Comparison of the internal energy deposition of Venturi-assisted electrospray ionization and a Venturi-assisted array of micromachined ultrasonic electrosprays (AMUSE).

The internal energy deposition of a Venturi-assisted array of micromachined ultrasonic electrosprays (AMUSE), with and without the application of a DC charging potential, is compared with equivalent experiments for Venturi-assisted electrospray ionization (ESI) using the "survival yield" method on a series of para-substituted benzylpyridinium salts. Under conditions previously shown to provide maximum ion yields for standard compounds, the observed mean internal energies were nearly identical (1.93-2.

Discussing withdrawing and withholding of life-sustaining medical treatment in a tertiary paediatric hospital: a survey of clinician attitudes and practices.

Aim: To better understand current attitudes and practices relating to discussions concerning the withholding and withdrawing of life-sustaining medical treatment (WWLSMT) among medical staff in the paediatric setting.

Methods: An anonymous online survey of paediatricians (senior medical staff - SMS) and paediatric trainees (junior medical staff - JMS) likely to be involved in the care of children with life limiting illness.

Results: A total of 162 responses were obtained (response rate 42%).

Palliation via hybrid procedure of a 1.4-kg patient with a hypoplastic left heart.

Despite improvements in survival of patients with hypoplastic left heart syndrome (HLHS) with various palliative procedures, certain risk factors, such as weight less than 2.5 kg, continue to predict increased mortality. We report the palliation of a patient with HLHS weighing 1.

Repositioning a dislodged new lumenless pacing lead: a simple tool and technique.

The SelectSecure catheter delivery system and active fixation 4.1 French diameter Model 3830 pacing lead (Medtronic, Inc, Minneapolis, MN, USA) has the advantage of permitting precise implant at nearly any desired location due to catheter maneuverability. However, as the lead lacks an internal stylet lumen, it is intrinsically floppy and any repositioning after the delivery catheter is removed is nearly impossible, necessitating lead extraction and a repeat of the implant process.

Acute lower extremity ischemia secondary to salivary gland tumor embolus.

Malignant arterial tumor emboli of sufficient size that is capable of causing organ infarction or ischemia are exceedingly rare. The majority of these emboli are associated with either primary or secondary pulmonary malignancies and commonly occur perioperatively or immediately postoperatively. This study describes an unusual case of acute lower extremity ischemia secondary to a malignant parotid tumor embolus with evidence of left ventricular involvement.

Synthesis, structure, and infrared spectroscopy of the first Np5+ neptunyl silicates, Li6(NpO2)4(H2Si2O7)(HSiO4)2(H2O)4 and K3(NpO2)3(Si2O7).

Two Np(5+) silicates, Li(6)(NpO(2))(4)(H(2)Si(2)O(7))(HSiO(4))(2)(H(2)O)(4) (LiNpSi1) and K(3)(NpO(2))(3)(SiO(3)OH)(2) (KNpSi1), were synthesized by hydrothermal methods. The crystal structures were determined using direct methods and refined on the basis of F(2) for all unique data collected with Mo Kalpha radation and an APEX II CCD detector. LiNpSi1 crystallizes in orthorhombic space group Pnma with a =13.

Multiplexed operation of a micromachined ultrasonic droplet ejector array.

A dual-sample ultrasonic droplet ejector array is developed for use as a soft-ionization ion source for multiplexed mass spectrometry (MS). Such a multiplexed ion source aims to reduce MS analysis time for multiple analyte streams, as well as allow for the synchronized ejection of the sample(s) and an internal standard for quantitative results and mass calibration. Multiplexing is achieved at the device level by division of the fluid reservoir and separating the active electrodes of the piezoelectric transducer for isolated application of ultrasonic wave energy to each domain.

Analytical performance of a venturi-assisted array of micromachined ultrasonic electrosprays coupled to ion trap mass spectrometry for the analysis of peptides and proteins.

The analytical characterization of a novel ion source for mass spectrometry named array of micromachined ultrasonic electrosprays (AMUSE) is presented here. This is a fundamentally different type of ion generation device, consisting of three major components: (1) a piezoelectric transducer that creates ultrasonic waves at one of the resonant frequencies of the sample-filled device, (2) an array of pyramidally shaped nozzles micromachined on a silicon wafer, and (3) a spacer which prevents contact between the array and transducer ensuring the transfer of acoustic energy to the sample. A high-pressure gradient generated at the apexes of the nozzle pyramids forces the periodic ejection of multiple droplet streams from the device.

Intermediate follow-up following intravascular stenting for treatment of coarctation of the aorta.

Background: We report a multiinstitutional study on intermediate-term outcome of intravascular stenting for treatment of coarctation of the aorta using integrated arch imaging (IAI) techniques.

Methods And Results: Medical records of 578 patients from 17 institutions were reviewed. A total of 588 procedures were performed between May 1989 and Aug 2005.

Prevention of contrast-induced nephropathy in vascular surgery patients.

Presently, only hydration and N-acetylcysteine have been shown to be effective in decreasing the incidence of radiographic contrast-induced nephropathy. We investigated the role of N-acetylcysteine and various hydration protocols in vascular surgery patients undergoing angiography. A single-center, randomized, placebo-controlled trial was conducted in patients with stable, preexisting renal dysfunction undergoing elective, outpatient angiography.

Kearns-Sayre syndrome presenting as complete heart block.

Kearns-Sayre syndrome (KSS) is a rare mitochondrial disorder characterized by large-scale deletions of mitochondrial DNA. Neuromuscular and cardiac conduction systems are most commonly involved in these patients. Here, we discuss a 10-year-old patient with diabetes mellitus who presented in complete heart block leading to the diagnosis of KSS.

Midterm results of endovascular infrarenal abdominal aortic aneurysm repair in high-risk patients.

Short-term and midterm clinical outcomes after endovascular repair of abdominal aortic aneurysms (AAAs) have been well documented. Evaluation of longer term outcomes is now possible. Here we describe our initial 100 high-risk patients treated with endovascular aneurysm repair (EVAR), all with a minimum of 5 years of follow-up.

Structure determination and infrared spectroscopy of K(UO2)(SO4)(OH)(H2O) and K(UO2)(SO4)(OH).

Two potassium uranyl sulfate compounds were synthesized, and their crystal structures were determined by single-crystal X-ray diffraction. K(UO2)(SO4)(OH)(H2O) (KUS1) crystallizes in space group P21/c, a = 8.0521(4) A, b = 7.

Procedural results and acute complications in stenting native and recurrent coarctation of the aorta in patients over 4 years of age: a multi-institutional study.

Background: We report a multi-institutional experience with intravascular stenting (IS) for treatment of coarctation of the aorta.

Methods And Results: Data was collected retrospectively by review of medical records from 17 institutions. The data was broken down to prior to 2002 and after 2002 for further analysis.

Transcatheter closure of high-risk muscular ventricular septal defects with the CardioSEAL occluder: initial report from the CardioSEAL VSD registry.

Objectives: The CardioSEAL VSD registry was created to track safety of the device to close high-risk Ventricular Septal Defect (VSD).

Background: This is the first report from the multi-centered CardioSEAL VSD registry reviewing demographics and initial results.

Methods: Centers recruited patients with VSD who were high-risk for surgery due to medical condition or anatomic features.

Learning curve analysis of thoracic endovascular aortic repair in relation to credentialing guidelines.

Objective: Recently, practice guideline documents have recommended the completion of different levels of interventional experience and 5 or 10 thoracic endovascular aortic cases prior to surgeon credentialing. This study's purpose was to determine whether these requirements are valid by reviewing three surgeons' learning curves with thoracic aortic endovascular repairs.

Methods: Between 1998 and 2006, 67 patients underwent emergent or elective endovascular repair of thoracic aortic pathologies by one of three vascular surgeons with extensive experience with catheter manipulation and abdominal aortic endografts.

Endovascular repair of thoracic aortic disease: early and midterm experience.

Thoracic aorta disease remains a challenging problem, and despite improvements, open repair techniques are still associated with significant morbidity and mortality. This is a retrospective review of 53 consecutive patients with thoracic aortic pathology who were treated with endovascular repair between September 1998 and December 2004 at a tertiary-care hospital. Endovascular stent graft placement was performed on 23 elective and 30 emergent patients (34 male patients, mean age 66 years, 21 to 85 years).

Objective scoring systems of medical risk: a clinical tool for selecting patients for open or endovascular abdominal aortic aneurysm repair.

Background: Objective scoring systems have been developed for risk stratification of open infrarenal aneurysm repair. To date, none have been applied for the selection of patients who would most benefit from either an open or an endovascular approach. This study assessed the utility of comorbidity-based objective scoring systems for defining subgroups of patients who might most benefit from open or endovascular aneurysm repair.

Determination of functional outcome following upper extremity arterial trauma.

Upper extremity arterial trauma may lead to significant disability with a poor functional outcome. This study represents a retrospective review of all trauma patients presenting to a university-affiliated medical center. Patients suffering from upper extremity arterial injuries requiring treatment were identified.

The effect of patient transfer on outcomes after rupture of an abdominal aortic aneurysm.

Objective: Centralization of vascular surgery services has resulted in patients being transferred longer distances for treatment of life-threatening conditions. The purpose of this study was to determine whether patient transfer adversely affects the survival of people with a ruptured abdominal aortic aneurysm (RAAA).

Methods: We performed a retrospective review of all patients undergoing attempted repair of an RAAA at our centre, over a recent 3.

Expanding the crystal chemistry of uranyl peroxides: synthesis and structures of di- and triperoxodioxouranium(VI) complexes.

Four compounds containing tri- and diperoxodioxouranium(VI) complexes have been synthesized under ambient conditions and structurally characterized. The crystal structures of Na4(UO2)(O2)3(H2O)12 (monoclinic, P21/c, a=6.7883(6) A, b=16.