Pathogenic Conditions Research Articles

Characteristics of plastic bronchitis in children with infectious pneumonia

BackgroundMultiple studies have reported that infectious pneumonia can induce the production of plastic casts, which threatens children's health. We explored the characteristics of plastic bronchitis (PB) in clinical practice by analysing clinical medical records.MethodsA retrospective study was conducted. Children with pneumonia and large chest shadows were included in this study. The differences in characteristics between patients with plastic bronchitis and those without plastic bronchitis were analysed. The distribution of pathogens was statistically analysed. Grouping analysis based on PB and pathogen conditions was also conducted.ResultsA total of 185 patients were included in this study. The patients were divided into two groups: the PB group (n = 48) and the non-PB group (n = 137). The duration of illness before hospitalization in the PB group was mostly longer than that in the non-PB group. The frequency distribution of the inspiratory three concave signs in the PB group was significantly greater than that in the non-PB group. Compared with those in the non-PB group, the number of patients with abnormally elevated of D-D dimer, LDH, ALT, and AST in the PB group was significantly greater. Mycoplasma pneumoniae (MP) was the main pathogen observed in both the PB and non-PB groups. In cases of MP infection without plastic bronchitis, treatment with macrolide antibiotics occurred significantly earlier. Most cases of pleural effusion in the PB-MP group were discovered more than 7 days after onset. However, in the PB-nonMP group, most cases of pleural effusion were detected within 7 days of onset. There was a difference observed in the distribution of pulmonary necrosis between the PB group and the non-PB group.ConclusionsMP is a common pathogen observed in PB cases caused by single-pathogen infections and multiple-pathogen infections. PB may be a potential cause of pulmonary necrosis. Furthermore, PB exhibits diverse clinical manifestations due to host and pathogen factors.

Release your inhibitions: The cell biology of GABAergic postsynaptic plasticity.

GABAergic synaptic inhibition controls circuit function by regulating neuronal plasticity, excitability, and firing. To achieve these goals, inhibitory synapses themselves undergo several forms of plasticity via diverse mechanisms, strengthening and weakening phasic inhibition in response to numerous activity-induced stimuli. These mechanisms include changing the number and arrangement of functional GABAARs within the inhibitory postsynaptic domain (iPSD), which can profoundly regulate inhibitory synapse strength. Here, we explore recent advances in our molecular understanding of inhibitory postsynaptic plasticity, with a focus on modulation of the trafficking, protein-protein interactions, nanoscale-organization, and posttranscriptional regulation of GABAARs and iPSD proteins. What has emerged is a complex mechanistic picture of how synaptic inhibition is controlled, with critical ramifications for cognition under typical and pathogenic conditions.

A sweeping view of avian mycoplasmas biology drawn from comparative genomic analyses

BackgroundAvian mycoplasmas are small bacteria associated with several pathogenic conditions in many wild and poultry bird species. Extensive genomic data are available for many avian mycoplasmas, yet no comparative studies focusing on this group of mycoplasmas have been undertaken so far.ResultsHere, based on the comparison of forty avian mycoplasma genomes belonging to ten different species, we provide insightful information on the phylogeny, pan/core genome, energetic metabolism, and virulence of these avian pathogens. Analyses disclosed considerable inter- and intra-species genomic variabilities, with genome sizes that can vary by twice as much. Phylogenetic analysis based on concatenated orthologous genes revealed that avian mycoplasmas fell into either Hominis or Pneumoniae groups within the Mollicutes and could split into various clusters. No host co-evolution of avian mycoplasmas can be inferred from the proposed phylogenetic scheme. With 3,237 different gene clusters, the avian mycoplasma group under study proved diverse enough to have an open pan genome. However, a set of 150 gene clusters was found to be shared between all avian mycoplasmas, which is likely encoding essential functions. Comparison of energy metabolism pathways showed that avian mycoplasmas rely on various sources of energy. Superposition between phylogenetic and energy metabolism groups revealed that the glycolytic mycoplasmas belong to two distinct phylogenetic groups (Hominis and Pneumoniae), while all the arginine-utilizing mycoplasmas belong only to Hominis group. This can stand for different evolutionary strategies followed by avian mycoplasmas and further emphasizes the diversity within this group. Virulence determinants survey showed that the involved gene arsenals vary significantly within and between species, and could even be found in species often reported apathogenic. Immunoglobulin-blocking proteins were detected in almost all avian mycoplasmas. Although these systems are not exclusive to this group, they seem to present some particular features making them unique among mycoplasmas.ConclusionThis comparative genomic study uncovered the significant variable nature of avian mycoplasmas, furthering our knowledge on their biological attributes and evoking new hallmarks.

Relationship of Autophagic Dysfunction With the Quality of Life and Sleep, Depression and Disease Severity in Patients With Restless Legs Syndrome.

Restless legs syndrome (RLS) is a frequently encountered neurological illness that has no effective treatment and imposes an enormous socioeconomic burden. Autophagy is essential for the maintenance of healthy cellular physiology, cell viability, and defense against pathogenic conditions. However, there is no study investigating the possible role of autophagy-related proteins (ATGs) in RLS patients. Therefore, we aimed to investigate the expression and diagnostic potential of ATG3 and ATG5, as well as the relationships between these proteins and laboratory markers, depression, disease score, quality of life, and sleep in RLS patients. A total of 49 patients with RLS and 26 healthy individuals were recruited for the current study. The severity of the disease was assessed using the international RLS rating scale. All participants were administered the Pittsburgh Sleep Quality Index, the Quality-of-Life Scale, and the Beck Depression Inventory. The enzyme-linked immunosorbent assay was employed to quantify the expressions of ATG3 and ATG5. Serum ATG3 and ATG5 expressions were significantly upregulated in RLS patients compared to healthy controls (p = 0.005) and upregulated ATG3 and ATG5 expressions were relationship with the severity of the disease (p < 0.05). ATG3 was substantially correlated with the quality of sleep, whereas ATG5 was correlated with the quality of life and depression status (p < 0.05). The ROC curve analysis demonstrated that ATG3 expressions over 3146.5ng/mL and ATG5 expressions over 4732.5ng/mL may predict the presence of RLS (p < 0.01). We report for the first time that autophagy may have a significant impact on the development of RLS.

Systematic literature review on Calcium Pyrophosphate Deposition (CPPD) nomenclature: condition elements and clinical states— A Gout, Hyperuricaemia and Crystal-Associated Disease Network (G-CAN) consensus project

ObjectivesThe Gout, Hyperuricaemia and Crystal-Associated Disease Network (G-CAN) has developed a calcium pyrophosphate deposition (CPPD) nomenclature project. This systematic literature review constituted its first step and aimed to provide a...

Activation of S1PR2 on macrophages and the hepatocyte S1PR2/RhoA/ROCK1/MLC2 pathway in vanishing bile duct syndrome.

Immunologic bile duct destruction is a pathogenic condition associated with vanishing bile duct syndrome (VBDS) after liver transplantation and hematopoietic stem-cell transplantation. As the bile acid receptor sphingosine 1-phosphate receptor 2 (S1PR2) plays a critical role in recruitment of bone marrow-derived monocytes/macrophages to sites of cholestatic liver injury, S1PR2 expression was examined using cultured macrophages and patient tissues. Bile canaliculi destruction precedes intrahepatic ductopenia; therefore, we focused on hepatocyte S1PR2 and the downstream RhoA/Rho kinase 1 (ROCK1) signaling pathway and bile canaliculi alterations using three-dimensional hepatocyte culture models that form obvious bile canaliculus-like networks. Multiplex immunohistochemistry revealed increased numbers of S1PR2+CD45+CD68+FCN1+ inflammatory macrophages and S1PR2+CD45+CD68+MARCO+ Kupffer cells in liver tissues showing ductopenia due to graft-versus-host disease and rejection post-liver transplant compared with normal liver. Macrophage expression of proinflammatory cytokines, including MCP1, was reduced following S1PR2 inhibition. Taurocholic acid and S1P2 agonist induced hepatocyte S1PR2 and reduced RhoA/ROCK1 expression, resulting in bile canaliculi dilatation. S1PR2 inhibition reversed the effect on RhoA/ROCK1 expression, resulting in maintenance of bile canaliculi through myosin light chain 2 (MLC2) phosphorylation. Activation of S1PR2 on macrophages and S1PR2 on hepatocytes may disrupt bile canaliculi dynamics in VBDS under regulation by RhoA/ROCK1 through MLC2 phosphorylation.

Bioinspired programmable coacervate droplets and self-assembled fibers through pH regulation of monomers.

Phase separation and phase transitions pervade the biological domain, where proteins and RNA engage in liquid-liquid phase separation (LLPS), forming liquid-like membraneless organelles. The misregulation or dysfunction of these proteins culminates in the formation of solid aggregates via a liquid-to-solid transition, leading to pathogenic conditions. To decipher the underlying mechanisms, synthetic LLPS has been examined through complex coacervate formation from charged polymers. Nonetheless, temporal control over phase transitions from prebiotically relevant small organic synthons remains largely unexplored. Herein, we propose utilizing pH modulation to regulate the charge of small molecular building blocks, thereby controlling the LLPS process. Through a bio-inspired, enzyme-mediated pH-regulated reaction, we introduce temporal control over both LLPS and the transition from coacervates to supramolecular polymers. Additionally, by incorporating antagonistic pH modulators, we achieve transient LLPS and further temporal regulation of supramolecular polymer disassembly. Our investigation into pH-regulated LLPS provides a new avenue for exploring the stimuli-responsive, dynamic, and transient nature of LLPS.

The N-terminal domain of gasdermin D induces liver fibrosis by reprogrammed lipid metabolism.

The emerging incidence of pathogenic liver conditions is turning into a major concern for global health. Induction of pyroptosis in hepatocytes instigates cellular disintegration, which in turn liberates substantial quantities of pro-inflammatory intracellular substances, thereby accelerating the advancement of liver fibrosis. Consequently, directing therapeutic efforts towards inhibiting pyroptosis could potentially serve as an innovative approach in managing inflammation related chronic hepatic disorders. GSDMD-NTki/wt mice and Alb-creki/wt mice were generated using CRISPR/Cas9 technology. After crossing the two strains together, we induced conditional cell death by doxycycline to construct a mouse model of liver fibrosis. We analyzed differentially expressed genes by RNA sequencing and explored their biological functions. The efficacy of obeticholic acid (OCA) in the treatment of liver fibrosis was assessed. Doxycycline-treated GSDMD-NTki/wt × Alb-creki/wt mice showed severe liver damage, vacuolation of hepatocytes, increased collagen fibers, and accumulation of lipid droplets. The expression of liver fibrosis related genes was greatly increased in the doxycycline-treated mouse liver compared with untreated mouse liver. RNA-sequencing showed that upregulated differentially expressed genes were involved in inflammatory responses, cell activation, and metabolic processes. Treatment with OCA alleviated the liver fibrosis, with reduced ALT and AST levels seen in the GSDMD-NTki/wt × Alb-creki/wt mice. We successfully constructed a novel mouse model for liver fibrosis. This GSDMD-NT-induced fibrosis may be mediated by abnormal lipid metabolism. Our results demonstrated that we successfully constructed a mouse model of liver fibrosis, and GSDMD-NT induced fibrosis by mediating lipid metabolism.

Quercetin Ameliorates Acute Lethal Sepsis in Mice by Inhibiting Caspase-11 Noncanonical Inflammasome in Macrophages.

Quercetin is a natural polyphenolic flavonoid widely found in plants, fruits, and vegetables, and has been reported to play pharmacological roles in numerous pathogenic conditions. The anti-inflammatory effects of quercetin in various inflammatory conditions and diseases have been well-documented. However, its regulatory role in noncanonical inflammasome activation has not yet been demonstrated. This study investigated the anti-inflammatory effects of quercetin in caspase-11 noncanonical inflammasome-activated inflammatory responses in macrophages and a mouse model of acute lethal sepsis. Quercetin protected J774A.1 macrophages from lipopolysaccharide (LPS)-induced cell death and caspase-11 noncanonical inflammasome-induced pyroptosis. It significantly decreased the production and mRNA expression of pro-inflammatory cytokines, such as interleukin (IL)-1β, IL-18, and IL-6, but not tumor necrosis factor (TNF)-α, and inflammatory molecules, such as nitric oxide (NO) and inducible NO synthase in caspase-11 noncanonical inflammasome-activated J774A.1 cells. Mechanistically, quercetin strongly suppressed the autoproteolysis and secretion of caspase-11 and the proteolysis of gasdermin D in caspase-11 noncanonical inflammasome-activated J774A.1 cells. However, quercetin did not inhibit the direct binding of caspase-11 to LPS. In vivo, the study revealed that quercetin increased the survival rate of mice with acute lethal sepsis and decreased serum levels of pro-inflammatory cytokines without causing significant toxicity. In conclusion, this study highlights quercetin-mediated anti-inflammatory action in inflammatory responses and acute lethal sepsis through a novel mechanism that targets the caspase-11 noncanonical inflammasome in macrophages, suggesting quercetin as a promising anti-inflammatory agent in natural medicine.

MAN2B1 in immune system-related diseases, neurodegenerative disorders and cancers: functions beyond α-mannosidosis.

Glycosylation modifications of proteins and glycan hydrolysis are critical for protein function in biological processes. Aberrations in glycosylation enzymes are linked to lysosomal storage disorders (LSDs), immune interactions, congenital disorders and tumour progression. Mannosidase alpha class 2B member 1 (MAN2B1) is a lysosomal hydrolase from the α-mannosidase family. Dysfunction of MAN2B1 has been implicated as causative factors in mannosidosis, a lysosomal storage disorder characterised by cognitive impairment, hearing loss and immune system and skeletal anomalies. Despite decades of research, its role in pathogenic infections, autoimmune conditions, cancers and neurodegenerative pathologies is highly ambiguous. Future studies are required to shed more light on the intricate functioning of MAN2B1. To this end, we review the biological functions, expression patterns, enzymatic roles and potential implications of MAN2B1 across various cell types and disease contexts. Additionally, the novel insights presented in this review may aid in understanding the role of MAN2B1 in immune cells, thereby paving the way for targeted therapeutic interventions in immune-related disorders.

Evaluating Trichoderma-containing Biofungicide and Grafting for Productivity and Plant Health of Triploid Seedless Watermelon in California’s Commercial Production

Two field experiments were carried out in 2022 and 2023 within commercial watermelon fields in Stockton and Modesto, CA, USA. Two Trichoderma-containing products were applied to the grafted and nongrafted watermelon seedlings through tray soaking or field chemigation. All seedlings were mechanically transplanted into a split-split plot design with the Trichoderma product as the main factor and application method (tray soaking and chemigation) as the sub-plot. The sub-sub-factor included three interspecific hybrid squash rootstocks (Cucurbita maxima × Cucurbita moschata) ‘Cobalt’, ‘Flexifort’, and ‘RS841’ that were grafted with the commercial seedless watermelon scion ‘Summer Breeze’. All treatments were replicated four times. Vine health was visually assessed three times, and canopy coverage was assessed for a total of six measurements for each year. Harvest was conducted three times in 2022 and twice in 2023 to analyze yield and quality differences among treatments. Aboveground and root samples from defective plants were taken amid the harvest and shipped to the University of California, Davis Fungal Pathology Diagnostics Research Laboratory for identification of soilborne fungal pathogens to confirm or rule out their involvement in vine declines initially attributed to nonpathogenic factors. The laboratory diagnosis indicated that Macrophomina was morphologically identified from the foot and root isolations of 67% of the submitted nongrafted, non-Trichoderma-biofungicide–treated plants in 2022. Further sequencing results confirmed the primary pathogen, Macrophomina phaseolina, from 50% of those submitted plant samples. In addition, putative Fusarium root and stem rot (Fusarium oxysporum f. sp. radices-cucurmerinum) and Falciforme crown rot and decline (Fusarium noneumartii) from runners and roots of nongrafted, noninoculated plants in the 2022 experiment were also reported. However, no significant soilborne fungal pathogens were found in the 2023 experiment. In both trials, the effects of Trichoderma-containing biofungicides and their application methods on preventing vine decline, maintaining canopy coverage, and enhancing fruit yield and quality were not as remarkable as grafting. The average grafting effect contributed to 83% and 53% decrease of vine decline compared with the nongrafted plants in 2022 and 2023. Overall, grafted plants yielded 47.6% and 32.4% more than the nongrafted counterpart in 2022 and 2023, respectively. In addition, grafting exerted predominant influence on fruit firmness and rind thickness. The study results indicated that grafting onto multipathogen resistance watermelon rootstocks serves as an effective production tool to maintain fruit yield, quality, and plant health under both pathogenic and disease-free conditions. Further work is still needed to continue evaluating best practical application protocols of Trichoderma-based biofungicides and other biopesticides to enhance product effectiveness and end users’ confidence in reducing soilborne diseases and reliance on conventional fumigants.

Effects of cotton peanut rotation on crop yield soil nutrients and microbial diversity

Background and Aims Cotton-peanut rotation is a sustainable farming practice that enhances land utilization and promotes the sustainable development of agriculture. Crop rotation can reduce the occurrence of pests and diseases, as different crops have varying levels of resistance to such threats. Additionally, by alternating the types of crops grown, the soil environment is changed, which can lead to the elimination of favorable conditions for pathogens and pests, thereby alleviating the impact of these issues. Furthermore, cotton-peanut rotation can improve soil fertility.To investigate the effects of different crop rotation systems on crop yield, soil nutrients, and soil microbial communities. Methods: Using high-throughput sequencing technology, investigate the soil microbial diversity in the root zone after cotton-peanut rotation.Various planting patterns, including cotton continuous cropping (MC), peanut continuous cropping (HC), peanut-cotton-peanut rotation (HR), and fallow (X), were established to assess variations in crop yield, soil nutrients, and soil microbial diversity. Results: Significant differences were observed in crop yield, soil nutrients, and soil microbial community structure among different planting patterns. The HR system significantly increased the output compared with the HC and MC systems. Additionally, HR exhibited significantly lower total nitrogen (N) and basic nitrogen (BN) contents than HC and MC, whereas MC showed lower total potassium (K) and available potassium (AK) contents. HR led to a decrease in soil bacterial diversity but an increase in fungal diversity, with Ascomycota and Mortierellomycota being dominant. Various bacteria (Chloroflexi, Bacteroidota, and Actinobacteriota) associated with organic matter degradation and nutrient cycling were found across different planting systems, enhancing material cycling efficiency. Furthermore, Planctomycetota bacteria related to crop nutrient synthesis and Glomeromycota bacteria aiding plant nutrient absorption were significantly higher in the MC system than in the HR or HC systems. Redundancy analysis indicated a significant negative correlation between crop rotation and soil fungal community, whereas Ascomycota exhibited a significant negative correlation with organic matter.Conclusion: Peanut-cotton rotation can mitigate soil nutrient loss, enhance beneficial microorganism diversity, suppress harmful bacterial populations, stabilize ecosystems, and boost crop yield.

Complete genome of single locus sequence typing D1 strain Cutibacterium acnes CN6 isolated from healthy facial skin.

Cutibacterium acnes is a Gram-positive bacterium commonly found on human skin, particularly in sebaceous areas. While it is typically considered a commensal, specific strain types based on single locus sequence typing (SLST) have been associated with pathogenic conditions or healthy skin. Recently, SLST D1 strains, part of phylotype IA1, have received attention for their potential benefits related to skin health. However, their genetic characteristics remain underexplored. Therefore, the whole genome of C. acnes CN6, an SLST D1 strain isolated from the facial skin of a healthy individual, was sequenced to expand the understanding of SLST D1 strains and identify genomic features that may support skin health. The whole genome sequencing of C. acnes CN6 was conducted using MinION reads based on de novo assembly, revealing a single circular complete chromosome. With the length of 2,550,458bp and G + C content of 60.04%, the genome contains 2,492 genes, including 2,433 CDSs, 9 rRNAs, 46 tRNAs, 4 ncRNAs, and 134 pseudo genes. Previously predicted virulence proteins of C. ances were detected in the genome. Genome comparation with 200 C. acnes strains isolated from healthy facial skin revealed SLST D1 strain-specific genes and a unique variant of the znuC gene in D1 strains.

Unleashing the relationship between climate change and infectious diseases

Climate change is rapidly emerging as a powerful driver of human health, understanding the relation between infectious disease dynamics and climate change is crucial for public health, particularly in developing nations. This article review delves into the intricate relationship between climate change and infectious diseases, with a particular focus on how climate factors are influencing the spread of vector borne diseases and water borne diseases such as prevalent diseases like malaria, cholera, and dengue in India. The objective is to assess the relationship between climate change and the burden of infectious diseases, with a focus on understanding how climate factors influence the prevalence and spread of infectious diseases. A literature search using PubMed, Science Direct, and government and international health reports focused on the terms 'climate change', 'infectious diseases' and 'health impact’. The review highlights that climate change accelerates vector lifecycles and creates favourable conditions for pathogens, leading to more frequent and severe outbreaks. Extreme weather events are worsening these risks, leading to more frequent and severe outbreaks. This poses a growing threat to global health, particularly in vulnerable regions like India. Despite government efforts, significant challenges remain. Strengthening healthcare infrastructure, improving disease surveillance, and adopting climate-resilient practices are essential to safeguard vulnerable populations and mitigate the impact of climate change on public health.

Detection of viral agents associated with Porcine Respiratory Disease Complex (PRDC) in pigs in North Kerala

In pigs, stress factors such as pathogenic infections, environmental conditions, and various managemental practices can lead to a disease condition known as Porcine respiratory disease complex (PRDC). The main viral agents associated with this condition are Porcine circovirus 2 (PCV2), Porcine reproductive and respiratory syndrome virus (PRRSV), swine influenza virus (SIV), porcine respiratory coronavirus (PRCV), and pseudorabies virus. A study was undertaken to assess whether PCV2 and PRRSV, alone or in combination, are present in cases of respiratory ailments of pigs in North Kerala. The presence of PCV2 was detected by polymerase chain reaction (PCR) targeting the open reading frame 2 (ORF2) of the virus and PRRSV was detected by reverse transcriptase PCR (RT-PCR) targeting ORF6. A total of 54 tissue and lung samples were collected and screened for the presence of PCV2 and PRRSV. Of the samples tested, PCV2 could be detected in 22 (40.74 %) and PRRSV could be detected in 13 (24.07 %) samples. Two tissue samples showed mixed infections with PCV2 and PRRSV. The result shows that viral agents associated with PRDC are prevalent in pigs in North Kerala and that coinfections are also present. Keywords: Porcine respiratory disease complex, Porcine circovirus 2, Porcine reproductive and respiratory syndrome virus, polymerase chain reaction

The role of NETosis in enhancing of atherosclerosis.

Activated neutrophils release neutrophil extracellular traps (NETs), complex structures composed of extracellular genetic material and proteins sourced from the nucleus, granules, and cytoplasm in response to pathogenic inflammatory conditions. These NETs play a crucial role in the host's innate immune defense against invasive infections. Notably, in conditions like atherosclerosis, these extracellular formations can also be elicited by inflammatory stimuli such as lipids, prothrombotic factors, platelet aggregation, or proinflammatory cytokines. NETs have been identified on the inner arterial walls in cardiovascular disease states. By promoting inflammation through NETosis-mediated cell adhesion processes and exerting cytotoxic effects leading to cellular dysfunction and tissue damage, NETs contribute to the pathogenesis of inflammatory conditions.

Microglia-mediated neuron death requires TNF and is exacerbated by mutant Huntingtin

Microglia, the resident immune cells of the brain, regulate the balance of inflammation in the central nervous system under healthy and pathogenic conditions. Huntington’s disease (HD) is a chronic neurodegenerative disease characterized by activated microglia and elevated concentrations of pro-inflammatory cytokines within the brain. Chronic hyperactivation of microglia is associated with brain pathology and eventual neuron death. However, it is unclear which specific cytokines are required for neuron death and whether HD neurons may be hypersensitive to neuroinflammation. We assessed the profile of microglia-secreted proteins in response to LPS and IFNγ, and a conditioned media paradigm was used to examine the effects of these secreted proteins on cultured neuronal cells. STHdhQ7/Q7 and STHdhQ111/Q111 neuronal cells were used to model wild-type and HD neurons, respectively. We determined that STHdhQ111/Q111 cells were hypersensitive to pro-inflammatory factors secreted by microglia, and that TNF was required to induce neuronal death. Microglia-mediated neuronal death could be effectively halted through the use of JAK-STAT or TNF inhibitors which supported the requirement for TNF as well as IFNγ in the process of secondary neurotoxicity. Further data derived from human HD patients as well as HD mice were suggestive of enhanced receptor density for TNF (TNFR1) and IFNγ (IFNGR) which could sensitize the HD brain to these cytokines. This highlights several potential mechanisms by which microglia may induce neuronal death and suggests that these mechanisms may be upregulated in the brain of HD patients.

OBTAINING TRANSGENIC POTATO PLANTS FOR COUNTERING PHYTOPHTHORA INFESTANS VIA “HIGS” METHOD IMPLEMENTATION

Oomycetes are a group of organisms that include some of the most dangerous plant pathogens capable of causing epiphytoties that lead to reduced crop yields and famine in some countries. The only available method of combating them – repeated application of fungicides in fields and careful selection of seed material – is ineffective for most of these pathogens. This paper proposes to use the HIGS (host-induced gene silencing) approach so that genetically modified plants, when infected with late blight, would cause the pathogen to silence its effector protein genes, which would prevent the pathogen from growing and reproducing in plant. To implement the HIGS method against the pathogen Phytophthora infestans, we developed two genetically engineered constructs, one of which uses the P. infestans RXLR-effector gene AVR3a-b as the RNA interference target, and the other uses a region of the PITG_03155 effector gene, which is conserved for both P. infestans and P. cactorum. After Agrobacterium-mediated genetic transformation of potato plants, we obtained four transgenic plants carrying a construct based on the AVR3a-b gene (two each of the “Milena” and “Gala” varieties) and one of “Milena” variety carrying a construct based on the PITG_03155 gene. These plants will be micro clonally propagated and tested for the presence of interfering RNA to the effector genes of P. infestans, after which the plant lines are planned to be planted under natural pathogenic background conditions and a comparative analysis with control plants for disease incidence and resistance will be conducted.

Application of Single Cell Type-Derived Spheroids Generated by Using a Hanging Drop Culture Technique in Various In Vitro Disease Models: A Narrow Review.

Cell culture methods are indispensable strategies for studies in biological sciences and for drug discovery and testing. Most cell cultures have been developed using two-dimensional (2D) culture methods, but three-dimensional (3D) culture techniques enable the establishment of in vitro models that replicate various pathogenic conditions and they provide valuable insights into the pathophysiology of various diseases as well as more precise results in tests for drug efficacy. However, one difficulty in the use of 3D cultures is selection of the appropriate 3D cell culture technique for the study purpose among the various techniques ranging from the simplest single cell type-derived spheroid culture to the more sophisticated organoid cultures. In the simplest single cell type-derived spheroid cultures, there are also various scaffold-assisted methods such as hydrogel-assisted cultures, biofilm-assisted cultures, particle-assisted cultures, and magnet particle-assisted cultures, as well as non-assisted methods, such as static suspension cultures, floating cultures, and hanging drop cultures. Since each method can be differently influenced by various factors such as gravity force, buoyant force, centrifugal force, and magnetic force, in addition to non-physiological scaffolds, each method has its own advantages and disadvantages, and the methods have different suitable applications. We have been focusing on the use of a hanging drop culture method for modeling various non-cancerous and cancerous diseases because this technique is affected only by gravity force and buoyant force and is thus the simplest method among the various single cell type-derived spheroid culture methods. We have found that the biological natures of spheroids generated even by the simplest method of hanging drop cultures are completely different from those of 2D cultured cells. In this review, we focus on the biological aspects of single cell type-derived spheroid culture and its applications in in vitro models for various diseases.

Occurrence of pathogenic Mycobacteria avium and Pseudomonas aeruginosa in outdoor decorative fountain water and the associated microbial community.

Outdoor decorative fountains usually attract residents to visit. However, opportunistic pathogens (OPs) can proliferate and grow in the stagnant fountain water, posing potential health risks to visitors due to the inhalation of spaying aerosols. In this study, the abundance of selected OPs and associated microbial communities in three large outdoor decorative fountain waters were investigated using quantitative PCR and 16S rRNA sequencing. The results indicated that Mycobacteria avium and Pseudomonas aeruginosa were consistently detected in all decorative fountain waters throughout the year. Redundancy analysis showed that OPs abundance was negatively correlated with water temperature but positively correlated with nutrient concentrations. The gene copy numbers of M. avium varied between 2.4 and 3.9 log10 (gene copies/mL), which were significantly lower than P. aeruginosa by several orders of magnitude, reaching 6.5-7.1 log10 (gene copies/mL) during winter. The analysis of taxonomic composition and prediction of functional potential also revealed pathogenic microorganisms and infectious disease metabolic pathways associated with microbial communities in different decorative fountain waters. This study provided a deeper understanding of the pathogenic conditions of the outdoor decorative fountain water, and future works should focus on accurately assessing the health risks posed by OPs in aerosols.