cssi/SciSciGPT-SciSciNet huggingface dataset:
BRCA1/BRCA2 Germline Mutations in Locally Recurrent Breast Cancer Patients After Lumpectomy and Radiation Therapy: Implications for Breast-Conserving Management in Patients With BRCA1/BRCA2 Mutations

PURPOSE: Breast cancer patients treated conservatively with lumpectomy and radiation therapy (LRT) have an estimated lifetime risk of local relapse (ipsilateral breast tumor recurrence [IBTR]) of 10% to 15%. For breast cancer patients carrying BRCA1 or BRCA2 (BRCA1/2) mutations, the outcome of treatment with LRT with respect to IBTR has not been determined. In this study, we estimate the frequency of BRCA1/2 mutations in a study of breast cancer patients with IBTR treated with LRT. PATIENTS AND METHODS: Between 1973 and 1994, there were 52 breast cancer patients treated with LRT who developed an IBTR within the prior irradiated breast and who were willing to participate in the current study. From our database, we also identified 52 control breast cancer patients treated with LRT without IBTR. The control patients were individually matched to the index cases with respect to multiple clinical and pathologic parameters. Lymphocyte DNA specimens from all 52 locally recurrent patients and 15 of the matched con...
Expression of the oncogene of avian reticuloendotheliosis virus in Escherichia coli and identification of the transforming protein in reticuloendotheliosis virus T-transformed cells.

Abstract The genome of reticuloendotheliosis virus T (REV-T) includes a unique oncogene v-rel, which is transcribed in low amounts into a 3.0-kilobase subgenomic mRNA in REV-T-transformed lymphoid cells. To identify the v-rel protein, REV-T DNA sequences were cloned into bacterial plasmid vectors designed to achieve expression of foreign DNA sequences in Escherichia coli. Portions of the v-rel gene were joined to the 5' segment of the trpE gene. Upon induction of trpE with indoleacrylic acid, large amounts of trpE-v-rel fusion proteins were produced by the bacteria carrying these recombinant plasmids. Two trpE-v-rel fusion proteins were synthesized in E. coli, which collectively represent three-quarters of the predicted v-rel protein. Polyclonal antisera were generated to trpE-v-red fusion proteins. These antisera were used in immunoblotting experiments to identify a 57-kDa v-rel protein in REV-T-transformed lymphoid cells lines and REV-T-infected chicken embryo fibroblast cultures. The v-rel gene expressed in E. coli under lac control was found to produce a 56-kDa protein. Although REV-T-transformed and Marek disease virus-transformed lymphoid cells contain c-rel mRNA transcripts, a c-rel protein could not be detected with antisera directed against v-rel fusion proteins.
Resolution of Multiple Substrate Binding Sites in Cytochrome P450 3A4: The Stoichiometry of the Enzyme−Substrate Complexes Probed by FRET and Job's Titration†

To explore the mechanism of homotropic cooperativity in human cytochrome P450 3A4 (CYP3A4) we studied the interactions of the enzyme with 1-pyrenebutanol (1-PB), 1-pyrenemethylamine (PMA), and bromocriptine by FRET from the substrate fluorophore to the heme, and by absorbance spectroscopy. These approaches combined with an innovative setup of titration-by-dilution and continuous variation (Job's titration) experiments allowed us to probe the relationship between substrate binding and the subsequent spin transition caused by 1-PB or bromocriptine or the type-II spectral changes caused by PMA. The 1-PB-induced spin shift in CYP3A4 reveals prominent homotropic cooperativity, which is characterized by a Hill coefficient of 1.8 +/- 0.3 (S50 = 8.0 +/- 1.1 microM). In contrast, the interactions of CYP3A4 with bromocriptine or PMA reveal no cooperativity, exhibiting KD values of 0.31 +/- 0.08 microM and 7.1 +/- 2.3 microM, respectively. The binding of all three substrates monitored by FRET in titration-by-dilution experiments at an enzyme:substrate ratio of 1 reveals a simple bimolecular interaction with KD values of 0.16 +/- 0.09, 4.8 +/- 1.4, and 0.18 +/- 0.09 microM for 1-PB, PMA, and bromocriptine, respectively. Correspondingly, Job's titration experiments showed that the 1-PB-induced spin shift reflects the formation of a complex of the enzyme with two substrate molecules, while bromocriptine and PMA exhibit 1:1 binding stoichiometry. Combining the results of Job's titrations with the value of KD obtained in our FRET experiments, we demonstrate that the interactions of CYP3A4 with 1-PB obey a sequential binding mechanism, where the spin transition is triggered by the binding of 1-PB to the low-affinity site, which becomes possible only upon saturation of the high-affinity site.
Biomedical relation extraction using stochastic difference equations

We propose an unsupervised method for extracting causal relations between biomedical entities using stochastic difference equations (SDE). Our method attempts to generalize the propagation of relevance in medical sentences in order to extract related biomedical terms and the semantic relation between them. We model the propagation of relevance in candidate medical sentences through the use of stochastic difference equations. The equation of propagation of relevance helps in identifying the most relevant medical terms in a causal sentence. It also increases the accuracy of Information Extraction as it allows to set a threshold for the minimum relevance for relation extraction.
Habit as an explanation of participation in an online peer-production community

User activities in peer-production communities have mainly been examined under the assumption that individuals are rational individuals who are always cognizant of what they are doing and why. We argue that not all use is the same; while some behaviors are governed by conscious motivations, others may be a habitual response that is developed out of routine. We take a more granular approach to explaining what people are doing in online communities and how motivations and habits explain their use of specific features. In the context of the peer-production community Everything2 we employ both server log data and self-report, finding that habit is a non-conscious-driven behavior that is more associated with less cognitively-demanding tasks than content production.
Peptide composition of Sindbis virus variants

The peptide composition of variants of Sindbis virus which differ in plaque-type, elution pattern from calcium phosphate columns and virulence in mice was analyzed. Differences in peptide number or composition were not detected in these variants. Since the Sindbis virion has an outer lipoprotein envelope which is derived at least in part from the plasma membrane of the host cell, peptide composition of purified chicken embryo membranes was analyzed. In contrast to the virions, the number of peptide units in the host cell membrane were too numerous to give resolution.
Autoimmune progesterone urticaria

Abstract Two patients with urticaria occurring at the mid- and premenstrual part of the cycle are reported. Evidence incriminating progesterone as the cause of urticaria includes production of lesions with the administration of exogenous progesterone, inhibition of urticaria with inhibition of ovulation, positive skin tests with progesterone, passive cutaneous transfer, and the demonstration by immunofluorescence of antibodies reactive to the luteinizing cells of the corpus luteum.
Sample-Based Bayesian Accident Reconstruction

In accident reconstruction, information derived from samples of crash tests can on occasion replace subjective prior information reflecting expert opinion. A method for accomplishing this, based on a straightforward application of Bayesian reasoning as used in statistics, is applied to three-accident scenarios: estimating critical speeds from yaw marks, estimating impact speed from crush, and estimating impact speed from pedestrian throw distance. The method is evaluated by comparing the estimates to measurements obtained in crash tests. In almost all cases the measured speeds were captured by the posterior 95% credible intervals.
Particle velocity measurements with macroscopic fluorescence imaging in lymph tissue mimicking microfluidic phantoms

Ultrasound poroelastography can quantify structural and mechanical properties of tissues such as stiffness, compressibility, and fluid flow rate. This novel ultrasound technique is being explored to detect tissue changes associated with lymphatic disease. We have constructed a macroscopic fluorescence imaging system to validate ultrasonic fluid flow measurements and to provide high resolution imaging of microfluidic phantoms. The optical imaging system is composed of a white light source, excitation and emission filters, and a camera with a zoom lens. The field of view can be adjusted from 100 mm x 75 mm to 10 mm x 7.5 mm. The microfluidic device is made of polydimethylsiloxane (PDMS) and has 9 channels, each 40 μm deep with widths ranging from 30 μm to 200 μm. A syringe pump was used to propel water containing 15 μm diameter fluorescent microspheres through the microchannels, with flow rates ranging from 0.5 μl/min to 10 μl/min. Video was captured at a rate of 25 frames/sec. The velocity of the microspheres in the microchannels was calculated using an algorithm that tracked the movement of the fluorescent microspheres. The imaging system was able to measure particle velocities ranging from 0.2 mm/sec to 10 mm/sec. The range of flow velocities of interest in lymph vessels is between 1 mm/sec to 10 mm/sec; therefore our imaging system is sufficient to measure particle velocity in phantoms modeling lymphatic flow.
Transition Regions in the Cope Rearrangement of 1,5-Hexadiene and Its Cyano Derivatives

Substituent effects on the mechanism of the Cope rearrangement were studied by computing C2h (Cs) cuts through the potential energy surface (PES) for the reaction of 1,5-hexadiene and its di-, tri-, and tetracyano derivatives at the (U)B3LYP/6-31G* and (U)BPW91/6-31G* levels. The stabilization of substituted structures along the cuts is discussed in terms of the energies of isodesmic formation from allyl radicals and acetonitrile molecules. Cyano groups at C1, C3, and C5 provide a nearly additive stabilization of each point along the Cs cut even though their influence on the geometry is competitive. Evaluation of the density of effectively unpaired electrons at various geometries indicates that the radical character of a transition state (TS) is not altered by radical stabilizing substituents as such but depends solely on the interallylic bond length. Although the UB3LYP diyl intermediate for the parent compound is plausible when compared to the lowest triplet PES, neither MRPT2 at the UB3LYP geometries n...
Preservation of Permeability Barrier Ontogenesis in the Intrauterine Growth-Retarded Fetal Rat

ABSTRACT: The epidermal permeability barrier is provided by intercellular lipids forming multiple membrane bilayers in the stratum corneum. In the fetal rat, the barrier to transepidermal water loss forms during the 20th d of gestation and is accompanied by 1) increasing stratum corneum thickness;2) increasing stratum corneum lipid content, particularly nonpolar ceramide and cholesterol content; and3) the formation of lamellar unit structures throughout the stratum corneum interstices. In this report, we demonstrate that among pups of 20 d gestational age increasing barrier competence is correlated with increasing fetal weight. It has been previously demonstrated that fetal rats subjected to intrauterine growth retardation (IUGR) exhibit a thinner stratum corneum and decreased content of differentiation-specific epidermal structural proteins. To determine whether IUGR fetal rats also exhibit immaturity of barrier function and the barrier membrane system, maternal rats underwent unilateral uterine vessel ligation on d 17 or 18 of gestation and IUGR and control littermates were harvested on d 20, 21, or 22 of gestation for determination of transepidermal water loss. Despite significant somatic growth retardation and a thinner stratum corneum, barrier function in IUGR fetal rats did not significantly differ from that in control littermates at any gestational age. In both IUGR and control fetal rat epidermis at 21 d gestational age, lipids were deposited in a membrane pattern as visualized by nile red fluorescence microscopy and formed lamellar unit membrane structures throughout the stratum corneum intercellular domains as observed by electron microscopy. Stratum corneum lipid content was reduced in IUGR pups relative to surface area (μg lipid/cm2) but was preserved relative to its structural protein content (μg lipid/mg dry weight). Thus, IUGR in the fetal rat does not delay development of a competent barrier or maturation of the barrier membrane system.
Classical conditioning in the rat fetus: temporal characteristics and behavioral correlates of the conditioned response.

This study examined the temporal characteristics and behavioral correlates of the conditioned response (CR) following classical conditioning of the embryonic Day 20 (E20 rat fetus). The conditioning procedure involved pairing of an artificial nipple (the CS) with an infusion of milk (the US) to establish classical conditioning. The test for classical conditioning involved measurement of a stimulus-evoked facial wiping response in a classical conditioning test. Experiment 1 compared the effectiveness of one- and three-trial procedures to establish classical conditioning. Experiment 2, 3, and 4 described the time course for the CR following one- and three-trial conditioning procedures. Experiments 3b and 4b describe the behavioral responses to (a) presentation of the CS at the time of conditioning, (b) infusion of the milk US at the time of conditioning, and (c) reexposure to the CS before the test for classical conditioning. Experiments 5 and 6 exposed the fetus to manipulations that either increased or decreased stretching (a behavior found to be associated with the CR). The results are discussed in terms of the temporal characteristics and behavioral correlates of conditioned and unconditioned responses and their mediation by activity in endogenous mu and kappa opioid systems.
High-Performance LWIR MBE-Grown HgCdTe/Si Focal Plane Arrays

We have been actively pursuing the development of long-wavelength infrared (LWIR) HgCdTe grown by molecular beam epitaxy (MBE) on large-area silicon substrates. The current effort is focused on extending HgCdTe/Si technology to longer wavelengths and lower temperatures. The use of Si versus bulk CdZnTe substrates is being pursued due to the inherent advantages of Si, which include available wafer sizes (as large as 300 mm), lower cost (both for the substrates and number of die per wafer), compatibility with semiconductor processing equipment, and the match of the coefficient of thermal expansion with silicon read-out integrated circuit (ROIC). Raytheon has already demonstrated low-defect, high-quality MBE-grown HgCdTe/Si as large as 150 mm in diameter. The focal plane arrays (FPAs) presented in this paper were grown on 100 mm diameter (211)Si substrates in a Riber Epineat system. The basic device structure is an MBE-grown p-on-n heterojunction device. Growth begins with a CdTe/ZnTe buffer layer followed by the HgCdTe active device layers; the entire growth process is performed in␣situ to maintain clean interfaces between the various layers. In this experiment the cutoff wavelengths were varied from 10.0 μm to 10.7 μm at 78 K. Detectors with >50% quantum efficiency and R0A ∼1000 Ohms cm2 were obtained, with 256 × 256, 30 μm focal plane arrays from these detectors demonstrating response operabilities >99%.
Asymptomatic left main coronary artery disease in the Coronary Artery Surgery Study (CASS) registry.

Left main coronary artery disease (i.e., greater than or equal to 50% stenosis) was found in 1,477 of 20,137 patients in the Coronary Artery Surgery Study (CAS) registry. Of these patients, 53 (3.6%) were asymptomatic. Asymptomatic and symptomatic patients were similar in regard to 1) severity of left main coronary artery stenosis (67% vs. 70%), 2) extent of proximal coronary artery disease (no differences in number of or severity of proximal stenoses), 3) left ventricular end-diastolic pressure (13 mm Hg vs. 14 mm Hg), 4) left ventricular wall motion score 9.1 vs. 8.7), and 5) number of coronary artery segments with greater than 70% stenosis (4.4 vs. 4.8). Among the asymptomatic patients, 47% received medical and 49% received surgical treatment. In the symptomatic group, 20% received medical and 78% received surgical therapy. The survival rate 5 years after surgery for treatment of left main coronary artery stenosis was 84% for the symptomatic patients and 88% for the asymptomatic patients (p = NS). Medical management of left main coronary artery disease produced a 5-year survival rate of 57% for asymptomatic patients and 58% for symptomatic patients. Within the asymptomatic subgroup, 88% of those surgically treated survived 5 years, whereas only 57% of those medically treated survived 5 years (p = 0.02). Thus, for CASS patients with left main coronary artery disease, the percentage of those that were asymptomatic is low (3.6%); asymptomatic and symptomatic patients with left main coronary artery disease had no significant difference in severity of left main coronary artery stenosis, extent of overall coronary artery disease, or left ventricular function.(ABSTRACT TRUNCATED AT 250 WORDS)
Airbreathing hypersonic vehicle design and analysis methods and interactions

Abstract The design and analysis of airbreathing hypersonic vehicles is discussed. Individual discipline methods as well as the extensive interactions among the disciplines are described. Examples of the use of HOLIST, a framework currently in development to modularly integrate the analysis methods for use in design and optimization, are given along with plans for further development.
Analysis of the modulation of transcriptional activity in myelopoiesis and leukemogenesis.

Acute myeloid leukemia (AML) is still associated with a mortality of 60 to 80%. AML is characterized by a block in myeloid differentiation. The transcription factors PU.1 and C/EBPalpha are responsible for normal myeloid differentiation from stem cells to monocytes or granulocytes. In particular, PU.1 induces expression of the macrophage colony-stimulating factor (M-CSF) receptor and the development of monocytes, whereas C/EBPalpha increases the expression of the granulocyte colony-stimulating factor (G-CSF) receptor and leads to mature granulocytes. In AML, chromosomal aberrations result in oncoproteins such as AML1/ETO, PML/RARalpha, or activated Ras, which can deregulate genes important for normal myelopoiesis. Thus, AML1/ETO can bind to the transcription factor C/EBPalpha, inhibit C/EBPalpha-dependent transcription, and block granulocytic differentiation. However, AML1/ETO can also synergize with the transcription factor AML1 to enhance the activity of the M-CSF receptor promoter. On the other hand, the PML/RARalpha fusion protein causes transcriptional repression by recruiting the nuclear corepressor (N-CoR) histone deacetylase complex to the DNA, which results in decreased histone acetylation and a repressive chromatin organization. Here we describe methods to investigate whether and how signaling agonists induce myeloid differentiation and how oncoproteins might cause AML by modulating the activity of transcription factors that are pivotal for normal myeloid development.
Methacholine-induced cutaneous flare response: bivariate analysis of responsiveness and sensitivity

Cutaneous reactions to allergens exhibit a sigmoid dose-response relationship. Available methods for evaluating the allergen skin-test response do not adequately account for the sigmoid curve. Methodologic factors handicap quantitative studies of allergens based on skin-test reactivity. This problem was evaluated with a pharmacologic agonist that mimics cutaneous reactivity. Epicutaneous tests with appropriate concentrations of methacholine were used to provoke flare responses in 84 healthy subjects. A novel hyperbolic tangent model of the sigmoid dose-response curve was used to estimate responsiveness (R) as the midpoint of the sigmoid curve. Sensitivity (C) was estimated as the agonist concentration yielding a flare response equivalent to R. Estimates of sensitivity were independent of estimates of responsiveness (r=-0.0565, p=0.6642). The geometric mean methacholine sensitivity among health subjects was 287 mM/L, and average methacholine responsiveness was 4.9 mm. The mathematic model used in these studies fitted observations surprisingly well (X2(84)=37.044, p greater than 0.95). Differences in methacholine sensitivity and responsiveness related to race, sex, and allergic and/or vasomotor tendencies were detected but were subtle and did not account for a significant portion of the variation among healthy subjects. This model may provide a useful method for quantifying cutaneous immediate hypersensitivity reactions in patients.
Differentiation of ischemic from nonischemic cardiomyopathy with positron emission tomography

This study was undertaken to determine whether positron emission tomography (PET) performed after the intravenous injection of 11C-palmitate permits differentiation of patients with ischemic from those with nonischemic dilated cardiomyopathy. PET was performed after intravenous injection of 11C-palmitate in 10 patients with ischemic and in 10 with nonischemic dilated cardiomyopathy. Regions of homogeneously severely depressed accumulation of 11C-palmitate, representing 15% or more of the expected myocardial cross-sectional area, were observed in 8 of 10 patients with ischemic but in none of 10 patients with nonischemic cardiomyopathy. Patients with nonischemic cardiomyopathy had marked spatial heterogeneity of the accumulation of palmitate throughout the left ventricular myocardium, whereas most tomographic sections from patients with ischemic cardiomyopathy accumulated 11C-palmitate more homogeneously in regions exclusive of discrete defects indicative of remote infarction. Thus, a larger number of discrete noncontiguous regions (17 ± 5 compared with 12 ± 4, p < 0.001) and greater reduction of average 11C-palmitate content (59 ± 6 compared with 64 ± 10% maximal myocardial radioactivity, p < 0.05) were seen in the tomographic reconstructions from patients with nonischemic than in those from patients with ischemic cardiomyopathy. These findings support the hypothesis that multiple myocardial infarctions underlie the process seen as dilated cardiomyopathy in patients with coronary artery disease. Our findings indicate that PET permits differentiation of patients with ischemic from those with nonischemic cardiomyopathy.
Effects of microsolvation on the adenine-uracil base pair and its radical anion: adenine-uracil mono- and dihydrates.

Microhydration effects upon the adenine−uracil (AU) base pair and its radical anion have been investigated by explicitly considering various structures of their mono- and dihydrates at the B3LYP/DZP++ level of theory. For the neutral AU base pair, 5 structures were found for the monohydrate and 14 structures for the dihydrate. In the lowest-energy structures of the neutral mono- and dihydrates, one and two water molecules bind to the AU base pair through a cyclic hydrogen bond via the N9−H and N3 atoms of the adenine moiety, while the lowest-lying anionic mono- and dihydrates have a water molecule which is involved in noncyclic hydrogen bonding via the O4 atom of the uracil unit. Both the vertical detachment energy (VDE) and adiabatic electron affinity (AEA) of the AU base pair are predicted to increase upon hydration. While the VDE and AEA of the unhydrated AU pair are 0.96 and 0.40 eV, respectively, the corresponding predictions for the lowest-lying anionic dihydrates are 1.36 and 0.75 eV, respectively....
Portal vein gas following air-contrast barium enema in granulomatous colitis: Report of a case

Portal vein gas developed in a patient with granulomatous colitis following air-contrast barium enema. No symptomatology or morbidity could be attributed to the portal vein gas in this patient.
Studies on isolated islets of Langerhans (Brockmann bodies) of teleost fishes. II. Evidence for insulin biosynthesis in vitro.

Abstract Isolated islet tissue of toadfish ( Opsanus tau ) has been incubated in vitro and the incorporation of radioactive substrates into islet tissue protein has been studied. Using 14 C-labeled substrates, high specific activities were found in insulin which was purified from crude extracts by a combination of paper chromatography, isoelectric precipitations and cellulose adsorption. The highest specific activity of insulin labeled with 14 C achieved in these studies was 5.7·10 5 counts/min/mg. The biologic activity of this preparation was 7.7 units/mg. Using [ 14 C]isoleucine as radioactive substrate, preferential labeling of the A chain of insulin could be demonstrated, as would be expected from the absence of isoleucine from the B chain.
Acculturation of Asian Indian Sojourners in America: Application of the Cultivation Framework

This study examined the influence of watching American television on the acculturation levels of Asian Indian sojourners utilizing tenets of cultivation theory. Consumption of Indian print media an...
Comparison of the characteristics of the negative inotropic actions of dinitrophenol, rotenone, antimycin A and the intracellular calcium antagonist, propyl-methylenedioxyindene.

Abstract 1. 1. The characteristics of the reversal of the comparable negative inotropic actions of 10 −4 M propyl-methylenedioxyindene (an intracellular calcium antagonist), 3 × 10 −5 M dinitrophenol (an uncoupler of mitochondrial oxidative phosphorylation), 10 −6 M rotenone (a site I mitochondrial respiratory chain poison) and 3 × 10 −6 M antimycin A (a site II mitochondrial respiratory chain poison) were studied in the isolated, electrically-paced guinea-pig left atrium. 2. 2. The negative inotropic effect of propyl-methylenedioxyindene was more sensitive to reversal by 5 mM calcium and 10 −9 –10 −7 M isoproterenol than were the comparable negative inotropic effects of dinitrophenol, rotenone and antimycin A. 3. 3. These results indicate that the negative inotropic effect of propyl-methylenedioxyindene is not exerted through inhibition of mitochondrial electron transport nor through uncoupling of mitochondrial oxidative phosphorylation.
Measuring scars of periodic orbits.

The phenomenon of periodic orbit scarring of eigenstates of classically chaotic systems is attracting increasing attention. Scarring is one of the most important ``corrections'' to the ideal random eigenstates suggested by random matrix theory. This paper discusses measures of scars and in so doing also tries to clarify the concepts and effects of eigenfunction scarring. We propose a universal scar measure which takes into account an entire periodic orbit and the linearized dynamics in its vicinity. This measure is tuned to pick out those structures which are induced in quantum eigenstates by unstable periodic orbits and their manifolds. It gives enhanced scarring strength as measured by eigenstate overlaps and inverse participation ratios, especially for longer orbits. We also discuss off-resonance scars which appear naturally on either side of an unstable periodic orbit.
RNA Regulatory Elements and Polyadenylation in Plants

Alternative poly(A) site choice (also known as alternative polyadenylation, or APA) has the potential to affect gene expression in qualitative and quantitative ways. APA may affect as many as 82% of all expressed genes in a plant. The consequences of APA include the generation of transcripts with differing 3'-UTRs (and thus differing regulatory potential) and of transcripts with differing protein-coding potential. Genome-wide studies of possible APA suggest a linkage with pre-mRNA splicing, and indicate a coincidence of and perhaps cooperation between RNA regulatory elements that affect splicing efficiency and the recognition of novel intronic poly(A) sites. These studies also raise the possibility of the existence of a novel class of polyadenylation-related cis elements that are distinct from the well-characterized plant polyadenylation signal. Many potential APA events, however, have not been associated with identifiable cis elements. The present state of the field reveals a broad scope of APA, and also numerous opportunities for research into mechanisms that govern both choice and regulation of poly(A) sites in plants.
Epilepsy in Children With Delayed Presentation of Perinatal Stroke

A subgroup of children with perinatal stroke do not present clinically until after the perinatal period. Detailed epilepsy outcomes in these children have not been well studied. A retrospective cohort study of 45 children with delayed presentation of perinatal stroke identified by review of pediatric stroke clinic records, physician referral, and International Classification of Diseases, Ninth edition, code searches of hospital records, was performed at a tertiary pediatric hospital in Indianapolis, Indiana. A modified version of the Engel scale was used to grade epilepsy outcomes. The chi(2) test, Fisher's exact test, and relative risks were calculated to examine the association of epilepsy at time of last follow-up with initial presentation with seizures, infantile spasms, radiographic findings, and initial abnormal electroencephalogram (EEG). These tests were also used to examine the association of epilepsy with cognitive or motor disability and the association of initial abnormal EEG with motor disability. Patients presented with hemiparesis (40; 89%), seizures (4; 9%), or headaches (1; 2%). All had unilateral infarcts on cranial imaging. Four children (9%) had infantile spasms, 2 at presentation and 2 later. Nineteen children received at least 1 EEG for suspicious spells or frank seizures; initial EEG was abnormal in 16 patients (84%). At last follow-up, 17 patients (38%) had epilepsy, which was severe in 4 (24% of those with epilepsy). Initial presentation with seizures (relative risk = 3.2; 95% confidence interval, 2.0-4.9) and infantile spasms (relative risk = 3.2; confidence interval, 2.0-4.9) were associated with epilepsy at last follow-up. Infantile spasms were also associated with moderate-to-severe epilepsy at last follow-up (relative risk = 10.3; confidence interval, 1.9-54.4). Epilepsy at last follow-up was associated with cognitive disability (P = .05). Initial abnormal EEG was not associated with cerebral palsy (P = .30). Epilepsy is frequent in children with delayed presentation of perinatal stroke and is associated with initial presentation with seizures and infantile spasms at any point in time. Cognitive disability often accompanies epilepsy in these children.
Sensitive determination of sugars utilizing packed capillary columns and electron capture detection

Abstract A sensitive method is described for carbohydrate analysis in the picomole range. Methanolysis and trifluoroacetylation were employed to generate methyl N,O-trifluoroacetyl glucosides of sugars, which were separated by gas chromatography on 7 m x 0.5 mm packed capillary columns and quantitated by an electron capture detector. Sample transfer steps are avaoided by performing both methanolysis and trifluoroacetylation in a single capillary tube. Routine analyses of α 1 -acid glycoprotein, fetuin, and carcinoembryonic antigen have been achieved with amounts as low as 0.1 μg of glycoprotein.
Two distinct human DNA diesterases that hydrolyze 3′-blocking deoxyribose fragments from oxidized DNA

Abstract Mammalian cells were investigated for enzymes that help correct oxidative damages in DNA. We focused on 3'-repair diesterases, which process DNA ends at oxidative strand breaks by removing 3'-blocking fragments of deoxyribose that prevent DNA repair synthesis. Two enzymes were found in a variety of mouse, bovine and human tissues and cultured cells. The two activities were purified to differing degrees from HeLa cells. One enzyme had the properties of the known HeLa AP endonuclease (Mr approximately 38,000, with identical substrate specificity and reaction requirements, and cross-reactivity with anti-HeLa AP endonuclease antiserum) and is presumed identical to that protein. The second activity did not interact with anti-HeLa AP endonuclease antibodies and had relatively less AP endonuclease activity. This second enzyme may have been detected in other studies but never characterized. In addition to the 3'-repair diesterase and AP endonuclease, this partially purified preparation also harbored DNA 3'-phosphatase and 3'-deoxyribose diesterase activities. It is unknown whether all activities detected in the second preparation are due to a single protein, although activity against undamaged DNA was not detected. The in vivo roles of these two widely distributed 3'-repair diesterase/AP endonucleases have not been determined, but with the characterizations presented here such questions may now be focused.
Digital Detection Techniques for Dynamic Optical Tomographic Imaging

In this paper we present a novel application of digital detection and data-acquisition techniques to a prototype dynamic optical tomography system. The core component is a digital signal processor (DSP) that is responsible for collecting and processing the digitized data set. Utilizing the processing power of the DSP, real-time data rates for this 16-source, 32-detector system, can be achieved at rates as high as 140Hz per tomographic frame. Many of the synchronously-timed processes are controlled by a complex programmable logic device (CPLD) that is used in conjunction with the DSP to orchestrate data flow. The operation of the instrument is managed through a comprehensive graphical user interface, which was designed using the LabVIEW software package. Performance analysis demonstrates very low system noise (~.60pW RMS noise equivalent power) and excellent signal precision (<0.1%) for most practical cases. First experiments on tissue phantoms show that dynamic behavior can be accurately captured using this system.
Pulmonary macrophage antimicrobial activity in canine endotoxin shock and lung injury.

Bacterial sepsis and pneumonia are common complications of lung injury and predispose the host to a poor resolution. We studied the functional integrity of pulmonary macrophages derived from minced lung preparations in a canine model of endotoxin-induced shock with acute lung injury. Dogs given 2 mg/kg of Escherichia coli endotoxin 055:B5 developed classic shock symptoms with concomitant acute lung injury; control animals given saline showed no physiological or pathological abnormalities. Compared to previous work with this canine model, the lung injury in this extended time period (6 h) had progressed to include alveolar edema. Six hours after endotoxin infusion, the left lung was lavaged, perfused, and the resulting lung minced for isolation of pulmonary macrophages. The endotoxic-model pulmonary macrophages showed several significant functional differences from controls. Although they elicited greater production of H2O2 (p < 0.05), both phagocytosis of radiolabeled Staphylococcus aureus and E. coli (p ...
Electron–photon equation of motion with application to the Lamb shift

An equation of motion (EOM) is proposed for the electron which includes the effect of the radiation field on the electron's motion. The new EOM – the electron–photon EOM (EPEOM) – is the same as Dirac's equation with the ‘bare’ or mechanical mass replaced by a complex electromagnetic mass whose real part is interpreted as the observed mass of the electron. The Lamb shift is calculated from the difference of the EPEOM energy and the Dirac-equation energy.
Mathematical descriptions of hybridoma culture kinetics. III. Simulation of fed-batch bioreactors

Abstract The growth rate profiles of fed-batch hybridoma cultures were simulated using mathematical descriptions developed and presented in previous papers. Comparison of the simulation with an experimental fed-batch culture of the hybridoma ATCC-CRL-1606 producing anti-fibronectin indicated that accurate predictions of the growth rate profile were attained only if the simulation model included: (a) degradation of serum activity; and (b) a time lag in the response of the growth rate to shifts in the medium composition. This lag was independently characterized from transient growth responses of batch cultures subjected to sudden shifts in the serum and ammonium levels. The transient regions were modeled as first order responses with 8 to 18 h dead times. Also critical to the simulation was the accurate prediction of the specific cellular death rate, which was shown to be a function of the observed growth rate. The mathematical relation developed to accurately characterize the death rate constant of CRL-1606 hybridomas was found to apply to other hybridoma cell lines described in the literature. The success of this simulation suggests that mathematical descriptions developed by the methods outlined in this and previous papers may be utilized to determine optimal bioreactor design and control for the commercial production of mammalian cell products. Indeed, control theory was invoked to determine the optimal control policy of the fed-batch culture presented in this paper and was responsible for more than a ten-fold increase in the cell and antibody yield from serum compared to standard batch cultures. All of the process variables in the fed-batch culture were accurately predicted, except the antibody concentration. This resulted from the inability to accurately predict the specific productivity for a given culture due to passage-to-passage variability.
Gender differences in outcomes of arteriovenous fistulas in hemodialysis patients

Gender differences in outcomes of arteriovenous fistulas in hemodialysis patients. Background The prevalence of arteriovenous (A-V) fistula use is lower among female than male hemodialysis patients. This difference may be due, in part, to smaller vessel diameter in women. However, even when routine preoperative vascular mapping is used to select vessels with suitable diameters, fistulas are still less likely to mature in women than in men. Methods To explore the reasons for this gender discrepancy, we evaluated the outcomes of 230 A-V fistulas placed at our institution after preoperative mapping. Vessel diameters, radiologic and surgical interventions, and fistula adequacy for dialysis were assessed. Results Fistula adequacy for dialysis was lower in women than men (31 vs. 51%, P = 0.001). The inferior outcome of fistulas in women was observed for both forearm fistulas (18 vs. 43%, P = 0.02) and upper arm fistulas (39 vs. 60%, P = 0.04). Differences in vessel diameter did not explain the lower patency rate of fistulas among women. Among fistulas not lost due to technical failure or early thrombosis, 31% underwent one or more interventions (salvage procedures) due to failure to mature. These interventions included angioplasty, ligation of tributaries, superficialization, and surgical revision of the anastomosis. A salvage procedure was more likely in women than in men (42 vs. 23%, P = 0.04). The likelihood of fistula maturation after an intervention was similar among women and men (50 vs. 37%, P = 0.40). Salvage procedures increased the proportion of adequate fistulas to a greater degree in women than in men (relative increases of 68 and 15%, respectively). Conclusions These data suggest that fistulas are less likely to be useable for dialysis in women than in men, despite routine preoperative mapping and frequent interventions undertaken to salvage immature fistulas.
Evaluation of a rat model for the study of local regulation of intestinal blood flow: ex vivo asanguineous perfusion of the ileal vascular bed.

Abstract A new model of ex vivo vascularly perfused, isolated rat ileum was developed and evaluated. Segments of distal ileum (approximately 5 cm) from male Wistar rats were isolated on their vascular pedicles. Perfusion through an aortic cannula with oxygenated (95% O2, 5% CO2) Krebs solution containing 5% bovine albumin, 5.6 mM glucose, and 25 mM mannitol at 37°C was initiated immediately after interruption of blood flow. The bowel preparations, including the abdominal aorta, were then transferred to a perfusion chamber. Perfusion pressure was maintained by gravity at 40 mm Hg. Flow was measured with an electromagnetic flow probe. The portal vein, together with the lymphatics, drained freely into collection tubes. The bowel lumen was perfused at 0.85 ml/min with isotonic modified Krebs solution containing [14C]polyethylene glycol, and the luminal perfusion pressure was monitored. Luminal effluents were collected through a large-bore outlet tubing. As determined by histology, O2 consumption, vascular reactivity, and mucosal permeability, the preparations were viable for at least 60 min of perfusion. With this model, a vasoconstrictor effect of the α2-adrenoceptor agonist clonidine was documented for the first time in isolated rat bowel.
Effect of Verification Bias on the Sensitivity of Fecal Occult Blood Testing: a Meta-Analysis

OBJECTIVES There is controversy regarding the sensitivity of fecal occult blood tests (FOBT) for detecting colorectal cancer. Many of the published studies failed to correct for verification bias which may have increased the sensitivity.
Endoplasmic reticulum calcium pool depletion-induced apoptosis is coupled with activation of the death receptor 5 pathway

Endoplasmic reticulum calcium pool depletion-induced apoptosis is coupled with activation of the death receptor 5 pathway
Influence of pressure, salinity, temperature and grain size on silica diagenesis in quartzose sandstones

Abstract Based on calculated quartz solubilities for near-neutral pH conditions in the 1–6-km depth range, there is a suggested predictable affect of pressure, temperature and salinity on pressure solution in quartzose sandstones. The following results were obtained: 1. (1) Quartz solubility related to increasing grain-contact pressure with depth is ∼ 7 times greater at 4 km than at 1 km ( m s = 1.5 · 10 −3 or 90 ppm vs. 2.0 · 10 −4 or 12 ppm, respectively). 2. (2) The difference between solubilities at grain contact and hydrostatic pressures increases with depth, excluding overpressuring (at 1 km Δm s = 1.0 · 10 −6 or 0.06 ppm; at 4 km Δm s = 4.7 · 10 −5 or 2.8 ppm; and at 6 km Δm s = 2.2 · 10 −4 or 13.0 ppm). 3. (3) Increasing pore-fluid salinity decreases solubility of quartz regardless of depth (e.g., at 3 km and m NaCl = 3, m s = 8.9 · 10 −4 or 54 ppm; at 3 km and m NaCl = 6, m s = 7.5 · 10 −4 or 45 ppm). 4. (4) Temperature has the greatest influence on quartz solubility of any parameter studied. Both high heat flow and high geothermal gradient enhance quartz solubility (e.g., at 1 km and 50°C, m s = 2.0 · 10 −4 or 12 ppm; at 4 km and 140°C, m s = 1.5 · 10 −3 or 90 ppm). These results indicate that pressure solution, as well as local and non-local migration and reprecipitation of silica, and thus reservoir quality destruction in quartzose sandstones, should be enhanced under higher temperature conditions, where grain-contact pressure is near lithostatic and pore-fluid salinity is low. Under conditions of low temperature, high pore-fluid salinity and grain-contact pressure close to hydrostatic, pressure solution is discouraged and higher reservoir quality more likely preserved. Grain-size differences in quartzose sandstones also influence pressure solution. For very fine-, fine- and medium-grained sand laminae, the average pressure solution index is about 3.3, 2.5 and 2 times that of coarse sand.
Noninvasive high-speed optical imaging of biochemical interactions in microfluidic devices

Microfluidic devices are finding more and more applications ranging from chemical analysis to biological and chemical microreactors, replacing bulky devices and sparkling new applications. he ability to monitor in situ the transitional changes of chemical and structural composition becomes an important issue for the continuing advancement and successful implementation of this new technology, directing its manufacturing and exploring the new areas of its applications. In this report we consider nonlinear optical methods, such as third-harmonic-generation microscopy and nonlinear Raman microscopy for noninvasive, chemically and structurally sensitive diagnostics of biochemical interactions in microfluidic devices.
Novel conical microstructures created in silicon with femtosecond laser pulses

Summary form only given. Silicon wafers are mounted inside a vacuum chamber backfilled with gas and then irradiated with 800-nm pulses from a regeneratively amplified Ti:sapphire laser. Following laser treatment, the samples are removed from the chamber and analyzed with a scanning electron microscope (SEM).
Hypertension and the cardiometabolic syndrome--is it the blood pressure lowering or the blood pressure medication that is important?

Perspectives of Hypertension in CMS focuses on the role hypertension plays in the metabolic syndrome. Keith C. Ferdinand, MD, Section Editor, welcomes submissions from clinicians and researchers of clinical commentaries, case studies, and medical images specifically related to hypertension and diabetes. For information on submissions for the column, see Information for Authors at www.lejacq.com. Elevated blood pressure and the cardiometabolic syndrome are often difficult clinical challenges specifically related to fusing appropriate lifestyle modifications and antihypertensive agents. This case illustrates some of the factors clinicians have utilized in approaching patients with this common but challenging clinical situation.
Outcomes after endoscopic dacryocystorhinostomy without mucosal flap preservation.

BackgroundThe purpose of this study was to evaluate outcomes of powered endoscopic dacryocystorhinostomy (DCR) without the preservation of mucosal flaps for the management of acquired nasolacrimal ...
Hypotheses tests for variance components in some multivariate mixed models

Abstract A multivariate mixed model involving exactly one random effect is considered and a locally best invariant (LBI) test is derived for testing the significance of the multivariate variance component corresponding to the random effect. For balanced models, the likelihood ratio test (LRT) is also derived for the same testing problem. In general, the LBI test is different from Pillai's trace test, except for balanced models. The standard multivariate tests based on Wilk's Λ, Pillai's trace and Roy's maximum root are also valid tests for this problem and simulated powers of these tests and the LBI test are reported for several bivariate unbalanced one-way random models. As expected, the LBI test has some advantage over the others for local alternatives. For several bivariate balanced one-way random models, simulation results are also given on the power of the LRT and the tests based on Wilk's Λ, Pillai's trace and Roy's maximum root in order to compare these tests.
Constructive irrational space

The Frechet combination allows the construction of a complete metric on the set of irrational numbers. The constructive study of the resulting spaceM was begun by Errett Bishop. This paper studies the structure ofM in some detail. The constructive approach requires a strong form of the concept of irrational number and particular attention to the distinctions between the various notions of points exterior to a set. The main results are the characterization and construction of all compact and locally compact subspaces ofM.
HYPEROXEMIA AND INCREASED MORTALITY IN PREMATURES

Records of 159 premature infants with the following criteria were reviewed: BW 750 - 1500 g, no malformations, survival at least 24 hours. The highest PO2 value for each infant from routine blood gas determinations was selected and tabulated as to survival: This unexpected effect was largely independent from the associated alveolar-arterial O2, gradient or FiO2. For patients with A-aDO2 140 mm Hg were less mature and included more with resuscitation, anemia, RDS, intracranial hemorrhage, PDA, and there were more late deaths. Among the explanations for this phenomenon are the possibilities that hyperoxemia triggers fatal pathological processes and that hyperoxemia signifies a labile ventilation/perfusion relationship.