RSS 1.0Adult Critical Care
Recent Submissions
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Novel use of ultrasound-visible needle when performing thoracocentesis for low volume pleural effusionA letter to the Editor suggesting a novel use of ultrasound-visible needle when performing thoracocentesis for low volume pleural effusion.
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Birds of a feather : an uncommon cause of pneumonia and meningoencephalitisA 61-year-old man was admitted with a 1-week history of influenza-like symptoms during a period of increased influenza virus activity. He soon developed type 2 respiratory failure and became increasingly drowsy. He later suffered a convulsive episode in the intensive care unit (ICU) which self-terminated. Initial clinical findings suggested community-acquired pneumonia and meningoencephalitis. However, a detailed history revealed that he was a pet bird-keeper, which raised a suspicion of ornithosis. Chlamydia psittaci DNA was detected in sputum by PCR. He was started on appropriate antibiotics and made a full recovery. We present this uncommon cause of pneumonia as an example of the importance of accurate history-taking to ensure a correct diagnosis for optimal management.
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Intracellular and Tissue Levels of Vitamin B12 in Hepatocytes Are Modulated by CD320 Receptor and TCN2 TransporterThe liver mass constitutes hepatocytes expressing receptors for vitamin B12 (B12)-bound transporters in circulation. However, intrahepatic and circulating B12 interrelationship levels remain unclear. We assessed the intracellular B12 levels at various circulating B12 concentrations in human HepG2 cell-line and liver tissue levels of B12 in the C57BL/6 mouse model. In HepG2 cells treated with a range of B12 concentrations, the intracellular and circulatory B12 levels, transcript and protein levels of B12 receptor (CD320) and transporter (TCN2) were determined using immunoassays, qRT-PCR and Western blot, respectively. Similar assessments were done in plasma and liver tissue of C57BL/6 mice, previously fed a diet of either a high or low B12 (30.82 µg B12/kg and 7.49 µg B12/kg, respectively) for 8-10 weeks. The physiological B12 status (0.15-1 nM) resulted in increased levels of intracellular B12 in HepG2 cells compared to supraphysiological levels of B12 (>1 nM). Gene and protein expression of CD320 and TCN2 were also higher at physiological levels of B12. Progressively increasing extracellular B12 to supraphysiological levels led to relative decreased levels of intracellular B12, lower expression of gene and protein levels of CD320 and TCN2. Similar results were observed in liver tissue from mice fed on a low B12 diet verses high B12 diet. These findings suggest that unlike supraphysiological B12, physiological levels of B12 in the extracellular media or circulation accelerates active transport of B12, and expression of CD320 and TCN2, resulting in higher relative uptake of B12 in hepatocytes.