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Find video protocols related to scientific articles indexed in Pubmed.
Dual-Layer Surface Coating of PLGA-Based Nanoparticles Provides Slow-Release Drug Delivery To Achieve Metronomic Therapy in a Paclitaxel-Resistant Murine Ovarian Cancer Model.
Biomacromolecules
PUBLISHED: 10-07-2014
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Development of drug resistance is a central challenge to the treatment of ovarian cancer. Metronomic chemotherapy decreases the extent of drug-free periods, thereby hindering development of drug resistance. Intraperitoneal chemotherapy allows for treatment of tumors confined within the peritoneum, but achieving sustained tumor-localized chemotherapy remains difficult. We hypothesized that modulating the surface properties of poly(lactic-co-glycolic acid) (PLGA)-based nanoparticles could enhance their drug retention ability and extend their release profile, thereby enabling metronomic, localized chemotherapy in vivo. Paclitaxel was encapsulated in particles coated with a layer of polydopamine and a subsequent layer of poly(ethylene glycol) (PEG). These particles achieved a 3.8-fold higher loading content compared to that of nanoparticles formulated from linear PLGA-PEG copolymers. In vitro release kinetic studies and in vivo drug distribution profiles demonstrate sustained release of paclitaxel. Although free drug conferred no survival advantage, low-dose intraperitoneal administration of paclitaxel-laden surface-coated nanoparticles to drug-resistant ovarian tumor-bearing mice resulted in significant survival benefits in the absence of any apparent systemic toxicity.
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Digital video technology and production 101: lights, camera, action.
Health Promot Pract
PUBLISHED: 08-26-2014
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Videos are powerful tools for enhancing the reach and effectiveness of health promotion programs. They can be used for program promotion and recruitment, for training program implementation staff/volunteers, and as elements of an intervention. Although certain brief videos may be produced without technical assistance, others often require collaboration and contracting with professional videographers. To get practitioners started and to facilitate interactions with professional videographers, this Tool includes a guide to the jargon of video production and suggestions for how to integrate videos into health education and promotion work. For each type of video, production principles and issues to consider when working with a professional videographer are provided. The Tool also includes links to examples in each category of video applications to health promotion.
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Colonic mucosal Fatty Acid synthase as an early biomarker for colorectal neoplasia: modulation by obesity and gender.
Cancer Epidemiol. Biomarkers Prev.
PUBLISHED: 08-25-2014
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We have previously reported that colonic pericryptal microvascular blood flow is augmented in the premalignant colonic epithelium, highlighting the increased metabolic demand of the proliferative epithelium as a marker of field carcinogenesis. However, its molecular basis is unexplored. In this study, we assessed the expression of a regulator of the "lipogenic switch," fatty acid synthase (FASN), in early colon carcinogenesis for its potential biomarker utility for concurrent neoplasia.
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Decreased bone mineral density in young adult IgE-mediated cow's milk-allergic patients.
J. Allergy Clin. Immunol.
PUBLISHED: 06-25-2014
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IgE-mediated cow's milk-allergic (IgE-CMA) patients provide a valuable model for studying the relationship between dairy intake and bone mineral density (BMD) because they are unable to consume even minor amounts of dairy foods.
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Evaluation of periodontal disease and oral inflammatory load in adults with special needs using oral neutrophil quantification.
Spec Care Dentist
PUBLISHED: 06-24-2014
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The purpose of this study was to validate and assess the feasibility of using an assay of oral neutrophils to measure periodontal inflammation in uncooperative adults with special needs. Conventional periodontal measurements and neutrophil counts obtained from oral swabs were performed on patients having dental care under general anesthesia (GA) and at subsequent recall. Forty-nine patients were assessed under GA and 30 (61%) returned for follow-up. A high prevalence of gingival inflammation was found at baseline and oral neutrophil levels positively correlated with traditional periodontal parameters (p < 0.05). Neutrophils were acquired using swabs for 100% of patients examined at recall and a significant reduction in oral inflammatory load was noted after a single treatment session (p < 0.05), despite the persistence of poor oral hygiene and prolonged recall intervals. This study demonstrates that oral neutrophil quantification may serve as a novel and standardized method for clinical assessment of periodontal diseases in people with special needs.
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A spatially nonselective baseline signal in parietal cortex reflects the probability of a monkey's success on the current trial.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 06-02-2014
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We recorded the activity of neurons in the lateral intraparietal area of two monkeys while they performed two similar visual search tasks, one difficult, one easy. Each task began with a period of fixation followed by an array consisting of a single capital T and a number of lowercase t's. The monkey had to find the capital T and report its orientation, upright or inverted, with a hand movement. In the easy task the monkey could explore the array with saccades. In the difficult task the monkey had to continue fixating and find the capital T in the visual periphery. The baseline activity measured during the fixation period, at a time in which the monkey could not know if the impending task would be difficult or easy or where the target would appear, predicted the monkey's probability of success or failure on the task. The baseline activity correlated inversely with the monkey's recent history of success and directly with the intensity of the response to the search array on the current trial. The baseline activity was unrelated to the monkey's spatial locus of attention as determined by the location of the cue in a cued visual reaction time task. We suggest that rather than merely reflecting the noise in the system, the baseline signal reflects the cortical manifestation of modulatory state, motivational, or arousal pathways, which determine the efficiency of cortical sensorimotor processing and the quality of the monkey's performance.
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Natural history of food protein-induced enterocolitis syndrome.
Curr Opin Allergy Clin Immunol
PUBLISHED: 04-02-2014
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Because of the paucity of reports and variability in the diagnostic criteria utilized, little is known regarding the natural outcome of patients with food protein-induced enterocolitis syndrome (FPIES). Data extracted from referenced manuscripts, as well as allergists' unpublished observations from across the globe, were used to form a cohesive opinion regarding its natural outcome.
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Targeting myeloid cells using nanoparticles to improve cancer immunotherapy.
Adv. Drug Deliv. Rev.
PUBLISHED: 03-14-2014
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While nanoparticles have traditionally been used to deliver cytotoxic drugs directly to tumors to induce cancer cell death, emerging data suggest that nanoparticles are likely to generate a larger impact on oncology through the delivery of agents that can stimulate antitumor immunity. Tumor-targeted nanocarriers have generally been used to localize chemotherapeutics to tumors and thus decrease off-target toxicity while enhancing efficacy. Challengingly, tumor heterogeneity and evolution render tumor-intrinsic approaches likely to succumb to relapse. The immune system offers exquisite specificity, cytocidal potency, and long-term activity that leverage an adaptive memory response. For this reason, the ability to manipulate immune cell specificity and function would be desirable, and nanoparticles represent an exciting means by which to perform such manipulation. Dendritic cells and tumor-associated macrophages are cells of the myeloid lineage that function as natural phagocytes, so they naturally take up nanoparticles. Dendritic cells direct the specificity and potency of cellular immune responses that can be targeted for cancer vaccines. Herein, we discuss the specific criteria needed for efficient vaccine design, including but not limited to the route of administration, size, morphology, surface charge, targeting ligands, and nanoparticle composition. In contrast, tumor-associated macrophages are critical mediators of immunosuppression whose trans-migratory abilities can be exploited to localize therapeutics to the tumor core and which can be directly targeted for elimination or for repolarization to a tumor suppressive phenotype. It is likely that a combination of targeting dendritic cells to stimulate antitumor immunity and tumor-associated macrophages to reduce immune suppression will impart significant benefits and result in durable antitumor responses.
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Enhanced medial prefrontal-default mode network functional connectivity in chronic pain and its association with pain rumination.
J. Neurosci.
PUBLISHED: 03-14-2014
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Rumination is a form of thought characterized by repetitive focus on discomforting emotions or stimuli. In chronic pain disorders, rumination can impede treatment efficacy. The brain mechanisms underlying rumination about chronic pain are not understood. Interestingly, a link between rumination and functional connectivity (FC) of the brain's default mode network (DMN) has been identified within the context of mood disorders. We, and others, have also found DMN dysfunction in chronic pain populations. The medial prefrontal cortex (mPFC) is a key node of the DMN that is anatomically connected with the descending pain modulatory system. Therefore, we tested the hypothesis that in patients with chronic pain, the mPFC exhibits abnormal FC related to the patient's degree of rumination about their pain. Seventeen patients with idiopathic temporomandibular disorder (TMD) and 17 age- and sex-matched healthy controls underwent resting state functional MRI, and rumination about pain was assessed through the rumination subscale of the Pain Catastrophizing Scale. Compared with healthy controls, we found that TMD patients exhibited enhanced mPFC FC with other DMN regions, including the posterior cingulate cortex (PCC)/precuneus (PCu) and retrosplenial cortex. We also found that individual differences in pain rumination in the chronic pain patients (but not in healthy controls) were positively correlated to mPFC FC with the PCC/PCu, retrosplenial cortex, medial thalamus, and periaqueductal/periventricular gray. These data implicate communication within the DMN and of the DMN with the descending modulatory system as a mechanism underlying the degree to which patients ruminate about their chronic pain.
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Greatwall-phosphorylated Endosulfine is both an inhibitor and a substrate of PP2A-B55 heterotrimers.
Elife
PUBLISHED: 03-13-2014
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During M phase, Endosulfine (Endos) family proteins are phosphorylated by Greatwall kinase (Gwl), and the resultant pEndos inhibits the phosphatase PP2A-B55, which would otherwise prematurely reverse many CDK-driven phosphorylations. We show here that PP2A-B55 is the enzyme responsible for dephosphorylating pEndos during M phase exit. The kinetic parameters for PP2A-B55's action on pEndos are orders of magnitude lower than those for CDK-phosphorylated substrates, suggesting a simple model for PP2A-B55 regulation that we call inhibition by unfair competition. As the name suggests, during M phase PP2A-B55's attention is diverted to pEndos, which binds much more avidly and is dephosphorylated more slowly than other substrates. When Gwl is inactivated during the M phase-to-interphase transition, the dynamic balance changes: pEndos dephosphorylated by PP2A-B55 cannot be replaced, so the phosphatase can refocus its attention on CDK-phosphorylated substrates. This mechanism explains simultaneously how PP2A-B55 and Gwl together regulate pEndos, and how pEndos controls PP2A-B55. DOI: http://dx.doi.org/10.7554/eLife.01695.001.
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Nanoscale changes in chromatin organization represent the initial steps of tumorigenesis: a transmission electron microscopy study.
BMC Cancer
PUBLISHED: 03-05-2014
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Nuclear alterations are a well-known manifestation of cancer. However, little is known about the early, microscopically-undetectable stages of malignant transformation. Based on the phenomenon of field cancerization, the tissue in the field of a tumor can be used to identify and study the initiating events of carcinogenesis. Morphological changes in nuclear organization have been implicated in the field of colorectal cancer (CRC), and we hypothesize that characterization of chromatin alterations in the early stages of CRC will provide insight into cancer progression, as well as serve as a biomarker for early detection, risk stratification and prevention.
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Oral immunotherapy for peanut allergy: multipractice experience with epinephrine-treated reactions.
J Allergy Clin Immunol Pract
PUBLISHED: 02-26-2014
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Peanut allergy creates the risk of life-threatening anaphylaxis that can disrupt psychosocial development and family life. The avoidance management strategy often fails to prevent anaphylaxis and may contribute to social dysfunction. Peanut oral immunotherapy may address these problems, but there are safety concerns regarding implementation in clinical practice.
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Isolated perioperative hypertension: clinical implications & contemporary treatment strategies.
Curr Hypertens Rev
PUBLISHED: 02-18-2014
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Perioperative hypertension has been shown to be a risk factor for the development of perioperative morbidity and mortality. The time spent outside acceptable blood pressure ranges, in a state of hypertension or hypotension, is correlated with the incidence of stroke, acute coronary syndrome, renal dysfunction, and death. The ideal perioperative treatment of hypertension would include an easily titratable agent, with fast onset and offset and minimal side effects. Several medication classes are routinely used in the operating room, including, but not limited to, beta-blockers, calcium channel blockers, nitrates, and angiotensin-converting enzyme (ACE) inhibitors.Proper treatment of chronic hypertension and continuation of chronic anti-hypertensive medications in the perioperative period has been demonstrated to improve patient outcomes. This review article will outline the importance of perioperative blood pressure management, the treatment pitfalls, and the novel medications being used in the perioperative setting.
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Spatially resolved optical and ultrastructural properties of colorectal and pancreatic field carcinogenesis observed by inverse spectroscopic optical coherence tomography.
J Biomed Opt
PUBLISHED: 02-17-2014
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Field carcinogenesis is the initial stage of cancer progression. Understanding field carcinogenesis is valuable for both cancer biology and clinical medicine. Here, we used inverse spectroscopic optical coherence tomography to study colorectal cancer (CRC) and pancreatic cancer (PC) field carcinogenesis. Depth-resolved optical and ultrastructural properties of the mucosa were quantified from histologically normal rectal biopsies from patients with and without colon adenomas (n=85) as well as from histologically normal peri-ampullary duodenal biopsies from patients with and without PC (n=22). Changes in the epithelium and stroma in CRC field carcinogenesis were separately quantified. In both compartments, optical and ultra-structural alterations were consistent. Optical alterations included lower backscattering (?b) and reduced scattering (?s') coefficients and higher anisotropy factor g. Ultrastructurally pronounced alterations were observed at length scales up to ?450??nm, with the shape of the mass density correlation function having a higher shape factor D, thus implying a shift to larger length scales. Similar alterations were found in the PC field carcinogenesis despite the difference in genetic pathways and etiologies. We further verified that the chromatin clumping in epithelial cells and collagen cross-linking caused D to increase in vitro and could be among the mechanisms responsible for the observed changes in epithelium and stroma, respectively.
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Extrafoveal preview benefit during free-viewing visual search in the monkey.
J Vis
PUBLISHED: 01-10-2014
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Previous studies have shown that subjects require less time to process a stimulus at the fovea after a saccade if they have viewed the same stimulus in the periphery immediately prior to the saccade. This extrafoveal preview benefit indicates that information about the visual form of an extrafoveally viewed stimulus can be transferred across a saccade. Here, we extend these findings by demonstrating and characterizing a similar extrafoveal preview benefit in monkeys during a free-viewing visual search task. We trained two monkeys to report the orientation of a target among distractors by releasing one of two bars with their hand; monkeys were free to move their eyes during the task. Both monkeys took less time to indicate the orientation of the target after foveating it, when the target lay closer to the fovea during the previous fixation. An extrafoveal preview benefit emerged even if there was more than one intervening saccade between the preview and the target fixation, indicating that information about target identity could be transferred across more than one saccade and could be obtained even if the search target was not the goal of the next saccade. An extrafoveal preview benefit was also found for distractor stimuli. These results aid future physiological investigations of the extrafoveal preview benefit.
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A single subset of dendritic cells controls the cytokine bias of natural killer T cell responses to diverse glycolipid antigens.
Immunity
PUBLISHED: 01-09-2014
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Many hematopoietic cell types express CD1d and are capable of presenting glycolipid antigens to invariant natural killer T cells (iNKT cells). However, the question of which cells are the principal presenters of glycolipid antigens in vivo remains controversial, and it has been suggested that this might vary depending on the structure of a particular glycolipid antigen. Here we have shown that a single type of cell, the CD8?(+) DEC-205(+) dendritic cell, was mainly responsible for capturing and presenting a variety of different glycolipid antigens, including multiple forms of ?-galactosylceramide that stimulate widely divergent cytokine responses. After glycolipid presentation, these dendritic cells rapidly altered their expression of various costimulatory and coinhibitory molecules in a manner that was dependent on the structure of the antigen. These findings show flexibility in the outcome of two-way communication between CD8?(+) dendritic cells and iNKT cells, providing a mechanism for biasing toward either proinflammatory or anti-inflammatory responses.
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Silencing HoxA1 by intraductal injection of siRNA lipidoid nanoparticles prevents mammary tumor progression in mice.
Sci Transl Med
PUBLISHED: 01-03-2014
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With advances in screening, the incidence of detection of premalignant breast lesions has increased in recent decades; however, treatment options remain limited to surveillance or surgical removal by lumpectomy or mastectomy. We hypothesized that disease progression could be blocked by RNA interference (RNAi) therapy and set out to develop a targeted therapeutic delivery strategy. Using computational gene network modeling, we identified HoxA1 as a putative driver of early mammary cancer progression in transgenic C3(1)-SV40TAg mice. Silencing this gene in cultured mouse or human mammary tumor spheroids resulted in increased acinar lumen formation, reduced tumor cell proliferation, and restoration of normal epithelial polarization. When the HoxA1 gene was silenced in vivo via intraductal delivery of nanoparticle-formulated small interfering RNA (siRNA) through the nipple of transgenic mice with early-stage disease, mammary epithelial cell proliferation rates were suppressed, loss of estrogen and progesterone receptor expression was prevented, and tumor incidence was reduced by 75%. This approach that leverages new advances in systems biology and nanotechnology offers a novel noninvasive strategy to block breast cancer progression through targeted silencing of critical genes directly within the mammary epithelium.
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Bacterial community composition of chronic periodontitis and novel oral sampling sites for detecting disease indicators.
Microbiome
PUBLISHED: 01-01-2014
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Periodontitis is an infectious and inflammatory disease of polymicrobial etiology that can lead to the destruction of bones and tissues that support the teeth. The management of chronic periodontitis (CP) relies heavily on elimination or at least control of known pathogenic consortia associated with the disease. Until now, microbial plaque obtained from the subgingival (SubG) sites has been the primary focus for bacterial community analysis using deep sequencing. In addition to the use of SubG plaque, here, we investigated whether plaque obtained from supragingival (SupG) and tongue dorsum sites can serve as alternatives for monitoring CP-associated bacterial biomarkers.
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Spatial representation and cognitive modulation of response variability in the lateral intraparietal area priority map.
J. Neurosci.
PUBLISHED: 10-11-2013
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The lateral intraparietal area (LIP) in the macaque contains a priority-based representation of the visual scene. We previously showed that the mean spike rate of LIP neurons is strongly influenced by spatially wide-ranging surround suppression in a manner that effectively sharpens the priority map. Reducing response variability can also improve the precision of LIPs priority map. We show that when a monkey plans a visually guided delayed saccade with an intervening distractor, variability (measured by the Fano factor) decreases both for neurons representing the saccade goal and for neurons representing the broad spatial surround. The reduction in Fano factor is maximal for neurons representing the saccade goal and steadily decreases for neurons representing more distant locations. LIP Fano factor changes are behaviorally significant: increasing expected reward leads to lower variability for the LIP representation of both the target and distractor locations, and trials with shorter latency saccades are associated with lower Fano factors in neurons representing the surround. Thus, the LIP Fano factor reflects both stimulus and behavioral engagement. Quantitative modeling shows that the interaction between mean spike count and target-receptive field (RF) distance in the surround during the predistractor epoch is multiplicative: the Fano factor increases more steeply with mean spike count further away from the RF. A negative-binomial model for LIP spike counts captures these findings quantitatively, suggests underlying mechanisms based on trial-by-trial variations in mean spike rate or burst-firing patterns, and potentially provides a principled framework to account simultaneously for the previously observed unsystematic relationships between spike rate and variability in different brain areas.
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Nanoscale markers of esophageal field carcinogenesis: potential implications for esophageal cancer screening.
Endoscopy
PUBLISHED: 09-09-2013
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Background and study aims: Esophageal adenocarcinoma (EAC) has a dismal prognosis unless treated early or prevented at the precursor stage of Barretts esophagus-associated dysplasia. However, some patients with cancer or dysplastic Barretts esophagus (DBE) may not be captured by current screening and surveillance programs. Additional screening techniques are needed to determine who would benefit from endoscopic screening or surveillance. Partial wave spectroscopy (PWS) microscopy (also known as nanocytology) measures the disorder strength (Ld ), a statistic that characterizes the spatial distribution of the intracellular mass at the nanoscale level and thus provides insights into the cell nanoscale architecture beyond that which is revealed by conventional microscopy. The aim of the present study was to compare the disorder strength measured by PWS in normal squamous epithelium in the proximal esophagus to determine whether nanoscale architectural differences are detectable in the field area of EAC and Barretts esophagus. Methods: During endoscopy, proximal esophageal squamous cells were obtained by brushings and were fixed in alcohol and stained with standard hematoxylin and Cyto-Stain. The disorder strength of these sampled squamous cells was determined by PWS. Results: A total of 75 patient samples were analyzed, 15 of which were pathologically confirmed as EAC, 13 were DBE, and 15 were non-dysplastic Barretts esophagus; 32 of the patients, most of whom had reflux symptoms, acted as controls. The mean disorder strength per patient in cytologically normal squamous cells in the proximal esophagus of patients with EAC was 1.79-times higher than that of controls (P?
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Clinical predictors for favorable outcomes in an oral immunotherapy program for IgE-mediated cows milk allergy.
Ann. Allergy Asthma Immunol.
PUBLISHED: 06-20-2013
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Avoidance strategies in patients with cows milk allergy occasionally fail to protect these patients from inadvertent exposures, leading to life-threatening reactions.
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Ultrastructural alterations in field carcinogenesis measured by enhanced backscattering spectroscopy.
J Biomed Opt
PUBLISHED: 06-12-2013
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Optical characterization of biological tissue in field carcinogenesis offers a method with which to study the mechanisms behind early cancer development and the potential to perform clinical diagnosis. Previously, low-coherence enhanced backscattering spectroscopy (LEBS) has demonstrated the ability to discriminate between normal and diseased organs based on measurements of histologically normal-appearing tissue in the field of colorectal (CRC) and pancreatic (PC) cancers. Here, we implement the more comprehensive enhanced backscattering (EBS) spectroscopy to better understand the structural and optical changes which lead to the previous findings. EBS provides high-resolution measurement of the spatial reflectance profile P(rs) between 30 microns and 2.7 mm, where information about nanoscale mass density fluctuations in the mucosa can be quantified. A demonstration of the length-scales at which P(rs) is optimally altered in CRC and PC field carcinogenesis is given and subsequently these changes are related to the tissues structural composition. Three main conclusions are made. First, the most significant changes in P(rs) occur at short length-scales corresponding to the superficial mucosal layer. Second, these changes are predominantly attributable to a reduction in the presence of subdiffractional structures. Third, similar trends are seen for both cancer types, suggesting a common progression of structural alterations in each.
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Role of lysosome rupture in controlling Nlrp3 signaling and necrotic cell death.
Cell Cycle
PUBLISHED: 05-20-2013
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The Nod-like receptor, Nlrp3, has been linked to inflammatory diseases and adjuvant-mediated immune responses. A wide array of structurally diverse agents does not interact directly with Nlrp3, but is thought to activate the Nlrp3 inflammasome by inducing a common upstream signal, such as lysosome rupture. To test the connection between lysosome integrity and Nlrp3 signaling, we analyzed inflammasome activation following stimulation of murine macrophages with lysosome-destabilizing agents and pyroptosis inducers. Here we provide evidence that lysosomal rupture and the corresponding release of lysosomal hydrolases is an early event in macrophages exposed to the lysosome-destabilizing adjuvants LLOMe and alum. Lysosome rupture preceded cell death induction mediated by these agents and was associated with the degradation of low-molecular weight proteins, including the inflammasome component caspase-1. Proteolysis of caspase-1 was controlled by specific cathepsins, but was independent of autocatalytic processes and Nlrp3 signaling. Consistent with these findings, lysosome-disrupting agents triggered only minimal caspase-1 activation and failed to cause caspase-1-dependent cell death (pyroptosis), generally associated with Nlrp3 signaling. In contrast, lysosome rupture was a late event in macrophages exposed to prototypical pyroptosis inducers. These agents triggered extensive Nlrp3 signaling prior to lysosome rupture with only minimal impact on the cellular proteome. Taken together, our findings suggest that lysosome impairment triggers a cascade of events culminating in cell death but is not crucial for Nlrp3 signaling. The significant differences observed between lysosome-disrupting agents and pyroptosis inducers might explain the distinct immunologic responses associated with these compounds.
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Mislabelled cows milk allergy in infants: a prospective cohort study.
Arch. Dis. Child.
PUBLISHED: 03-26-2013
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Although cows milk allergy (CMA) is one of the most common food allergies, mislabelling non-allergic infants as being allergic to cows milk is more common. Despite this, characteristics of families and infants with mislabelled CMA are lacking.
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The lateral intraparietal area codes the location of saccade targets and not the dimension of the saccades that will be made to acquire them.
J. Neurophysiol.
PUBLISHED: 03-06-2013
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Activity in the lateral intraparietal area (LIP) represents a priority map that can be used to direct attention and guide eye movements. However, it is not known whether this activity represents the location of saccade targets or the actual eye movement made to acquire them. We recorded single neurons from rhesus macaques (Macaca mulatta) while they performed memory-guided delayed saccades to characterize the response profiles of LIP cells. We then separated the saccade target from the saccade end point by saccadic adaptation, a method that induces a change in the gain of the oculomotor system. We plotted LIP activity for all three epochs of the memory-guided delayed-response task (visual, delay period, and presaccadic responses) as a function of target location and saccade end point. We found that under saccadic adaptation the response profile for all three epochs was unchanged as a function of target location. We conclude that neurons in LIP reliably represent the locations of saccade targets, not the amplitude of the saccade required to acquire those targets. Although LIP transmits target information to the motor system, that information represents the location of the target and not the amplitude of the saccade that the monkey will make.
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Prevention of orthopaedic implant infection in patients undergoing dental procedures.
J Am Acad Orthop Surg
PUBLISHED: 03-05-2013
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The Prevention of Orthopaedic Implant Infection in Patients Undergoing Dental Procedures evidence-based clinical practice guideline was codeveloped by the American Academy of Orthopaedic Surgeons (AAOS) and the American Dental Association. This guideline replaces the previous AAOS Information Statement, "Antibiotic Prophylaxis in Bacteremia in Patients With Joint Replacement," published in 2009. Based on the best current evidence and a systematic review of published studies, three recommendations have been created to guide clinical practice in the prevention of orthopaedic implant infections in patients undergoing dental procedures. The first recommendation is graded as Limited; this recommendation proposes that the practitioner consider changing the long-standing practice of routinely prescribing prophylactic antibiotic for patients with orthopaedic implants who undergo dental procedures. The second, graded as Inconclusive, addresses the use of oral topical antimicrobials in the prevention of periprosthetic joint infections. The third recommendation, a Consensus statement, addresses the maintenance of good oral hygiene.
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Transcription Factor/microRNA Axis Blocks Melanoma Invasion Program by miR-211 Targeting NUAK1.
J. Invest. Dermatol.
PUBLISHED: 02-13-2013
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Melanoma is one of the deadliest human cancers, responsible for approximately 80% of skin cancer mortalities. The aggressiveness of melanoma is due to its capacity to proliferate and rapidly invade surrounding tissues, leading to metastases. A recent model suggests melanoma progresses by reversibly switching between proliferation and invasion transcriptional signatures. Recent studies show that cancer cells are more sensitive to microRNA (miRNA) perturbation than are non-cancer cells; however, the roles of miRNAs in melanoma plasticity remain unexplored. Here, we use the gene expression profiles of melanoma and normal melanocytes to characterize the transcription factor-miRNA relationship that modulates the proliferative and invasive programs of melanoma. We identified two sets of miRNAs that likely regulate these programs. Interestingly, one of the miRNAs involved in melanoma invasion is miR-211, a known target of the master regulator microphthalmia-associated transcription factor (MITF). We demonstrate that miR-211 contributes to melanoma adhesion by directly targeting a gene, NUAK1. Inhibition of miR-211 increases NUAK1 expression and decreases melanoma adhesion, whereas upregulation of miR-211 restores adhesion through NUAK1 repression. This study defines the MITF/miR-211 axis that inhibits the invasive program by blocking adhesion. Furthermore, we have identified NUAK1 as a potential target for the treatment of metastatic melanoma.Journal of Investigative Dermatology advance online publication, 19 September 2013; doi:10.1038/jid.2013.340.
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Biotargeted nanomedicines for cancer: six tenets before you begin.
Nanomedicine (Lond)
PUBLISHED: 02-12-2013
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Biotargeted nanomedicines have captured the attention of academic and industrial scientists who have been motivated by the theoretical possibilities of the magic bullet that was first conceptualized by Paul Ehrlich at the beginning of the 20th century. The Biotargeting Working Group, consisting of more than 50 pharmaceutical scientists, engineers, biologists and clinicians, has been formed as part of the National Cancer Institutes Alliance for Nanotechnology in Cancer to harness collective wisdom in order to tackle conceptual and practical challenges in developing biotargeted nanomedicines for cancer. In modern science and medicine, it is impossible for any individual to be an expert in every aspect of biology, chemistry, materials science, pharmaceutics, toxicology, chemical engineering, imaging, physiology, oncology and regulatory affairs. Drawing on the expertise of leaders from each of these disciplines, this commentary highlights six tenets of biotargeted cancer nanomedicines in order to enable the translation of basic science into clinical practice.
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Skin closure after trauma laparotomy in high-risk patients: opening opportunities for improvement.
J Trauma Acute Care Surg
PUBLISHED: 01-29-2013
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Although many surgeons leave laparotomy incisions open after colon injury to prevent surgical site infection (SSI), other injured patient subsets are also at risk. We hypothesized that leaving trauma laparotomy skin incisions open in high-risk patients with any enteric injury or requiring damage control laparotomy (DCL) would not affect superficial SSI and fascial dehiscence rates.
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siRNA delivery for the treatment of ovarian cancer.
Methods
PUBLISHED: 01-23-2013
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Short interfering RNAs (siRNAs) mediate the catalytic sequence-specific cleavage of target messenger RNA (mRNA) molecules, resulting in the silencing of gene products in an efficient and precise manner. One apparent application of this technology is the knockdown of genes responsible for cancer progression, including pro-proliferative oncogenes, inhibitors of apoptosis, and mediators of angiogenesis. Delivery of siRNAs into particular cells has remained the principal obstacle to the realization of the potential of RNA interference (RNAi) in the clinic. Several groups have worked to develop carriers that facilitate siRNA delivery into ovarian cancer cells in mouse models of ovarian cancer. The results have been promising, often leading to significant survival extension. Such benefit is critical for a disease that is characterized by very poor outcomes and demands novel treatment options. This review describes advancements in siRNA delivery for the treatment of ovarian cancer.
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Role of parental atopy in cows milk allergy: a population-based study.
Ann. Allergy Asthma Immunol.
PUBLISHED: 01-21-2013
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A family history of atopy has been considered an independent risk factor for atopic diseases in children.
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Suppression of inflammatory responses during myelin oligodendrocyte glycoprotein-induced experimental autoimmune encephalomyelitis is regulated by AKT3 signaling.
J. Immunol.
PUBLISHED: 01-18-2013
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AKT3, a member of the serine/threonine kinase AKT family, is involved in a variety of biologic processes. AKT3 is expressed in immune cells and is the major AKT isoform in the CNS representing 30% of the total AKT expressed in spinal cord, and 50% in the brain. Myelin-oligodendrocyte glycoprotein-induced experimental autoimmune encephalomyelitis (EAE) is a mouse model in which lymphocytes and monocytes enter the CNS, resulting in inflammation, demyelination, and axonal injury. We hypothesized that during EAE, deletion of AKT3 would negatively affect the CNS of AKT3(-/-) mice, making them more susceptible to CNS damage. During acute EAE, AKT3(-/-)mice were more severely affected than wild type (WT) mice. Evaluation of spinal cords showed that during acute and chronic disease, AKT3(-/-) spinal cords had more demyelination compared with WT spinal cords. Quantitative RT-PCR determined higher levels of IL-2, IL-17, and IFN-? mRNA in spinal cords from AKT3(-/-) mice than WT. Experiments using bone marrow chimeras demonstrated that AKT3(-/-) mice receiving AKT3-deficient bone marrow cells had elevated clinical scores relative to control WT mice reconstituted with WT cells, indicating that altered function of both CNS cells and bone marrow-derived immune cells contributed to the phenotype. Immunohistochemical analysis revealed decreased numbers of Foxp3(+) regulatory T cells in the spinal cord of AKT3(-/-) mice compared with WT mice, whereas in vitro suppression assays showed that AKT3-deficient Th cells were less susceptible to regulatory T cell-mediated suppression than their WT counterparts. These results indicate that AKT3 signaling contributes to the protection of mice against EAE.
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Cathepsin-mediated necrosis controls the adaptive immune response by Th2 (T helper type 2)-associated adjuvants.
J. Biol. Chem.
PUBLISHED: 01-07-2013
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Immunologic adjuvants are critical components of vaccines, but it remains unclear how prototypical adjuvants enhance the adaptive immune response. Recent studies have shown that necrotic cells could trigger an immune response. Although most adjuvants have been shown to be cytotoxic, this activity has traditionally been considered a side effect. We set out to test the role of adjuvant-mediated cell death in immunity and found that alum, the most commonly used adjuvant worldwide, triggers a novel form of cell death in myeloid leukocytes characterized by cathepsin-dependent lysosome-disruption. We demonstrated that direct lysosome-permeabilization with a soluble peptide, Leu-Leu-OMe, mimics the alum-like form of necrotic cell death in terms of cathepsin dependence and cell-type specificity. Using a combination of a haploid genetic screen and cathepsin-deficient cells, we identified specific cathepsins that control lysosome-mediated necrosis. We identified cathepsin C as critical for Leu-Leu-OMe-induced cell death, whereas cathepsins B and S were required for alum-mediated necrosis. Consistent with a role of necrotic cell death in adjuvant effects, Leu-Leu-OMe replicated an alum-like immune response in vivo, characterized by dendritic cell activation, granulocyte recruitment, and production of Th2-associated antibodies. Strikingly, cathepsin C deficiency not only blocked Leu-Leu-OMe-mediated necrosis but also impaired Leu-Leu-OMe-enhanced immunity. Together our findings suggest that necrotic cell death is a powerful mediator of a Th2-associated immune response.
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Impaired lipopolysaccharide responsiveness of cord blood mononuclear cells and the risk of asthma: a longitudinal study.
Pediatr. Res.
PUBLISHED: 01-01-2013
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We previously demonstrated that the proliferative response to lipopolysaccharide (LPS) in cord blood mononuclear cells (CBMCs) is negatively correlated with the induced expression of interleukin (IL)-4. Our aim, therefore, was to examine whether an impaired cellular response to LPS in infancy is associated with the risk for asthma.
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Bacterial biogeography of the human digestive tract.
Sci Rep
PUBLISHED: 06-14-2011
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We present bacterial biogeography as sampled from the human gastrointestinal tract of four healthy subjects. This study generated >32 million paired-end sequences of bacterial 16S rRNA genes (V3 region) representing >95,000 unique operational taxonomic units (OTUs; 97% similarity clusters), with >99% Goods coverage for all samples. The highest OTU richness and phylogenetic diversity was found in the mouth samples. The microbial communities of multiple biopsy sites within the colon were highly similar within individuals and largely distinct from those in stool. Within an individual, OTU overlap among broad site definitions (mouth, stomach/duodenum, colon and stool) ranged from 32-110 OTUs, 25 of which were common to all individuals and included OTUs affiliated with Faecalibacterium prasnitzii and the TM7 phylum. This first comprehensive characterization of the abundant and rare microflora found along the healthy human digestive tract represents essential groundwork to investigate further how the human microbiome relates to health and disease.
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In vitro culture medium influences the vaccine efficacy of Mycobacterium bovis BCG.
Vaccine
PUBLISHED: 05-25-2011
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The varied rates of protection induced by Mycobacterium bovis BCG vaccine against tuberculosis has been attributed to many factors such as genetic variability among BCG strains, rapid clearance of BCG in some populations, and different levels of previous exposure of vaccinated populations to environmental mycobacteria. However, the methods and conditions employed to prepare this vaccine for human usage by various manufacturers have not been investigated as potential factors contributing to the variation in vaccine efficacy. A review of the literature indicates discrepancies between the approach for growing BCG vaccine in the laboratory to assess immune responses and protective ability in animal models, and that employed for production of the vaccine for administration to humans. One of the major differences is in the growth medium used for routine propagation in the laboratory and the one used for bulk vaccine production by manufacturers. Here we compared the immunogenicity of the BCG vaccine grown in Middlebrook 7H9 medium, the most commonly used medium in laboratory studies, against that grown in Sauton medium, which is used for growing BCG by most manufacturers. Our results showed clear differences in the behavior of BCG grown in these different culture media. Compared to BCG grown in Middlebrook 7H9 medium, BCG grown in Sauton media was more persistent inside macrophages, more effective at inhibiting apoptosis of infected cells, induced stronger inflammatory responses and stimulated less effective immunity against aerosol challenge with a virulent Mtb strain. These findings suggested that the growth medium used for producing BCG vaccine is an important factor that deserves increased scrutiny in ongoing efforts to produce more consistently effective vaccines against Mtb.
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Loss of the receptor tyrosine kinase Axl leads to enhanced inflammation in the CNS and delayed removal of myelin debris during experimental autoimmune encephalomyelitis.
J Neuroinflammation
PUBLISHED: 05-15-2011
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Axl, together with Tyro3 and Mer, constitute the TAM family of receptor tyrosine kinases. In the nervous system, Axl and its ligand Growth-arrest-specific protein 6 (Gas6) are expressed on multiple cell types. Axl functions in dampening the immune response, regulating cytokine secretion, clearing apoptotic cells and debris, and maintaining cell survival. Axl is upregulated in various disease states, such as in the cuprizone toxicity-induced model of demyelination and in multiple sclerosis (MS) lesions, suggesting that it plays a role in disease pathogenesis. To test for this, we studied the susceptibility of Axl-/- mice to experimental autoimmune encephalomyelitis (EAE), an animal model for multiple sclerosis.
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Regulation of Greatwall kinase during Xenopus oocyte maturation.
Mol. Biol. Cell
PUBLISHED: 05-05-2011
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Greatwall kinase has been identified as a key element in M phase initiation and maintenance in Drosophila, Xenopus oocytes/eggs, and mammalian cells. In M phase, Greatwall phosphorylates endosulfine and related proteins that bind to and inhibit protein phosphatase 2A/B55, the principal phosphatase for Cdk-phosphorylated substrates. We show that Greatwall binds active PP2A/B55 in G2 phase oocytes but dissociates from it when progesterone-treated oocytes reach M phase. This dissociation does not require Greatwall kinase activity or phosphorylation at T748 in the presumptive T loop of the kinase. A mutant K71M Greatwall, also known as Scant in Drosophila, induces M phase in the absence of progesterone when expressed in oocytes, despite its reduced stability and elevated degradation by the proteasome. M phase induction by Scant Greatwall requires protein synthesis but is not associated with altered binding or release of PP2A/B55 as compared to wild-type Greatwall. However, in vitro studies with Greatwall proteins purified from interphase cells indicate that Scant, but not wild-type Greatwall, has low but detectable activity against endosulfine. These results demonstrate progesterone-dependent regulation of the PP2A/B55-Greatwall interaction during oocyte maturation and suggest that the cognate Scant Greatwall mutation has sufficient constitutive kinase activity to promote M phase in Xenopus oocytes.
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EXT2-positive multiple hereditary osteochondromas with some features suggestive of metachondromatosis.
Skeletal Radiol.
PUBLISHED: 05-04-2011
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Metachondromatosis (MC) and hereditary multiple osteochondromas (HMO) are thought to be distinct disorders, each with characteristic x-ray and clinical features. Radiographic differences are the current mainstay of differential diagnosis. Both disorders are autosomal dominant, but the majority of patients with HMO have mutations in EXT-1 or EXT 2 genes. The genetic defect in MC is unknown, although recent studies indicate a possible identifiable mutation. The cancer risk in HMO is thought to be greater than in MC, although the small number of cases make such conjecture imprecise. The purpose of this report is to review existing literature and examine whether radiographic findings in HMO and MC can be reliable as a stand-alone means of differential diagnosis. Three members of a multi-generational family with an autosomal dominant exostosis syndrome were studied by clinical examination and complete skeletal survey. The roentgenographic characteristics of all osteochondromas were analyzed. The father underwent gene sequencing for EXT-1 and EXT-2, which revealed a novel EXT-2 mutation. Typical radiographic and clinical findings of both HMO and MC were seen throughout the family as well as in individuals. These family study findings contradict many of the long-standing clinical and x-ray diagnostic criteria for differentiating MC from HMO. The phenotypic crossover between the two conditions in this family, and results of genetic analysis, suggest that in the absence of a definitive genetic diagnosis, radiographic and clinical diagnosis of past and future cases HMO and MC may not be as reliable as previously assumed.
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Diagnosis and treatment of osteochondritis dissecans.
J Am Acad Orthop Surg
PUBLISHED: 05-04-2011
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This clinical practice guideline is based on a series of systematic reviews of published studies in the available literature on the diagnosis and treatment of osteochondritis dissecans of the knee. None of the 16 recommendations made by the work group is graded as strong; most are graded inconclusive; two are graded weak; and four are consensus statements. Both of the weak recommendations are related to imaging evaluation. For patients with knee symptoms, radiographs of the joint may be obtained to identify the lesion. For patients with radiographically apparent lesions, MRI may be used to further characterize the osteochondritis dissecans lesion or identify other knee pathology.
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A recombinant Mycobacterium smegmatis induces potent bactericidal immunity against Mycobacterium tuberculosis.
Nat. Med.
PUBLISHED: 04-18-2011
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We report the involvement of an evolutionarily conserved set of mycobacterial genes, the esx-3 region, in evasion of bacterial killing by innate immunity. Whereas high-dose intravenous infections of mice with the rapidly growing mycobacterial species Mycobacterium smegmatis bearing an intact esx-3 locus were rapidly lethal, infection with an M. smegmatis ?esx-3 mutant (here designated as the IKE strain) was controlled and cleared by a MyD88-dependent bactericidal immune response. Introduction of the orthologous Mycobacterium tuberculosis esx-3 genes into the IKE strain resulted in a strain, designated IKEPLUS, that remained susceptible to innate immune killing and was highly attenuated in mice but had a marked ability to stimulate bactericidal immunity against challenge with virulent M. tuberculosis. Analysis of these adaptive immune responses indicated that the highly protective bactericidal immunity elicited by IKEPLUS was dependent on CD4(+) memory T cells and involved a distinct shift in the pattern of cytokine responses by CD4(+) cells. Our results establish a role for the esx-3 locus in promoting mycobacterial virulence and also identify the IKE strain as a potentially powerful candidate vaccine vector for eliciting protective immunity to M. tuberculosis.
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A novel mutation in the C3 gene and recurrent invasive pneumococcal infection: a clue for vaccine development.
Mol. Immunol.
PUBLISHED: 04-07-2011
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We identified a 4 year-old boy born to a consanguineous marriage with C3 deficiency after three episodes of invasive pneumococcal disease. The efficacy of anti-pneumococcal vaccination in C3 deficient patients is not clear.
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The prevalence and natural course of food protein-induced enterocolitis syndrome to cows milk: a large-scale, prospective population-based study.
J. Allergy Clin. Immunol.
PUBLISHED: 03-08-2011
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The prevalence and natural history for food protein-induced enterocolitis syndrome (FPIES) have not been determined.
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The treatment of symptomatic osteoporotic spinal compression fractures.
J Am Acad Orthop Surg
PUBLISHED: 03-04-2011
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This clinical practice guideline is based on a series of systematic reviews of published studies on the treatment of symptomatic osteoporotic spinal compression fractures. Of 11 recommendations, one is strong; one, moderate; three, weak; and six, inconclusive. The strong recommendation is against the use of vertebroplasty to treat the fractures; the moderate recommendation is for the use of calcitonin for 4 weeks following the onset of fracture. The weak recommendations address the use of ibandronate and strontium ranelate to prevent additional symptomatic fractures, the use of L2 nerve root blocks to treat the pain associated with L3 or L4 fractures, and the use of kyphoplasty to treat symptomatic fractures in patients who are neurologically intact.
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Advances in translational neuropathic research: example of enantioselective pharmacokinetic-pharmacodynamic modeling of ketamine-induced pain relief in complex regional pain syndrome.
Curr Pain Headache Rep
PUBLISHED: 03-02-2011
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Historically, complex regional pain syndrome (CRPS) was poorly defined, which meant that scientists and clinicians faced much uncertainty in the study, diagnosis, and treatment of the syndrome. The problem could be attributed to a nonspecific diagnostic criteria, unknown pathophysiologic causes, and limited treatment options. The two forms of CRPS still are painful, debilitating disorders whose sufferers carry heavy emotional burdens. Current research has shown that CRPS I and CRPS II are distinctive processes, and the presence or absence of a partial nerve lesion distinguishes them apart. Ketamine has been the focus of various studies involving the treatment of CRPS; however, currently, there is incomplete data from evidence-based studies. The question as to why ketamine is effective in controlling the symptoms of a subset of patients with CRPS and not others remains to be answered. A possible explanation to this phenomenon is pharmacogenetic differences that may exist in different patient populations. This review summarizes important translational work recently published on the treatment of CRPS using ketamine.
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The time course of the tonic oculomotor proprioceptive signal in area 3a of somatosensory cortex.
J. Neurophysiol.
PUBLISHED: 02-23-2011
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A proprioceptive representation of eye position exists in area 3a of primate somatosensory cortex (Wang X, Zhang M, Cohen IS, Goldberg ME. Nat Neurosci 10: 640-646, 2007). This eye position signal is consistent with a fusimotor response (Taylor A, Durbaba R, Ellaway PH, Rawlinson S. J Physiol 571: 711-723, 2006) and has two components during a visually guided saccade task: a short-latency phasic response followed by a tonic response. While the early phasic response can be excitatory or inhibitory, it does not accurately reflect the eyes orbital position. The late tonic response appears to carry the proprioceptive eye position signal, but it is not clear when this component emerges and whether the onset of this signal is reliable. To test the temporal dynamics of the tonic proprioceptive signal, we used an oculomotor smooth pursuit task in which saccadic eye movements and phasic proprioceptive responses are suppressed. Our results show that the tonic proprioceptive eye position signal consistently lags the actual eye position in the orbit by ~60 ms under a variety of eye movement conditions. To confirm the proprioceptive nature of this signal, we also studied the responses of neurons in a vestibuloocular reflex (VOR) task in which the direction of gaze was held constant; response profiles and delay times were similar in this task, suggesting that this signal does not represent angle of gaze and does not receive visual or vestibular inputs. The length of the delay suggests that the proprioceptive eye position signal is unlikely to be used for online visual processing for action, although it could be used to calibrate an efference copy signal.
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Serum biomarker panels for the detection of pancreatic cancer.
Clin. Cancer Res.
PUBLISHED: 02-18-2011
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Serum-biomarker based screening for pancreatic cancer could greatly improve survival in appropriately targeted high-risk populations.
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Spatial memory using active allothetic place avoidance in adult rats after isoflurane anesthesia: a potential model for postoperative cognitive dysfunction.
J Neurosurg Anesthesiol
PUBLISHED: 01-29-2011
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We described a paradigm of active allothetic place avoidance (AAPA) as a measure of spatial memory in adult rats. We hypothesized that, pending successful AAPA training, treatment with isoflurane would trigger spatial memory deficits.
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Lysine auxotrophy combined with deletion of the SecA2 gene results in a safe and highly immunogenic candidate live attenuated vaccine for tuberculosis.
PLoS ONE
PUBLISHED: 01-10-2011
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Tuberculosis (TB) caused by Mycobacterium tuberculosis remains a major global health problem, despite the widespread use of the M. bovis Bacille Calmette-Guerin (BCG) vaccine and the availability of drug therapies. In recent years, the high incidence of coinfection of M. tuberculosis and HIV, as well as escalating problems associated with drug resistance, has raised ominous concerns with regard to TB control. Vaccination with BCG has not proven highly effective in controlling TB, and also has been associated with increasing concerns about the potential for the vaccine to cause disseminated mycobacterial infection in HIV infected hosts. Thus, the development of an efficacious and safe TB vaccine is generally viewed as a critical to achieving control of the ongoing global TB pandemic. In the current study, we have analyzed the vaccine efficacy of an attenuated M. tuberculosis strain that combines a mutation that enhances T cell priming (?secA2) with a strongly attenuating lysine auxotrophy mutation (?lysA). The ?secA2 mutant was previously shown to be defective in the inhibition of apoptosis and markedly increased priming of antigen-specific CD8(+) T cells in vivo. Similarly, the ?secA2?lysA strain retained enhanced apoptosis and augmented CD8(+) T cell stimulatory effects, but with a noticeably improved safety profile in immunosuppressed mice. Thus, the M. tuberculosis ?secA2?lysA mutant represents a live attenuated TB vaccine strain with the potential to deliver increased protection and safety compared to standard BCG vaccination.
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Nanoparticle-mediated delivery of siRNA targeting Parp1 extends survival of mice bearing tumors derived from Brca1-deficient ovarian cancer cells.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 12-27-2010
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Inhibition of the DNA repair enzyme poly(ADP-ribose) polymerase 1 (PARP1) with small molecules has been shown to be an effective treatment for ovarian cancer with BRCA mutations. Here, we report the in vivo administration of siRNA to Parp1 in mouse models of ovarian cancer. A unique member of the lipid-like materials known as lipidoids is shown to deliver siRNA to disseminated murine ovarian carcinoma allograft tumors following intraperitoneal (i.p.) injection. siParp1 inhibits cell growth, primarily by induction of apoptosis, in Brca1-deficient cells both in vitro and in vivo. Additionally, the treatment extends the survival of mice bearing tumors derived from Brca1-deficient ovarian cancer cells but not from Brca1 wild-type cells, confirming the proposed mechanism of synthetic lethality. Because there are 17 members of the Parp family, the inherent complementarity of RNA affords a high level of specificity for therapeutically addressing Parp1 in the context of impaired homologous recombination.
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Refractory periodontitis population characterized by a hyperactive oral neutrophil phenotype.
J. Periodontol.
PUBLISHED: 11-16-2010
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Neutrophils, in addition to being the primary protective component of the innate immune system, also contribute to periodontal destruction through production of reactive oxygen species (ROS), which cause damage to connective tissues and extracellular matrix after neutrophil activation. We have previously shown that hyperactive neutrophils are present in peripheral blood samples of patients diagnosed with refractory periodontitis. To test the hypothesis that oral neutrophil hyperactivity is related to periodontal disease severity, we used a flow cytometric approach to isolate and analyze oral neutrophil ROS (oROS) production in a refractory periodontal disease patient population.
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A novel role for greatwall kinase in recovery from DNA damage.
Cell Cycle
PUBLISHED: 11-14-2010
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Activation of the DNA damage response (DDR) is critical for genomic integrity and tumor suppression. The occurrence of DNA damage quickly evokes the DDR through ATM/ATR-dependent signal transduction, which promotes DNA repair and activates the checkpoint to halt cell cycle progression. The "turn off" process of the DDR upon satisfaction of DNA repair, also known as "checkpoint recovery", involves deactivation of DDR elements, but the mechanism is poorly understood. Greatwall kinase (Gwl) has been identified as a key element in the G(2)/M transition and helps maintain M phase through inhibition of PP 2A/B55?, the principal phosphatase for Cdk-phosphorylated substrates. Here we show that Gwl also promotes recovery from DNA damage and is itself directly inhibited by the DNA damage response (DDR). In Xenopus egg extracts, immunodepletion of Gwl increased the DDR to damaged DNA, whereas addition of wild type, but not kinase dead Gwl, inhibited the DDR. The removal of damaged DNA from egg extracts leads to recovery from checkpoint arrest and entry into mitosis, a process impaired by Gwl depletion and enhanced by Gwl overexpression. Moreover, activation of Cdk1 after the removal of damaged DNA is regulated by Gwl. Collectively, these results defines Gwl as a new regulator of the DDR, which plays an important role in recovery from DNA damage.
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Surround suppression sharpens the priority map in the lateral intraparietal area.
J. Neurosci.
PUBLISHED: 09-24-2010
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In the visual world, stimuli compete with each other for allocation of the brains limited processing resources. Computational models routinely invoke wide-ranging mutually suppressive interactions in spatial priority maps to implement active competition for attentional and saccadic allocation, but such suppressive interactions have not been physiologically described, and their existence is controversial. Much evidence implicates the lateral intraparietal area as a candidate priority map in the macaque (Macaca mulatta). Here, we demonstrate that the responses of neurons in the lateral intraparietal area (LIP) to a task-irrelevant distractor are strongly suppressed when the monkey plans saccades to locations outside their receptive fields. Suppression can be evoked both by flashed visual stimuli and by a memorized saccade plan. The suppressive surrounds of LIP neurons are spatially tuned and wide ranging. Increasing the monkeys motivation enhances target-distractor discriminability by enhancing both distractor suppression and the saccade goal representation; these changes are accompanied by correlated improvements in behavioral performance.
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Contribution of chronic pain and neuroticism to abnormal forebrain gray matter in patients with temporomandibular disorder.
Neuroimage
PUBLISHED: 09-22-2010
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Cortical plasticity is thought to occur following continuous barrage of nociceptive afferent signals to the brain. Hence, chronic pain is presumed to induce anatomical and physiological changes in the brain over time. Inherent factors, some pre-dating the onset of chronic pain, may also contribute to brain abnormalities present in patients. In this study we used structural MRI to examine whether patients with chronic temporomandibular (TMD) pain have abnormalities in gray matter (GM) within brain areas implicated in pain, modulation and sensorimotor function. We found that patients with TMD have cortical thickening in the primary somatosensory cortex (S1), frontal polar and the ventrolateral prefrontal cortex (PFC). These findings provide a structural basis for previous findings of TMD pain and cognitive sluggishness in TMD. We then examined the contribution of TMD characteristics to GM abnormalities. We found that 1) GM in the sensory thalamus positively correlated to TMD duration, 2) cortical thickness in the primary motor (M1) and the anterior mid-cingulate cortices (aMCC) were negatively correlated to pain intensity, and 3) pain unpleasantness was negatively correlated to cortical thickness in the orbitofrontal cortex (OFC). These findings suggest that an individuals TMD pain history contributes to GM in the brain. Lastly, we examined the contribution of a potential pre-existing vulnerability due to neuroticism. In the TMD patients, we found that there was an abnormal positive correlation between neuroticism and OFC thickness, in contrast to the negative correlation found in the healthy controls. Therefore, neuroticism may contribute to TMD pathophysiology. In sum, our data suggest that GM in the brain of patients with chronic TMD pain can be shaped by both personality and pain characteristics.
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Diagnosis and treatment of acute Achilles tendon rupture.
J Am Acad Orthop Surg
PUBLISHED: 08-03-2010
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This clinical practice guideline is based on a series of systematic reviews of published studies in the available literature on the diagnosis and treatment of acute Achilles tendon rupture. None of the 16 recommendations made by the work group was graded as strong; most are graded inconclusive; four are graded weak; two are graded as moderate strength; and two are consensus statements. The two moderate-strength recommendations include the suggestions for early postoperative protective weight bearing and for the use of protective devices that allow for postoperative mobilization.
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Single-dose pharmacokinetics and tolerability of telavancin in elderly men and women.
Pharmacotherapy
PUBLISHED: 07-27-2010
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To assess the safety and tolerability, and the effect of sex on the pharmacokinetic disposition, of a single intravenous dose of telavancin 10 mg/kg in elderly (> or = 65 yrs) subjects.
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Pharmacodynamic profiles of ketamine (R)- and (S)- with 5-day inpatient infusion for the treatment of complex regional pain syndrome.
Pain Physician
PUBLISHED: 07-22-2010
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Ketamine might be effective in blocking central sensitization of pain transmission neurons through its effect on NMDA receptors in refractory Complex Regional Pain Syndrome (CRPS) patients. At higher doses, ketamine infusions can be associated with significant risks; outpatient therapy requires return visits for a 10-day period with variable efficacy and duration.
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Activity in V4 reflects the direction, but not the latency, of saccades during visual search.
J. Neurophysiol.
PUBLISHED: 07-07-2010
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We constantly make eye movements to bring objects of interest onto the fovea for more detailed processing. Activity in area V4, a prestriate visual area, is enhanced at the location corresponding to the target of an eye movement. However, the precise role of activity in V4 in relation to these saccades and the modulation of other cortical areas in the oculomotor system remains unknown. V4 could be a source of visual feature information used to select the eye movement, or alternatively, it could reflect the locus of spatial attention. To test these hypotheses, we trained monkeys on a visual search task in which they were free to move their eyes. We found that activity in area V4 reflected the direction of the upcoming saccade but did not predict the latency of the saccade in contrast to activity in the lateral intraparietal area (LIP). We suggest that the signals in V4, unlike those in LIP, are not directly involved in the generation of the saccade itself but rather are more closely linked to visual perception and attention. Although V4 and LIP have different roles in spatial attention and preparing eye movements, they likely perform complimentary processes during visual search.
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Proteasome inhibitors prevent caspase-1-mediated disease in rodents challenged with anthrax lethal toxin.
Am. J. Pathol.
PUBLISHED: 07-01-2010
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NOD-like receptors (NLRs) and caspase-1 are critical components of innate immunity, yet their over-activation has been linked to a long list of microbial and inflammatory diseases, including anthrax. The Bacillus anthracis lethal toxin (LT) has been shown to activate the NLR Nalp1b and caspase-1 and to induce many symptoms of the anthrax disease in susceptible murine strains. In this study we tested whether it is possible to prevent LT-mediated disease by pharmacological inhibition of caspase-1. We found that caspase-1 and proteasome inhibitors blocked LT-mediated caspase-1 activation and cytolysis of LT-sensitive (Fischer and Brown-Norway) rat macrophages. The proteasome inhibitor NPI-0052 also prevented disease progression and death in susceptible Fischer rats and increased survival in BALB/c mice after LT challenge. In addition, NPI-0052 blocked rapid disease progression and death in susceptible Fischer rats and BALB/c mice challenged with LT. In contrast, Lewis rats, which harbor LT-resistant macrophages, showed no signs of caspase-1 activation after LT injection and did not exhibit rapid disease progression. Taken together, our findings indicate that caspase-1 activation is critical for rapid disease progression in rodents challenged with LT. Our studies indicate that pharmacological inhibition of NLR signaling and caspase-1 can be used to treat inflammatory diseases.
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Optical measurement of rectal microvasculature as an adjunct to flexible sigmoidosocopy: gender-specific implications.
Cancer Prev Res (Phila)
PUBLISHED: 06-22-2010
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Flexible sigmoidoscopy is a robust, clinically validated, and widely available colorectal cancer screening technique that is currently sanctioned by major guideline organizations. Given that endoscopic visualization is generally limited to the distal third of the colon and women tend to have a proclivity for proximal lesions, the flexible sigmoidoscopy performance is markedly inferior in women than in men. Our group has shown that by using a novel light-scattering approach, we were able to detect an early increase in blood supply (EIBS) in the distal colonic mucosa, which served as a marker of field carcinogenesis and, hence, proximal neoplasia. Therefore, we sought to ascertain whether rectal EIBS would improve flexible sigmoidoscopy, especially in women. A polarization-gated spectroscopy fiber-optic probe was used to assess EIBS in the endoscopically normal rectum (n = 366). When compared with gender-matched neoplasia-free controls, females with advanced proximal neoplasia (n = 10) had a robust (60%; P = 0.002) increase in rectal mucosal oxyhemoglobin content whereas the effect size in males was less marked (33%; P = 0.052). In women, addition of rectal oxyhemoglobin tripled the sensitivity for advanced neoplasia over flexible sigmoidoscopy alone. Indeed, the performance characteristics seemed to be excellent (sensitivity, 100%; specificity, 76.8%; positive predictive value, 32.6%; and negative predictive value, 100%). A variety of nonneoplastic factors were assessed and did not confound the relationship between rectal EIBS and advanced neoplasia. Therefore, using rectal EIBS in combination with flexible sigmoidoscopy mitigated the gender gap and may allow flexible sigmoidoscopy to be considered as a viable colorectal cancer screening test in women.
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A parallel chiral-achiral liquid chromatographic method for the determination of the stereoisomers of ketamine and ketamine metabolites in the plasma and urine of patients with complex regional pain syndrome.
Talanta
PUBLISHED: 06-10-2010
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A parallel chiral/achiral LC-MS/MS assay has been developed and validated to measure the plasma and urine concentrations of the enantiomers of ketamine, (R)- and (S)-Ket, in complex regional pain syndrome (CRPS) patients receiving a 5-day continuous infusion of a sub-anesthetic dose of (R,S)-Ket. The method was also validated for the determination of the enantiomers of the Ket metabolites norketamine, (R)- and (S)-norKet and dehydronorketamine, (R)- and (S)-DHNK, as well as the diastereomeric metabolites hydroxynorketamine, (2S,6S)-/(2R,6R)-HNK and two hydroxyketamines, (2S,6S)-HKet and (2S,6R)-Hket. In this method, (R,S)-Ket, (R,S)-norKet and (R,S)-DHNK and the diastereomeric hydroxyl-metabolites were separated and quantified using a C(18) stationary phase and the relative enantiomeric concentrations of (R,S)-Ket, (R,S)-norKet and (R,S)-DHNK were determined using an AGP-CSP. The analysis of the results of microsomal incubations of (R)- and (S)-Ket and a plasma and urine sample from a CRPS patient indicated the presence of 10 additional compounds and glucuronides. The data from the analysis of the patient sample also demonstrated that a series of HNK metabolites were the primary metabolites in plasma and (R)- and (S)-DHNK were the major metabolites found in urine. The results suggest that norKet is the initial, but not the primary metabolite and that downstream norKet metabolites play a role in (R,S)-Ket-related pain relief in CRPS patients.
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Role of clevidipine butyrate in the treatment of acute hypertension in the critical care setting: a review.
Vasc Health Risk Manag
PUBLISHED: 06-05-2010
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Acutely elevated blood pressure in the critical care setting is associated with a higher risk of acute end-organ damage (eg, myocardial ischemia, stroke, and renal failure) and perioperative bleeding. Urgent treatment and careful blood pressure control are crucial to prevent significant morbidity. Clevidipine butyrate (Cleviprex) is an ultrashort-acting, third-generation intravenous calcium channel blocker. It is an arterial-selective vasodilator with no venodilatory or myocardial depressive effects. Clevidipine has an extremely short half-life of approximately 1 minute as it is rapidly metabolized by blood and tissue esterases. These metabolites are then primarily eliminated through urine and fecal pathways. The rapid onset and the short duration of action permit tighter and closer adjustment of the blood pressure than is possible with other intravenous agents.
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Mass balance and pharmacokinetics of [14C]telavancin following intravenous administration to healthy male volunteers.
Antimicrob. Agents Chemother.
PUBLISHED: 06-01-2010
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The mass balance and pharmacokinetics of telavancin, a semisynthetic lipoglycopeptide antimicrobial agent, were characterized in an open-label, phase 1 study of six healthy male subjects. After a single 1-h intravenous infusion of 10 mg/kg [14C]telavancin (0.68 microCi/kg), blood, urine, and feces were collected at regular intervals up to 216 h postdose. Whole blood, plasma, urine, and fecal samples were assayed for total radioactivity using scintillation counting; plasma and urine were also assayed for parent drug and metabolites using liquid chromatography with tandem mass spectrometry. The concentration-time profiles for telavancin and total radioactivity in plasma were comparable from 0 to 24 h after the study drug administration. Telavancin accounted for >95% and 83% of total radioactivity in plasma at 12 h and 24 h, respectively. By 216 h, approximately 76% of the total administered dose was recovered in urine while only 1% was collected in feces. Unchanged telavancin accounted for most (83%) of the eliminated dose. Telavancin metabolite THRX-651540 along with two other hydroxylated metabolites (designated M1 and M2) accounted for the remaining radioactivity recovered from urine. The mean concentrations of total radioactivity in whole blood were lower than the concentration observed in plasma, and mean concentrations of THRX-651540 in plasma were minimal relative to mean plasma telavancin concentrations. These observations demonstrate that most of an administered telavancin dose is eliminated unchanged via the kidneys. Intravenous telavancin at 10 mg/kg was well tolerated by all subjects.
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Treatment of glenohumeral osteoarthritis.
J Am Acad Orthop Surg
PUBLISHED: 06-01-2010
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This clinical practice guideline is based on a systematic review of published studies on the treatment of glenohumeral osteoarthritis in the adult patient population. Of the 16 recommendations addressed, nine are inconclusive. Two were reached by consensus-that physicians use perioperative mechanical and/or chemical venous thromboembolism prophylaxis for shoulder arthroplasty patients and that total shoulder arthroplasty not be performed in patients with glenohumeral osteoarthritis who have an irreparable rotator cuff tear. Four options were graded as weak: the use of injectable viscosupplementation; total shoulder arthroplasty and hemiarthroplasty as treatment; avoiding shoulder arthroplasty by surgeons who perform fewer than two shoulder arthroplasties per year (to reduce the risk of immediate postoperative complications); and the use of keeled or pegged all-polyethylene cemented glenoid components. The single moderate-rated recommendation was for the use of total shoulder arthroplasty rather than hemiarthroplasty. Management of glenohumeral osteoarthritis remains controversial; the scientific evidence on this topic can be significantly improved.
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Attention, intention, and priority in the parietal lobe.
Annu. Rev. Neurosci.
PUBLISHED: 03-03-2010
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For many years there has been a debate about the role of the parietal lobe in the generation of behavior. Does it generate movement plans (intention) or choose objects in the environment for further processing? To answer this, we focus on the lateral intraparietal area (LIP), an area that has been shown to play independent roles in target selection for saccades and the generation of visual attention. Based on results from a variety of tasks, we propose that LIP acts as a priority map in which objects are represented by activity proportional to their behavioral priority. We present evidence to show that the priority map combines bottom-up inputs like a rapid visual response with an array of top-down signals like a saccade plan. The spatial location representing the peak of the map is used by the oculomotor system to target saccades and by the visual system to guide visual attention.
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Treatment of distal radius fractures.
J Am Acad Orthop Surg
PUBLISHED: 03-02-2010
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The clinical practice guideline is based on a systematic review of published studies on the treatment of distal radius fractures in adults. None of the 29 recommendations made by the work group was graded as strong; most are graded as inconclusive or consensus; seven are graded as weak. The remaining five moderate-strength recommendations include surgical fixation, rather than cast fixation, for fractures with postreduction radial shortening >3 mm, dorsal tilt >10 degrees , or intra-articular displacement or step-off >2 mm; use of rigid immobilization rather than removable splints for nonsurgical treatment; making a postreduction true lateral radiograph of the carpus to assess dorsal radial ulnar joint alignment; beginning early wrist motion following stable fixation; and recommending adjuvant treatment with vitamin C to prevent disproportionate pain.
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Effect of Telavancin on the pharmacokinetics of the cytochrome P450 3A probe substrate midazolam: a randomized, double-blind, crossover study in healthy subjects.
Pharmacotherapy
PUBLISHED: 01-27-2010
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To examine the effect of telavancin, a lipoglycopeptide antibiotic with potent gram-positive activity, on the pharmacokinetics of midazolam, a cytochrome P450 (CYP) 3A probe substrate. Design. Phase I, randomized, double-blind, placebo-controlled, crossover study. Setting. Clinical research center.
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Enantioselective pharmacokinetics of (R)- and (S)-ketamine after a 5-day infusion in patients with complex regional pain syndrome.
Chirality
PUBLISHED: 01-26-2010
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This study determined the pharmacokinetics and pharmacodynamics of (R)- and (S)-ketamine and (R)- and (S)-norketamine following a 5-day moderate dose, as a continuous (R,S)-ketamine infusion in complex regional pain syndrome (CRPS) patients.
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Early exposure to cows milk protein is protective against IgE-mediated cows milk protein allergy.
J. Allergy Clin. Immunol.
PUBLISHED: 01-25-2010
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The diversity in the perceived prevalence, recovery, and risk factors for cows milk allergy (CMA) necessitated a large-scale, population-based prospective study.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.