutations and identified selective pressures acting on the spike protein, leading us to some insights about adaptive and purifying selection driving the virus evolution.

Genomic epidemiology of SARS-CoV-2 in Esteio, Rio Grande do Sul, Brazil.

BACKGROUND: Brazil is the third country most affected by Coronavirus disease-2019 (COVID-19), but viral evolution in municipality resolution is still poorly understood in Brazil and it is crucial to understand the epidemiology of viral spread. We aimed to track molecular evolution and spread of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Esteio (Southern Brazil) using phylogenetics and phylodynamics inferences from 21 new genomes in global and regional context. Importantly, the case fatality rate (CFR) in Esteio (3.26%) is slightly higher compared to the Rio Grande do Sul (RS) state (2.56%) and the entire Brazil (2.74%). RESULTS: We provided a comprehensive view of mutations from a representative sampling from May to October 2020, highlighting two frequent mutations in spike glycoprotein (D614G and V1176F), an emergent mutation (E484K) in spike Receptor Binding Domain (RBD) characteristic of the B.1.351 and P.1 lineages, and the adjacent replacement of 2 amino acids in Nucleocapsid phosphoprotein (R203K and G204R). E484K was found in two genomes from mid-October, which is the earliest description of this mutation in Southern Brazil. Lineages containing this substitution must be subject of intense surveillance due to its association with immune evasion. We also found two epidemiologically-related clusters, including one from patients of the same neighborhood. Phylogenetics and phylodynamics analysis demonstrates multiple introductions of the Brazilian most prevalent lineages (B.1.1.33 and B.1.1.248) and the establishment of Brazilian lineages ignited from the Southeast to other Brazilian regions. CONCLUSIONS: Our data show the value of correlating clinical, epidemiological and genomic information for the understanding of viral evolution and its spatial distribution over time. This is of paramount importance to better inform policy making strategies to fight COVID-19.

Computational studies of polyurethanases from Pseudomonas.

Polyurethanes (PU) are multifunctional polymers, used in automotive industry, in coatings, rigid and flexible foams, and also in biomimetic materials. In the same way as all plastic waste, the incorrect disposal of these materials leads to the accumulation of polyurethanes in the environment. To reduce the amount of waste as well as add value to degradation products, bioremediation methods have been studied for waste management of PU. Enzymes of the hydrolases class have been experimentally tested for enzymatic degradation of PU, with very promising results. In this work, two enzymes that can degrade polyurethanes were studied by molecular dynamics simulations: a protease and an esterase, both from Pseudomonas. From molecular dynamics simulations analysis, it was observed the stability of the structures, both in the simulations of the free enzymes and in the simulations of the complexes with a PU monomer. Hydrogen bonds were formed with the monomer and the enzymes throughout the simulation time, and the interaction free energy was found to be strongly negative, pointing to strong interactions in both cases.

Cestode strobilation: prediction of developmental genes and pathways.

BACKGROUND: Cestoda is a class of endoparasitic worms in the flatworm phylum (Platyhelminthes). During the course of their evolution cestodes have evolved some interesting aspects, such as their increased reproductive capacity. In this sense, they have serial repetition of their reproductive organs in the adult stage, which is often associated with external segmentation in a developmental process called strobilation. However, the molecular basis of strobilation is poorly understood. To assess this issue, an evolutionary comparative study among strobilated and non-strobilated flatworm species was conducted to identify genes and proteins related to the strobilation process. RESULTS: We compared the genomic content of 10 parasitic platyhelminth species; five from cestode species, representing strobilated parasitic platyhelminths, and five from trematode species, representing non-strobilated parasitic platyhelminths. This dataset was used to identify 1813 genes with orthologues that are present in all cestode (strobilated) species, but absent from at least one trematode (non-strobilated) species. Development-related genes, along with genes of unknown function (UF), were then selected based on their transcriptional profiles, resulting in a total of 34 genes that were differentially expressed between the larval (pre-strobilation) and adult (strobilated) stages in at least one cestode species. These 34 genes were then assumed to be strobilation related; they included 12 encoding proteins of known function, with 6 related to the Wnt, TGF-ß/BMP, or G-protein coupled receptor signaling pathways; and 22 encoding UF proteins. In order to assign function to at least some of the UF genes/proteins, a global gene co-expression analysis was performed for the cestode species Echinococcus multilocularis. This resulted in eight UF genes/proteins being predicted as related to developmental, reproductive, vesicle transport, or signaling processes. CONCLUSIONS: Overall, the described in silico data provided evidence of the involvement of 34 genes/proteins and at least 3 developmental pathways in the cestode strobilation process. These results highlight on the molecular mechanisms and evolution of the cestode strobilation process, and point to several interesting proteins as potential developmental markers and/or targets for the development of novel antihelminthic drugs.