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Publication Open Access Retinal changes in visceral leishmaniasis by retinal photography(2014) Maude, Richard James; Ahmed, BUM Wahid; Abu Hayat Md Waliur Rahman; Rahman, Ridwanur; Majumder, Mohammed Ishaque; Menezes, Darryl Braganza; Sayeed, Abdullah Abu; Hughes, Laura; MacGillivray, Thomas J; Borooah, Shyamanga; Dhillon, Baljean; Dondorp, Arjen M; Faiz, Mohammad Abul; Mahidol University. Faculty of Tropical Medicine. Mahidol-Oxford Tropical Medicine Research Unitassessed by masked observers including assessment for vessel tortuosity using a semi-automated system. Results: 30 patients with VL were enrolled, of whom 6 (20%) had abnormalities. These included 5 with focal retinal whitening, 2 with cotton wool spots..., 2 with haemorrhages, as well as increased vessel tortuosity. Visual function was preserved. Conclusions: These changes suggest a previously unrecognized retinal vasculopathy. An inflammatory aetiology is plausible such as a subclinical retinalPublication Open Access Improved R2* liver iron concentration assessment using a novel fuzzy c-mean clustering scheme(2015) Pairash Saiviroonporn; Vip Viprakasit; Rungroj Krittayaphong; Mahidol University. Faculty of Medicine Siriraj Hospital. Division of Diagnostic RadiologyLIC measurement, existing methods suffer from LIC variability, especially at the severe iron overload range due to inclusion of vessel parts in LIC calculation. In this study, we build upon previous Fuzzy C-Mean (FCM) clustering work to formulate a... scheme with superior performance in segmenting vessel pixels from the parenchyma. Our method (MIX-FCM) combines our novel 2D-FCM with the existing 1D-FCM algorithm. This study further assessed possible optimal clustering parameters (OP schemePublication Open Access Coma in fatal adult human malaria is not caused by cerebral oedema(2011-09-17) Medana, Isabelle M.; Day, Nicholas P.J.; Navakanit Sachanonta; นวขนิษฐ์ สัจจานนท์; Mai, Nguyen T.H.; Dondorp, Arjen M.; Emsri Pongponratn; เอี่ยมศรี พงศ์พนรัตน์; Hien, Tran T.; White, Nicholas J.; Turner, Gareth D.H.; Turner, Gareth D.H.; Mahidol University. Faculty of Tropical Medicine. Mahidol-Oxford Research Unit.; Mahidol University. Faculty of Tropical Medicine. Department of Tropical Pathology.sequestration and resultant microvascular congestion in cerebral vessels. To determine whether these changes cause breakdown of the blood-brain barrier and resultant perivascular or parenchymal cerebral oedema, histology, immunohistochemistry and image analysisPublication Open Access A clinicopathological correlation of the expression of the angiopoietin-Tie-2 receptor pathway in the brain of adults with Plasmodium falciparum malaria(2013) Panote Prapansilp; Isabelle Medana; Nguyen Thi Hoan Mai; Day, Nicholas PJ; Phu, Nguyen Hoan; Yeo, Tsin W; Hien, Tran Tinh; Nicholas J White; Anstey, Nicholas M; Turner, Gareth DH; Mahidol University. Faculty of Tropical Medicine. Mahidol-Oxford Tropical Medicine Research UnitBackground: Plasma angiopoietin (Ang)-2 is associated with disease severity and mortality in adults and children with falciparum malaria. However the mechanism of action of the angiopoietins in fatal malaria is unclear. This study aimed to determine whether the expression of Ang-1 and Ang-2 and their receptor Tie-2 in cerebral endothelial or parenchymal cells was specific to cerebral malaria (CM), correlated with coma or other severe clinical features, and whether plasma and CSF levels of these markers correlated with the clinical and neuropathological features of severe and fatal malaria in Vietnamese adults. Methods: Immunohistochemistry was performed for Ang-1, Ang-2 and Tie-2 on post-mortem brain tissue from fatal malaria cases and controls. Quantitative ELISA for plasma and cerebrospinal fluid levels of Ang-1, Ang-2 and Tie-2 was done to compare fatal cases with surviving patients from the same study. Results: Immunohistochemistry revealed significant differences in expression in endothelial and parenchymal cells compared to controls. However there was no significant difference in expression of these markers on endothelial cells, astroglial cells or neurons between CM and non-cerebral malaria cases. Immunostaining of Ang-1, Ang-2 and Tie-2 was also not associated with Plasmodium falciparum-infected erythrocyte sequestration in the brain. However Ang-1 and Ang-2 expression in neurons was significantly correlated with the incidence of microscopic haemorrhages. Plasma levels of Ang-2 and Ang-2/Ang-1 ratio were associated with the number of severe malaria complications and were significant and independent predictors of metabolic acidosis and fatal outcome. Conclusions: The independent prognostic significance of Ang-2 and the Ang-2/Ang-1 ratio in severe malaria was confirmed, although immunohistochemistry in fatal cases did not reveal increased expression on brain endothelium in cerebral versus non-cerebral cases. Activation of the Ang-Tie-2 pathway in severe malaria is therefore related to acidosis, number of severity criteria and outcome, but is not a specific event in the brain during cerebral malaria.Publication Open Access Mast cell activation in the skin of Plasmodium falciparum malaria patients.(2015-02-07) Panop Wilainam; ภานพ วิไลนาม; Rungrat Nintasen; Parnpen Viriyavejakul; พรรณเพ็ญ วิริยเวชกุล; Parnpen Viriyavejakul; Mahidol University. Faculty of Tropical Medicine. Department of Tropical Pathology.; Mahidol University. Faculty of Veterinary Science. Department of Preclinic and Applied Animal Science.BACKGROUND: Mast cells (MCs) play an important role in the immune response and inflammatory processes. Generally, MCs can be stimulated to degranulate and release histamine upon binding to immunoglobulin E (IgE). In malaria, MCs have been linked to immunoglobulin (Ig) E-anti-malarial antibodies. This study investigated the response of MCs in the skin of patients with Plasmodium falciparum malaria. METHODS: Skin tissue samples were examined from ten uncomplicated and 20 complicated P. falciparum malaria cases. Normal skin tissues from 29 cases served as controls. Pre- and post-treatment tissues were included. Histopathological changes of the skin were evaluated using haematoxylin and eosin stain. MCs were investigated using toluidine blue staining. The percentage of MC degranulation was compared among groups and correlated with clinical data. RESULTS: MC degranulation was significantly higher in the complicated P. falciparum (43.72% ± 1.44) group than the uncomplicated P. falciparum (31.35% ± 3.29) (p <0.05) and control groups (18.38% ± 1.75), (p <0.0001). MC degranulation correlated significantly with the degree of parasitaemia (r s = 0.66, p <0.0001). Associated pathological features, including extravasation of red blood cells, perivascular oedema and leukocyte infiltration were significantly increased in the malaria groups compared with the control group (all p <0.001). CONCLUSIONS: MCs in the skin dermis are activated during malaria infection, and the degree of MC degranulation correlates with parasitaemia and disease severity.Publication Open Access Nuclear factor kappa B modulates apoptosis in the brain endothelial cells and intravascular leukocytes of fatal cerebral malaria(2013) Chuchard Punsawad; Yaowapa Maneerat; Urai Chaisri; Kwannan Nantavisai; Parnpen Viriyavejakul; Mahidol University. Faculty of Tropical Medicine. Department of Tropical PathologyBackground: Cerebral malaria (CM) caused by Plasmodium falciparum is known to be associated with the sequestration of parasitized red blood cells (PRBCs) in the microvasculature and the release of soluble cytokines. In addition, the involvement of signaling molecules has gained wide interest in the pathogenesis of CM. An important signaling factor, nuclear factor kappa B (NF-κB) is known to regulate apoptosis. This work aimed to study the expression of NF-κB p65 and its correlation with apoptosis in the brain of fatal CM. Methods: The expression of NF-κB p65 and cleaved caspase-3 in the brain of fatal P. falciparum malaria cases was investigated by immunohistochemistry. Histopathological features were analysed together with the correlations of NF-κB p65 and cleaved caspase-3 expression. Results: NF-κB p65 activation and cleaved caspase-3 expression were significantly increased in the neurons, glial cells, vascular endothelial cells (ECs) and intravascular leukocytes of the brain in fatal CM, compared with the control brain (p < 0.001) and non-cerebral malaria (NCM) (p = 0.034). The percentage of neurons that expressed nuclear NF-κB p65 showed a positive correlation with the total score of histopathological changes (rs = 0.678; p = 0.045). Significant positive correlations were established between vascular ECs NF-κB index and ECs apoptotic index (rs = 0.717; p = 0.030) and between intravascular leukocytes NF-κB index and leukocytes apoptotic index (rs = 0.696; p = 0.037) in fatal CM. Conclusions: This study documented that NF-κB p65 is one of the signaling factors that modulates apoptosis in the brain ECs and intravascular leukocytes of fatal CM.Publication Open Access Morphological changes and infiltration of immune cells in the endometrium of anoestrus gilt in relation to the ovarian appearance and serum progesterone.(2010) Yuttapol Teamsuwan; Kampon Kaeoket; Paisan Tienthai; Padet Tummaruk; Mahidol University. Faculty of Veterinary Scienceserum P4. Seven tissue samples were randomly collected from the uteri of the gilts and were examined for histological structures, i.e. epithelial types and height, number of blood vessel, secretory vesicle and endometrial glands. Number of leukocytePublication Open Access Psychophysiological changes of cigarette smokers to stimuli of aerobic and anaerobic exercises(2012-07) Thyon Chentanez; Yaowalak Anothayanont; Panya Kimuk; Tossaporn Yimlamai; Mahidol University. College of Sports Science and Technology; Mahidol University. Faculty of Science, smoking was associated with reduction in physical performance, psycho-neurological performance and vasomotor responses. This may explain smoking related atherosclerotic changes of blood vessels in the brain and organs and the severity may dependPublication Open Access Nitric Oxide Protects against Infection-Induced Neuroinflammation by Preserving the Stability of the Blood-Brain Barrier(2016-02) Gabriela C. Olivera; Xiaoyuan Ren; Suman K. Vodnala; Jun Lu; Lucia Coppo; Chaniya Leepiyasakulchai; Arne Holmgren; Krister Kristensson; Martin E. Rottenberg; Mahidol University. Faculty of Medical Technology. Department of Clinical Microbiology and Applied TechnologyTrypanosoma brucei parasites were compared in inos-/- and wild-type mice. Inos-/- mice showed enhanced brain invasion by parasites and T cells, and elevated protein permeability of cerebral vessels, but similar parasitemia levels. Trypanosome infection... parasite brain invasion. In inos-/- mice, TNF stimulated MMP, including MMP9 activity that increased cerebral vessel permeability. Thus, iNOS-generated NO by perivascular macrophages, strategically located at sites of leukocyte brain penetration, can servePublication Open Access Endothelial Progenitor Cell Migration-Enhancing Factors in the Secretome of Placental-Derived Mesenchymal Stem Cells(2016) Witchayaporn Kamprom; Pakpoom Kheolamai; Yaowalak U-Pratya; Aungkura Supokawej; Methichit Wattanapanitch; Chuti Laowtammathron; Sittiruk Roytrakul; Surapol Issaragrisil; Mahidol University. Faculty of Medical Technology. Department of Clinical MicroscopyTherapeutic potentials of mesenchymal stem cells (MSCs) depend largely on their ability to secrete cytokines or factors that modulate immune response, enhance cell survival, and induce neovascularization in the target tissues. We studied the secretome profile of gestational tissue-derived MSCs and their effects on functions of endothelial progenitor cells (EPCs), another angiogenic cell type that plays an important role during the neovascularization. MSCs derived from placental tissues (PL-MSCs) significantly enhanced EPC migration while BM-MSCs, which are the standard source of MSCs for various clinical applications, did not. By using protein fractionation and mass spectrometry analysis, we identified several novel candidates for EPC migration enhancing factor in PL-MSCs secretome that could be used to enhance neovascularization in the injured/ischemic tissues. We recommend that the strategy developed in our study could be used to systematically identify therapeutically useful molecules in the secretomes of other MSC sources for the clinical applications.