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Huynh, T.-H.

Publications and source records attributed to Huynh, T.-H..

4 recordsLinked to original sources

Pond age and agricultural land cover influence the occurrence of Anopheles maculipennis in garden ponds in Hungary

Garden ponds are important elements of urban landscapes and provide numerous ecosystem services, but they may also support mosquito populations that can act as vectors of pathogens. However, mosquito occurrence in garden ponds has so far received limited attention. We engaged citizen scientists to provide data on their garden ponds and collect water samples for eDNA analysis to assess mosquito occurrence in 319 garden ponds across Hungary, with special focus on Anopheles maculipennis, a potential malaria-vector species. We tested the effects of land cover, local pond management activities and environmental factors on the probability of An. maculipennis occurrence in garden ponds. Overall mosquito occurrence was relatively low, with mosquitoes detected in 59 ponds (18%) and An. maculipennis detected in 46 ponds (14%). Agricultural land cover and pond age were associated with the occurrence of An. maculipennis in garden ponds. A higher percentage of agricultural land cover within 1000 m of garden ponds increased the probability of An. maculipennis occurrence, while occurrence was higher in newly created ponds ([≤] 2 years). Our results suggest that landscape context is more important than local pond characteristics in determining the occurrence of An. maculipennis in garden ponds. This study contributes to a better understanding of the landscape context in which a potential malaria-vector species occurs in urban and peri-urban environments and highlights the value of citizen science for large-scale data collection from privately owned ponds that are otherwise inaccessible to researchers.

ecology↗

Drivers of mosquito presence and abundance in urban and garden ponds in a European city

Mosquitoes in urban environments are considered unpleasant by citizens, and they can represent serious health risks as disease vectors. Invasive Aedes species are continuously spreading in Europe and have been increasingly reported from urban settlements. Some of these mosquito species have been associated with small artificial habitats. Therefore, their presence may also be expected in small plastic garden ponds, which are numerous in urban settings across many parts of Europe. Here, we aimed to determine whether urban waters host a high occurrence of mosquitoes and to identify the potential abiotic, biotic and landscape drivers of mosquito presence and abundance in urban ponds. We sampled 53 urban ponds in the city of Budapest (Hungary) of both natural and anthropogenic origin, and 40 garden ponds, which cover both highly urbanised areas and those with high green index in the suburbs. We collected data on macroinvertebrate communities, pond management, physico-chemical parameters, and pond characteristics (mainly morphology and vegetation cover) measured in situ. Two different mosquito detection techniques were used: dip-net sampling and eDNA. While only one invasive species (Aedes koreicus) was detected, occurring in a single pond, several other species were present, including potential malaria vectors increasingly reported from urban environments: the Anopheles maculipennis complex, An. claviger and An. plumbeus. Fish presence was negatively associated with both the presence and abundance of mosquitoes, regardless of pond type. Contrary to expectations, urbanisation did not play a major role in explaining mosquito presence or abundance. These results highlight the importance of local pond characteristics, and particularly the role of fish presence, in regulating mosquito populations in ponds in the urban landscape, although the broader ecological effects of fish on pond communities should also be considered.

ecology↗

Connectivity loss in experimental pond networks leads to biodiversity loss in microbial communities

Habitat fragmentation is among the most important global threats to biodiversity, however, the direct effects of its components including connectivity loss are still lesser known. Our understanding of these drivers is especially limited in microbial communities. Here, by conducting a four-month outdoor experiment with artificial pond (mesocosm) metacommunities, we studied the effects of connectivity loss on planktonic prokaryote and microeukaryote communities. Connectivity loss was simulated by stopping the dispersal among local habitats while keeping the habitat amount constant and the abiotic environment homogeneous. We found that connectivity loss led to higher levels of extinction and a decrease in both local and regional diversity in microeukaryotes. In contrast, diversity patterns of prokaryotes remained largely unaffected, with some indications of extinction debt. Connectivity loss also led to lower evenness in microeukaryotes, likely through changes in biotic interactions with zooplankton grazers. Our results imply that connectivity loss can directly translate into species losses in communities and highlight the importance of conserving habitat networks with sufficient dispersal among local habitats.

ecology↗

Metabolic dysregulation induces impaired lymphocyte memory formation during severe SARS-CoV-2 infection

Cellular metabolic dysregulation is a consequence of COVID-19 infection that is a key determinant of disease severity. To understand the mechanisms underlying these cellular changes, we performed high-dimensional immune cell profiling of PBMCs from COVID-19-infected patients, in combination with single cell transcriptomic analysis of COVID-19 BALFs. Hypoxia, a hallmark of COVID-19 ARDS, was found to elicit a global metabolic reprogramming in effector lymphocytes. In response to oxygen and nutrient-deprived microenvironments, these cells shift from aerobic respiration to increase their dependence on anaerobic processes including glycolysis, mitophagy, and glutaminolysis to fulfill their bioenergetic demands. We also demonstrate metabolic dysregulation of ciliated lung epithelial cells is linked to significant increase of proinflammatory cytokine secretion and upregulation of HLA class 1 machinery. Augmented HLA class-1 antigen stimulation by epithelial cells leads to cellular exhaustion of metabolically dysregulated CD8 and NK cells, impairing their memory cell differentiation. Unsupervised clustering techniques revealed multiple distinct, differentially abundant CD8 and NK memory cell states that are marked by high glycolytic flux, mitochondrial dysfunction, and cellular exhaustion, further highlighting the connection between disrupted metabolism and impaired memory cell function in COVID-19. Our findings provide novel insight on how SARS-CoV-2 infection affects host immunometabolism and anti-viral response during COVID-19. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=85 SRC="FIGDIR/small/471421v1_ufig1.gif" ALT="Figure 1"> View larger version (32K): org.highwire.dtl.DTLVardef@18bff7borg.highwire.dtl.DTLVardef@31f46borg.highwire.dtl.DTLVardef@1a5ad50org.highwire.dtl.DTLVardef@1577a0_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIHypoxia and anaerobic glycolysis drive CD8, NK, NKT dysfunction C_LIO_LIHypoxia and anaerobic glycolysis impair memory differentiation in CD8 and NK cells C_LIO_LIHypoxia and anaerobic glycolysis cause mitochondrial dysfunction in CD8, NK, NKT cells C_LI

immunology↗