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Background: Animal models with various combination of host-parasite have long been employed to study malaria pathogenesis. Here, we describe the combination of Plasmodium berghei ANKA infection in inbred ICR mice as a model of cerebral malaria (CM). Methods: Infection in mice was initiated by intraperitoneal injection of 2 x 107 (0.2ml) parasitized red blood cells (PRBCs). Results: This model can produce a severe degree of infection presented by the high degree of parasitaemia followed by death 6-7 days post infection. Severe anemia, splenomegaly, hepatomegaly and discolourations of major organs were observed. Histopathological findings revealed several important features mimicking human CM including, microvascular sequestration of PRBCs in major organs, particularly in the brain, hypertrophy and hyperplasia of the kupffer cells in the liver, pulmonary edema and hyaline membrane formation in the lungs and haemorrhages in the kidney's medulla and cortex. Proinflammatory cytokines TNFα, IFNγ, IL-1, IL-6 and IL-18, and anti-inflammatory cytokine IL-10 were all found to be elevated in the plasma of infected mice. Conclusion: This model can reproduce many of the important features of CM and therefore can be used as a tool to advance our understanding of the disease pathogenesis. [ABSTRACT FROM AUTHOR]

Acute administration of high-dose testosterone in men with coronary artery disease improves endothelial function. [ABSTRACT FROM AUTHOR]

Interleukin-27 (IL-27) has a pleiotropic role either as a pro-inflammatory or anti-inflammatory cytokine in inflammatory related diseases. The role and involvement of IL-27 during malaria was investigated and the effects of modulating its release on the production of major inflammatory cytokines and the histopathological consequences in major affected organs during the infection were evaluated. Results showed that IL-27 concentration was significantly elevated throughout the infection but no positive correlation with the parasitaemia development observed. Augmentation of IL-27 significantly elevated the release of anti-inflammatory cytokine, IL-10 whereas antagonising and neutralising IL-27 produced the opposite. A significant elevation of pro-inflammatory cytokines (IFN-γ and IL-6) was also observed, both during augmentation and inhibition of IL-27. Thus, it is suggested that IL-27 exerts an anti-inflammatory activity in the Th1 type response by signalling the production of IL-10 during malaria. Histopathological examination showed sequestration of PRBC in the microvasculature of major organs in malarial mice. Other significant histopathological changes include hyperplasia and hypertrophy of the Kupffer cells in the liver, hyaline membrane formation in lung tissue, enlargement of the white and red pulp followed by the disappearance of germinal centre of the spleen, and tubular vacuolation of the kidney tissues. In conclusion, it is suggested that IL-27 may possibly acts as an anti-inflammatory cytokine during the infection. Modulation of its release produced a positive impact on inflammatory cytokine production during the infection, suggesting its potential in malaria immunotherapy, in which the host may benefit from its inhibition.

Introduction: On 22 March 2003, the Ministry of Health, Singapore, designated Tan Tock Seng Hospital as the nationwide severe acute respiratory syndrome (SARS) hospital and its Emergency Department (ED) took over the role as the screening center for SARS on 26 March 2003. We describe the initial clinical characteristics of probable or suspect SARS patients that presented to the ED., Methods: A retrospective study of patients who were admitted through the ED and subsequently diagnosed to have probable SARS and suspect SARS was done. The data of these patients from the ED log were reviewed and analysed., Results: From 13 March 2003 to 31 May 2003, 11,461 patients were screened for SARS and 1,386 patients were admitted. Of these, 117 patients were diagnosed to have probable SARS and 146 suspect SARS. Their mean age was 36.7 years (range 1-80). Among these patients, there were 122 men (46.4 percent), and 205 were Singaporeans (77.9 percent). 13 patients had no initial contact history upon presentation to the ED. The mean duration between onset of symptom to presentation to the ED was 3.1 days. Travel history was less common in probable SARS cases than in suspect SARS cases as the epidemic was due mainly to local transmission. Fever was the most common presenting symptom (91.6 percent), and gastrointestinal symptoms were the least (6.9 percent). In the ED, 249 (94.7 percent) patients had chest radiographs and 86 (32.7 percent) had full blood count done. 22.2 percent of probable SARS patients had normal chest radiographs when they first presented to the ED., Conclusion: The World Health Organisation criteria were important screening tools and admission guides, but should not be strictly followed. It was difficult to differentiate between probable and suspect SARS patients in the ED.