Early expression of mature αβ TCR in CD4CD8 T cell progenitors enables MHC to drive development of T-ALL bearing NOTCH mutations.

During normal T cell development in mouse and human, a low-frequency population of immature CD4CD8 double-negative (DN) thymocytes expresses early, mature αβ T cell antigen receptor (TCR). We report that these early αβ TCR+ DN (EADN) cells are DN3b-DN4 stage and require CD3δ but not major histocompatibility complex (MHC) for their generation/detection. When MHC - is present, however, EADN cells can respond to it, displaying a degree of coreceptor-independent MHC reactivity not typical of mature, conventional αβ T cells.

Anterior Vertebral Body Tethering for Adolescent Scoliosis with Growth Remaining: A Retrospective Review of 2 to 5-Year Postoperative Results.

Background: Anterior vertebral body tethering (VBT) is an early treatment option for progressive scoliosis in pediatric patients, allowing for continued deformity correction during normal growth. We report postoperative radiographic and clinical outcomes for patients treated with VBT.

Methods: This clinical and radiographic retrospective review of 31 consecutive patients included an analysis of preoperative, perioperative, and postoperative details, including the Lenke classification; Cobb angle measurements of the proximal thoracic, main thoracic, and lumbar curves; the sagittal profile; and skeletal maturity.

Inguinal Hernia in Premature Infants.

Inguinal hernia is a common problem affecting infants in the NICU. As a group, preterm infants have the highest incidence of inguinal hernia and this risk increases as gestational age decreases. The etiopathologic factors leading to the development of an inguinal hernia are not clear and interventions to alter these factors have not been thoroughly investigated.

Investigation of antibacterial phytochemicals in the bark and leaves of Ficus coronata by high-performance liquid chromatography-electrospray ionization-ion trap mass spectrometry (HPLC-ESI-MS(n) ) and ESI-MS(n).

The ethyl acetate extracts of the bark and leaves of Ficus coronata were separated by column chromatography and the resulting fractions tested for their bioactivity toward methicillin-resistant-Staphylococcus aureus (MRSA) and M. luteus. The bioactive column chromatography fractions were further separated by preparative thin layer chromatography (TLC) and the resulting bands investigated by high-performance liquid chromatography-electrospray ionization-ion trap mass spectrometry (HPLC-ESI-MS(n) ) and ESI-MS(n) .

The characterisation of coumarins from selected structural classes by electrospray ionisation quadrupole time-of-flight tandem mass spectrometry.

Electrospray ionisation quadrupole time-of-flight tandem mass spectrometry (ESI-QTOF-MS/MS) has been used for characterisation of a selection of naturally occurring and synthetic coumarins from different structural classes. The product ions, suggested in earlier studies by electrospray ionisation ion trap mass spectrometry (ESI-MS(n)), are unequivocally established for the representative coumarins by virtue of accurate mass measurement. Synthetic coumarins that are unsubstituted in the heterocyclic ring give rise to a major product ion by loss of CO(2), whereas those substituted in the heterocyclic ring generally undergo alternative fragmentation releasing neutral species such as ketene or methyl ketene.

Intraoperative diagnosis of unsuspected methemoglobinemia due to low pulse oximetry values.

Methemoglobinemia results from the oxidation of the iron in the hemoglobin molecule from the ferrous to the ferric state. Methemoglobinemia may result from congenital deficiencies of enzymes that normally convert methemoglobin (metHb) to hemoglobin, alterations in the hemoglobin molecule itself or, most commonly, from medications or toxins. As metHb cannot carry oxygen, clinical sequelae result when the concentration of metHb is high enough to compromise oxygen delivery to the tissues.

Perioperative care of a child with Ullrich congenital muscular dystrophy.

Ullrich congential muscular dystrophy (UCMD) is a severe form of congenital muscular dystrophy manifesting axial muscle contractures and distal joint hyperlaxity. Severe hypotonia and associated respiratory failure may occur early in the disease process. Given the various associated orthopedic conditions, anesthetic management may be required during surgical interventions to correct skeletal deformities or these patients may present with surgical conditions unrelated to their primary illness.

Clevidipine controls intraoperative blood pressure in an adolescent with renal failure.

In pediatric-aged patients, various factors may result in perioperative hypertension including renal failure or insufficiency, volume overload, or other factors that activate the sympathetic nervous system including pain and agitation. Perioperative blood pressure control may be even more difficult to achieve and maintain in patients with pre-existing hypertension. We present a 16-year-old adolescent with renal failure and hypertension who presented for anesthetic care during placement of a peritoneal dialysis catheter.

A study of the analytical behaviour of selected psycho-active drugs using liquid chromatography, ion trap mass spectrometry, gas chromatography and polarography and the construction of an appropriate database for drug characterisation.

This paper provides analytical chemical information on a range of psycho-active drugs. This analytical chemical information on liquid chromatography-electrospray ionisation-mass spectrometry (HPLC-ESI-MS), ion trap mass spectrometry (ESI-MS(n)), gas chromatography-flame ionisation detection (GLC-FID) and polarographic behaviour is then incorporated into a database which is of use in drug characterisation. Application is found in the determination of selected drug compounds in hair samples.

The characterisation of selected drugs with amine-containing side chains using electrospray ionisation and ion trap mass spectrometry and their determination by HPLC-ESI-MS.

The electrospray ionisation-ion-trap mass spectrometry (ESI-MS(n)) of selected drug compounds with amine-containing side chains has been investigated. Certain characteristic in-source fragmentations have been observed for these molecules. Sequential product ion fragmentation experiments (MS(n)) have been performed in order to elucidate the degradation pathways for the [M + H](+) ions and their predominant fragment ions.

Aortic hiatus gastric hernia.

Congenital diaphragmatic hernias are a relatively common anomaly that can present with significant respiratory morbidity and mortality. We report on a case of an aortic-hiatal gastric hernia that initially presented with repeated episodes of respiratory distress, which was diagnosed as asthma. The diagnosis of a diaphragmatic hernia was made at 18 months of age.

Characterisation of selected drugs with nitrogen-containing saturated ring structures by use of electrospray ionisation with ion-trap mass spectrometry.

The electrospray ionisation-ion-trap mass spectrometry (ESI-MS(n)) of selected drugs with nitrogen-containing saturated ring structures has been investigated. Sequential product-ion fragmentation experiments (MS(n)) have been performed to elucidate degradation pathways for the [M+H](+) ions and their predominant fragment ions. These MS(n) experiments result in characteristic fragmentations in which functional groups are generally cleaved from the ring systems as neutral molecules such as H(2)O, amines, alkenes, esters, carboxylic acids, etc.

Short course induction immunosuppression with thymoglobulin for renal transplant recipients.

Background: The aim of this study was to demonstrate that 3-days of induction immunosuppression with thymoglobulin was as effective and safe as a 7-day course and reduced initial hospitalization after transplantation.

Methods: This was a prospective, nonrandomized trial of 40 consecutive patients receiving thymoglobulin induction for 3 days and followed for 1 year. An historical group of 48 patients that received 7 days of thymoglobulin served as controls.