bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chiral N,N′‐Dioxide–Yttrium Triflate Complexes‐Catalyzed Asymmetric Aldol Cyclization of α‐Keto Esters with α‐Isothiocyanato Imide
Authors: Zhao Xiaohu , Xie Mingsheng , Liu Xiaohua , Zhang Yulong , Xiao Xiao , Lin Lili , Feng Xiaoming 
Published: November 2013

AbstractA highly effective aldol cyclization of α‐isothiocyanato imide to both β,γ‐unsaturated α‐keto esters and aryl‐substituted α‐keto esters has been developed. A chiral N,N′‐dioxide–yttrium triflate complex was used as the catalyst. A series of cyclic thiocarbamates bearing chiral quaternary stereocenters was synthesized in good to high yields, excellent diastereo‐ (up to 25:1 dr) and enantioselectivities (up to 99 % ee). In addition, the reaction could be carried out on a gram‐scale, and other functionalized derivatives are also conveniently transformed. Interestingly, a discrepancy of diastereoselection was observed between the reactions of β,γ‐unsaturated α‐keto esters and aryl‐substituted α‐keto esters. Moreover, a substrate dependency of non‐linear effects was observed in this reaction. On the basis of the experimental results and the absolute configuration of the products, possible catalytic models have been proposed to explain the origin of the asymmetric process.magnified image
Detection of an ABCA1 variant associated with type 2 diabetes mellitus susceptibility for biochemistry and genetic laboratory courses
Authors: Legorreta‐Herrera M. , Mosqueda‐Romo N.A. , Hernández‐Clemente F. , Soto‐Cruz I. 
Published: November 2013

AbstractWe selected diabetes mellitus for this laboratory exercise to provide students with an explicit model for scientific research concerning the association between the R230C polymorphism and susceptibility to type 2 diabetes mellitus, which is highly prevalent in the Mexican population. We used a collaborative project‐based learning to engage students to direct their own learning process. Students worked in small groups with the same learning goal to research, organize data, and present seminars to experimentally genotype the C230 variant and correctly interpret their results. At the conclusion of this laboratory exercise, the students were able to demonstrate a clear understanding of the relevant biological molecular principles to genotype the C230 variant, showed technical competency to carry out the experimental protocols with proficiency, and interpret their results using statistical analyses. The students discussed their understanding of the genetic technologies and the broader social and ethical implications of the research. A randomly selected team was trained to work as a “sentinel” to monitor their classmates and ensure the proper application of techniques. Moreover, the evaluation of this exercise is shared between the students and the instructors; the students evaluate their own work and the performance of their classmates. At the end of the course, the students complete a questionnaire to anonymously provide feedback and information regarding their perception of the learning outcomes. Overall, the student feedback was positive, indicating that the exercise was useful and that it would help to prepare the students for professional practice. © 2013 by The International Union of Biochemistry and Molecular Biology, 41(6):409–418, 2013
Molecular mechanics and dynamics characterization of an in silico mutated protein: A stand‐alone lab module or support activity for in vivo and in vitro analyses of targeted proteins
Authors: Chiang Harry , Robinson Lucy C. , Brame Cynthia J. , Messina Troy C. 
Published: November 2013

AbstractOver the past 20 years, the biological sciences have increasingly incorporated chemistry, physics, computer science, and mathematics to aid in the development and use of mathematical models. Such combined approaches have been used to address problems from protein structure–function relationships to the workings of complex biological systems. Computer simulations of molecular events can now be accomplished quickly and with standard computer technology. Also, simulation software is freely available for most computing platforms, and online support for the novice user is ample. We have therefore created a molecular dynamics laboratory module to enhance undergraduate student understanding of molecular events underlying organismal phenotype. This module builds on a previously described project in which students use site‐directed mutagenesis to investigate functions of conserved sequence features in members of a eukaryotic protein kinase family. In this report, we detail the laboratory activities of a MD module that provide a complement to phenotypic outcomes by providing a hypothesis‐driven and quantifiable measure of predicted structural changes caused by targeted mutations. We also present examples of analyses students may perform. These laboratory activities can be integrated with genetics or biochemistry experiments as described, but could also be used independently in any course that would benefit from a quantitative approach to protein structure–function relationships. © 2013 by The International Union of Biochemistry and Molecular Biology, 41(6):402–408, 2013
Over The Counter Drugs (and Dietary Supplement) Exercise: A Team‐Based Introduction to Biochemistry for Health Professional Students
Authors: Phadtare Sangita , Abali Emine , Brodsky Barbara 
Published: November 2013

AbstractFor successful delivery of basic science topics for health‐professional students, it is critical to reduce apprehension and illustrate relevance to clinical settings and everyday life. At the beginning of the Biochemistry course for Physician Assistants, a team‐based assignment was designed to develop an understanding of the mechanism of action, effectiveness, and toxicity of five common over the counter (OTC) drugs and dietary supplements, and place these familiar medicines in a political and historical context. The objectives of this exercise were to stimulate interest in biochemistry; to provide basic information on enzymes and enzyme inhibitors related to these drugs to be expanded upon later in the course; and to encourage active and interactive learning. Teams of five students were formed, and each student was given an information sheet on aspirin, alpha‐galactosidase, orlistat, dextromethorphan, or simvastatin, a low dose statin, which was previously available without prescription at pharmacies in the UK. After each member of the team acquired information on one OTC drug/dietary supplement by reading an assigned information sheet, the team was asked to go through a series of questions, and then submit answers to a quiz as a group. A high rate of success on the quiz, an overwhelmingly positive response on formal course evaluations, and enthusiastic exchanges during class suggested this team‐based session accomplished its goals. © 2013 by The International Union of Biochemistry and Molecular Biology, 41(6):384–387, 2013
Continuous In Vitro evolution of a ribozyme ligase: A model experiment for the evolution of a biomolecule
Authors: Ledbetter Michael P. , Hwang Tony W. , Stovall Gwendolyn M. , Ellington Andrew D. 
Published: November 2013

AbstractEvolution is a defining criterion of life and is central to understanding biological systems. However, the timescale of evolutionary shifts in phenotype limits most classroom evolution experiments to simple probability simulations. In vitro directed evolution (IVDE) frequently serves as a model system for the study of Darwinian evolution but produces noticeable phenotypic shifts in a matter of hours. An IVDE demonstration lab would serve to both directly demonstrate how Darwinian selection can act on a pool of variants and introduce students to an essential method of modern molecular biology. To produce an IVDE demonstration lab, continuous IVDE of a T500 ribozyme ligase population has been paired with a fluorescent strand displacement reporter system to visualize the selection of improved catalytic function. A ribozyme population is taken through rounds of isothermal amplification dependent on the self‐ligation of a T7 promoter. As the population is selectively enriched with better ligase activity, the strand displacement system allows for the monitoring of the population's ligation rate. The strand displacement reporter system permits the detection of ligated ribozyme. Once ligated with the T7 promoter, the 5′ end of the ribozyme displaces paired fluorophore‐quencher oligonucleotides, in turn, generating visible signal upon UV light excitation. As the ligation rate of the population increases, due to the selection for faster ligating species, the fluorescent signal develops more rapidly. The pairing of the continuous isothermal system with the fluorescent reporting scheme allows any user, provided with minimal materials, to model the continuous directed evolution of a biomolecule. © 2013 by The International Union of Biochemistry and Molecular Biology, 41(6):433–442, 2013
Tibio‐pedal arterial minimally invasive retrograde revascularization in patients with advanced peripheral vascular disease: The TAMI technique, original case series
Authors: Mustapha J.A. , Saab Fadi , McGoff Theresa , Heaney Carmen , Diaz‐Sandoval Larry , Sevensma Matthew , Karenko Barbara 
Published: November 2013

BackgroundA tibial‐pedal access method is needed for patients with advanced peripheral artery disease (PAD) unable to tolerate common femoral artery (CFA) access and intervention due to body habitus or comorbidities. This is the first case series reporting an alternative technique to revascularize such patients. Using ultrasound (US) and the tibio‐pedal arterial minimally invasive retrograde revascularization (TAMI) technique, operators accessed, and revascularized the lower extremity completely via tibial‐pedal arterial access.MethodsThis retrospective, single‐center, case series recorded on 23 patients who underwent TAMI revascularization during a seven‐month period in 2012, demonstrating the feasibility and safety of the TAMI technique. Eighty‐three percent had Rutherford Classification IV–VI. Ultrasound guidance aided all tibial access. Demographics, vascular symptoms, disease characteristics, success, procedure length, time to discharge, immediate and 30‐day complications were collected. Comparison was sought with 201 unmatched patients treated via traditional CFA access over a similar period.ResultsArterial access was successful in all patients. Thirty‐six lesions were treated. Lesion success (ability to cross lesion and achieve post treatment stenosis <30%) was achieved in 95% of patients. 25% of lesions were above the knee. Average prestenosis was 92.5%; average poststenosis 12%. No major complications were noted. Two patients presented within 30 days with access site pain. Access site peroneal artery pseudo‐aneurysms were diagnosed and treated percutaneously with covered stents. Both recovered with no sequelae.ConclusionRetrograde tibio‐pedal intervention appears to be safe and effective. The TAMI technique offers an alternate revascularization method for critically ill advanced PAD patients. © 2013 Wiley Periodicals, Inc.
Significance of the learning curve in left atrial appendage occlusion with two different devices
Authors: Cruz‐Gonzalez Ignacio , Perez‐Rivera Angel , Lopez‐Jimenez Rosana , Rodriguez‐Collado Javier , Martín‐Moreiras Javier , Cascon Manuel , Arribas Antonio , Gomez Jose Carlos , Maree Andrew O. , Martin‐Luengo Candido 
Published: November 2013

ObjectiveTo evaluate the impact of learning on outcome with use of two different left atrial appendage (LAA) occlusion devices.BackgroundTwo self‐expanding devices, the Watchman and the Amplatzer Cardiac Plug (ACP), have been used for LAA occlusion in the last few years. It has been demonstrated that complications associated with implantation decrease in frequency with operator experience. However, the role of operator experience has not been compared across the two device types.MethodsThe study comprises 31 consecutive patients who underwent LAA occlusion. We compare the first 10 patients in whom an ACP was implanted with the subsequent eleven patients who underwent ACP implantation and with 10 cases where a Watcthman device was implanted. The composite safety end point comprised procedure‐related events and excessive bleeding events. We also performed 3 months echocardiographic and clinical follow‐up.ResultsThere were not significant differences in the basal clinical and echocardiographical characteristics across the three groups. Cardiac complications only occurred in the ACP initial experience group (9% vs. 0% vs. 0% P = 0.04). Echocardiographic and clinical follow‐up at 3 months was completed in all patients. No significant residual leak was detected. One patient in the ACP initial experience group developed a thrombus on the device. One patient in ACP late experience presented an ischemic stroke.ConclusionsComplications associated with LAA occlusion cluster early in the peri‐procedural period and significantly decrease in frequency with operator experience. Initial experience gained with one of device may improve outcome with use of alternative LAA occlusion devices. © 2013 Wiley Periodicals, Inc.
The impact of regulatory approval and Medicare coverage on outcomes of carotid stenting
Authors: Gray William A. , Verta Patrick 
Published: November 2013

BackgroundCarotid artery stenting (CAS) was introduced in the United States nearly a decade ago as a novel treatment of severe carotid stenosis. Voluminous and high‐quality prospective data permit analysis of longitudinal trends in CAS outcomes.MethodsOutcomes from all prospective trials with the Food and Drug Administration (FDA) oversight from 2000–2011 were reviewed, as were the subset of studies using a single CAS system. All studies shared common inclusion/exclusion criteria, endpoints, independent assessment/adjudication of neurological events, and were conducted in accordance with FDA regulations. Death and stroke (DS) rates from FDA‐approved studies in high‐surgical‐risk patients were assessed.ResultsBetween 2000 and 2011, two distinct periods with clustered and differentiated outcomes in CAS IDE trials were observed, separated by FDA approval and Centers for Medicare and Medicaid Services (CMS) coverage in 2004–2005. The mean 30‐day DS rate in the first wave (2000–2004) of CAS trials was 5.3% (95% CI: 4.6–6.2%), and fell significantly to 2.6% (95% CI: 1.9–3.7%; P = 0.0001) in the second wave (2006–2011). This decline occurred during a simultaneous, independent 24‐fold increase in monitored CAS activity. This decline in DS rates was observed in symptomatic and asymptomatic patients, alike independent of device tested.ConclusionsDeclines in periprocedural DS rates in CAS appear linked to regulatory and coverage approvals leading to increased operator experience along with continued regulatory oversight, and provide insight into the introduction of other novel therapies. © 2013 Wiley Periodicals, Inc.
Subdivisions and connectional networks of the lateral prefrontal cortex in the macaque monkey
Authors: Saleem Kadharbatcha S. , Miller Brad , Price Joseph L. 
Published: November 2013

ABSTRACTNeuroanatomical studies have long indicated that corticocortical connections are organized in networks that relate distinct sets of areas. Such networks have been emphasized by development of functional imaging methods for correlating activity across the cortex. Previously, two networks were recognized in the orbitomedial prefrontal cortex, the “orbital” and “medial” networks (OPFC and MPFC, respectively). In this study, three additional networks are proposed for the lateral prefrontal cortex: 1) a ventrolateral network (VLPFC) in and ventral to the principal sulcus; 2) a dorsal network (DPFC) in and dorsal to the principal sulcus and in the frontal pole; 3) a caudolateral network (CLPFC) in and rostral to the arcuate sulcus and the caudal principal sulcus. The connections of the first two networks are described here. Areas in each network are connected primarily with other areas in the same network, with overlaps around the principal sulcus. The VLPFC and DPFC are also connected with the OPFC and MPFC, respectively. Outside the prefrontal cortex, the VLPFC connects with specific areas related to somatic/visceral sensation and vision, in the frontoparietal operculum, insula, ventral bank/fundus of the superior temporal sulcus, inferior temporal gyrus, and inferior parietal cortex. In contrast, the DPFC connects with the rostral superior temporal gyrus, dorsal bank of the superior temporal sulcus, parahippocampal cortex, and posterior cingulate and retrosplenial cortex. Area 45a, in caudal VLPFC, is unique, having connections with all the networks. Its extrinsic connections resemble those of the DPFC. In addition, it has connections with both auditory belt/parabelt areas, and visual related areas. J. Comp. Neurol. 522:1641–1690, 2014. © 2013 Wiley Periodicals, Inc.
Connectivity of somatosensory cortical area 1 forms an anatomical substrate for the emergence of multifinger receptive fields and complex feature selectivity in the squirrel monkey (Saimiri sciureus)
Authors: Ashaber Mária , Pálfi Emese , Friedman Robert M. , Palmer Cory , Jákli Balázs , Chen Li Min , Kántor Orsolya , Roe Anna W. , Négyessy László 
Published: November 2013

ABSTRACTConverging evidence shows that interaction of digit‐specific input, which is required to form global tactile percepts, begins as early as area 3b in the primary somatosensory cortex with the involvement of intrinsic lateral connections. How tactile processing is further elaborated in area 1, the next stage of the somatosensory cortical hierarchy, is less understood. This question was investigated by studying the tangential distribution of intrinsic and interareal connections of finger representations of area 1. Retrogradely labeled cell densities and anterogradely labeled fibers and terminal patches were plotted and quantified with respect to the hand representation by combining tract tracing with electrophysiological mapping and intrinsic signal optical imaging in somatosensory areas. Intrinsic connections of distal finger pad representations of area 1 spanned the representation of multiple digits indicating strong cross‐digit connectivity. Area 1 distal finger pad regions also established high‐density connections with homotopic regions of areas 3b and 2. Although similar to area 3b, connections of area 1 distributed more widely and covered a larger somatotopic representation including more proximal parts of the finger representations. The lateral connectivity pattern of area 1 is a suitable anatomical substrate of the emergence of multifinger receptive fields, complex feature selectivity, and invariant stimulus properties of the neurons. J. Comp. Neurol. 522:1769–1785, 2014. © 2013 Wiley Periodicals, Inc.
PKG in honey bees: Spatial expression, Amfor gene expression, sucrose responsiveness, and division of labor
Authors: Thamm Markus , Scheiner Ricarda 
Published: November 2013

ABSTRACTDivision of labor is a hallmark of social insects. In honey bees, division of labor involves transition of female workers from one task to the next. The most distinct tasks are nursing (providing food for the brood) and foraging (collecting pollen and nectar). The brain mechanisms regulating this form of behavioral plasticity have largely remained elusive. Recently, it was suggested that division of labor is based on nutrition‐associated signaling pathways. One highly conserved gene associated with food‐related behavior across species is the foraging gene, which encodes a cyclic guanosine monophosphate (cGMP)‐dependent protein kinase (PKG). Our analysis of this gene reveals the presence of alternative splicing in the honey bee. One isoform is expressed in the brain. Expression of this isoform is most pronounced in the mushroom bodies, the subesophageal ganglion, and the corpora allata. Division of labor and sucrose responsiveness in honey bees correlate significantly with foraging gene expression in distinct brain regions. Activating PKG selectively increases sucrose responsiveness in nurse bees to the level of foragers, whereas the same treatment does not affect responsiveness to light. These findings demonstrate a direct link between PKG signaling in distinct brain areas and division of labor. Furthermore, they demonstrate that the difference in sensory responsiveness between nurse bees and foragers can be compensated for by activating PKG. Our findings on the function of PKG in regulating specific sensory responsiveness and social organization offer valuable indications for the function of the cGMP/PKG pathway in many other insects and vertebrates. J. Comp. Neurol. 522:1786–1799, 2014. © 2013 Wiley Periodicals, Inc.
Longitudinal in vivo two‐photon fluorescence imaging
Authors: Crowe Sarah E. , Ellis‐Davies Graham C.R. 
Published: November 2013

ABSTRACTFluorescence microscopy is an essential technique for the basic sciences, especially biomedical research. Since the invention of laser scanning confocal microscopy in the 1980s, which enabled imaging both fixed and living biological tissue with 3D precision, high‐resolution fluorescence imaging has revolutionized biological research. Confocal microscopy, by its very nature, has one fundamental limitation. Due to the confocal pinhole, deep tissue fluorescence imaging is not practical. In contrast (no pun intended), two‐photon fluorescence microscopy allows, in principle, the collection of all emitted photons from fluorophores in the imaged voxel, dramatically extending our ability to see deep into living tissue. Since the development of transgenic mice with genetically encoded fluorescent protein in neocortical cells in 2000, two‐photon imaging has enabled the dynamics of individual synapses to be followed for up to 2 years. Since the initial landmark contributions to this field in 2002, the technique has been used to understand how neuronal structure are changed by experience, learning, and memory and various diseases. Here we provide a basic summary of the crucial elements that are required for such studies, and discuss many applications of longitudinal two‐photon fluorescence microscopy that have appeared since 2002. J. Comp. Neurol. 522:1708–1727, 2014. © 2013 Wiley Periodicals, Inc.
Organization and cellular arrangement of two neurogenic regions in the adult ferret (Mustela putorius furo) brain
Authors: Takamori Yasuharu , Wakabayashi Taketoshi , Mori Tetsuji , Kosaka Jun , Yamada Hisao 
Published: November 2013

ABSTRACTIn the adult mammalian brain, two neurogenic regions have been characterized, the subventricular zone (SVZ) of the lateral ventricle (LV) and the subgranular zone (SGZ) of the dentate gyrus (DG). Despite remarkable knowledge of rodents, the detailed arrangement of neurogenic regions in most mammals is poorly understood. In this study, we used immunohistochemistry and cell type‐specific antibodies to investigate the organization of two germinal regions in the adult ferret, which belongs to the order Carnivora and is widely used as a model animal with a gyrencephalic brain. From the SVZ to the olfactory bulb, doublecortin‐positive cells tended to organize in chain‐like clusters, which are surrounded by a meshwork of astrocytes. This structure is homologous to the rostral migratory stream (RMS) described in other species. Different from rodents, the horizontal limb of the RMS emerges directly from the LV, and the anterior region of the LV extends rostrally and reached the olfactory bulb. In the DG, glial fibrillary acidic protein‐positive cells with long radial processes as well as doublecortin‐positive cells are oriented in the SGZ. In both regions, doublecortin‐positive cells showed characteristic morphology and were positive for polysialylated‐neural cell adhesion molecule, beta‐III tubulin, and lamin B1 (intense staining). Proliferating cells were detected in both regions using antibodies against proliferating cell nuclear antigen and phospho‐histone H3. These observations demonstrate that the two neurogenic regions in ferrets have a similar cellular composition as those of other mammalian species despite anatomical differences in the brain. J. Comp. Neurol. 522:1818–1838, 2014. © 2013 Wiley Periodicals, Inc.