Airway obstruction after extubation following use of transesophageal echocardiography for posterior fossa surgery in the sitting position.

We report respiratory obstruction following surgery in the sitting position with tracheal intubation and placement of a transesophageal echocardiography probe. Obstruction was due to pharyngeal oedema, which resolved with 24 hours. The mechanisms of this complication are discussed.     

Costello syndrome: Clinical phenotype,genotype, and management guidelines

Costello syndrome (CS) is a RASopathy caused by activating germline mutations in HRAS. Due to ubiquitous HRAS gene expression, CS affects multiple organ systems and individuals are predisposed to cancer. Individuals with CS may have distinctive craniofacial features, cardiac anomalies, growth and developmental delays, as well as dermatological, orthopedic, ocular, and neurological issues; however, considerable overlap with other RASopathies exists. Medical evaluation requires an understanding of the multifaceted phenotype. Subspecialists may have limited experience in caring for these individuals because of the rarity of CS. Furthermore, the phenotypic presentation may vary with the underlying genotype. These guidelines were developed by an interdisciplinary team of experts in order to encourage timely health care practices and provide medical management guidelines for the primary and specialty care provider, as well as for the families and affected individuals across their lifespan. These guidelines are based on expert opinion and do not represent evidence‐based guidelines due to the lack of data for this rare condition.     

Characterization of a complex translocation [t(4;9;22)(p16;q34;q11)] in chronic myelogenous leukemia by fluorescence in situ hybridization technique

A patient was referred with a high leukocyte count and diagnosed with chronic myelogenous leukemia (CML). Although practically asymptomatic since the time of diagnosis, he had a variable and inconsistent response to treatment. All of his bone marrow cells had a complex, three-way translocation, involving chromosomes 4, 9 and 22. Translocation of chromosome 4 to chromosome 9 was undetectable by routine cytogenetic techniques; however, by the fluorescence in situ hybridization technique, a three-way translocation was identified, 46,XYt(4;9;22)(p16;q34;q11). Although, other chromosomes are frequently involved in complex or variant translocations with chromosome 9 and 22, participation of chromosome 4 is a very rare event. So far, two previous cases have been described in the literature with translocations involving chromosome 4p16. We present a third case of CML having similar break points whose clinical presentation is unusual.     

Effect of lycoriside,an acylglucosyloxy alkaloid,on mast cells

The effect of lycoriside, an acylglucosyloxy alkaloid from Crinum asiaticum Linn, (family Amaryllidaceae), with or without sitosterol-3-O--D-glucoside, was studied on the rate of degranulation of peritoneal mast cells of albino rats. Lycoriside, at lower concentrations (1–20 µg/ml), in vitro, produced statistically significant protection against Tween 80-induced degranulation, as also to sensitized mast cells challenged with an antigen (horse serum). It also provided protection against compound 48/80-induced degranulation of mast cells when administered in vivo (1–5 mg/kg, po). At higher concentrations (100 µg/ml and above), in vitro, however, it had a mast-cell degranulation effect per se. The addition of sitosterol-3-O--D-glucoside to lycoriside did not modify the effect of the latter compound. The mechanism of the dual response elicited by lycoriside is appraised in view of a concentration-dependent anti- or prerelease effect on mast-cell mediators.     

Cuprizone [Bis(Cyclohexylidenehydrazide)] is Selectively Toxic for Mature Oligodendrocytes

Cuprizone [bis(cyclohexylidenehydrazide)]-induced toxic demyelination is an experimental animal model commonly used to study de- and remyelination in the central nervous system. In this model, mice are fed with the copper chelator cuprizone which leads to oligodendrocyte death with subsequent demyelination. The underlying mechanisms of cuprizone-induced oligodendrocyte death are still unknown, and appropriate in vitro investigations to study these mechanisms are not available. Thus, we studied cuprizone effects on rat primary glial cell cultures and on the neuroblastoma cell line SH-SY5Y. Treatment of cells with different concentrations of cuprizone failed to show effects on the proliferation and survival of SH-SY5Y cells, microglia, astrocytes, and oligodendrocyte precursor cells (OPC). In contrast, differentiated mature oligodendrocytes (OL) were found to be significantly affected by cuprizone treatment. This was accompanied by a reduced mitochondrial potential in cuprizone-treated OL. These results demonstrate that the main toxic target for cuprizone is mature OL, whilst other glial cells including OPC are not or only marginally affected. This explains the selective demyelination induced by cuprizone in vivo.     

Occlusion-amblyopia following high dose oral levodopa combined with part time patching

Part time occlusion therapy is not reported to cause occlusion (reverse) amblyopia. However, when combined with high dose oral levodopa, an increase in the plasticity of the visual cortex can lead to occlusion amblyopia. In this case report, we describe a six year old child who developed occlusion amblyopia following part time patching combined with oral levodopa.