Direct Synthesis and Characterization of Hydrophilic Cu-Deficient Copper Indium Sulfide Quantum Dots.

Copper indium sulfide (CIS) nanocrystals constitute a promising alternative to cadmium- and lead-containing nanoparticles. We report a synthetic method that yields hydrophilic, core-only CIS quantum dots, exhibiting size-dependent, copper-deficient composition and optical properties that are suitable for direct coupling to biomolecules and nonradiative energy transfer applications. To assist such applications, we complemented previous studies covering the femtosecond-picosecond time scale with the investigation of slower radiative and nonradiative processes on the nanosecond time scale, using both time-resolved emission and transient absorption.

Direct observation of triplet energy transfer between chlorophylls and carotenoids in the core antenna of photosystem I from Thermosynechococcus elongatus.

Quenching of chlorophyll triplet states by carotenoids is an essential photoprotective process, which prevents formation of reactive singlet oxygen in photosynthetic light-harvesting complexes. The process is usually very efficient in oxygenic organisms under physiological conditions, thus preventing any observable accumulation of chlorophyll triplets. However, it subsequently prevents also the determination of the triplet transfer rate.

Interplay between coherence-time undersampling and scattered light in two-dimensional electronic spectroscopy.

Scanning pulse delays in multi-pulse non-linear optical spectroscopy experiments is a major contributor to lengthy data acquisition. Using large steps for the scan can significantly speed up the experiment. However, an improper choice of step length can cause distortions to the resulting spectra, especially if the light scattered on the sample is mixed into the signal.

Temperature Dependence of Chlorophyll Triplet Quenching in Two Photosynthetic Light-Harvesting Complexes from Higher Plants and Dinoflagellates.

Chlorophyll (Chl) triplet states generated in photosynthetic light-harvesting complexes (LHCs) can be quenched by carotenoids to prevent the formation of reactive singlet oxygen. Although this quenching occurs with an efficiency close to 100% at physiological temperatures, the Chl triplets are often observed at low temperatures. This might be due to the intrinsic temperature dependence of the Dexter mechanism of excitation energy transfer, which governs triplet quenching, or by temperature-induced conformational changes.

Quenching of chlorophyll triplet states by carotenoids in algal light-harvesting complexes related to fucoxanthin-chlorophyll protein.

We have used time-resolved absorption and fluorescence spectroscopy with nanosecond resolution to study triplet energy transfer from chlorophylls to carotenoids in a protective process that prevents the formation of reactive singlet oxygen. The light-harvesting complexes studied were isolated from Chromera velia, belonging to a group Alveolata, and Xanthonema debile and Nannochloropsis oceanica, both from Stramenopiles. All three light-harvesting complexes are related to fucoxanthin-chlorophyll protein, but contain only chlorophyll a and no chlorophyll c.

Discrimination of Diverse Coherences Allows Identification of Electronic Transitions of a Molecular Nanoring.

The role of quantum coherence in photochemical functions of molecular systems such as photosynthetic complexes is a broadly debated topic. Coexistence and intermixing of electronic and vibrational coherences has been proposed to be responsible for the observed long-lived coherences and high energy transfer efficiency. However, clear experimental evidence of coherences with different origins operating at the same time has been elusive.

Triplet-triplet energy transfer from chlorophylls to carotenoids in two antenna complexes from dinoflagellate Amphidinium carterae.

Room temperature transient absorption spectroscopy with nanosecond resolution was used to study quenching of the chlorophyll triplet states by carotenoids in two light-harvesting complexes of the dinoflagellate Amphidinium carterae: the water soluble peridinin-chlorophyll protein complex and intrinsic, membrane chlorophyll a-chlorophyll c2-peridinin protein complex. The combined study of the two complexes facilitated interpretation of a rather complicated relaxation observed in the intrinsic complex. While a single carotenoid triplet state was resolved in the peridinin-chlorophyll protein complex, evidence of at least two different carotenoid triplets was obtained for the intrinsic light-harvesting complex.

Risk tolerance to MS therapies: Survey results from the NARCOMS registry.

Background: There is little information about risk acceptance of multiple sclerosis (MS) patients to various MS therapies.

Objective: To determine MS patients׳ tolerance to risky therapies and identify associated characteristics.

Methods: MS patients from the North American Research Committee on Multiple Sclerosis (NARCOMS) Registry׳s online cohort were invited to complete questionnaires on decision making and risk tolerance (RT) to two therapeutic scenarios: a theoretical cure for MS [CureMS], with permanent reversal of all MS symptoms but a risk of immediate painless death; and natalizumab [NAT], a real-life scenario with benefits and risks as defined by Phase III trial results.

Energy transfer in aggregates of bacteriochlorophyll c self-assembled with azulene derivatives.

Bacteriochlorophyll (BChl) c is the main light-harvesting pigment of certain photosynthetic bacteria. It is found in the form of self-assembled aggregates in the so-called chlorosomes. Here we report the results of co-aggregation experiments of BChl c with azulene and its tailored derivatives.

Renal transplantations in African Americans: a single-center experience of outcomes and innovations to improve access and results.

Objective: To report a single-center 10-year experience of outcomes of kidney transplantation in African Americans (AAs) vs Caucasian Americans (CA) and to propose ways in which to improve kidney transplant outcomes in AAs, increased access to kidney transplantation, prevention of kidney disease, and acceptance of organ donor registration rates in AAs.

Methods: We compared outcomes of deceased donor (DD) and living donor (LD) renal transplantation in AAs vs CAs in 772 recipients of first allografts at our transplant center from January 1995 to March 2004. For DD and LD transplants, no significant differences in gender, age, body mass index, or transplant panel reactive antibody (PRA) existed between AA and CA recipients.

Freestanding sample holder for ultrafast optical spectroscopy at low temperatures.

Ultrafast optical spectroscopy techniques are often employed to gain information about samples that are liquid at room temperature and frozen at cryogenic temperatures. However, the measurements suffer from the presence of unwanted, non-resonant signals originating in the sample cell walls. Most of these artifacts can be avoided in the measurements performed at room temperature by using liquid jet systems, i.

2D spectroscopy study of water-soluble chlorophyll-binding protein from Lepidium virginicum.

Water-soluble chlorophyll-binding proteins (WSCPs) are interesting model systems for the study of pigment-pigment and pigment-protein interactions. While class IIa WSCP has been extensively studied by spectroscopic and theoretical methods, a comprehensive spectroscopic study of class IIb WSCP was lacking so far despite the fact that its structure was determined by X-ray crystallography. In this paper, results of two-dimensional electronic spectroscopy applied to the class IIb WSCP from Lepidium virginicum are presented.

Prediction of intraoperative transfusion requirements during orthotopic liver transplantation and the influence on postoperative patient survival.

Background: Predicting blood product transfusion requirements during orthotopic liver transplantation (OLT) remains difficult. Our primary aim in this study was to determine which patient variables best predict recipient risk for large blood transfusion requirements during OLT. The secondary aim was to determine whether the amount of blood products transfused during OLT impacted patient survival.

Low-temperature spectroscopy of bacteriochlorophyll c aggregates.

Chlorosomes from green photosynthetic bacteria belong to the most effective light-harvesting antennas found in nature. Quinones incorporated in bacterichlorophyll (BChl) c aggregates inside chlorosomes play an important redox-dependent photo-protection role against oxidative damage of bacterial reaction centers. Artificial BChl c aggregates with and without quinones were prepared.

An HIV-1 replication pathway utilizing reverse transcription products that fail to integrate.

Integration is a central event in the replication of retroviruses, yet ≥ 90% of HIV-1 reverse transcripts fail to integrate, resulting in accumulation of unintegrated viral DNA in cells. However, understanding what role, if any, unintegrated viral DNA plays in the natural history of HIV-1 has remained elusive. Unintegrated HIV-1 DNA is reported to possess a limited capacity for gene expression restricted to early gene products and is considered a replicative dead end.

Association of histologic variants in FSGS clinical trial with presenting features and outcomes.

Background And Objectives: FSGS histologic variants have correlated with outcomes in retrospective studies. The FSGS Clinical Trial provided a unique opportunity to study the clinical impact of histologic variants in a well defined prospective cohort with steroid-resistant primary FSGS.

Design, Setting, Participants, & Measurements: Renal biopsies of 138 FSGS Clinical Trial participants aged 2-38 years enrolled from 2004 to 2008 were analyzed using the Columbia classification by core pathologists.

Impact of pulmonary hemodynamics on 6-min walk test in idiopathic pulmonary fibrosis.

Objectives: Pulmonary hypertension (PH) has been associated with decreased functional capacity in patients with advanced idiopathic pulmonary fibrosis (IPF). We aimed to evaluate the true impact of altered pulmonary hemodynamics on functional capacity in a cohort of patients with IPF.

Methods: Between January 1990 and December 2007, 124 patients [73M/51F; 111 Caucasians] with IPF underwent right heart catheterization and 6-min walk test (6MWT).

Isolation and identification of a bacteriocin with antibacterial and antibiofilm activity from Citrobacter freundii.

Multi- and pan-antibiotic-resistant bacteria area major health challenge in hospital settings. Furthermore,when susceptible bacteria establish surface-attached biofilm populations, they become recalcitrant to antimicrobial therapy. Therefore, there is a need for novel antimicrobials that are effective against multi-drug-resistant and surface-attached bacteria.

Self-assembly and energy transfer in artificial light-harvesting complexes of bacteriochlorophyll c with astaxanthin.

Chlorosomes, the light-harvesting antennae of green photosynthetic bacteria, are based on large aggregates of bacteriochlorophyll molecules. Aggregates with similar properties to those in chlorosomes can also be prepared in vitro. Several agents were shown to induce aggregation of bacteriochlorophyll c in aqueous environments, including certain lipids, carotenes, and quinones.

Sensory discrimination of teeth and implant-supported restorations.

Purpose: The purpose of this study was to examine patient responses to load application on natural teeth and implants using a visual analog scale (VAS).

Materials And Methods: Ten subjects were selected from the University of Medicine and Dentistry of New Jersey patient pool who had a single implant-supported crown restoration adjacent to a natural tooth. Vibrational loads of 0.

Adenosine restores the hepatic artery buffer response and improves survival in a porcine model of small-for-size syndrome.

The aim of the study is to define the role of the HABR in the pathophysiology of the SFS liver graft and to demonstrate that restoration of hepatic artery flow (HAF) has a significant impact on outcome and improves survival. Nine pigs received partial liver allografts of 60% liver volume, Group 1; 8 animals received 20% LV grafts, Group 2; 9 animals received 20% LV grafts with adenosine infusion, Group 3. HAF and portal vein flow (PVF) were recorded at 10 min, 60 min and 90 min post reperfusion, on POD 3 and POD 7 in Group 1, and daily in Group 2 and 3 up to POD 14.

Nomograms for predicting graft function and survival in living donor kidney transplantation based on the UNOS Registry.

Purpose: We developed nomograms that predict transplant renal function at 1 year (Modification of Diet in Renal Disease equation [estimated glomerular filtration rate]) and 5-year graft survival after living donor kidney transplantation.

Materials And Methods: Data for living donor renal transplants were obtained from the United Network for Organ Sharing registry for 2000 to 2003. Nomograms were designed using linear or Cox regression models to predict 1-year estimated glomerular filtration rate and 5-year graft survival based on pretransplant information including demographic factors, immunosuppressive therapy, immunological factors and organ procurement technique.

Should lung transplantation be performed using donation after cardiac death? The United States experience.

Objective: We compared 1) survival after lung transplantation of recipients of donation after cardiac death (DCD) versus brain death donor organs in the United States and 2) recipient characteristics.

Methods: Data were obtained from the United Network for Organ Sharing for lung transplantation from October 1987 to May 2007. Follow-up after DCD lung transplantation extended to 8.

Challenges in the diagnosis and management of Nocardia infections in lung transplant recipients.

Background: Nocardia infection occurs in 2.1-3.5% of lung transplant recipients, and may involve cavitary nodular pulmonary lesions, soft tissue infection, or other sites of dissemination.