bluuebunny/crossref_metadata_2025_split huggingface dataset:
Atypical Memory B Cells Are Greatly Expanded in Individuals Living in a Malaria-Endemic Area
Authors: Weiss Greta E. , Crompton Peter D. , Li Shanping , Walsh Laura A. , Moir Susan , Traore Boubacar , Kayentao Kassoum , Ongoiba Aissata , Doumbo Ogobara K. , Pierce Susan K. 
Published: July 2009

Abstract
Epidemiological observations in malaria endemic areas have long suggested a deficiency in the generation and maintenance of B cell memory to Plasmodium falciparum (Pf) in individuals chronically reinfected with the parasite. Recently, a functionally and phenotypically distinct population of FCRL4+ hyporesponsive memory B cells (MBCs) was reported to be expanded in HIV-infected individuals with high viral loads. In this study, we provide evidence that a phenotypically similar atypical MBC population is significantly expanded in Pf-exposed Malian adults and children as young as 2 years of age as compared with healthy U.S. adult controls. The number of these atypical MBCs was higher in children with chronic asymptomatic Pf infections compared with uninfected children, suggesting that the chronic presence of the parasite may drive expansion of these distinct MBCs. This is the first description of an atypical MBC phenotype associated with malaria. Understanding the origin and function of these MBCs could be important in informing the design of malaria vaccines.
Assessment of quality of data provided on Pap test requisitions: Implications for quality of care and patient safety
Authors: Naryshkin Sonya , Schultz Brenda L. 
Published: July 2009

Background:
The reliability of patient history and clinical information on Pap test requisitions has been questioned but not previously objectively determined. The effect of incomplete/inaccurate information on quality of patient care has not been previously quantified. Our objectives were (1) to find out how clinicians and their assistants viewed the requisition slip, and whether they understood the reasons for supplying the information requested, (2) to measure the completeness and accuracy of information on the requisition slips, and (3) to determine whether the clinical information and patient history provided on Pap test requisitions could be relied upon to accurately assign a Pap test to the laboratory's “high-risk rescreen” pool.

Methods:
Clinicians and their assistants were surveyed. A total of 899 consecutive Pap test requisition slips were reviewed. Patient history and clinical information from the slips were compared to data from our laboratory information system and/or electronic patient medical records.

Results:
Most survey respondents felt that proper completion of requisitions was important, but only 17% of clinicians and less staff realized that negative high-risk Pap tests underwent a quality assurance rescreen. Clinicians and/or staff recorded the last menstrual period, specimen source, and clinical information on the requisition slips 96%, 97%, and 88% of the time, respectively. Of 695 Pap tests with applicable computerized records, 172 (25%) qualified for high-risk rescreen based upon information provided on the requisition slip alone. An additional 52 Pap tests (7%), or 23% of the total high-risk Pap tests were discovered to be of high risk only after review of the electronic records.

Conclusions:
Clinicians and staff were receptive to discussions concerning the completion of requisition slips, but laboratory expectations could be better communicated. Requisition slips were properly completed with a high frequency, but the check boxes did not elicit all the information expected, so revision was necessary. The high accuracy of the completion of requisition slips permitted 77% of high-risk Pap tests to be identified via the requisition slip alone. Our findings challenge the conventional anecdotal impressions of “notoriously unreliable” information on Pap test requisition slips, but our experience may not be applicable to other settings.
Theoretical Evaluation of the Global and Local Electrophilicity Patterns to Characterize Hetero Diels‐Alder Cycloaddition in the Synthesis of Isoxazolo[4,5‐e](1,2,3,4‐tetrazine)
Authors: SHARMA Pratibha , KUMAR Ashok , SINGH Jitendra , SAHU Vinita 
Published: July 2009

AbstractA series of substituted dienophiles 1–10 and three 1,2‐diazadienes namely D‐1, D‐2, D‐3 were chosen to understand the reactivity and selectivity of Diels‐Alder cycloaddition. The global and local electrophilicity patterns have been evaluated on a series of cycloaddition reactions to assess the reaction pathways (NDAC/IEDDAC) using the absolute scale of electrophilicity proposed by Parr et al. Regional electrophilicity at the active sites of the reagents involved in Diels‐Alder processes has been described on a quantitative basis using local or regional electrophilicity index i.e. Fukui function. Good qualitative/quantitative comparison was found between molecular energy gaps and global electronic parameters, which has been employed to assess the cycloaddition pathways successfully.
Synthesis and Crystal Structures of Four Metal(II) Complexes with 1‐(4‐Hydroxyphenyl)‐5‐mercaptotetrazole Ligand
Authors: ZHANG Shuguang , FENG Yunlong 
Published: July 2009

AbstractTetrazolic acid, CN4H, has similar acidity to carboxylic acid group, COOH. 1‐(4‐Hydroxyphenyl)‐5‐mercaptotetrazole (H2L) can act as a monodentate (S or N) or a bidentate (N, N or N, S) ligand, forming coordination compounds with metal ions. Four new M(II) complexes with HL− ligands, Co(HL)2(Py)2(H2O)2 (1), [Mn(HL)2(H2O)4]·2H2O (2), Mn(HL)2(Phen)2 (3), and [Zn(HL)2(Phen)2]·0.5H2O·1.5CH3OH (4) have been synthesized and structurally determined by X‐ray structure analyses. Among these complexes, the M(II) centers are all six‐coordinated in an octahedral coordination geometry, and HL− ligands bond to M(II) centers via nitrogen atoms in 1 and 2, while via sulfur atoms in 3 and 4, respectively.
Electrochemical Sensor for Oxidation of NO Based on Au‐Pt Nanoparticles Self‐assembly Film
Authors: XIE Jia , YU Zhihui , XIA Dingguo 
Published: July 2009

AbstractAu‐Pt bimetallic nanoparticles film used as an efficient electrochemical sensor was prepared by self‐assembled Au‐Pt bimetallic nanoparticles on a glassy carbon (GC) substrate using thioglycolic acid as a linker. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) showed that the Au‐Pt nanoparticles self‐assembly film was dense and uniform. Electrochemical experiments revealed that Au‐Pt bimetallic nanoparticles film/GC electrode showed high electrocatalytic activity to the oxidation of nitric oxide.
Theoretical Study on Structures and Properties of N2O···HOCl Complexes
Authors: YUAN Ku , LIU Yanzhi , MA Weichao , TANG Huian , ZHU Yuancheng , ZHANG Ji 
Published: July 2009

AbstractB3LYP/6‐311++G∗︁∗︁ and MP2/6‐311++G∗︁∗︁ calculations were used to analyze the interaction between hypochlorous acid (HOCl) and nitrous oxide (N2O). The results showed that there are six and four equilibrium geometries at the B3LYP/6‐311++G∗︁∗︁ and MP2/6‐311++G∗︁∗︁ computational levels, respectively. The equilibrium geometries of S1 and S3 were confirmed to be transition states by analytical frequency computations, and the other equilibrium geometries as minima. Complexes of S3, S5 and S6 use the H(6) atom of HOCl as a proton donor and the terminal O(3) atom of N2O as an acceptor. However, S2 uses the terminal N(1) atom of N2O as an acceptor. As for S1 and S4, S1 uses the Cl(4) atom of HOCl as a proton donor and the terminal N(1) atom of N2O as an acceptor; S4 uses the terminal O(3) atom of N2O as an acceptor. Interaction energy of the complexes corrected with basis set superposition error (BSSE) lies in the range of −1.56–−8.73 kJ·mol−1 at the B3LYP/6‐311++G∗︁∗︁ levels. The natural bond orbit (NBO) and atoms in molecules (AIM) theory were also applied to explain the structures and the properties of the complexes.
Classification of Rat FTIR Colon Cancer Data Using Wavelets and BPNN
Authors: CHENG Cungui , XIONG Wei , TIAN Yumei 
Published: July 2009

AbstractA feature extracting method based on wavelets for horizontal attenuated total reflectance Fourier transform infrared spectroscopy (HATR‐FTIR) and the cancer classification using artificial neural network trained with back‐propagation algorithm is presented. The FTIR data collected from 36 normal Sprague‐dawley (SD) rats, 60 1,2‐DMH‐induced SD rats, and 44 second generation rats of those induced rats were first preprocessed. Then, 12 feature variants were extracted using continuous wavelet analysis. Based on BPNN classification, all spectra were classified into two categories: normal and abnormal ones. The accuracy values of identifying normal, dysplastic, early carcinoma, and advanced carcinoma were 100%, 94%, 97.5%, and 100%, respectively. This result indicated that FTIR with continuous wavelet transform (CWT) and the back‐propagation neural network (BPNN) could effectively and easily diagnose colon cancer in its early stages.
Three‐component Synthesis of Homoallylic Amines Catalyzed by Phosphomolybdic Acid in Water
Authors: XIE Zhengfeng , LI Guilong , ZHAO Gang , WANG Jide 
Published: July 2009

AbstractThe three‐component reactions of aromatic aldehydes, amines and allyltributylstannane in water catalyzed by phosphomolybdic acid (PMA), underwent smoothly to afford the corresponding homoallylic amines in high yields at room temperature.
Enantioselective Direct Aldol Reactions Catalyzed by Cinchonine‐derived Prolinamides
Authors: ZHAO Jing , CHEN Aijun , LIU Quanzhong 
Published: July 2009

AbstractHighly enantioselective aldol reactions catalyzed by cinchonine‐derived prolinamides are reported. Both cyclic and acyclic ketones were reacted with various aldehydes furnishing the desired aldol products in up to 90% yield with excellent enantioselectivities (up to 95%) and moderate diastereoselectivities (up to 3.6/1) in the case of cyclic ketones. A possible mechanism that elucidates the excellent observed enantioselectivities is presented.
Effect of Electronic Factor in Ru‐phosphine‐diamine Complexes on Selective Hydrogenation of CC and CO Bonds
Authors: ZHANG Yu , YU Xiaojun , YU Changbin , XIA Yuqing , LI Ruixiang , CHEN Hua , LI Xianjun 
Published: July 2009

AbstractA series of ruthenium complexes bearing different phosphines and diamines were synthesized and their components and structures were characterized by NMR spectra and elemental analyses. The catalytic properties of these complexes for the hydrogenation of benzylideneacetone and the mixture of acetophenone and styrene were investigated. The results showed that the basicity increase of phosphine or diamine dramatically facilitates the hydrogenation activity and selectivity to CO double bond. On the contrary, the basicity decrease of phosphine or diamine not only slows down the catalytic activity, but also significantly suppresses the hydrogenation selectivity to CO double bond. Based on the effect of electron factors of these complexes on the hydrogenation activity and selectivity of benzylideneacetone and the mixture of styrene and acetophenone, the activation mechanism of dihydrogen in ruthenium‐phosphine‐diamine system was proposed.
One‐step Preparation and Antibacterial Property of Poly(N‐iso‐propyl‐acrylamide) Grafted Poly(acrylonitrile/styrene) Microspheres Immobilized with Silver Nanoparticles
Authors: FENG Jiao , FAN Liheng , CHU Hong , XIONG Wanbin , JIANG Jinqiang , CHEN Mingqing 
Published: July 2009

AbstractMonodispersed silver nanoparticles were immobilized onto the surface of poly(N‐isopropylacrylamide) grafted poly(acrylonitrile/styrene) (PNIPAAm‐g‐PAN/PSt) microspheres by a one‐step method using AgNO3 as a silver source. This process was performed via the coordination interaction between Ag+ ions and amide groups on PNIPAAm‐g‐PAN/PSt microsphere surfaces with the reduction of the corresponding ions by ethanol taking place simultaneously. Fourier transform infrared (FTIR) spectroscopy and ultraviolet (UV)‐visible spectra illustrated that the silver nanoparticles were successfully immobilized onto the PNIPAAm‐g‐PAN/PSt microspheres. The size and morphology of silvered microspheres were characterized by transmission electron microscopy (TEM). The weight percent of silver nanoparticles immobilized onto the microspheres was 12% based on the determination of thermogravimetric analysis (TGA). The antibacterial tests demonstrated that the as‐prepared silvered microspheres showed activity against Gram‐negative bacteria.
Design, Synthesis and Anti‐HIV Integrase Evaluation of 1,2,3‐ Triazol‐4‐yl‐substituted 1,4‐Dihydro‐4‐oxo‐1,5‐napthyridine‐ 3‐carboxylic Acids
Authors: ZENG Jia , LÜ Xiuhua , ZENG Chengchu , HU Liming , ZHONG Rugang 
Published: July 2009

AbstractCopper(I)‐catalyzed terminal alkyne‐azide 1,3‐cycloaddition reaction has emerged as one of the main strategies for the rapid creation and screening of a small molecular library. The present work describes the design and synthesis of a series of 1,2,3‐triazol‐4‐yl‐substituted 1,4‐dihydro‐4‐oxo‐1,5‐napthyridine‐3‐carboxylic acids in which the hydrophobic and hydrophilic domains were efficiently incorporated by a click reaction. The structures of the desired products 8 and 12 were characterized by spectroscopic methods and their HIV integrase inhibitory activities were also screened.
A quantitative relationship of electrocardiographic criteria of left ventricular hypertrophy with echocardiographic left ventricular mass: A multivariate approach
Authors: Kansal S. , Roitman D. I. , Sheffield L. T. 
Published: July 2009

AbstractThe purpose of this study was to evaluate the sensitivity of various electrocardiographic (EKG) criteria of left ventricular hypertrophy (LVH) in relation to echocardiographic left ventricular mass (LVME) and to assess the relative strength of various EKG variables used in the diagnosis of LVH by multivariate analysis. An attempt was also made to determine if a new combination of precordial and T‐wave voltage could improve the sensitivity of EKG. In 89 patients, M‐mode echocardiograms and standard EKGs were studied. Correlation of Romhilt‐Estes point‐score system with LVME was r = 0.621, sensitivity and specificity was 57 and 81%, respectively. Other voltage criteria had lower sensitivity. Various combinations of precordial and T‐wave voltage were not superior. The quantitative relationship of individual EKG variable, QRS duration, SV1‐3, R V4‐6, strain T wave, left atrial abnormality, intrinsicoid deflection and axis, with LVM was, r = 0.661,0.595,0.429, 0.42, 0.347, and 0.225, respectively. By multivariate analysis, QRS duration, S V1‐3, T‐wave and R V4‐6 voltage had F‐value (relative strength) of 27.95, 27.15, 22.02, and 4.03, respectively, other variables were statistically insignificant. In conclusion, the most important EKG variables predictive of LVH are QRS duration, S V1‐3, strain T‐wave and lateral voltage in decreasing value. Rescoring these variables in accordance to their correlation to LVM may improve EKG sensitivity for the diagnosis of LVH.
The effect of radiographic contrast agents on bleeding time and platelet aggregation
Authors: Verdirame J. D. , Davis J. W. , Phillips P. E. 
Published: July 2009

AbstractThe purpose of this study was to determine whether the use of relatively small amounts of radio‐graphic contrast agents may impair hemostasis. Before and after injection of contrast agents, we measured the template bleeding time, platelet count in whole blood and platelet‐rich plasma, platelet aggregation induced by epinephrine and adenosine diphosphate (ADP), and percent disaggregation of ADP‐induced platelet aggregates in platelet‐rich plasma of 18 patients. Ten patients received 50–100 ml of sodium iothalamate (66.8%) for intravenous urography and 8 patients received 125–200 ml of a combination of meglumine diatrizoate (66%) and sodium diatrizoate (10%) for coronary an‐giography and left ventriculography. Neither group demonstrated a statistically significant mean difference (p >0.05) for any parameter measured before and after administration of the contrast agents. However, 2 patients who received diatrizoate had lengthening of their bleeding times to greater than twice the baseline value without any change in in vitro platelet aggregation. Physicians should be aware of this potential cause of bleeding which could be of particular danger to patients undergoing cardiopulmonary bypass with its inherent hemostatic defects.
Detection of a diurnal rhythm in arterial blood pressure in the evaluation of 24‐hour antihypertensive therapy
Authors: Germanó G. , Ciavarella M. , Appolloni A. , Ferrucci A. , Corsi V. , Damiani S. 
Published: July 2009

AbstractUncertainty in defining hypertensive disease makes a prolonged study of blood pressure pattern necessary, using continuous or semicontinuous blood pressure recordings. Its pathophysiological meaning involves data sufficiently indicative of blood pressure profile with reference to the continuous stimulations of different intensity and duration, which are met by subjects both in their daily activities and in the passage from an active life to sleep. Such a parameter is, in fact, an indispensable premise for a correct course of therapy. The aim of our work was at first the detection of a diurnal rhythm in blood pressure, using data obtained in a 24‐h ambulatory monitoring away from the conditioning of different activities and daily routine. We have employed three groups of 34 males each. The first group consisted of hypertensive outpatients, while hospitalized subjects comprised the second group. Thtrthird group was composed of normal subjects. Furthermore, after finding this system productive, we started studying whether this rhythm of blood pressure could be modified under the influence of a single administered drug dose, and whether information obtained could be easily interpreted. We studied 12 male patients with essential hypertension, which had been untreated. Each patient underwent three 24‐h blood pressure ambulatory monitorings. Two different doses of nifedipine (10 and 20 mg) were randomly administered to each of the patients at the beginning of the second and third readings. We observed a significant fall in systolic blood pressure and a minor decrease in diastolic blood pressure after administration of a single 10 mg nifedipine tablet.
Abnormal left ventricular filling in patients with sustained myocardial relaxation: Assessment of diastolic parameters using radionuclide angiography and echocardiography
Authors: Bryhn M. 
Published: July 2009

AbstractParameters of left ventricular filling obtained from time‐activity curves of radionuclide angiograms were compared with parameters of myocardial relaxation from digitized M‐mode curves of the free wall endocardium in 25 consecutive patients. Eight patients had normal left ventricular systolic and diastolic function. Five patients with low ejection fraction (EF < 50%) also had abnormal values of peak filling rate (PFR), time to peak filling rate (Tr), and/or time constant of endocardial retraction (Te). Twelve patients with normal EF had three (40%), two (40%), or one (20%) of the diastolic parameters within the pathological range. Tr correlated significantly with Te (r=0.88, p<0.001), and patients with Te prolongation always had high values of Tr. One of the diastolic parameters (PFR) correlated significantly with EF (r=0.60, p<0.01). Parameters of left ventricular filling and myocardial relaxation are thus abnormal in many patients with normal systolic function, indicating that diastolic parameters may be more sensitive to myocardial deterioration.
Noninvasive index of cardiac contractility during stress testing: A collaborative study
Authors: Luisada A. A. , Singhal A. , Portaluppi F. , Strozzi C. 
Published: July 2009

AbstractThe present study was conducted in parallel in three different institutions with a similar purpose but using different technical setups. Based on the experimental demonstration that the external phonocardiogram is similar to the rate of acceleration (d3P/d3t) of the left ventricular pressure, and that catecholamines in a similar way increase the early positive wave of the left ventricular pressure and the first heart sound (S1) of the external phonocardiogram; knowing that exercise causes secretion of catecholamines and sympathetic reflexes, we have studied the S1 changes as a result of exertion in 34 normal young subjects. Blood pressure, heart rate, electrocardiograph, and phonocardiograph recordings of each subject were taken. In 10 subjects, cardiac output was also recorded by impedance cardiography. The result of the study was that the first heart sound increased routinely 4–5 times the normal amplitude; in a few subjects the increase was up to 15 times greater. While the extent of increase of S1 was proportional to the severity and duration of the effort and was usually proportional to the increase of other parameters, exceptions were noted as having marked increase of S1 with moderate increase of either blood pressure or heart rate. This was explained by the different receptors activated by the catecholamines and by the complexity of hormonal and neural influences acting on various organs in a stress test. The amplitude of S1 was found to be a reasonably reliable index for following changes of cardiac contractility during exercise, and the suggestion was made that this parameter should be studied in parallel with the others in routine stress tests.
Right ventricular subendocardial infarction in a patient with pulmonary hypertension, right ventricular hypertrophy, and normal coronary arteries
Authors: Carlson E. B. , Reimer K. A. , Rankin J. S. , Peter R. H. , Mccormack K. M. , Alexander L. G. 
Published: July 2009

AbstractRight ventricular infarction is usually associated with coronary artery disease and concomitant left ventricular infarction. Isolated right ventricular subendocardial necrosis was discovered at autopsy in a 52‐year‐old woman with pulmonary hypertension, right ventricular hypertrophy, and normal coronary arteries, who died with septicemia 41 days after mitral valve replacement. This represents the first well‐documented report of isolated right ventricular subendocardial infarction associated with normal coronary arteries.
Dissection of the left main coronary artery: A complication of ptc a to the anterior descending artery
Authors: Lotan C. , Gotsman M. , Milgalter E. 
Published: July 2009

AbstractThis case report describes a patient with severe discrete left anterior descending coronary artery atheroma who underwent percutaneous transluminal coronary angioplasty. During the procedure, dissection occurred in a superior atheromatous plaque of the left main coronary artery and needed immediate surgery. Special care should be taken in the selection and angioplasty of patients with concomitant left main artery disease.
Intracardiac teratoma in a newborn
Authors: Farooki Z. Q. , Chang C. H. , Jackson W. L. , Clapp S. K. , Hakimi M. , Arciniegas E. , Pinsky W. W. 
Published: July 2009

AbstractPrimary tumors of the heart are infrequent at all ages. We present a newborn with hypoxia and a heart murmur, in whom an echocardiogram revealed a large tumor filling the right ventricle and the pulmonary annulus. To maintain pulmonary blood flow, the patency of the ductus arteriosus was achieved by infusion of prostaglandin E1. Successful surgical resection was accomplished. The pathological examination was characteristic of a benign teratoma. The patient remains asymptomatic and has shown no evidence of recurrence of the tumor during a follow‐up period of 34 months. This represents the eleventh case of intracardiac teratoma and only the fourth case to undergo successful surgical resection.