First Generation Amperometric Biosensing of Galactose with Xerogel-Carbon Nanotube Layer-By-Layer Assemblies.

A first-generation amperometric galactose biosensor has been systematically developed utilizing layer-by-layer (LbL) construction of xerogels, polymers, and carbon nanotubes toward a greater fundamental understanding of sensor design with these materials and the potential development of a more efficient galactosemia diagnostic tool for clinical application. The effect of several parameters (xerogel silane precursor, buffer pH, enzyme concentration, drying time and the inclusion of a polyurethane (PU) outer layer) on galactose sensitivity were investigated with the critical nature of xerogel selection being demonstrated. Xerogels formed from silanes with medium, aliphatic side chains were shown to exhibit significant enhancements in sensitivity with the addition of PU due to decreased enzyme leaching.

Functionalized carbon nanotube adsorption interfaces for electron transfer studies of galactose oxidase.

Modified electrodes featuring specific adsorption platforms able to access the electrochemistry of the copper containing enzyme galactose oxidase (GaOx) were explored, including interfaces featuring nanomaterials such as nanoparticles and carbon nanotubes (CNTs). Electrodes modified with various self-assembled monolayers (SAMs) including those with attached nanoparticles or amide-coupled functionalized CNTs were examined for their ability to effectively immobilize GaOx and study the redox activity related to its copper core. While stable GaOx electrochemistry has been notoriously difficult to achieve at modified electrodes, strategically designed functionalized CNT-based interfaces, cysteamine SAM-modified electrode subsequently amide-coupled to carboxylic acid functionalized single wall CNTs, were significantly more effective with high GaOx surface adsorption along with well-defined, more reversible, stable (≥ 8 days) voltammetry and an average ET rate constant of 0.

A diffractive mechanism of focusing.

We examine the free time evolution of a rectangular one dimensional Schrödinger wave packet of constant phase during the early stage which in the paraxial wave approximation is identical to the diffraction of a scalar field from a single slit. Our analysis, based on numerics and the Cornu spiral reveals considerable intricate detail behavior in the density and phase of the wave. We also point out a concentration of the intensity that occurs on axis and propose a new measure of width that expresses this concentration.

Realization of optical carpets in the Talbot and Talbot-Lau configurations.

Talbot and Talbot-Lau effects are frequently used in lensless imaging applications with light, ultrasound, x-rays, atoms and molecules--generally in situations where refractive optical elements are non-existent or not suitable. We here show an experimental visualization of the intriguing wave patterns that are associated with near-field interferometry behind a single periodic diffraction grating under plane wave illumination and which are often referred to as Talbot carpets or quantum carpets. We also show the patterns behind two separated diffraction gratings under nearly-monochromatic but spatially incoherent illumination that illustrate the nature of Talbot-Lau carpets.

Guanosine gel for sequence-dependent separation of polymorphic ssDNA.

The separation of fluorescent-labeled ssDNA fragments of equal length based on differences in sequence was achieved through the use of guanosine gels (G-gels) formed by guanosine-5'-monophosphate (GMP) in capillary gel electrokinetic chromatography (CGEKC) with LIF detection. Baseline resolution was achieved for homodimers and homopentamers of A, T, and C. G-gel CGEKC provided better resolution than CZE, MEKC, or a sieving gel in CGE.

Factors affecting morbidity, mortality and survival in patients undergoing surgery for rectal cancer in a district general hospital.

Introduction: This is a review of elective rectal cancer surgery during 1993-1999 at a single district general hospital to investigate the variables that affected the care of these patients.

Patients And Methods: A retrospective study of patients presenting with rectal adenocarcinoma to a district general hospital where total mesorectal excision was practiced over a 7-year period was performed to identify factors associated with complications, death and disease recurrence.

Results: Sixty-one patients developed a total of 89 complications and 30-day mortality was 8.

Psychomotor performance of long-term benzodiazepine users before, during, and after benzodiazepine discontinuation.

Long-term (mean, 8 years) users of benzodiazepines (BZs) were administered a small battery of cognitive tests on three occasions (before BZ taper, and 5 and 12 weeks post taper) as part of their BZ discontinuation program. Ninety-six patients had 5-week and 77 patients had 12-week data. For taper successes, BZ-free status was confirmed by weekly BZ plasma level determinations.

Nefazodone in major depression: adjunctive benzodiazepine therapy and tolerability.

One hundred sixty-six patients suffering from major depressive disorders were treated for 8 weeks with nefazodone in an open study in dosage ranges from 200 to 600 mg. This report focuses primarily on the first week of therapy and on the concomitant use of several benzodiazepines, one of which is not metabolized by the cytochrome system (temazepam). Triazolam response was further evaluated as a function of two nefazodone dosage regimens provided during the first week of therapy, one group receiving nefazodone 200 mg/day for 7 days, and another group receiving nefazodone 200 mg/day for 3 days, followed by 4 days with 400 mg/day.

Progesterone co-administration in patients discontinuing long-term benzodiazepine therapy: effects on withdrawal severity and taper outcome.

Since recent research has suggested that the major metabolites of progesterone are barbiturate-like modulators of GABAergic function, we undertook a pilot study of the efficacy of micronized progesterone in attenuating withdrawal and facilitating discontinuation in benzodiazepine-dependent patients with a minimum of 1 year of continuous daily use. Forty-three patients taking a mean daily dose of 16.2 mg of diazepam (or its equivalent) were assigned, doubleblind, to treatment with either placebo (n = 13) or progesterone (n = 30).

Long-term benzodiazepine users 3 years after participation in a discontinuation program.

Objective: Clinical status and use of benzodiazepines and other psychotropic drugs at follow-up were assessed in patients who had been chronically dependent on benzodiazepines and had been referred for participation in a discontinuation study.

Method: Of 123 benzodiazepine-dependent patients screened for entry into a tapered discontinuation program, 48 had completed the program, 38 had not, and 37 had not undergone drug tapering. Follow-up information was obtained through a structured telephone interview and a mail questionnaire that included a global severity scale assessing anxiety and depression and the Hopkins Symptom Checklist.

Carbamazepine treatment in patients discontinuing long-term benzodiazepine therapy. Effects on withdrawal severity and outcome.

Forty patients with a history of difficulty discontinuing long-term, daily benzodiazepine therapy were randomly assigned, under double-blind conditions, to treatment with carbamazepine (200 to 800 mg/d) or placebo. A gradual taper (25% per week reduction) off benzodiazepine therapy was then attempted. Five weeks after taper, significantly more patients who had received carbamazepine than placebo remained benzodiazepine free, this despite the fact that no statistically significant differences in withdrawal severity could be demonstrated.

Hepatic perfusion index (HPI) in mesenteric angina and following successful revascularization.

This is a case report of a 45 year old man who had previously undergone a small bowel resection for acute mesenteric ischaemia. He subsequently suffered from mesenteric angina due to stenosis of the origin of the superior mesenteric artery and intermittent claudication due to aorto-iliac atheroma. The patient underwent a successful aorto-bifemoral Y graft and small bowel revascularization with a saphenous vein graft between the Y graft and the accessible proximal portion of the superior mesenteric artery.

Long-term therapeutic use of benzodiazepines. II. Effects of gradual taper.

We compared the effect on withdrawal severity and acute outcome of a 25% per week taper of short half-life vs long half-life benzodiazepines in 63 benzodiazepine-dependent patients. Patients unable to tolerate taper were permitted to slow the taper rate. Ninety percent of patients experienced a withdrawal reaction, but it was rarely more than mild to moderate.

Long-term therapeutic use of benzodiazepines. I. Effects of abrupt discontinuation.

We compared the effect of abrupt discontinuation of therapeutic doses of short half-life and long half-life benzodiazepines in 57 benzodiazepine-dependent patients (daily use, greater than 1 year). Despite the use of a mean daily dose of 14.1 mg of diazepam equivalents, there were notable residual symptoms of anxiety and depression present at intake (Hamilton Rating Scale for Anxiety score, 17.

Aortocaval fistulas and the use of transvenous balloon tamponade.

Six cases of acute aortocaval fistula are reported, which illustrate the difficulties of diagnosis and management in a rare life-threatening condition. Five cases arose from spontaneous rupture of aortic aneurysms and one from trauma. In four cases the diagnosis was made before surgery.

Bilateral choroidal neonatal neuroblastoma.

We treated a bilateral, well-differentiated neuroblastoma of the choroid in a patient who had congenital abdominal neuroblastoma. Although orbital metastasis of neuroblastoma is common, intraocular metastasis is not. In our patient, there was no amplification of the N-myc oncogene in the tumor of either eye.

Benzodiazepine dependence: management of discontinuation.

This article discusses the management of benzodiazepine (BZ) withdrawal in patients who are chronically benzodiazepine dependent. Gradual benzodiazepine discontinuation is preferable to abrupt discontinuation, particularly for patients on short half-life benzodiazepines. For a small number of patients, replacement of short half-life with long half-life benzodiazepines may also be helpful.