Publications by authors named "Schein P"

In this work, we introduce HI-Light, a surface-engineered glass-waveguide-based "shell-and-tube" type photothermal reactor which is both scalable in diameter and length. We examine the effect of temperature, light irradiation, and residence time on its photo-thermocatalytic performance for CO hydrogenation to form CO, with a cubic phase defect-laden indium oxide, In2O3-x(OH)y, catalyst. We demonstrate the light enhancement effect under a variety of reaction conditions.

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Living cells employ various defence mechanisms against reactive oxygen species and free radicals. Besides protecting enzymes such as superoxide dismutase, catalase and peroxidase, non-enzymatic antioxidant molecules also play an important role as radical scavengers. Within bacteria the amino acid derivative ectoine (2-methyl-3,4,5,6-tetrahydropyrimidine-4-carboxylate) is the most abundant compatible solute and stress protectant.

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The past decade has been a time of great change for US physicians. Many physicians feel that the care delivery system has become a barrier to providing high-quality care rather than facilitating it. Although physician distress and some of the contributing factors are now widely recognized, much of the distress physicians are experiencing is related to insidious issues affecting the cultures of our profession, our health care organizations, and the health care delivery system.

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The behavior of a nanoparticle in solution depends strongly on the particle's physical and chemical characteristics, most notably the particle size and the surface properties. Accurately characterizing these properties is critical for quality control in a wide variety of industries. To understand a complex and polydisperse nanoparticle suspension, however, ensemble averaging is not sufficient, and there is a great need for direct measurements of size and surface properties at the individual nanoparticle level.

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Here we measure the hindered diffusion of an optically confined nanoparticle in the direction normal to a surface, and we use this to determine the particle-surface interaction profile in terms of the absolute height. These studies are performed using the evanescent field of an optically excited single-mode silicon nitride waveguide, where the particle is confined in a height-dependent potential energy well generated from the balance of optical gradient and surface forces. Using a high-speed cmos camera, we demonstrate the ability to capture the short time-scale diffusion dominated motion for 800-nm-diam polystyrene particles, with measurement times of only a few seconds per particle.

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Nanoparticles are quickly becoming commonplace in many commercial and industrial products, ranging from cosmetics to pharmaceuticals to medical diagnostics. Predicting the stability of the engineered nanoparticles within these products remains an important and difficult challenge. Here we describe our techniques for measuring the mechanical interactions between nanoparticles and surfaces using near-field light scattering.

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Biomolecular interactions, such as antibody-antigen binding, are fundamental to many biological processes. At present, most techniques for analyzing these interactions require immobilizing one or both of the interacting molecules on an assay plate or a sensor surface. This is convenient experimentally but can constrain the natural binding affinity and capacity of the molecules, resulting in data that can deviate from the natural free-solution behavior.

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Direct measurements of particle-surface interactions are important for characterizing the stability and behavior of colloidal and nanoparticle suspensions. Current techniques are limited in their ability to measure pico-Newton scale interaction forces on submicrometer particles due to signal detection limits and thermal noise. Here we present a new technique for making measurements in this regime, which we refer to as nanophotonic force microscopy.

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Filamin C (FLNc) and Xin actin-binding repeat-containing proteins (XIRPs) are multi-adaptor proteins that are mainly expressed in cardiac and skeletal muscles and which play important roles in the assembly and repair of myofibrils and their attachment to the membrane. We identified the dystrophin-binding protein aciculin (also known as phosphoglucomutase-like protein 5, PGM5) as a new interaction partner of FLNc and Xin. All three proteins colocalized at intercalated discs of cardiac muscle and myotendinous junctions of skeletal muscle, whereas FLNc and aciculin also colocalized in mature Z-discs.

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Article Synopsis
  • The vasculature in the adult brain influences how neural stem cells behave by supplying essential factors, which is crucial for neurogenesis and cognitive function.
  • Age-related decreases in blood flow and neural stem cell numbers contribute to declines in neurogenesis and cognitive abilities.
  • Young blood factors can improve brain blood vessels and neurogenesis, with GDF11 showing promise for enhancing these effects, potentially leading to new treatments for age-related brain diseases.
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Amyotrophic lateral sclerosis (ALS) is a rapidly progressing neurodegenerative disease, characterized by motor neuron (MN) death, for which there are no truly effective treatments. Here, we describe a new small molecule survival screen carried out using MNs from both wild-type and mutant SOD1 mouse embryonic stem cells. Among the hits we found, kenpaullone had a particularly impressive ability to prolong the healthy survival of both types of MNs that can be attributed to its dual inhibition of GSK-3 and HGK kinases.

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Introduction: Experimental and clinical data show that the oral bisphosphonate clodronate (Bonefos) can inhibit tumor-induced osteoclastic bone resorption. This randomized, double-blind, placebo-controlled, multicenter trial was designed to determine if the addition of oral clodronate to standard treatment for primary operable breast cancer could reduce the subsequent occurrence of bone metastases and thereby improve overall survival.

Methods: 1,069 patients with primary operable stage I-III breast cancer were randomized to receive oral clodronate (1,600 mg/day) or placebo for 2 years, in conjunction with standard treatment for primary breast cancer including surgery, radiotherapy, adjuvant chemotherapy, and/or tamoxifen.

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Objective: The aim of this study was to describe the interaction pattern formed between dentin and resin on cavities prepared with an erbium laser (Er:YAG). The morphological aspect of the irradiated dentin after acid etching was also observed.

Methods: Ten dentin disks were obtained from fresh extracted third molars.

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Purpose: A phase II study to evaluate the response rate and toxicities of a trimetrexate, fluorouracil (5FU), and leucovorin regimen in patients with advanced incurable colorectal cancer.

Patients And Methods: Thirty-six patients with unresectable or metastatic colorectal cancer who had not been treated for advanced disease received the following chemotherapy regimen weekly for six courses every 8 weeks: trimetrexate 110 mg/m2 intravenously (I.V.

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One of the main obstacles for the use of high-dose chemotherapy with autologous hematopoietic progenitor cell support in the treatment of malignancies is the possibility of reinfusing clonogenic tumor cells with the hematopoietic graft. Purging of the graft with chemicals can reduce the number of tumor cells but can also damage the normal hematopoietic progenitors. Preclinical studies showed that the phosphorylated sulfhydryl compound amifostine (WR-2721) can protect normal hematopoietic progenitors from damage from alkylating agents.

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Reducing agents such as glutathione (GSH), glutathione ester (GSE), and N-acetylcysteine (NAC) have been shown to suppress the induction of HIV expression in chronically infected cells stimulated by cytokines. We present data which show the effects of the organic thiophosphate WR-151327 on the expression of latent HIV in U1 cells. The chronically infected promonocytic cell line U1 constitutively expresses low levels of HIV that can be increased by 13-phorbol 12-myristate acetate (PMA), tumor necrosis factor alpha (TNF-alpha), and granulocyte/monocyte colony-stimulating factor (GM-CSF).

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Clinical trials are in progress to evaluate radio- and chemoprotection by the aminothiol 2-[(3-aminopropyl)amino]ethanethiol-dihydrogen phosphate ester (WR-2721; amifostine). Phase II and III clinical studies have demonstrated that i.v.

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The use of mitomycin for metastatic colorectal cancer has been limited by mitomycin's myelosuppressive potential. The objective of this randomized study was to determine whether WR-2721 would decrease the hematologic toxicity of mitomycin in patients with colorectal cancer resistant to fluorouracil-based therapy. Ninety-seven patients with refractory colorectal cancer were randomized to receive either mitomycin 20 mg/m2 only or the same dose of mitomycin after pretreatment with WR-2721, 910 mg/m2.

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Amifostine (US Bioscience, West Conshohocken, PA; Ethyol, WR-2721), a phosphorylated thiol developed by the United States Army as a protective agent for military personnel in the event of nuclear warfare, has shown protection of normal tissues from the cytotoxic effects of therapeutic radiation and chemotherapy with preservation of cytotoxic effects on the tumor. The basis of this selective protection derives from the relatively rapid uptake and anabolism of Amifostine into normal tissues and minimal, slower uptake into tumor tissue. Preclinical investigations have demonstrated protection of bone marrow stem cells from the toxic effects of radiation and chemotherapy.

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Hexamethylmelamine has been recognized as having useful single-agent activity for the treatment of ovarian cancer for the past 25 years, with some patients surviving disease-free for periods in excess of 12 years. Data from recently analysed and mature trials demonstrate that the addition of hexamethylmelamine to first-line combination chemotherapy results in significant improvements in survival compared to what is achieved with regimens of cisplatin and cyclophosphamide with or without doxorubicin.

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Hexamethylmelamine (altretamine, HMM) 260 mg/m2/day p.o. for 14 days followed by a 14-day drug-free interval was administered to 52 outpatients with advanced ovarian cancer who had previously been treated with chemotherapy.

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