ABSTRACT
BACKGROUND: Cryptococcosis is a life-threatening infection is primarily caused by two sibling species Cryptococcus neoformans and Cryptococcus gattii. Several virulence-related factors of these cryptococci have been widely investigated in Caenorhabditis elegans, representing a facile in vivo model of host-pathogen interaction. While recent studies elucidated cryptococcal virulence factors, intrinsic host factors that affect susceptibility to infections by cryptococci remain unclear and poorly investigated. RESULTS: Here, we showed that defects in C. elegans insulin/insulin-like growth factor-1 (IGF-1) signaling (IIS) pathway influenced animal lifespan and mechanisms of host resistance in cryptococcal infections, which required the activation of aging regulator DAF-16/Forkhead box O transcription factor. Moreover, accumulation of lipofuscin, DAF-16 nuclear localization, and expression of superoxide dismutase (SOD-3) were elevated in C. elegans due to host defenses during cryptococcal infections. CONCLUSION: The present study demonstrated the relationship between longevity and immunity, which may provide a possibility for novel therapeutic intervention to improve host resistance against cryptococcal infections.
Subject(s)
Caenorhabditis elegans Proteins , Cryptococcosis , Cryptococcus gattii , Cryptococcus neoformans , Forkhead Transcription Factors , Animals , Caenorhabditis elegans/microbiology , Caenorhabditis elegans/physiology , Caenorhabditis elegans Proteins/genetics , Cryptococcus gattii/pathogenicity , Cryptococcus neoformans/pathogenicity , Forkhead Transcription Factors/genetics , Immunity , Longevity , Virulence Factors/metabolismABSTRACT
Invasive aspergillosis and scedosporiosis are life-threatening fungal infections with similar clinical manifestations in immunocompromised patients. Contrarily, Scedosporium apiospermum is susceptible to some azole derivative but often resistant to amphotericin B. Histopathological examination alone cannot diagnose these two fungal species. Pathogenesis studies could contribute to explore candidate protein markers for new diagnosis and treatment methods leading to a decrease in mortality. In the present study, proteomics was conducted to identify significantly altered proteins in A549 cells infected with or without Aspergillus fumigatus and S. apiospermum as measured at initial invasion. Protein validation was performed with immunogold labelling alongside immunohistochemical techniques in infected A549 cells and lungs from murine models. Further, cytokine production was measured, using the Bio-Plex-Multiplex immunoassay. The cytoskeletal proteins HSPA9, PA2G4, VAT1, PSMA2, PEX1, PTGES3, KRT1, KRT9, CLIP1 and CLEC20A were mainly changed during A. fumigatus infection, while the immunologically activated proteins WNT7A, GAPDH and ANXA2 were principally altered during S. apiospermum infection. These proteins are involved in fungal internalisation and structural destruction leading to pulmonary disorders. Interleukin (IL)-21, IL-1α, IL-22, IL-2, IL-8, IL-12, IL-17A, interferon-γ and tumour necrosis factor-α were upregulated in both aspergillosis and scedosporiosis, although more predominately in the latter, in accordance with chitin synthase-1 and matrix metalloproteinase levels. Our results demonstrated that during invasion, A. fumigatus primarily altered host cellular integrity, whereas S. apiospermum chiefly induced and extensively modulated host immune responses.
Subject(s)
Aspergillus fumigatus , Cytoskeleton/microbiology , Epithelium/microbiology , Mycoses , Scedosporium , A549 Cells , Animals , Humans , Lung , MiceABSTRACT
Candida albicans can cause infections ranging from superficial skin infections to life-threateningsystemic infections in immunocompromised hosts. Although several C. albicans virulence factorsare widely discussed in great detail, intrinsic host determinants that are critical for C. albicanspathogenesis remain less interested and poorly understood. In view of this, a model of Caenorhabditiselegans was used to study host longevity and immunity in response to C. albicans pathogenesis.The influence of C. albicans in pathological and survival aspects was evaluated using C. elegans.C. albicans hyphal formation in different C. elegans genetic backgrounds was evaluated. Moreover,several C. elegans fluorescent proteins as gene expression markers upon C. albicans infectionswere evaluated. C. albicans is pathogenic to C. elegans and reduces the lifespan of C. elegans inassociation with repression of the insulin/IGF-1-like signaling (IIS) pathway. Moreover, repressionof DAF-16/forkhead transcription factor increases aggressiveness of C. albicans by enhancing hyphalformation. In addition, infection of C. albicans increases lipofuscin accumulation, promotes DAF-16nuclear translocation, increases superoxide dismutase (SOD-3) expression, which coordinately linksbetween aging and innate immunity. Thus, we demonstrate here the strategy to utilize C. elegans asa model host to elucidate host genetic determinants that provide insights into the pathogenesis ofC. albicans infections.
Subject(s)
Caenorhabditis elegans Proteins , Candidiasis , Forkhead Transcription Factors , Animals , Caenorhabditis elegans/genetics , Caenorhabditis elegans/immunology , Caenorhabditis elegans/microbiology , Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans Proteins/metabolism , Candida albicans , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/metabolism , Immunity, Innate , Insulin/genetics , Insulin/metabolism , Longevity/genetics , MutationABSTRACT
The noncontagious immune-mediated skin disease known as psoriasis is regarded as a chronic skin condition with a 0.09-11.4% global prevalence. The main obstacle to the eradication of the disease continues to be insufficient treatment options. Sericin, a natural biopolymer from Bombyx mori cocoons, can improve skin conditions via its immunomodulatory effect. Many external therapeutic methods are currently used to treat psoriasis, but sericin-based hydrogel is not yet used to treat plaques of eczema. Through the use of an imiquimod rat model, this study sought to identify the physical and chemical characteristics of a silk sericin-based poly(vinyl) alcohol (SS/PVA) hydrogel and assess both its therapeutic and toxic effects on psoriasis. The cytokines, chemokines, and genes involved in the pathogenesis of psoriasis were investigated, focusing on the immuno-pathological relationships. We discovered that the SS/PVA had a stable fabrication and proper release. Additionally, the anti-inflammatory, antioxidant, and anti-apoptotic properties of SS/PVA reduced the severity of psoriasis in both gross and microscopic skin lesions. This was demonstrated by a decrease in the epidermal histopathology score, upregulation of nuclear factor erythroid 2-related factor 2 and interleukin (IL)-10, and a decrease in the expression of tumor necrosis factor (TNF)-α and IL-20. Moreover, the genes S100a7a and S100a14 were downregulated. Additionally, in rats given the SS/PVA treatment, blood urea nitrogen, creatinine, and serum glutamic oxaloacetic transaminase levels were within normal limits. Our findings indicate that SS/PVA is safe and may be potentiated to treat psoriasis in a variety of forms and locations of plaque because of its physical, chemical, and biological characteristics.
Subject(s)
Psoriasis , Sericins , Rats , Animals , Sericins/pharmacology , Sericins/therapeutic use , Sericins/chemistry , Polyvinyl Alcohol/chemistry , Psoriasis/drug therapy , Hydrogels , BandagesABSTRACT
Soil fungal communities play an important role in regulating biogeochemical transformations, yet soil-related fungal pathogens are emerging threats to humans. Our previous studies have revealed the pathogenic Scedosporium species in soils samples from public parks with high human activities in Thailand. However, measurement and survey of soil fungal communities in other areas with high human/animal activities, such as the pigsty, are poorly determined. In this study, soil fungal pathogens from a pigsty were isolated and identified. Soil samples were collected from the surrounding drainage areas. Fungal species were identified using morphological and molecular analyses. Isolation of soil samples from the pigsty revealed at least 11 species that have been identified. The most abundant fungal species belonged to genera Aspergillus and Penicillium. Moreover, Scedo-Select III culturing and phylogenetic analysis with ß-tubulin gene sequencing revealed the three environmental isolates of Scedosporium species, which were consistent with the S.apiospermum. These three Scedosporium isolates were susceptible to voriconazole and caused pathological characteristics of scedosporiosis similar to S. apiospermum in vivo. In conclusion, our findings contribute towards a better understanding of soil-borne pathogenic fungi in the pigsty. The isolation of Scedosporium species with pathogenic potentials in the present study can be beneficial for the management of public health surveillance, epidemiologists, as well as physicians to reduce the risk of soil fungal contamination among pigsty workers.
Subject(s)
Mycobiome , Scedosporium , Antifungal Agents/pharmacology , Humans , Invasive Fungal Infections , Phylogeny , Scedosporium/genetics , ThailandABSTRACT
Candida albicans is an opportunistic fungal infectious agent that can cause cutaneous candidiasis in humans. Biofilms formation of C. albicans is thought to be the major cause of antifungal drug resistance. Despite numerous studies conducted on C. albicans biofilms, a comprehensive understanding of how C. albicans biofilms induced cutaneous candidiasis in humans and the development of a more effective targeted therapy remain poorly investigated. Available animal models of cutaneous candidiasis and in vitro human skin cell cultures do not fully reflect the actual human skin microenvironment or the disease pathogenesis. We investigated the molecular pathology of C. albicans infection using an in vitro biofabricated 3D skin. This in vitro biofabricated 3D skin comprises a fully humanized three-dimensional (3D) skin equivalent, consisting of a stratified terminally differentiated epidermis and an underlying dermal compartment. Antifungal drug susceptibility testing, histological and electron microscopy study, biofilms study, and pro-inflammatory cytokines analysis were conducted in C. albicans infected skin. Histological results revealed that C. albicans covered and produced biofilm on the in vitro biofabricated 3D skin, invading the skin compartments including epidermis and dermis. Elevation of proinflammatory cytokines including MMP-9, IL-1ß, TNF-α, and IL-5 were examined in the C. albicans infected skin. However, treatment with itraconazole reduced the pathology of C. albicans infection. This study provides an alternative pathological model of cutaneous candidiasis, which can physiologically represent a close-up event during C. albicans. Moreover, it is rapid, cost-effective, and reproducible of the in vitro biofabricated 3D skin model, and may further highlight the importance of utilizing in vivo-like conditions to improve high-throughput screening for drug discovery against several antifungal drug resistant pathogens.
Subject(s)
Antifungal Agents/pharmacology , Biofilms/drug effects , Candida albicans/drug effects , In Vitro Techniques , Skin, Artificial/microbiology , Candidiasis/drug therapy , Drug Resistance, Fungal , Humans , Microbial Sensitivity TestsABSTRACT
Knee osteoarthritis is a chronic joint disease mainly characterized by cartilage degeneration. The treatment is challenging due to the lack of blood vessels and nerve supplies in cartilaginous tissue, causing a prominent limitation of regenerative capacity. Hence, we investigated the cellular promotional and anti-inflammatory effects of sericin, Bombyx mori-derived protein, on three-dimensional chondrogenic ATDC5 cell models. The results revealed that a high concentration of sericin promoted chondrogenic proliferation and differentiation and enhanced matrix production through the increment of glycosaminoglycans, COL2A1, COL X, and ALP expressions. SOX-9 and COL2A1 gene expressions were notably elevated in sericin treatment. The proteomic analysis demonstrated the upregulation of phosphoglycerate mutase 1 and triosephosphate isomerase, a glycolytic enzyme member, reflecting the proliferative enhancement of sericin. The differentiation capacity of sericin was indicated by the increased expressions of procollagen12a1, collagen10a1, rab1A, periostin, galectin-1, and collagen6a3 proteins. Sericin influenced the differentiation capacity via the TGF-ß signaling pathway by upregulating Smad2 and Smad3 while downregulating Smad1, BMP2, and BMP4. Importantly, sericin exhibited an anti-inflammatory effect by reducing IL-1ß, TNF-α, and MMP-1 expressions and accelerating COL2A1 production in the early inflammatory stage. In conclusion, sericin demonstrates potential in promoting chondrogenic proliferation and differentiation, enhancing cartilaginous matrix synthesis through glycolysis and TGF-ß signaling pathways, and exhibiting anti-inflammatory properties.
Subject(s)
Cell Differentiation , Cell Proliferation , Chondrogenesis , Glycolysis , Inflammation , Sericins , Signal Transduction , Smad2 Protein , Smad3 Protein , Transforming Growth Factor beta , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Smad2 Protein/metabolism , Animals , Signal Transduction/drug effects , Smad3 Protein/metabolism , Transforming Growth Factor beta/metabolism , Chondrogenesis/drug effects , Sericins/pharmacology , Glycolysis/drug effects , Mice , Inflammation/metabolism , Inflammation/pathology , Inflammation/drug therapy , Chondrocytes/metabolism , Chondrocytes/drug effects , Cell Line , Bombyx/metabolismABSTRACT
Pigeon excreta can cause environmental and public health issues, particularly in urban and public areas. They are reservoirs of several human pathogens including fungi, bacteria, and viruses. Epidemiological data of pathogenic and opportunistic yeasts in pigeon droppings in Chon Buri, one of the most reputable tourist cities of Thailand, are scarce. The present study aimed to identify yeasts in pigeon droppings by MALDI-TOF mass spectrometry, and to study their prevalence in Chon Buri, Thailand. A total of 200 pigeon fecal samples were collected randomly from all 11 districts of Chon Buri. A sum of 393 yeast-like colonies were isolated on Sabourand's dextrose agar and CHROMagar media. These isolates were further confirmed for their species by MALDI-TOF MS. Twenty-four yeast species belonging to 11 different genera were identified in pigeon fecal samples. Candida spp., predominantly C. krusei (14.32%), were the most prevalent yeast species. Other yeast species, including C. glabrata (12.73%), C. metapsilosis (11.93%), Lodderomyces elongisporus (10.87%), C. tropicalis (7.16%), C. albicans (5.83%), and Cryptococcus neoformans (4.77%) were identified. This study provides valuable epidemiological data and diversity of yeasts in pigeon droppings in Chon Buri, Thailand, and also supports the use of MALDI-TOF MS for yeast identification and epidemiological surveillance.
Subject(s)
Columbidae , Cryptococcus neoformans , Animals , Humans , Columbidae/microbiology , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Prevalence , Thailand , Yeasts , Candida albicansABSTRACT
Candidemia is often associated with high mortality, and Candida albicans, Candida tropicalis, Candida glabrata, and Candida parapsilosis are common causes of this disease. The pathogenicity characteristics of specific Candida spp. that cause candidemia in Thailand are poorly understood. This study aimed to characterize the virulence factors of Candida spp. Thirty-eight isolates of different Candida species from blood cultures were evaluated for their virulence properties, including exoenzyme and biofilm production, cell surface hydrophobicity, tissue invasion, epithelial cell damage, morphogenesis, and phagocytosis resistance; the identity and frequency of mutations in ERG11 contributing to azole-resistance were also determined. C. albicans had the highest epithelial cell invasion rate and phospholipase activity, with true hyphae formation, whereas C. tropicalis produced the most biofilm, hydrophobicity, protease activity, and host cell damage and true hyphae formation. ERG11 mutations Y132F and S154F were observed in all azole-resistant C. tropicalis. C. glabrata had the most hemolytic activity while cell invasion was low with no morphologic transition. C. glabrata was more easily phagocytosed than other species. C. parapsilosis generated pseudohyphae but not hyphae and did not exhibit any trends in exoenzyme production. This knowledge will be crucial for understanding the pathogenicity of Candida spp. and will help to explore antivirulence-based treatment.
ABSTRACT
Tryptophol (TOH), a fungal quorum-sensing molecule, that possesses anti-fungal activities for controlling the growth of human pathogenic fungi. In the present study, we developed TOH-containing emulgel formulations and examined the antifungal activities and potential use as topical treatments on the skin. The results showed that TOH-containing emulgel at 1000 µM has excellent physical characteristics as homogenous, stability, and inhibits the growth of 30 species of human pathogenic fungi in vitro. TOH-containing emulgel did not cause skin irritation in mouse model of irritation and in healthy human volunteers. Moreover, an increase in skin hydration and a decrease in trans-epidermal water loss (TEWL) were observed after TOH-containing emulgel treatment on human skin. Our findings indicated that TOH-containing emulgel can be utilize as an antifungal agent for topical treatment against fungal infections on the skin.
Subject(s)
Indoles , Skin , Mice , Animals , Humans , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Administration, TopicalABSTRACT
The bacterial pathogen Burkholderia pseudomallei causes human melioidosis, which can infect the brain, leading to encephalitis and brain abscesses. Infection of the nervous system is a rare condition but is associated with an increased risk of mortality. Burkholderia intracellular motility A (BimA) was reported to play an important role in the invasion and infection of the central nervous system in a mouse model. Thus, to gain insight of the cellular mechanisms underlying the pathogenesis of neurological melioidosis, we explored the human neuronal proteomics to identify the host factors that are up- and downregulated during Burkholderia infection. When infected the SH-SY5Y cells with B. pseudomallei K96243 wild-type (WT), 194 host proteins showed a fold change of >2 compared with uninfected cells. Moreover, 123 proteins showed a fold change of >2 when infected with a knockout bimA mutant (ΔbimA) mutant compared with WT. The differentially expressed proteins were mainly associated with metabolic pathways and pathways linked to human diseases. Importantly, we observed the downregulation of proteins in the apoptosis and cytotoxicity pathway, and in vitro investigation with the ΔbimA mutant revealed the association of BimA with the induction of these pathways. Additionally, we disclosed that BimA was not required for invasion into the neuron cell line but was necessary for effective intracellular replication and multinucleated giant cell (MNGC) formation. These findings show the extraordinary capacity of B. pseudomallei in subverting and interfering with host cellular systems to establish infection and extend our understanding of B. pseudomallei BimA involvement in the pathogenesis of neurological melioidosis. IMPORTANCE Neurological melioidosis, caused by Burkholderia pseudomallei, can result in severe neurological damage and enhance the mortality rate of melioidosis patients. We investigate the involvement of the virulent factor BimA, which mediates actin-based motility, in the intracellular infection of neuroblastoma SH-SY5Y cells. Using proteomics-based analysis, we provide a list of host factors exploited by B. pseudomallei. The expression level of selected downregulated proteins in neuron cells infected with the ΔbimA mutant was determined by quantitative reverse transcription-PCR and was consistent with our proteomic data. The role of BimA in the apoptosis and cytotoxicity of SH-SY5Y cells infected by B. pseudomallei was uncovered in this study. Additionally, our research demonstrates that BimA is required for successful intracellular survival and cell fusion upon infection of neuron cells. Our findings have significant implications for understanding the pathogenesis of B. pseudomallei infections and developing novel therapeutic strategies to combat this deadly disease.
Subject(s)
Burkholderia pseudomallei , Burkholderia , Melioidosis , Neuroblastoma , Mice , Animals , Humans , Burkholderia/physiology , Melioidosis/microbiology , Proteomics , Burkholderia pseudomallei/genetics , Cell LineABSTRACT
Central nervous system (CNS) melioidosis caused by Burkholderia pseudomallei is being increasingly reported. Because of the high mortality associated with CNS melioidosis, understanding the underlying mechanism of B. pseudomallei pathogenesis in the CNS needs to be intensively investigated to develop better therapeutic strategies against this deadly disease. The type VI secretion system (T6SS) is a multiprotein machine that uses a spring-like mechanism to inject effectors into target cells to benefit the infection process. In this study, the role of the T6SS accessory protein TagAB-5 in B. pseudomallei pathogenicity was examined using the human microglial cell line HCM3, a unique resident immune cell of the CNS acting as a primary mediator of inflammation. We constructed B. pseudomallei tagAB-5 mutant and complementary strains by the markerless allele replacement method. The effects of tagAB-5 deletion on the pathogenicity of B. pseudomallei were studied by bacterial infection assays of HCM3 cells. Compared with the wild type, the tagAB-5 mutant exhibited defective pathogenic abilities in intracellular replication, multinucleated giant cell formation, and induction of cell damage. Additionally, infection by the tagAB-5 mutant elicited a decreased production of interleukin 8 (IL-8) in HCM3, suggesting that efficient pathogenicity of B. pseudomallei is required for IL-8 production in microglia. However, no significant differences in virulence in the Galleria mellonella model were observed between the tagAB-5 mutant and the wild type. Taken together, this study indicated that microglia might be an important intracellular niche for B. pseudomallei, particularly in CNS infection, and TagAB-5 confers B. pseudomallei pathogenicity in these cells.
ABSTRACT
Cryptococcosis in the central nervous system (CNS) can present with motor declines described as Parkinsonism. Although several lines of evidence indicate that dopaminergic (DA) neuron degeneration and α-synuclein accumulation contribute to the hallmark of Parkinsonism and Parkinson's disease (PD), little is known about cryptococcal infections associated with neuronal degeneration. In this study, the effects of Cryptococcus neoformans and C. gattii infections on dopaminergic neuron degeneration, α-synuclein accumulation, and lifespan in Caenorhabditis elegans were investigated. The results showed that cryptococcal infections significantly (P<0.05) induced DA neuron degeneration similar to a selective cathecholamine neurotoxin 6-hydroxydopamine (6-OHDA) in C. elegans (BZ555 strain) when compared to mock infected controls. Cryptococcal infections also significantly (P< 0.05) induced α-synuclein aggregation in C. elegans (NL5901 strain). Moreover, lifespan of the infected worms was significantly decreased (P<0.0001). In conclusion, DA neurodegeneration and α-synuclein accumulation are associated with lifespan reduction during cryptococcal infection in C elegans.
Subject(s)
Cryptococcus , alpha-Synuclein , Animals , alpha-Synuclein/pharmacology , Caenorhabditis elegans , Dopaminergic Neurons/pathology , Animals, Genetically Modified , Disease Models, Animal , Dopamine/pharmacology , Nerve Degeneration/pathologyABSTRACT
Background and purpose: Subcutaneous infections caused by Scedosporium apiospermum present as chronic eumycetomatous manifestations in both immunocompromised and immunocompetent individuals. Serious adverse effects/toxicities from the long-term use of antifungal drugs and antifungal resistance have been reported in patients with S. apiospermum infections. The present study aimed to determine the anti-S. apiospermum activities of fungal quorum sensing molecule known as tryptophol (TOH) and to develop a TOH-containing emulgel for treating S. apiospermum eumycetoma. Experimental approach: Anti-S. apiospermum activities of TOH were determined and compared with voriconazole. Effects of TOH on S. apiospermum biofilm formation and human foreskin fibroblast (HFF)-1 cell cytotoxicity were determined. Moreover, TOH-containing emulgel was developed and physical properties, in vitro, and in vivo antifungal activities against S. apiospermum eumycetoma were evaluated. Findings/Results: The minimal concentration of TOH at 100 µM exhibited anti-S. apiospermum activities by reducing growth rate, germination rate, and biofilm formation with less cytotoxicity to HFF-1 cells than voriconazole. Further study on the development of an emulgel revealed that TOH-containing emulgel exhibited excellent physical properties including homogeneity, consistency, and stability. Treatment by TOH-containing emulgel significantly reduced subcutaneous mass in a mouse model of S. apiospermum eumycetoma. The histopathological assessment showed marked improvement after 14 days of TOH-containing emulgel treatment. Conclusion and implications: TOH could be used as an anti-fungal agent against S. apiospermum infections. A novel and stable TOH-containing emulgel was developed with excellent anti-S. apiospermum activities suggesting the utilization of TOH-containing emulgel as an innovative therapeutic approach in the treatment of S. apiospermum eumycetoma.
ABSTRACT
PURPOSES: To evaluate inanimate surface contamination of SARS-CoV-2 during midfacial fracture repair (MFR) and to identify relevant aggregating factors. METHODS: Using a prospective non-randomised comparative study design, we enrolled a cohort of asymptomatic COVID-19 patients undergoing MFR. The predictor variables were osteofixation system (conventional titanium plates [CTiP] vs. ultrasound-assisted resorbable plates [USaRP]). The main outcomes were the presence of SARS-CoV-2 on four different surfaces. Other study variables were categorised into demographic, anatomical, and operative. Descriptive, bi- and multivariate statistics were computed. RESULTS: The sample consisted of 11 patients (27.3% females, 63.6% right side, 72.7% displaced fractures) with a mean age of 52.7 ± 20.1 years (range, 19-85). Viral spread was, on average, 1.9 ± 0.4 m. from the operative field, including most oral and orbital retractors' tips (81.8% and 72.7%) and no virus was found at 3 m from the operative field, but no significant difference was found between 2 osteofixation types. On binary adjustments, significantly broader contamination was linked to centrolateral MFR (P = 0.034; 95% confidence interval [CI], 0.05 to 1.02), and displaced MFR > 45 min (P = 0.022; 95% CI, 0.1 to 1.03). CONCLUSIONS: USaRP, albeit presumably heavily aerosol-producing, cause similar SARS-CoV-2 distribution to CTiP. Non-surgical operating room (OR) staff should stay ≥ 3 m from the operative field, if the patient is SARS-CoV-2-positive. Enoral and orbital instruments are a potential virus source, especially during displaced MFR > 45 min and/or centrolateral MFR, emphasising an importance of appropriate patient screening and OR organisation.
Subject(s)
COVID-19 , SARS-CoV-2 , Adult , Aged , COVID-19/epidemiology , Female , Humans , Male , Middle Aged , Prospective Studies , Respiratory Aerosols and Droplets , TitaniumABSTRACT
From 2018 to 2020, the Chikungunya virus (CHIKV) outbreak re-emerged in Thailand with a record of more than 10,000 cases up until the end of 2020. Here, we studied acute CHIKV-infected patients who had presented to the Bangkok Hospital for Tropical Diseases from 2019 to 2020 by assessing the relationship between viral load, clinical features, and serological profile. The results from our study showed that viral load was significantly high in patients with fever, headache, and arthritis. We also determined the neutralizing antibody titer in response to the viral load in patients, and our data support the evidence that an effective neutralizing antibody response against the virus is important for control of the viral load. Moreover, the phylogenetic analysis revealed that the CHIKV strains we studied belonged to the East, Central, and Southern African (ECSA) genotype, of the Indian ocean lineage (IOL), and possessed E1-K211E and E1-I317V mutations. Thus, this study provides insight for a better understanding of CHIKV pathogenesis in acute infection, along with the genomic diversity of the current CHIKV strains circulating in Thailand.
Subject(s)
Chikungunya Fever , Chikungunya virus , Antibodies, Neutralizing/genetics , Humans , Phylogeny , Thailand/epidemiologyABSTRACT
Burkholderia pseudomallei is a pathogenic bacterium that causes human melioidosis, which is associated with a high mortality rate. However, the underlying mechanisms of B. pseudomallei pathogenesis are largely unknown. In this study, we examined the infection of human neuronal SH-Sy5y cells by several clinically relevant B. pseudomallei strains. We found that all tested B. pseudomallei strains can invade SH-Sy5y cells, undergo intracellular replication, cause actin-tail formation, and form multinucleated giant cells. Additionally, a deletion mutant of B. pseudomallei cycle-inhibiting factor (cif) was constructed that exhibited reduced invasion in SH-Sy5y cells. Complementation of cif restored invasion of the B. pseudomallei cif-deleted mutant. Our findings enhance understanding of B. pseudomallei pathogenicity in terms of the virulence factor Cif and demonstrate the function of Cif in neurological melioidosis. This may eventually lead to the discovery of novel targets for treatment and a strategy to control the disease.
ABSTRACT
OBJECTIVE: To assess the correlation between oral lichen planus (OLP) and viral hepatitis C (HCV). METHODS: This retrospective case-control study included a sample of OLP patients in a 3-year interval. The predictor variable was the presence of OLP (yes/no). The outcome variable was the diagnosis of HCV. Other study variables were grouped into demographic, anatomic, and clinical. Descriptive, bi- and multivariate statistics were computed with a significant level at P ≤ 0.05. RESULTS: The sample was composed of 237 OLP patients (38.8% females) with a mean age of 59.9 ± 17.8 years (range, 17-96), and 948 age- and gender-matched control individuals. The significant higher frequency of HCV was identified in OLP patients (frequency: 19.8% vs. 2.1%; adjusted matched odds ratio [mORadj], 9.5; 95% confidence interval [95% CI], 5.98 to 15.91; P < 0.0001; Pearson's Phi coefficient [rphi], 0.307). In the adjusted model, OLP with HCV was associated with 1) oro-cutaneous manifestations (mORadj, 17.58; 95% CI, 1.92 to 161.26; Pâ¯=â¯0.0059; Bayesian posterior probability of positive test [Wp], 96%), 2) any intraoral forms other than reticular/plaque-liked forms (mORadj, 0.09; 95% CI, 0.04 to 0.18; P < 0.0001; Wp, 52%), and 3) poor response to topical corticosteroids (mORadj, 0.05; 95% CI, 0.02 to 0.16; P < 0.0001; Wp, 88%). CONCLUSIONS: OLP, especially oro-cutaneous disease or steroid-refractory OLP, are associated with an increased frequency of HCV. Not only HCV screening in OLP patients, but oral examination in HCV patients, are both recommended as primary preventive measures.
Subject(s)
Hepatitis C , Lichen Planus, Oral , Adult , Aged , Bayes Theorem , Case-Control Studies , Female , Hepacivirus , Hepatitis C/complications , Hepatitis C/diagnosis , Hepatitis C/epidemiology , Humans , Lichen Planus, Oral/complications , Lichen Planus, Oral/diagnosis , Lichen Planus, Oral/epidemiology , Male , Middle Aged , Retrospective StudiesABSTRACT
Burkholderia pseudomallei-a causative agent of melioidosis that is endemic in Southeast Asia and Northern Australia-is a Gram-negative bacterium transmitted to humans via inhalation, inoculation through skin abrasions, and ingestion. Melioidosis causes a range of clinical presentations including skin infection, pneumonia, and septicemia. Despite skin infection being one of the clinical symptoms of melioidosis, the pathogenesis of B. pseudomallei in skin fibroblasts has not yet been elucidated. In this study, we investigated B. pseudomallei pathogenesis in the HFF-1 human skin fibroblasts. On the basis of co-culture assays between different B. pseudomallei clinical strains and the HFF-1 human skin fibroblasts, we found that all B. pseudomallei strains have the ability to mediate invasion, intracellular replication, and multinucleated giant cell (MNGC) formation. Furthermore, all strains showed a significant increase in cytotoxicity in human fibroblasts, which coincides with the augmented expression of matrix metalloproteinase-2. Using B. pseudomallei mutants, we showed that the B. pseudomallei Bsa type III secretion system (T3SS) contributes to skin fibroblast pathogenesis, but O-polysaccharide, capsular polysaccharide, and short-chain dehydrogenase metabolism do not play a role in this process. Taken together, our findings reveal a probable connection for the Bsa T3SS in B. pseudomallei infection of skin fibroblasts, and this may be linked to the pathogenesis of cutaneous melioidosis.
Subject(s)
Burkholderia pseudomalleiABSTRACT
Exfoliative erythroderma is rare but serious condition, which requires close supervision. We report a rare case of 28-year-old man with kissing lesions of Paederus dermatitis at his right side of neck. The rash caused by Paederus beetle was improved after treatments. However, the patient developed generalized erythema with desquamation and scaling. The patient was successfully treated topically with moisturizing liquid soap and topical moisturizer with emollients and humectants, and triamcinolone lotion was applied on the bright red lesion. The patient was also treated with oral replacement solution and tropical azelaic cream was applied on the hyperpigmented kissing lesion. This case report shows the importance of a diagnostic practice with follow-up examination.