“Artifactual fracture-subluxation” of cervical spine in computed tomography screening sans plain radiographs

Background contextComputed tomography (CT) has become the sole modality of screening for cervical injury in polytrauma because of the high sensitivity, speed, and convenience, thereby eliminating the need for plain radiographs.PurposeWe report two cases of misleading artifactual fracture-subluxation of cervical spine in CT, which could have resulted in needless treatment, and describe its characteristics.Study designCase report and review.MethodsTwo patients who were initially diagnosed with fracture-subluxation on screening CT cervical spine were later noted to have motion artifacts and were reviewed.ResultsThe artifactual nature of the supposed fracture-subluxation was unmasked by the soft-tissue findings of obscuration in sagittal reconstruction and duplication in axial images, along with the presence of double bony margins.ConclusionsMotion artifact in cervical CT screening can lead to a misdiagnosis of fracture subluxation. Duplication of soft tissue is highly suggestive of this motion artifact, and an additional single lateral plain radiograph may avert this pitfall.     

A rare presentation of hepatic and splenic cystic malignant fibrous histiocytoma: A case report and literature review

INTRODUCTIONMalignant fibrous histiocytoma is one of the most common soft tissue sarcomas in late adult life. But primary visceral malignant fibrous histiocytoma is a very rare entity. In peripheries, it is known to have an aggressive behavior but its biological pattern when involving liver and spleen is not well understood due to the rarity of its occurrence.PRESENTATION OF CASEA case of malignant fibrous histiocytoma of the liver and spleen as multiple cystic lesions in a 30 years old man is reported. The patient presented with hepatosplenomegaly resulting in central abdominal distention. Pre-operative investigations pointed toward the diagnosis of malignant cystic disease. The tumor presented as multiple hepatic cysts with massive hepatomegaly and splenomegaly. These cysts contained hemorrhagic fluid. Biopsy revealed highly cellular pleomorphic spindle cells fascicles arranged in storiform pattern at places with frequent mitoses. Immunohistochemistry revealed viamentin positivity. The tumor is compared with previous case reports.DISCUSSIONMalignant fibrous histiocytoma of liver and spleen has been mentioned in the literature as isolated case reports and most of these present as solid lesions but presentation as multiple cysts is also a possibility as was seen in this patient. It can be confirmed only on histo-pathology supported by immunohistochemistry. The disease carries guarded prognosis due to its rapid progression and diagnostic dilemma pre-operatively.CONCLUSIONThis rare malignancy affecting the viscera can be diagnosed only with high index of suspicion and awareness regarding its presentation can help surgeons deal with it.     

PET imaging of acetylcholinesterase inhibitor‐induced effects on α4β2 nicotinic acetylcholine receptor binding

Acetylcholinesterase inhibitors (AChEIs) are drugs that increase synaptic acetylcholine (ACh) concentrations and are under investigation as treatments for symptoms accompanying Alzheimer's disease. The goal of this work was to use PET imaging to evaluate alterations of in vivo α4β2 nicotinic acetylcholine receptor (nAChR) binding induced by the AChEIs physostigmine (PHY) and galanthamine (GAL). The α4β2 nAChR‐specific radioligand [¹⁸F]nifene was used to examine the effects of 0.1–0.2 mg/kg PHY, 5 mg/kg GAL, and saline in three separate experiments all performed on each of two rat subjects. A 60‐min bolus‐infusion protocol was used with drug administered after 30 min. Data from the thalamus and cortex were analyzed with a graphical model accounting for neurotransmitter activation using the cerebellum as a reference region to test for transient competition with bound [¹⁸F]nifene. Significant [¹⁸F]nifene displacement was detected in both regions during one PHY and both GAL studies, while no significant competition was observed in both saline studies. This preliminary work indicates the viability of [¹⁸F]nifene in detecting increases in synaptic ACh induced by AChEIs. Synapse 67:882–886, 2013. © 2013 Wiley Periodicals, Inc.     

Laccase production by the white-rot fungus Termitomyces clypeatus

Laccase was detected in the culture filtrate of white-rot fungus Termitomyces clypeatus. The enzyme was found at the late phase of submerged growth in a medium containing glucose or cellulose as the carbon source. The present study indicates that laccase produced by T. clypeatus is an intracellular enzyme, released in the medium due to cell lysis at the end of the growing phase. Laccase produced by T. clypeatus is different from the extracellular polyphenol oxidase of T. albuminosus, also produced at the late phase of growth. This is the first report of laccase production by a Termitomyces sp.     

Porin of Shigella dysenteriae activates mouse peritoneal macrophage through Toll-like receptors 2 and 6 to induce polarized type I response

Porin of Shigella dysenteriae type 1 coexpressed Toll-like receptor (TLR) 2 and TLR6 on peritoneal cavity (PerC) macrophages (MPhi) of C57BL/6 mice implicating that both the TLRs are essential as a combinatorial repertoire to recognize the protein. Besides TLRs, mRNA for MyD88 and TRAF6, and nuclear translocation of NF-kappaB were enhanced that indicate their involvement in tandem in the activity of porin. The protein selectively up-regulated CD80 on the activated MPhi together with MHC class II molecule and CD40, and had no effect on CD86 expression. The porin-induced profile of MIP-1alpha, MIP-1beta and RANTES showed strong bias for chemokines correlated with M1 polarization. Intracellular expression and release of TNF-alpha and IL-12 in presence of porin was found to be TLR2 and NF-kappaB dependent. Induction of TNF-alpha and IL-12 along with the chemokine profile suggests type I polarization of the MPhi that would influence Th1-type response.