Mechanical complications of long-term Tesio catheters.

Vascular access catheters such as Tesio-Caths are preferentially inserted in the internal jugular vein and serve as access for hemodialysis. Complications related to the removal of these types of lines are uncommon. We report four patients in whom the tip of the Tesio-Cath broke and was left stuck in the superior vena cava. Although there is no defined limit to the maximum length of stay of vascular access catheters for dialysis, the possibility of catheter entrapment should be considered. It remains to be determined whether removing Tesio-Caths every 16- 18 months is beneficial in avoiding this complication.

Ventral neurogenesis and the neuron-glial switch.

In the developing spinal cord, neuroepithelial precursors at different positions along the dorsal-ventral axis generate distinct neuronal and glial subtypes. For example, one group of ventral precursors generates neurons followed by oligodendrocytes. A spate of recent articles, including several in this issue of Neuron, are devoted to the mechanisms governing neuronal and glial subtype specification in the ventral cord. We review these studies and discuss the nature of the ventral neuron-oligodendrocyte switch.

Characterisation, chromosomal localisation and expression of the mouse Kid3 gene.

Kid1 encodes a transcriptional repressor implicated in the differentiation of renal epithelial cells. Here we report the characterisation of Kid3, a novel mouse gene related to Kid1. Kid3 encodes a C2H2 zinc finger protein with an N-terminal KRAB transcriptional repression domain. It maps to chromosome 11, adjacent to Kid1 and another related gene Kid2. Northern analysis shows that Kid3 is highly expressed in embryonic and adult brain, with lower levels in adult and embryonic (E16.5) kidney, gut, lung and heart. Expression of Kid3 in the kidney is developmentally regulated and suggests a role for Kid3 in the early stages of nephrogenesis.

Characterization of the mouse Kid1 gene and identification of a highly related gene, Kid2.

Kid1 encodes a zinc finger protein that has been implicated in renal cell differentiation. Levels of Kid1 mRNA correlate with maturation of kidney tubule epithelia in rat post-natal kidney development and during kidney regeneration following injury. KID1 is a putative transcriptional repressor, containing a KRAB domain at its amino terminus that mediates transcriptional repression in transient cell transfection assays when fused to a heterologous DNA-binding domain. In this paper, we describe the isolation and characterization of the mouse homologue of Kid1 and the identification of a novel highly related mouse gene, Kid2, Kid1 and Kid2 are tightly linked on mouse chromosome 11 and show conservation across mammals. Both genes are expressed predominantly in the mouse adult kidney and brain, but transcripts are also detected in embryonic brain, kidney, gut and lung, suggesting an additional role for these genes during mouse development.

Rectal thermoluminescent dosimeter measurements using the MicroSelectron High Dose Rate afterloader in postoperative intravaginal radiation cases.

PURPOSE: The purpose of this study is twofold: First, to measure the dose distribution along the anterior and posterior rectal wall, compare them to the prescribed dose and establish the rectal length receiving the maximum dose. Second, to carry out in-phantom dose measurements in order to confirm that the dose planned is in fact the dose delivered. METHODS AND MATERIALS: The dose distribution along the anterior and posterior rectal wall was measured for a group of 25 Gynecologic cases treated with a vaginal cylinder, using the MicroSelectron High Dose Rate system. The method of measurement employed flexible vinyl rectal probes (1 or 2 cm diameter). Two fine plastic tubes, each containing 15 Thermo Luminescent Dosimeters rods, were attached along the probe on opposite sides to measure the anterior and posterior rectal wall dose distributions. RESULTS: The dose distribution exhibited a sharp peak covering a rectal length from one to two centimeters. The peak doses for the anterior rectal wall ranged from 60% to 110% of prescribed dose. In-phantom measurements used layers of phantom material that contained a special source tube for the Iridium-192 source as well as Thermoluminescent Dosimeter tube(s) positioned at 1 cm distance from the source tube. The afterloader was programmed to deliver 300 cGy at 1 cm along its treatment length. CONCLUSION: The Thermo Luminescent Dosimeters measurements showed good agreement with the doses expected on the basis of the treatment plan.

Oligodendrocyte development in the spinal cord and telencephalon: common themes and new perspectives.

There are clear parallels between oligodendrocyte development in the spinal cord and forebrain. However, there is new evidence that in both of these regions oligodendrocyte lineage development may be more complex than we earlier thought. This stems from the recent identification of three new transcription factor genes, Olig1, Olig2 and Sox10, that are expressed from the early stages of oligodendrocyte lineage development. In this article, we highlight the common themes underlying specification and early development of oligodendrocytes in the spinal cord and telencephalon. Then, we discuss recent studies of Sox10 and the Olig genes and their implications for oligodendrocyte specification. We conclude that although the mechanisms of oligodendrogenesis appear to be fundamentally similar at different rostro-caudal levels of the neuraxis, there are still many unanswered questions about the details of oligodendrocyte specification.

Transverse axial film tomography with a therapy simulator.

A tomographic attachment was designed and developed that attaches to our existing simulator. The film tomograms obtained with the aid of this device exhibit very low geometrical distortion and good contrast and resolution for the objects used in this investigation. In addition, our results to date show that adjacent areas with densities differing by as little as 5% can be distinguished on film.

HLA antibody-incompatible kidney transplantation between jehovah's witnesses--a case report.

Desensitization before HLA antibody-incompatible (HLAi) transplantation involves nonspecific apheresis of HLA antibodies. Clotting factors and albumin are also removed and have to be replaced. This makes transplantation difficult because it increases the risk of bleeding. Such risk is further compounded when certain blood products are refused on religious grounds. We present a case of successful HLAi transplantation in a Jehovah's Witness across a positive-flow cytometric HLA crossmatch from a live donor who was also a Jehovah's Witness. This was achieved by giving rituximab 1 month before transplantation and starting prednisolone, tacrolimus, and mycophenolate mofetil 10 days before surgery. In preparation, the patient also underwent 4 sessions of double-filtration plasma exchange each followed by low-dose intravenous immunoglobulin. The night before transplantation, the fibrinogen was low, requiring 2 pools of cryoprecipitate. The organ was retrieved through laparoscopic hand-assisted retroperitoneoscopic nephrectomy and transplanted into the recipient with no complications. In addition, the patient received basiliximab during surgery. Sixteen months after transplantation the serum creatinine was 70 µmol/L (0.79 mg/dL) and there were no rejection episodes. To our knowledge this is the world's first live-related kidney transplant across the HLAi barrier between 2 Jehovah's Witnesses. This case may allow further HLAi transplants to be carried out in Jehovah's Witnesses in the future around the world.

A successful live donor kidney transplantation after large angiomyolipoma excision.

INTRODUCTION: Angiomyolipoma is the most common benign neoplasm of the kidney. Successful transplantation of an AML affected kidney has been reported. However it is still often seen as a contraindication to transplantation. PRESENTATION OF CASE: A 47-year-old female underwent assessment for a direct specified kidney donation to her husband who had end stage renal failure, due to adult polycystic kidney disease. Routine pre-operative CT angiography demonstrated a large 6cm×4cm AML arising from the upper pole of the right kidney. Right-side hand assisted retro-peritoneoscopic live donor nephrectomy with bench tumour excision was subsequently performed. Recipient implantation was unremarkable with no haemorrhage. DISCUSSION: Histology confirmed a 7cm AML. At 36 months follow up, the recipient's serum creatinine was 158µmol/l and eGFR 40ml/min without the need for dialysis at any stage. CONCLUSION: AML should not be a contraindication for specified live kidney donation, despite a size of 7cm.

Hyperthermia and low dose-rate irradiation.

Hyperthermia combined with 60Co gamma irradiation was studied using V79 hamster cells cultured in vitro. Modest hyperthermia (41 degrees C for 6 hrs.) enhanced the cell killing produced by acute exposure to radiation. The same treatment enhanced the effect of low dose-rate irradiation (200 rads/hr.) even more. The sequence in which modest hyperthermia was combined with low dose-rate irradiation was important. Maximal enhancement was observed when hyperthermia was followed by irradiations. The probable explanation is that, by damaging the repair system, prior heat renders the cells unable to repair sublethal damage during subsequent low dose-rate irradiation.