Primary and radiation induced skull base osteosarcoma: a systematic review of clinical features and treatment outcomes

Journal of Neuro-Oncology - We aim to systematically review and summarize the demographics, clinical features, management strategies, and clinical outcomes of primary and radiation-induced...     

Characterization of CTX-M and SHV extended-spectrum beta-lactamases and associated resistance genes in Escherichia coli strains of food samples in Tunisia

OBJECTIVES: To assess the occurrence of extended-spectrum beta-lactamases (ESBLs) in Escherichia coli isolates of faecal samples of animals (n = 40) and food samples (n = 38) obtained in Tunisia in 2006, and to characterize the type of ESBLs, their genetic environments and the associated resistance genes. METHODS: Samples were inoculated in supplemented media (2 mg/L cefotaxime) for isolation of broad-spectrum cephalosporin-resistant E. coli isolates (one isolate/sample). ESBLs and their genetic environments as well as integrons and their gene cassette composition were characterized by PCR and sequencing. RESULTS: ESBL-producing E. coli isolates were detected in 10 of the 38 food samples analysed (26%) and in none of the tested animal faecal samples. Genes found were as follows (number of isolates): bla(CTX-M-1) (5), bla(CTX-M-1) + bla(TEM-1b) (1), bla(CTX-M-14) + bla(TEM-1b) (2), bla(CTX-M-8) (1) and bla(SHV-5) (1). All ESBL-positive isolates showed unrelated PFGE patterns. ISEcp1 and IS903 were detected surrounding bla(CTX-M-14), and ISEcp1/IS26 and orf477 surrounding some of the bla(CTX-M-1) genes. Four of the ESBL-positive strains harboured class 1 integrons including different gene cassette combinations. CONCLUSIONS: ESBLs, mainly of the CTX-M class, are detected in E. coli of food origin in Tunisia, being the first time that this mechanism has been detected in food E. coli strains in Africa.     

Laparoscopy assisted transjejunal endoscopic retrograde cholangiography for treatment of intrahepatic duct stones in a post Roux-en-Y patient

We report a case of a 17-year-old female patient, who was operated on for choledocal cyst with Roux-en Y hepatojejunostomy. She was admitted to hospital with recurrent attacks of acute ascending cholangitis due to left intrahepatic duct stones. After a failed attempt at conventional endoscopic retrograde cholangiopancreatography through the anatomical route, she was treated successfully with laparoscopy assisted transjejunal endoscopic retrograde cholangiography.Endoscopic access to the biliary system can be difficult in patients with surgically altered anatomy of the upper gastrointestinal tract (GIT), such as Roux-en-Y reconstruction, because of the changed anatomy. However, endoscopic retrograde cholangiopancreatography (ERCP) is challenging in cases such as our patient;1,2 this is due to the distance needed to be traversed and looping. Our objective in presenting this particular case is to describe and highlight a laparoscopy assisted transjejunal ERCP to permit successful treatment and removal of intrahepatic duct stones in a post Roux-en-Y patient, and to minimize surgical inetervention to reduce unnecessary risks to the patient.     

A role for vesicular glutamate transporter 1 in synaptic vesicle clustering and mobility

Synaptic vesicles (SVs) from excitatory synapses carry vesicular glutamate transporters (VGLUTs) that fill the vesicles with neurotransmitter. Although the essential function of VGLUTs as glutamate transporters has been well established, the evidence for additional cell‐biological functions is more controversial. Both VGLUT1 and VGLUT2 disruptions in mice result in a reduced number of SVs away from release sites, flattening of SVs, and the appearance of tubular structures. Therefore, we analysed the morphology, biochemical composition and trafficking of SVs at synapses of VGLUT1^?/? mice in order to test for a function of VGLUTs in the formation or clustering of SVs. Analyses with high‐pressure freezing immobilisation and electron tomography pointed to a role of VGLUT1 transport function in the tonicity of excitatory SVs, explaining the aldehyde‐induced flattening of SVs observed in VGLUT1^?/? synapses. We confirmed the steep reduction in the number of SVs previously observed in VGLUT1^?/? presynaptic terminals, but did not observe accumulation of endocytotic intermediates. Furthermore, SV proteins of adult VGLUT1^?/? mouse brain tissue were expressed at normal levels in all subcellular fractions, suggesting that they were not displaced to another organelle. We thus assessed the mobility of the recently documented superpool of SVs. Synaptobrevin2–enhanced green fluorescent protein time lapse experiments revealed an oversized superpool of SVs in VGLUT1^?/? neurons. Our results support the idea that, beyond glutamate loading, VGLUT1 enhances the tonicity of excitatory SVs and stabilises SVs at presynaptic terminals.     

New-generation oral anticoagulants for the prevention of stroke: Implications for neurosurgery

A new generation of oral anticoagulants, namely direct thrombin inhibitors and factor X_a inhibitors, have recently been approved for clinical use in patients with atrial fibrillation. These novel families of drugs have been shown to have favorable efficacy and safety profiles in multiple clinical settings, particularly in the prevention of atrial fibrillation-related stroke, and are likely to become part of everyday practice, making a crossover to neurosurgical patients inevitable. Concern has risen regarding the complexity of managing intracranial and intraspinal hemorrhages related to these drugs. This review aims to provide an update on the most recent advances in oral anticoagulant drug therapy from a neurosurgeon’s perspective. We discuss current evidence for the use of these novel agents, their limitations, existing methods of drug-level monitoring, and controversies related to anticoagulation reversal. We also discuss specific topics such as anticoagulation resumption after intracranial or intraspinal bleeding, perioperative anticoagulant administration, and the possibility of combination with tissue plasminogen activator in the setting of acute ischemic stroke. A special focus is given to the incidence of intracranial and intraspinal hemorrhage associated with each drug.     

Incorporation of extruded coils into the third nerve in association with third nerve palsy

The extrusion of the coil complex outside of the aneurysmal dome is thought to be an important mechanism by which the aneurysm neck and fundus recanalize, but the migration of the coil loops and their incorporation inside vital nervous structures has not been clearly described. We reviewed the medical literature on coil extrusion and migration and report a rare case of third nerve palsy due to direct damage caused by coil loop migration that resolved after surgery. A 25-year-old woman presented with subarachnoid hemorrhage and painful left third nerve palsy. The angiogram revealed a supraclinoid internal carotid aneurysm incorporating the origin of the left posterior communicating artery. Her aneurysm was coiled. The 8 month follow-up angiogram revealed a major recurrence of her aneurysm. It was decided to surgically clip the aneurysm. At surgery, coil loops were found in the subarachnoid space and embedded into the third nerve. At 1 month follow-up she had recovered well, and only had very subtle diplopia upon fatigue. Coil extrusion is a fairly common phenomenon that should be suspected in instances of major aneurysmal recurrence. Surgical treatment is recommended, and special care should be taken when mobilizing the extruded coil mass.     

Kinetics of antibody and memory B cell responses after MMR immunization in children and young adults

The persistence of antigen-specific memory B-cells (MBCs) in children and young adults long time after vaccination against measles, mumps and rubella (MMR) is not known. Here we have looked at the Swedish immunization program and examined children 1–10 years after the first MMR dose in early childhood, as well as young adults 7–18 years after the second dose of MMR. We show that Ab titers and MBCs against measles and rubella have different kinetics, indicating that the MBC pool and the corresponding Ab titers are regulated independently. These data fit well with other findings that continuous IgG secretion comes from long-lived plasma cells and not MBCs. We also demonstrate that individuals with low post-vaccination Ab titers might have an adequate MBC response. It remains to be shown if memory B-cells provide the same protection as specific antibodies, but our data is a valuable complement to the incomplete knowledge about correlates of protection after vaccination.