26 research outputs found

    Mobilizing the (Im)Mobile Museum Through Hybrid Curation: A Story of Hybrid Curation of Cultural Practice During the COVID-19 Pandemic

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    This narrative research report summarizes the experiences of Vivid Ethnicity, a mobile anthropological museum of the Museum of Cultural Anthropology at Mahidol University, Thailand, during the lockdowns caused by the COVID-19 pandemic in 2020-2022. Although Vivid Ethnicity was rendered immobile and forced to stop travelling during the pandemic, it developed a hybrid curatorial method to stay connected and engaged with its audiences and research partners in two ethnic villages in Chiang Mai province. A key lesson of this experience is that hands-on information and communication technologies can help maintain a certain proximity with the audiences and research partners in times of physical absence. We also learned that an empathetic mindset on the part of everyone involved in the project, along with a human-centric design, are crucial components of what we call the hybrid curation of cultural practice

    Functional redundancy of Burkholderia pseudomallei phospholipase C enzymes and their role in virulence

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    This is the final version. Available on open access from Nature Research via the DOI in this recordPhospholipase C (PLC) enzymes are key virulence factors in several pathogenic bacteria. Burkholderia pseudomallei, the causative agent of melioidosis, possesses at least three plc genes (plc1, plc2 and plc3). We found that in culture medium plc1 gene expression increased with increasing pH, whilst expression of the plc3 gene was pH (4.5 to 9.0) independent. Expression of the plc2 gene was not detected in culture medium. All three plc genes were expressed during macrophage infection by B. pseudomallei K96243. Comparing B. pseudomallei wild-type with plc mutants revealed that plc2, plc12 or plc123 mutants showed reduced intracellular survival in macrophages and reduced plaque formation in HeLa cells. However, plc1 or plc3 mutants showed no significant differences in plaque formation compared to wild-type bacteria. These findings suggest that Plc2, but not Plc1 or Plc3 are required for infection of host cells. In Galleria mellonella, plc1, plc2 or plc3 mutants were not attenuated compared to the wild-type strain, but multiple plc mutants showed reduced virulence. These findings indicate functional redundancy of the B. pseudomallei phospholipases in virulence.Mahidol UniversityThailand Research Fun

    Analysis of the role of the QseBC two-component sensory system in epinephrine-induced motility and intracellular replication of Burkholderia pseudomallei

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    Burkholderia pseudomallei is a facultative intracellular bacterial pathogen that causes melioidosis, a severe invasive disease of humans. We previously reported that the stress-related catecholamine hormone epinephrine enhances motility of B. pseudomallei, transcription of flagellar genes and the production of flagellin. It has been reported that the QseBC two-component sensory system regulates motility and virulence-associated genes in other Gram-negative bacteria in response to stress-related catecholamines, albeit disparities between studies exist. We constructed and whole-genome sequenced a mutant of B. pseudomallei with a deletion spanning the predicted qseBC homologues (bpsl0806 and bpsl0807). The ΔqseBC mutant exhibited significantly reduced swimming and swarming motility and reduced transcription of fliC. It also exhibited a defect in biofilm formation and net intracellular survival in J774A.1 murine macrophage-like cells. While epinephrine enhanced bacterial motility and fliC transcription, no further reduction in these phenotypes was observed with the ΔqseBC mutant in the presence of epinephrine. Plasmid-mediated expression of qseBC suppressed bacterial growth, complicating attempts to trans-complement mutant phenotypes. Our data support a role for QseBC in motility, biofilm formation and net intracellular survival of B. pseudomallei, but indicate that it is not essential for epinephrine-induced motility per se

    Detection and differentiation of Burkholderia species with pathogenic potential in environmental soil samples

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    The Burkholderia pseudomallei phylogenetic cluster includes B. pseudomallei, B. mallei, B. thailandensis, B. oklahomensis, B. humptydooensis and B. singularis. Regarded as the only pathogenic members of this group, B. pseudomallei and B. mallei cause the diseases melioidosis and glanders, respectively. Additionally, variant strains of B. pseudomallei and B. thailandensis exist that include the geographically restricted B. pseudomallei that express a B. mallei-like BimA protein (BPBM), and B. thailandensis that express a B. pseudomallei-like capsular polysaccharide (BTCV). To establish a PCR-based assay for the detection of pathogenic Burkholderia species or their variants, five PCR primers were designed to amplify species-specific sequences within the bimA (Burkholderia intracellular motility A) gene. Our multiplex PCR assay could distinguish pathogenic B. pseudomallei and BPBM from the non-pathogenic B. thailandensis and the BTCV strains. A second singleplex PCR successfully discriminated the BTCV from B. thailandensis. Apart from B. humptydooensis, specificity testing against other Burkholderia spp., as well as other Gram-negative and Gram-positive bacteria produced a negative result. The detection limit of the multiplex PCR in soil samples artificially spiked with known quantities of B. pseudomallei and B. thailandensis were 5 and 6 CFU/g soil, respectively. Furthermore, comparison between standard bacterial culture and the multiplex PCR to detect B. pseudomallei from 34 soil samples, collected from an endemic area of melioidosis, showed high sensitivity and specificity. This robust, sensitive, and specific PCR assay will be a useful tool for epidemiological study of B. pseudomallei and closely related members with pathogenic potential in soil

    Identification of Burkholderia pseudomallei Genes Induced During Infection of Macrophages by Differential Fluorescence Induction

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    This is the final version. Available on open access from Frontiers media via the DOI in this recordData Availability Statement: The datasets GENERATED for this study can be found in the SNBI SRA accession PRJNA599542.Burkholderia pseudomallei, the causative agent of melioidosis, can survive and replicate in macrophages. Little is known about B. pseudomallei genes that are induced during macrophage infection. We constructed a B. pseudomallei K96243 promoter trap library with genomic DNA fragments fused to the 5′ end of a plasmid-borne gene encoding enhanced green fluorescent protein (eGFP). Microarray analysis showed that the library spanned 88% of the B. pseudomallei genome. The recombinant plasmids were introduced into Burkholderia thailandensis E264, and promoter fusions active during in vitro culture were removed. J774A.1 murine macrophages were infected with the promoter trap library, and J774A.1 cells containing fluorescent bacteria carrying plasmids with active promoters were isolated using flow cytometric-based cell sorting. Candidate macrophage-induced B. pseudomallei genes were identified from the location of the insertions containing an active promoter activity. A proportion of the 138 genes identified in this way have been previously reported to be involved in metabolism and transport, virulence, or adaptation. Novel macrophage-induced B. pseudomallei genes were also identified. Quantitative reverse-transcription PCR analysis of 13 selected genes confirmed gene induction during macrophage infection. Deletion mutants of two macrophage-induced genes from this study were attenuated in Galleria mellonella larvae, suggesting roles in virulence. B. pseudomallei genes activated during macrophage infection may contribute to intracellular life and pathogenesis and merit further investigation toward control strategies for melioidosis.Mahidol University, ThailandThailand Research Fun

    Induced Burkholderia prophages detected from the hemoculture: a biomarker for Burkholderia pseudomallei infection.

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    Bacteriophages (phages), viruses that infect bacteria, are found in abundance not only in the environment but also in the human body. The use of phages for the diagnosis of melioidosis, a tropical infectious disease caused by Burkholderia pseudomallei, is emerging as a promising novel approach, but our understanding of conditions under which Burkholderia prophages can be induced remains limited. Here, we first demonstrated the isolation of Burkholderia phages from the hemocultures of melioidosis patients. The B. pseudomallei-positive hemoculture bottles were filtered to remove bacteria, and then phages were isolated and purified by spot and double agar overlay plaque assays. Forty blood samples (hemoculture-confirmed melioidosis) were tested, and phages were found in 30% of the samples. Transmission electron microscopy and genome analysis of the isolated phages, vB_HM387 and vB_HM795, showed that both phages are Myoviruses. These two phages were stable at a pH of 5-7 and temperatures of 25-37°C, suggesting their ability to survive in human blood. The genome sizes of vB_HM387 and vB_HM795 are 36.3 and 44.0 kb, respectively. A phylogenetic analysis indicated that vB_HM387 has homologs, but vB_HM795 is a novel Myovirus, suggesting the heterogeneity of Burkholderia phages in melioidosis patients. The key finding that Burkholderia phages could be isolated from the blood of melioidosis patients highlights the potential application of phage-based assays by detecting phages in blood as a pathogen-derived biomarker of infection

    The Role of the County Professional Council in Advanced Training and Professional Development of Class Teachers

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    Stručno usvršavanje je obvezan dio učiteljskog posla koji se provodi na četiri osnovne razine: individualnoj, školskoj, županijskoj i državnoj. Brojne su prednosti i nedostaci svakog oblika usavršavanja, a svi su oni na putu profesionalnog razvoja učitelja jednako važni i korisni. U radu je prikazan model stručnog usvršavanja učitelja na županijskoj razini (Županijsko stručno vijeće učitelja razredne nastave – Grad Sisak) pri čemu veliku ulogu imaju upravo županijski voditelji koji su poveznica između školske i državne razine stručnog usavršavanja učitelja.Advanced training is a mandatory part of teacher’s job and it is being carried out at four basic levels: individual, school, county and state level. There are numerous advantages and disadvantages of any form of training, and they are all equally important and useful in the course of professional development of teachers. This study presents the model of advanced training of class teachers at county level (County professional council of class teachers – the Town of Sisak), where the very county leaders, who are the link between the school and state level of advanced training of teachers, have a great role

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

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    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century
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