Activity-based fluorescent reporters for monoamine oxidases in living cells.

Monoamine Oxidase Reporters 1 and 2 (MR1 and MR2) are substrate-tethered activity probes that utilize a tandem amine oxidation/beta-elimination mechanism to detect MAO chemistry in vitro and in living cells directly and specifically without the need for additional enzymes or other activating reagents.

Fluorescent probes for nitric oxide and hydrogen peroxide in cell signaling.

Nitric oxide (NO) and hydrogen peroxide (H(2)O(2)) have emerged as essential small molecules for cellular signal transduction owing largely to their ability to mediate oxidative posttranslational modifications (PTMs). Inventing new ways to track these small, diffusible, and reactive species with spatial and temporal resolution is a key challenge in elucidating their chemistry in living systems. Recent progress in the development of fluorescent probes that respond selectively to NO and H(2)O(2) produced at cell signaling levels offers a promising approach to interrogating their physiological production, accumulation, trafficking, and function.

Theoretical studies on conjugated phenyl-cored thiophene dendrimers for photovoltaic applications.

Pi-conjugated dendrimers are an important class of materials for optoelectronic devices, especially for light-harvesting systems. We report here a theoretical investigation of the optical response and of the excited-state properties of three-arm and four-arm phenyl-cored dendrimers for photovoltaic applications. A variety of theoretical methods are used and evaluated against each other to calculate vertical transition energies, absorption and excitation spectra with vibronic structure, charge transport, and excitonic behavior upon photoexcitation and photoemission processes.

A new rat model links two contemporary theories in irritable bowel syndrome.

Rationale: Two proposed hypotheses for irritable bowel syndrome (IBS) are acute gastroenteritis and bacterial overgrowth. We studied whether acute infection with Campylobacter could precipitate bacterial overgrowth in a rat model in order to link the two hypotheses.

Methods: Sprague-Dawley outbred rats were randomly administered a vehicle or Campylobacter jejuni strain 81-176 by oral gavage.

Atomic resolution modeling of the ferredoxin:[FeFe] hydrogenase complex from Chlamydomonas reinhardtii.

The [FeFe] hydrogenases HydA1 and HydA2 in the green alga Chlamydomonas reinhardtii catalyze the final reaction in a remarkable metabolic pathway allowing this photosynthetic organism to produce H(2) from water in the chloroplast. A [2Fe-2S] ferredoxin is a critical branch point in electron flow from Photosystem I toward a variety of metabolic fates, including proton reduction by hydrogenases. To better understand the binding determinants involved in ferredoxin:hydrogenase interactions, we have modeled Chlamydomonas PetF1 and HydA2 based on amino-acid sequence homology, and produced two promising electron-transfer model complexes by computational docking.

Relationship of botulinum dosage to duration of side effects and normal voice in adductor spasmodic dysphonia.

Objective: Objective evaluation of botulinum toxin A (BTX-A) dosing by determination of the statistical relationship between injection amount and duration of side effects and normal voice in adductor spasmodic dysphonia (SD) patients. From this information, to provide a rational guide to determine the initial and follow-up BTX-A amounts for injection.

Study Design And Setting: Private laryngology clinic.

Preparation and use of Coppersensor-1, a synthetic fluorophore for live-cell copper imaging.

Coppersensor-1 (CS1) is a small-molecule, membrane-permeable fluorescent dye for imaging labile copper pools in biological samples, including live cells. This probe, comprising a boron dipyrromethene (BODIPY) chromophore coupled to a thioether-rich receptor, has a picomolar affinity for Cu+ with high selectivity over competing cellular metal ions. CS1 fluorescence increases up to 10-fold on binding to Cu+.

Molecular imaging of hydrogen peroxide produced for cell signaling.

Hydrogen peroxide (H2O2) is emerging as a newly recognized messenger in cellular signal transduction. However, a substantial challenge in elucidating its diverse roles in complex biological environments is the lack of methods for probing this reactive oxygen metabolite in living systems with molecular specificity. Here we report the synthesis and application of Peroxy Green 1 (PG1) and Peroxy Crimson 1 (PC1), two new fluorescent probes that show high selectivity for H2O2 and are capable of visualizing endogenous H2O2 produced in living cells by growth factor stimulation, including the first direct imaging of peroxide produced for brain cell signaling.

Laser nerve-sparing laparoscopic radical prostatectomy: a feasibility study.

Objective: To examine, in a pilot study, the feasibility of laser dissection of the neurovascular bundle (NVB) during nerve-sparing laparoscopic radical prostatectomy (NSLRP). NSLRP demands precise NVB mobilization with minimal collateral tissue trauma and optimal haemostasis. Unlike other methods of delivering energy, lasers have the potential to provide rapid, precise dissection with good haemostasis and minimal adjacent tissue injury.

A smart magnetic resonance contrast agent for selective copper sensing.

We describe the synthesis and properties of Copper-Gad-1 (CG1), a new type of smart magnetic resonance (MR) sensor for selective detection of copper. CG1 is composed of a gadolinium contrast agent core tethered to copper-selective recognition motif. Cu2+-induced modulation of inner-sphere water access to the Gd3+ center provides a sensing mechanism for reporting Cu2+ levels by reading out changes in longitudinal proton relaxivity values.

Comparison of outcomes after laparoscopic adjustable gastric banding in African-Americans and whites.

Background: Race may affect outcomes after bariatric surgery. This study compares outcomes in terms of weight loss and comorbidity resolution between African-Americans and whites after laparoscopic adjustable gastric banding (LAGB).

Methods: Data from 959 patients undergoing LAGB between July 2001 and July 2004 were prospectively collected and entered into an electronic registry.

Airborne environmental injuries and human health.

The concept that the environment in which we live can have detrimental effects on our health has existed for centuries. Obvious examples of substances that can cause human diseases include infectious agents, poisons, chemicals and other noxious agents, drugs, and physical stimuli such as bright lights and loud sounds. Some less obvious agents can include allergens, nontangible agents such as colorless, odorless gases and aerosolized toxins.

Campylobacter jejuni colonization of mice with limited enteric flora.

We have developed experimental murine Campylobacter infection models which demonstrate efficient establishment and reproducible, high-level colonization. Following oral inoculation, wild-type C3H mice with normal enteric flora were colonized inconsistently and inefficiently by C. jejuni strain 81-176.

The impact of obesity on laparoscopic radical prostatectomy.

Objective: To investigate the effect of obesity on the operative variables of patients undergoing laparoscopic radical prostatectomy (LRP).

Patients And Methods: The database entries and case-notes of 532 consecutive patients undergoing LRP from March 2000 to August 2005 were examined retrospectively. Complete data were available on 505 (95%) patients, 108 (21%) of whom were obese (body mass index, BMI, > or = 30 kg/m2).

A FRET-based approach to ratiometric fluorescence detection of hydrogen peroxide.

We report the synthesis, properties, and biological applications of Ratio-Peroxyfluor-1 (RPF1), a new ratiometric fluorescent reporter for hydrogen peroxide. RPF1 is comprised of a two-fluorophore cassette, where the spectral overlap between coumarin donor and fluoran/fluorescein acceptor partners can be controlled by the chemoselective peroxide-mediated deprotection of boronic ester pendants on the acceptor dye. RPF1 features good selectivity for hydrogen peroxide over a variety of reactive oxygen species, including superoxide and nitric oxide, a ca.

A selective fluorescent sensor for detecting lead in living cells.

We present the synthesis, properties, and biological applications of Leadfluor-1 (LF1), a new water-soluble, turn-on fluorescent sensor that is capable of selectively imaging Pb2+ in aqueous solution and in living cells. LF1 combines a fluorescein chromophore and a pseudocrown receptor to provide good selectivity for Pb2+ over a range of biologically and environmentally relevant metal ions in aqueous solution, with sensitivity to parts per billion EPA limits for allowable lead in drinking water. In addition to these attributes, imaging experiments further show that LF1 is the first small-molecule reagent that can be delivered into living cells and report changes in intracellular Pb2+ levels.

A selective turn-on fluorescent sensor for imaging copper in living cells.

We present the synthesis, properties, and biological applications of Coppersensor-1 (CS1), a new water-soluble, turn-on fluorescent sensor for intracellular imaging of copper in living biological samples. CS1 utilizes a BODIPY reporter and thioether-rich receptor to provide high selectivity and sensitivity for Cu+ over other biologically relevant metal ions, including Cu2+, in aqueous solution. This BODIPY-based probe is the first Cu+-responsive sensor with visible excitation and emission profiles and gives a 10-fold turn-on response for detecting this ion.