The Effect of Light on Sleep and Sleep-Related Physiological Factors Among Patients in Healthcare Facilities: A Systematic Review.

Objectives: Lighting is one of the environmental factors which can improve patient sleep in healthcare environments. Due to the high degree of variation in study designs and results on this topic, the implications have been difficult to interpret. This review consolidates studies on the impact of bright light exposure on sleep to identify lighting conditions that can be applied and researched in future healthcare environments.

Synthesis and Evaluation of DNA Based Quantum Dot Fluorescence In Situ Hybridization (FISH) Probe for Telomere Detection.

Efficient oligonucleotide probe design and synthesis based on polymer-coated CdSe/ZnS quantum dot (QD) is demonstrated for detection of telomeres in human monocyte and Leishmania major, a protozoan pathogenic parasite. The highly photoluminescent polymer-coated QDs conjugated with various length of telomere probe sequences were prepared via carbodiimide chemistry and characterized. Specific detection of telomere was observed when DNA sequence was (CCCAAT)n (n = 5 or 3) probe sequence, rather than (GGGTTA)n (n = 3, 5, 8).

Recent advances in magnetic nanoparticle-based multi-modal imaging.

Magnetic nanoparticles have been extensively explored as a versatile platform for magnetic resonance imaging (MRI) contrast agents due to their strong contrast enhancement effects together with the platform capability for multiple imaging modalities. In this tutorial review, we focus on recent progress in the use of magnetic nanoparticles for MRI contrast agents and multi-mode imaging agents such as T1-T2 MRI, MRI-optical, and MRI-radioisotopes. This review also highlights emerging magnetic imaging techniques such as magnetic particle imaging (MPI), magneto-motive ultrasound imaging (MMUS), and magneto-photoacoustic imaging (MPA).

Environmental affordances: designing for family presence and involvement in patient care.

Objective: This comparative study in two ICUs examines the impact of the patient-centered unit design on family involvement, operationalized as percentages of family presence and family-patient/family-staff interaction in patient rooms.

Background: As hospitals have become more patient-centered, there has been a trend toward including a family area inside the patient area to promote family presence, support, and involvement in patient care. There is growing evidence that family members play an important role in supporting patient care, and that the physical environment affects family involvement.

Selective targeting of cellular nucleus using positively-charged quantum dots.

Developing highly selective probes for subcellular regions such as nucleus and cytoplamic organelles is of great interest for cellular imaging and high content screening analysis for biology and medicine. Cytoplasmic delivery of QDs has been well-understood, while nuclear delivery of QDs has been a challenge due to the unique structural characteristics of cell nucleus. In this study, we systematically investigated nucleus penetrating properties of small-sized ligand-exchanged QDs with either positive or negative surface charges in the similar size range of hydrodynamic diameter (7-10 nm).

Photochemical properties and shape evolution of CdSe QDs in a non-injection reaction.

Highly monodispersed CdSe quantum dots (QDs) were prepared without an injection procedure. A series of Cd salts of long chain fatty acids, including Cd-myristate (C14), Cd-palmitate (C16) and Cd-stearate (C18) was prepared, and all metallic precursors and surfactants were mixed together followed by increasing the temperature in a controlled manner. The reaction resulted in highly monodisperse and bright zinc blende QDs.

Synthesis, characterization and target protein binding of drug-conjugated quantum dots in vitro and in living cells.

Elucidation of unknown target proteins of a drug is of great importance in understanding cell biology and drug discovery. There have been extensive studies to discover and identify target proteins in the cell. Visualization of targets using drug-conjugated probes has been an important approach to gathering mechanistic information of drug action at the cellular level.

Fluorogenic quantum dot-gold nanoparticle assembly for beta secretase inhibitor screening in live cell.

We have developed a novel fluorogenic nanoprobe prepared from the assembly of CdSe/ZnS quantum dot (QD) and gold (Au) nanoparticles in which QD was conjugated with a specifically designed β-secretase (BACE1) substrate peptide, which was allowed to bind to the Ni-nitrilotriacetate (Ni-NTA) modified Au nanoparticles. This coordination-mediated binding of the QD with Au nanoparticles via Ni-NTA-histidine (His) interaction resulted in highly efficient quenching of QD fluorescence through a distance-dependent fluorescence resonance energy transfer (FRET) phenomenon. The prequenched QD-Au assembly recovered the fluorescence in the presence of the BACE1 enzyme after incubation in vitro.

Quantum dot-based screening system for discovery of g protein-coupled receptor agonists.

Cellular imaging has emerged as an important tool to unravel biological complexity and to accelerate the drug-discovery process, including cell-based screening, target identification, and mechanism of action studies. Recently, semiconductor nanoparticles known as quantum dots (QDs) have attracted great interest in cellular imaging applications due to their unique photophysical properties such as size, tunable optical property, multiplexing capability, and photostability. Herein, we show that QDs can also be applied to assay development and eventually to high-throughput/content screening (HTS/HCS) for drug discovery.

Detection of melanoma using antibody-conjugated quantum dots in a coculture model for high-throughput screening system.

We proposed an effective strategy for evaluating the targeting specificity of an antibody-conjugated quantum dot (QD) nanoprobe in a coculture system mimicking an in vivo-like tumor microenvironment in which cancer cells grow with normal cells. Analysis of the images was performed with automated confocal microscopy. We have employed a melanoma-melanocyte coculture model to assess the specific binding of QDs conjugated with melanoma antibodies.

Intracellular protein target detection by quantum dots optimized for live cell imaging.

Imaging of specific intracellular target proteins in living cells has been of great challenge and importance for understanding intracellular events and elucidating various biological phenomena. Highly photoluminescent and water-soluble semiconductor nanocrystal quantum dots (QDs) have been extensively applied to various cellular imaging applications due to the long-term photostability and the tunable narrow emission spectra with broad excitation. Despite the great success of various bioimaging and diagnostic applications, visualization of intracellular targets in live cells still has been of great challenge.

Quantum dots: a new tool for anti-malarial drug assays.

Background: Malaria infects over 300 million people every year and one of the major obstacles for the eradication of the disease is parasite's resistance to current chemotherapy, thus new drugs are urgently needed. Quantum dot (QD) is a fluorescent nanocrystal that has been in the spotlight as a robust tool for visualization of live cell processes in real time. Here, a simple and efficient method using QD to directly label Plasmodium falciparum-infected erythrocytes (iRBCs) was searched in order to use the QD as a probe in an anti-malarial drug-screening assay.

Developing a multi-systemic fall prevention model, incorporating the physical environment, the care process and technology: a systematic review.

Aims: This paper reports a review that assessed the effectiveness and characteristics of fall prevention interventions implemented in hospitals. A multi-systemic fall prevention model that establishes a practical framework was developed from the evidence.

Background: Falls occur through complex interactions between patient-related and environmental risk factors, suggesting a need for multifaceted fall prevention approaches that address both factors.

Fluorogenic assay and live cell imaging of HIV-1 protease activity using acid-stable quantum dot-peptide complex.

A novel QD-peptide complex for detecting HIV-1 protease activity was prepared from simple one step electrostatic interaction. Fluorescence recovery of the pre-quenched QD through fluorescence resonance energy transfer allowed for in vitro assay and live cell imaging of the protease activity in HIV-1 transfected cells, proving the potential for cell-based protease inhibitor screening.

Controlled stoichiometric synthesis of DNA-quantum dot conjugates using Ni-mediated coordination chemistry.

An oligonucleotide modified with Ni-nitrilotriacetate (NTA) was successfully synthesized and used for the stoichiometric functionalization of QDs. This synthetic approach allowed for the facile preparation of DNA-QD conjugates with a defined DNA/QD ratio using well-known Ni-histidine coordination chemistry. A FRET based DNA-QD nanoprobe was prepared using this method highlighting the great potential of this synthetic strategy.

Characterization and cancer cell specific binding properties of anti-EGFR antibody conjugated quantum dots.

Synthesis of biologically active antibody conjugated quantum dots (QDs) has been of great importance in cellular imaging and diagnostics. Cetuximab (or Erbitux) is the first monoclonal antibody drug which targets the epidermal growth factor receptor (EGFR) overexpressed in most cancer cells. In the present work, we investigated three different conjugation strategies to obtain the biologically functional QD-cetuximab conjugates for the tumor-specific imaging.

Compact and versatile nickel-nitrilotriacetate-modified quantum dots for protein imaging and Förster resonance energy transfer based assay.

The generation of compact quantum dots (QDs) probes is of critical importance for visualizing molecular interaction occurring in biological context, particularly when using the Förster resonance energy transfer (FRET) approach. This Article reports novel water-soluble compact CdSe/ZnS QDs prepared by ligand exchange reaction using thiolated nitrilotriacetate (NTA). The resulting NTA-QDs revealed higher stability and remarkable conjugation efficiency compared to the other QDs prepared with different ligands by using the ligand exchange method.

In situ visualization of gene expression using polymer-coated quantum-dot-DNA conjugates.

Imaging of specific mRNA targets in cells is of great importance in understanding gene expression and cell signaling processes. Subcellular localization of mRNA is known as a universal mechanism for cells to sequester specific mRNA for high production of required proteins. Various gene expressions in Drosophila cells are studied using quantum dots (QDs) and the fluorescence in situ hybridization (FISH) method.

Positively charged compact quantum Dot-DNA complexes for detection of nucleic acids.

Novel QD-DNA complexes are prepared by simple electrostatic interaction between pegylated amine-functionalized CdSe/ZnS quantum dots (QDs) and DNA. The cationic nature of the amine functionality on the QD surface allows for formation of an electrostatic complex with negatively charged DNA. The presence of polyethylene glycol (PEG5000) molecules on the QD leads to enhanced stability and decreased nonspecific adsorption of DNA on the QD surface.

A review of the research literature on evidence-based healthcare design.

Objective: This report surveys and evaluates the scientific research on evidence-based healthcare design and extracts its implications for designing better and safer hospitals.

Background: It builds on a literature review conducted by researchers in 2004.

Methods: Research teams conducted a new and more exhaustive search for rigorous empirical studies that link the design of hospital physical environments with healthcare outcomes.

Resistive-pulse DNA detection with a conical nanopore sensor.

In this paper, we describe resistive-pulse sensing of two large DNAs, a single-stranded phage DNA (7250 bases) and a double-stranded plasmid DNA (6600 base pairs), using a conically shaped nanopore in a track-etched polycarbonate membrane as the sensing element. The conically shaped nanopore had a small-diameter (tip) opening of 40 nm and a large-diameter (base) opening of 1.5 microm.

Biosensing with conically shaped nanopores and nanotubes.

In this review we consider recent results from our group that are directed towards developing "smart" synthetic nanopores that can mimic the functions of biological nanopores (transmembrane proteins). We first discuss the preparation and characterization of conical nanopores synthesized using the track-etch process. We then consider the design and function of conical nanopores that can rectify the ionic current that flows through these pores under an applied transmembrane potential.

Targeting cancer cells with DNA-assembled dendrimers: a mix and match strategy for cancer.

The unique biology of cancer requires the development of a multifunctional drug delivery system which can be efficiently manufactured to target subtle molecular alterations that distinguish a cancer cells from the many types of healthy cells found in the body. We sought to produce dendrimers conjugated to different bio-functional moieties [fluorescein (FITC) and folic acid (FA)], then link them together using complementary DNA oligonucleotides to produce clustered molecules that target cancer cells that over-express the high affinity folate receptor. This study demonstrates a unique molecular platform based on the DNA-directed assembly of dendritic polymers for the delivery of different agents to cancer cells.

Synthesis and functional evaluation of DNA-assembled polyamidoamine dendrimer clusters for cancer cell-specific targeting.

We sought to produce dendrimers conjugated to different biofunctional moieties (fluorescein [FITC] and folic acid [FA]), and then link them together using complementary DNA oligonucleotides to produce clustered molecules that target cancer cells that overexpress the high-affinity folate receptor. Amine-terminated, generation 5 polyamidoamine (G5 PAMAM) dendrimers are first partially acetylated and then conjugated with FITC or FA, followed by the covalent attachment of complementary, 5'-phosphate-modified 34-base-long oligonucleotides. Hybridization of these oligonucleotide conjugates led to the self-assembly of the FITC- and FA-conjugated dendrimers.