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In Thailand, 408 campuses of the Buddhist Scripture School provide education to orphans, minorities, and disadvantaged children. Approximately 34,000 students are enrolled on the campuses nationwide. These students were ordained as novices and monks. In addition to studying their religious curriculum, they take courses in the general education, including English classes, and can obtain a high-school certificate. However, learning is disrupted regularly due to duties in the Buddhist communities, serving as the officiants of ceremonies, including merit making, funerals, weddings, etc., so their English achievement may not be satisfactory. This qualitative research investigated circumstances, challenges, and approaches to inclusive English education for novices and monks by adopting a critical pedagogy as the theoretical and analytical framework and a phenomenological approach as the methodological framework. The researcher visited a rural temple school to observe classes, inspect documents, and interview students, teachers, and abbots. The results show that most students resided in temples where people speak the Khmer dialect, and there were not enough opportunities to use English. The number of monks had decreased because of migration. Teachers had added responsibilities. Inclusive English education could be achieved by revitalizing the local economy and establishing a mentoring program to motivate them and inculcate student agency.

A new mononuclear copper(II) complex, [Cu(C7H5O3)(HCO2)(C10H9N3)], containing mixed N- and O-donor ligands, 2,2′-dipyridylamine (dpyam) and m-hydroxybenzoate (m-OHbenz), has been obtained from a solvent mixture. The coordination environment of the CuII ion is distorted square-pyramidal with a [N2O3] coordination set originating from the chelating dpyam and m-OHbenz ligands in the basal plane and the O atom of a formato ligand at the apical position. The crystal structure of the title complex is stabilized by N—H...O, O—H...O, C—H...O hydrogen-bonding, π–π and C—H...π intermolecular interactions, which were quantified by Hirshfeld surface analysis.

Identifying the movement of the branches of the hidden Thakhek fault in Thailand is challenging due to the absence of evident landforms indicating an active fault. In this study, we analyzed a digital elevation model (DEM) to identify potential landforms. A 2D Electrical Resistivity Tomography (ERT) survey was conducted to locate the hidden Thakhek fault. The results reveal vivid images of resistivity contrast, interpreted as two reverse faults, with mudstone exhibiting low resistivity in the middle, flanked by thick sediment layers with higher resistivity. Three trenches were excavated perpendicular to the two interpreted reverse faults. The displacement of reverse faulting appears to have shifted mudstone over Quaternary sediments, with vertical offsets revealed in trenches NWY-1, NWY-2, and NWY-3. This movement could be identified as a positive flower structure. Additionally, lakes are identified as a negative flower structure along the traces. These features result from strike-slip strains under a locally appropriate compressional and extensional environment in a shearing strike-slip fault.

Background: Prurigo nodularis (PN) is a chronic pruritic skin disease which can greatly impact patients’ quality of life. Moreover, the pathogenesis remains unclear, making it a difficult-to-treat condition. Aims: To investigate the expression of interleukin-31 (IL-31) in serum and skin biopsy specimens of PN patients and healthy subjects and identify its possible correlation to disease severity and itch intensity. Methods: Patients with PN and healthy volunteers were recruited for the study. Expression levels of IL-31 were measured by enzyme-linked immunosorbent assay and immunohistochemistry. Baseline characteristics, disease activity, itch intensity, and related laboratory results were collected. Results: Forty-three PN patients and 31 healthy subjects participated in our study. The PN patients had significantly higher mean serum IL-31 levels than the healthy subjects (52.9 ± 18.2 versus 36.3 ± 10.7 pg/ml, p

Drug resistance and metastasis are two major obstacles to cancer chemotherapy. During metastasis, cancer cells can survive as floating cells in the blood or lymphatic circulatory system, due to the acquisition of resistance to anoikis—a programmed cell death activated by loss of extracellular matrix attachment. The anoikis-resistant lung cancer cells also develop drug resistance. In this study, paclitaxel-encapsulated PLGA-lipid hybrid nanoparticles (PLHNPs) were formulated by nanoprecipitation combined with self-assembly. The paclitaxel-PLHNPs had an average particle size of 103.0 ± 1.6 nm and a zeta potential value of −52.9 mV with the monodisperse distribution. Cytotoxicity of the nanoparticles was evaluated in A549 human lung cancer cells cultivated as floating cells under non-adherent conditions, compared with A549 attached cells. The floating cells exhibited anoikis resistance as shown by a lack of caspase-3 activation, in contrast to floating normal epithelial cells. Paclitaxel tolerance was evident in floating cells which had an IC50 value of 418.56 nM, compared to an IC50 value of 7.88 nM for attached cells. Paclitaxel-PLHNPs significantly reduced the IC50 values in both attached cells (IC50 value of 0.11 nM, 71.6-fold decrease) and floating cells (IC50 value of 1.13 nM, 370.4-fold decrease). This report demonstrated the potential of PLHNPs to improve the efficacy of the chemotherapeutic drug paclitaxel, for eradicating anoikis-resistant lung cancer cells during metastasis.

Background: Chronic cavitary pulmonary disease and laryngeal involvement are unusual manifestations of Histoplasmosis capsulatum infection, particularly in patients who are not immunocompromised. The presence of fibro-cavitary lesions has been reported as a radiologic presentation of chronic histoplasmosis in patients with pre-existing lung disease. However, there have been few reports of extensive basal predominant cavitary lesions that mimic cystic-bronchiectasis. Case presentation: A 65-year-old previously healthy Thai male presented with productive cough, hoarseness, low-grade fever, and weight loss for 6 months. There was no history of significant exposure to Histoplasmosis capsulatum. Tests for HIV and anti–IFN–γ antibody were negative. Chest CT revealed multifocal thick wall cavities, which were distributed in a peri-bronchial pattern, and some areas of consolidation in both basal lungs. Laryngoscopy revealed an ulcerative lesion of the false vocal cords. Histopathological study of false vocal cords and lung tissue showed granulomatous inflammation with mixed inflammatory cell infiltration and aggregation of histiocytes containing round intracytoplasmic organisms. GMS-staining was positive, but negative mucicarmine-staining was negative. A real-time PCR assay of the lung tissue was positive for Histoplasmosis capsulatum. The final diagnosis was chronic cavitary pulmonary histoplasmosis with laryngeal involvement. Conclusion: Chronic cavitary pulmonary histoplasmosis is rare, as is laryngeal involvement. However, there have been such cases in endemic areas, even in immunocompetent patients. Chronic histoplasmosis should be considered in patients who present with the extensive basal predominant cavitary-pulmonary lesions that mimic cystic bronchiectasis.

Granulomatous polyangiitis (GPA) is a multiple systemic necrotizing vasculitis. Diagnosis of pulmonary nodules in GPA is still challenging in clinical practice, however, other extrapulmonary manifestations, serology, and histopathology may help the diagnosis of GPA. This case series was of limed GPA with one of the largest pulmonary nodules which had a poor treatment response in contrast with previous literature.

Multiple myeloma (MM) is a hematologic malignancy of plasma cell origin. Incidence of pleural effusion in multiple myeloma patients is approximately 6%. Myelomatous pleural effusions (MPE) are rare and occur in less than 1% of all MM cases. MPE is associated with advanced diseases, decreased survival time, and poor treatment response.In our case report, we describe a 59-year old man who presented with MPE at the initial diagnosis of MM. A diagnosis of MPE was reach through pleural fluid cytology and pleural tissue histology. The MPE had good response to initial dexamethasone without local therapy.

Rhinofacial entomophthoromycosis is an uncommon chronic fungal infection of the head and neck. The diagnosis is usually based on clinical manifestations; however, diagnosis of this infection based on early manifestations is difficult and occasionally rhinofacial entomophthoromycosis is mistaken for other diseases. Therefore, computed tomography is introduced to support the diagnosis. Radiologic findings were non-specific with swelling of the sinonasal mucosa and perinasal region. However, subcutaneous calcification, that was observed in all our cases, may be a supportive radiologic evidence for diagnosis. The diagnosis should be confirmed definitively using histopathology or fungal culture. Early diagnosis allows prompt and appropriate treatment that will achieve excellent outcomes.

For each triple of positive numbers p,q,r≥1 and each commutative C*-algebra ℬ with identity 1 and the set s(ℬ) of states on ℬ, the set 𝒮r(ℬ) of all matrices A=[ajk] over ℬ such that ϕ[A[r]]:=[ϕ(|ajk|r)] defines a bounded operator from ℓp to ℓq for all ϕ∈s(ℬ) is shown to be a Banach algebra under the Schur product operation, and the norm ‖A‖=‖|A|‖p,q,r=sup{‖ϕ[A[r]]‖1/r:ϕ∈s(ℬ)}. Schatten's theorems about the dual of the compact operators, the trace-class operators, and the decomposition of the dual of the algebra of all bounded operators on a Hilbert space are extended to the 𝒮r(ℬ) setting.

Winged bean (Psophocarpus tetragonolobus (L.) DC.) is a tropical legume crop found in Southeast Asian countries including Thailand. The mature seeds have high protein content and have been targeted as a protein source, and germination has been used to increase the value of nutrition. We used nanoLC/timsTOF Pro 2 combined with PEAKS® studio Xpro software to explore the proteomes of mature seeds and sprouts of purple winged bean. This study is the first report on the allergenic proteins in mature seeds and sprouts of purple winged bean. In silico analysis using Allergen Nomenclature search and the Allermatchtm program, 37 allergens were found. Conglutin beta 5 and late embryogenesis abundant protein (3 and D-29) were identified only in mature seeds, while 4 types of major pollen allergen Bet V, profilin and isoflavone reductase, were identified only in sprouts. Examples of allergens in both samples include basic 7S globulin, beta-conglycinin alpha/beta subunit (1,2), convicilin, defensin-like protein, 7 types of non-specific lipid-transfer protein, P24 oleosin isoform B. Since food allergy and airway allergy are found in sprouts, we used shotgun proteomics and in silico analysis for detecting the profiles of allergens. With regards to food safety, purple winged beans may also induce cross-reactivity in patients who are allergic to peanuts or other legumes. Therefore, identifying the proteomes and potential allergens in mature seeds and sprouts of purple winged beans could assist researchers in studying plant-based food safety. [Display omitted] • The first report of allergen detection in mature seeds and sprouts of purple winged bean. • In silico analysis revealed 37 allergens in mature seeds and sprouts of purple winged bean. • The detected food allergens were associated also with peanuts and other legumes. • Airway allergens were only found in sprouts of purple winged bean. [ABSTRACT FROM AUTHOR]

Let 𝒜 be a C*-algebra with identity 1, and let s(𝒜) denote the set of all states on 𝒜. For p,q,r∈[1,∞), denote by 𝒮r(𝒜) the set of all infinite matrices A=[ajk]j,k=1∞ over 𝒜 such that the matrix (ϕ[A[2]])[r]:=[(ϕ(ajk*ajk))r]j,k=1∞ defines a bounded linear operator from ℓp to ℓq for all ϕ∈s(𝒜). Then 𝒮r(𝒜) is a Banach algebra with the Schur product operation and norm ‖A‖=sup{‖(ϕ[A[2]])r‖1/(2r):ϕ∈s(𝒜)}. Analogs of Schatten's theorems on dualities among the compact operators, the trace-class operators, and all the bounded operators on a Hilbert space are proved.

Melioidosis is a life-threatening disease caused byBurkholderia pseudomallei. The lung is the most commonly affected organ, resulting in abscess formation in patients with chronic melioidosis. Previous study has shown thatB. pseudomalleiwas able to invade and multiply in epithelial cells. In the present study, we have demonstrated thatB. pseudomalleiis able to stimulate interleukin 8 (IL-8) production from the human alveolar lung epithelium cell line A549. However, the level of IL-8 production was significantly lower than when the cells were infected with other Gram-negative bacteria such asSalmonella entericaserovar Typhi (S. typhi) which were used for comparison. The degree of IκBα degradation in theB. pseudomallei-infected cells was lower than that of theS. typhi-infected cells, suggesting thatB. pseudomalleiis also a poorer cell activator. Inhibition ofB. pseudomalleiinvasion by cytochalasin D did not interfere with either IL-8 production or IκBα degradation, indicating that bacterial uptake is not required for the production of this chemokine. Thus, it appears that the signalling initiated by the interaction ofB. pseudomalleiwith the epithelial cell surface is sufficient for epithelial cell activation. [ABSTRACT FROM AUTHOR]

A sufficient condition for an infinite matrix having its norm as an operator on l² same as its Schur multiplier norm is given. All known examples, which have their operator norm same as Schur multiplier norm, satisfy this condition. Some related results are proved. A formula for the distance from a give matrix to the unitaries is also given. [ABSTRACT FROM AUTHOR]

Chronic cavitary pulmonary disease and laryngeal involvement are unusual manifestations of Histoplasmosis capsulatum infection, particularly in patients who are not immunocompromised. The presence of fibro-cavitary lesions has been reported as a radiologic presentation of chronic histoplasmosis in patients with pre-existing lung disease. However, there have been few reports of extensive basal predominant cavitary lesions that mimic cystic-bronchiectasis. A 65-year-old previously healthy Thai male presented with productive cough, hoarseness, low-grade fever, and weight loss for 6 months. There was no history of significant exposure to Histoplasmosis capsulatum. Tests for HIV and anti–IFN– γ antibody were negative. Chest CT revealed multifocal thick wall cavities, which were distributed in a peri-bronchial pattern, and some areas of consolidation in both basal lungs. Laryngoscopy revealed an ulcerative lesion of the false vocal cords. Histopathological study of false vocal cords and lung tissue showed granulomatous inflammation with mixed inflammatory cell infiltration and aggregation of histiocytes containing round intracytoplasmic organisms. GMS-staining was positive, but negative mucicarmine-staining was negative. A real-time PCR assay of the lung tissue was positive for Histoplasmosis capsulatum. The final diagnosis was chronic cavitary pulmonary histoplasmosis with laryngeal involvement. Chronic cavitary pulmonary histoplasmosis is rare, as is laryngeal involvement. However, there have been such cases in endemic areas, even in immunocompetent patients. Chronic histoplasmosis should be considered in patients who present with the extensive basal predominant cavitary-pulmonary lesions that mimic cystic bronchiectasis. [ABSTRACT FROM AUTHOR]

Granulomatous polyangiitis (GPA) is a multiple systemic necrotizing vasculitis. Diagnosis of pulmonary nodules in GPA is still challenging in clinical practice, however, other extrapulmonary manifestations, serology, and histopathology may help the diagnosis of GPA. This case series was of limed GPA with one of the largest pulmonary nodules which had a poor treatment response in contrast with previous literature. [ABSTRACT FROM AUTHOR]

Multiple myeloma (MM) is a hematologic malignancy of plasma cell origin. Incidence of pleural effusion in multiple myeloma patients is approximately 6%. Myelomatous pleural effusions (MPE) are rare and occur in less than 1% of all MM cases. MPE is associated with advanced diseases, decreased survival time, and poor treatment response. In our case report, we describe a 59-year old man who presented with MPE at the initial diagnosis of MM. A diagnosis of MPE was reach through pleural fluid cytology and pleural tissue histology. The MPE had good response to initial dexamethasone without local therapy. [ABSTRACT FROM AUTHOR]

Drug resistance and metastasis are two major obstacles to cancer chemotherapy. During metastasis, cancer cells can survive as floating cells in the blood or lymphatic circulatory system, due to the acquisition of resistance to anoikis-a programmed cell death activated by loss of extracellular matrix attachment. The anoikis-resistant lung cancer cells also develop drug resistance. In this study, paclitaxel-encapsulated PLGA-lipid hybrid nanoparticles (PLHNPs) were formulated by nanoprecipitation combined with self-assembly. The paclitaxel-PLHNPs had an average particle size of 103.0 ± 1.6 nm and a zeta potential value of -52.9 mV with the monodisperse distribution. Cytotoxicity of the nanoparticles was evaluated in A549 human lung cancer cells cultivated as floating cells under non-adherent conditions, compared with A549 attached cells. The floating cells exhibited anoikis resistance as shown by a lack of caspase-3 activation, in contrast to floating normal epithelial cells. Paclitaxel tolerance was evident in floating cells which had an IC 50 value of 418.56 nM, compared to an IC 50 value of 7.88 nM for attached cells. Paclitaxel-PLHNPs significantly reduced the IC 50 values in both attached cells (IC 50 value of 0.11 nM, 71.6-fold decrease) and floating cells (IC 50 value of 1.13 nM, 370.4-fold decrease). This report demonstrated the potential of PLHNPs to improve the efficacy of the chemotherapeutic drug paclitaxel, for eradicating anoikis-resistant lung cancer cells during metastasis.

Background/aim: Lung cancer is the leading cause of cancer death worldwide. Cigarette smoke is the most important risk factor for cancer development. Growing evidence indicates that prolonged nicotine exposure is a potential factor associated with tumorigenesis. Here, the effect of prolonged nicotine exposure on A549 cells was investigated, using label-free quantitative proteomics., Materials and Methods: Selection of an invasive subpopulation from the A549 cell line was performed to reveal the differential expression of proteins in relation to prolonged nicotine exposure, using Boyden chamber assays in combination with a proteomics approach., Results: One hundred proteins from the NicoA549-L5 subline showed significant change in expression compared to those from the A549-L5 subline and their A549 parental cell line. Heat shock protein, protein disulfide isomerase A3, profilin-1 and legumain were expressed at higher levels in A549 cells after prolonged nicotine exposure., Conclusion: These aberrant proteins might serve as novel cancer biomarkers for cigarette smokers., (Copyright © 2021 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Most Thai orchid farmers heavily used pesticide mixtures, and were shown to have various hematologic/immunologic alterations. The present study investigated the effect of exposure of male Wistar rats to a mixture of three pesticides (chlorpyrifos, cypermethrin and captan) that are most often used by the farmers. Three groups of 10 rats were dermally exposed to three different doses (high, middle and low) for 28 consecutive days. The rats showed significant changes in body, liver, kidneys and adrenals weights. Significant changes were observed in various biological parameters including hematotoxicity (increased leukocyte and platelet counts, percent neutrophil, decreased RBC count, percent lymphocyte and eosinophil), hepatotoxicity (increased serum AST, decreased serum ALP, cholesterol, triglyceride, serum protein and albumin), and immunotoxicity (decrease in numbers of NK cells, decrease splenic proliferative response to LPS, and increase in serum IgG). These results confirm the potential health danger of exposure to these pesticide mixtures in orchid farmers., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Antivenomics is a recently developed powerful method for the study of antivenom antibody profiles when bound to homologous and heterologous snake venoms. The information obtained is useful in gaining an understanding of venom protein immunogenicity, antivenom potency and also for the improvement of antivenom potency and paraspecificity. The preferred method used in this type of study is immunoaffinity chromatography of the venom proteins on an antivenom IgG (or F(ab')2) column where the bound and unbound proteins can be separated and identified. However, there are some parameters of the immunochromatography that can significantly affect the binding of the proteins to the immunoaffinity matrix and lead to imprecise results in antivenom immunoprofiling. The present study demonstrated that the ligand density (mg IgG/ml of the matrix), the buffers used for binding and washing the venom proteins, the amount of venom loaded, the abundance of some venom protein(s) and the eluting buffers can significantly alter the binding of the proteins to the matrix and consequently the conclusions drawn from antivenomics studies. Furthermore, the immunochromatographic procedure can be extended to include the estimation of the relative affinity of venom protein-antibody interactions that can provide additional information useful to antivenomics study., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Pythiosis is a life-threatening infectious disease of both humans and animals living in Asia, Americas, Africa, and parts of Australia and New Zealand. The etiologic pathogen is the fungus-like organism Pythium insidiosum The disease has high mortality and morbidity rates. Use of antifungal drugs are ineffective against P. insidiosum, leaving radical surgery the main treatment option. Prompt treatment leads to better prognosis of affected individuals, and could be achieved by early and accurate diagnosis. Since pythiosis has been increasingly reported worldwide, there is a need for a rapid, user-friendly, and efficient test that facilitates the diagnosis of the disease. This study aims to develop an immunochromatographic test (ICT), using the bacterial protein A/G, to detect anti-P. insidiosum IgGs in humans and animals, and compare its diagnostic performance with the established ELISA. Eighty-five serum samples from 28 patients, 24 dogs, 12 horses, 12 rabbits, and 9 cattle with pythiosis, and 143 serum samples from 80 human and 63 animal subjects in a healthy condition, with thalassemia, or with other fungal infections, were recruited for assay evaluation. Detection specificities of ELISA and ICT were 100.0%. While the detection sensitivity of ELISA was 98.8%, that of ICT was 90.6%. Most pythiosis sera, that were falsely read negative by ICT, were weakly positive by ELISA. In conclusion, a protein A/G-based ICT is a rapid, user-friendly, and efficient assay for serodiagnosis of pythiosis in humans and animals. Compared to ELISA, ICT has an equivalent detection specificity and a slightly lower detection sensitivity., (© The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Naja naja (Indian cobra) from Sri Lanka and India is the WHO Category 1 medically important snakes in both countries. Some antivenom produced against Indian N. naja (NNi) were less effective against Sri Lankan N. naja (NNsl). Proteomes of NNi and NNsl venoms were studied by RP-HPLC, SDS-PAGE and LC/MS/MS. Six protein families were identified in both venoms with the most abundant were the 3 finger toxins (3FTs) where cytotoxins (CTX) subtype predominated, followed by phospholipase A2, cysteine-rich venom protein, snake venom metalloproteases, venom growth factors, and protease inhibitors. Qualitative and quantitative differences in the venomics profiles were observed. Some proteins were isolated from either NNi or NNsl venom. Postsynaptic neurotoxins (NTX) were identified for the first time in NNsl venom. Thus, there are geographic intra-specific variations of venom composition of the two N. naja. The relative abundance of CTX and NTX explained well the clinical manifestations of these venoms. Antivenomics study of an Indian antivenom (Vins) showed the antibodies effectively bound all venom toxins from both snakes but more avidly to the Indian venom proteins. The lower antibody affinity towards the 'heterologous' venom was the likely cause of poor efficacy of the Indian antivenom used to treat NNsl envenoming., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Various studies have found that many Thai orchid farmers used excessive amounts of pesticides without proper protective gear, but no toxicological study has been made. This cross-sectional study aimed to evaluate the immunological, hematological and biochemical statuses of these farmers. Sixty four orchid farmers and 60 controls were studied. Plasma cholinesterase activity, the percentage and absolute number of B lymphocytes (CD19+) were significantly lower in the farmers group (3966.32±1165.48 U/L, 11.61±4.09% and 312.26±164.83 cells/mm3, respectively) as compared to those of controls (5048.85±1139.40 U/L, 14.32±4.23%, 420.34±195.18 cells/mm3, respectively). There was a statistically significant higher level of serum IgE among the orchid farmers (0.031±0.011 mg/dL vs. 0.018±0.007 mg/dL) but not IgG, IgA and IgM, levels. Serum lysozyme level, lymphocyte proliferative responses to mitogens, hematological parameters and kidney function test, were not significantly different between the two groups. The liver function profiles showed significantly lower levels of albumin and serum protein in the farmer group. Thus frequent pesticide exposure resulted in subtle changes of some biological parameters. These changes, though may not be clinically significant, strongly indicated that caution in handing pesticides by these farmers is warranted.

Background: A progressive reduction in peritubular capillary flow is observed in chronic kidney disease (CKD) patients as the disease severity progresses. This suggests an altered vascular homeostasis in CKD patients, but such a defective mechanism needs to be verified., Methods: To study the vascular injury as reflected by circulating endothelial cell (CEC), the balance between angiogenic factor, vascular endothelial growth factor (VEGF), and antiangiogenic factor, endostatin., Results: A deficient VEGF was observed, whereas the value of endostatin and CEC were abnormally elevated in CKD patients., Discussion: Enhanced CEC reflects an increased activity of vascular injury. A deficient VEGF in the presence of enhanced antiangiogenesis (endostatin) implies a defective angiogenesis. This may explain the progressive nature of renal microvascular disease observed in late stage of CKD patients.

Burkholderia pseudomallei is a causative agent of melioidosis. This Gram-negative bacterium is able to survive and multiple inside both phagocytic and nonphagocytic cells. We previously reported that exogenous interferons (both type I and type II) enhanced antimicrobial activity of the macrophages infected with B. pseudomallei by up-regulating inducible nitric oxide synthase (iNOS). This enzyme thus plays an essential role in controlling intracellular growth of bacteria. In the present study we extended our investigation, analysing the mechanism(s) by which the two types of interferons (IFNs) regulate antimicrobial activity in the B. pseudomallei-infected macrophages. Mouse macrophage cell line (RAW 264.7) that was exposed simultaneously to B. pseudomallei and type I IFN (IFN-beta) expressed high levels of iNOS, leading to enhanced intracellular killing of the bacteria. However, neither enhanced iNOS expression nor intracellular bacterial killing was observed when the macrophages were preactivated with IFN-beta prior to being infected with B. pseudomallei. On the contrary, the timing of exposure was not critical for the type II IFN (IFN-gamma) because when the cells were either prestimulated or co-stimulated with IFN-gamma, both iNOS expression and intracellular killing capacity were enhanced. The differences by which these two IFNs regulate antimicrobial activity may be related to the fact that IFN-gamma was able to induce more sustained interferon regulatory factor-1 (IRF-1) expression compared with the cells activated with IFN-beta.

Burkholderia pseudomallei is a causative agent of melioidosis, a life threatening disease which affects humans and animals in tropical and subtropical areas. This bacterium is known to survive and multiply inside cells such as macrophages. The mechanism of host defense against this bacterium is still unknown. In this study, we demonstrated that B. pseudomallei exhibited unique macrophage activation activity compared with Escherichia coli and Salmonella typhi. The mouse macrophage cell line (RAW 264.7) infected with B. pseudomallei at MOI of 0.1:1, 1:1 and 10:1 did not express a detectable level of inducible nitric oxide synthase (iNOS). Moreover, the B. pseudomallei infected cells released TNF-alpha only when they were infected with high MOI (10:1). Unlike the cells infected with B. pseudomallei, the cells infected with E. coli, and S. typhi expressed iNOS even at MOI of 0.1:1. These infected cells also released a significantly higher level of TNF-alpha at the low MOI ratio. The cells that were preactivated with IFN-gamma prior to being infected with B. pseudomallei exhibited an enhanced production of iNOS and TNF-alpha release. The increased macrophage activation activity in the presence of IFN-gamma also correlated with the restriction of the intracellular bacteria survival. Moreover, IFN-gamma also prevented cell fusion and multinucleated cell formation induced by B. pseudomallei, a phenomenon recently described by our group. Altogether, these results indicate that internalization of B. pseudomallei failed to trigger substantial macrophage activation, a phenomenon which could prolong their survival inside the phagocytic cells and facilitate a direct cell to cell spreading of B. pseudomallei to neighboring cells.