cssi/SciSciGPT-SciSciNet huggingface dataset:
Challenges and advances in mouse modeling for human pancreatic tumorigenesis and metastasis

Pancreatic cancer is critical for developed countries, where its rate of diagnosis has been increasing steadily annually. In the past decade, the advances of pancreatic cancer research have not contributed to the decline in mortality rates from pancreatic cancer—the overall 5-year survival rate remains about 5% low. This number only underscores an obvious urgency for us to better understand the biological features of pancreatic carcinogenesis, to develop early detection methods, and to improve novel therapeutic treatments. To achieve these goals, animal modeling that faithfully recapitulates the whole process of human pancreatic cancer is central to making the advancements. In this review, we summarize the currently available animal models for pancreatic cancer and the advances in pancreatic cancer animal modeling. We compare and contrast the advantages and disadvantages of three major categories of these models: (1) carcinogen-induced; (2) xenograft and allograft; and (3) genetically engineered mouse models. We focus more on the genetically engineered mouse models, a category which has been rapidly expanded recently for their capacities to mimic human pancreatic cancer and metastasis, and highlight the combinations of these models with various newly developed strategies and cell-lineage labeling systems.
Superquenching in cyanine pendant poly(L-lysine) dyes: dependence on molecular weight, solvent, and aggregation.

A series of poly(l-lysines) ranging in number of repeat units (NPRU) from 6 to 900 has been synthesized and the photophysics of the series and monomer cyanine dye have been studied in solution. In water or aqueous dimethyl sulfoxide, the oligomers and polymers exhibit high sensitivity to fluorescence quenching by oppositely charged electron acceptors; in this study, 9,10-anthraquinone-2,6-disulfonate was used as a quencher for the cationic fluorescent polyelectrolytes. Quenching constants (KSV) measured in 50:50 (v/v) dimethyl sulfoxide−water increase monotonically with increase in NPRU ranging from 630 M-1 for monomer to 1.2 × 109 M-1 for dilute solutions of the polymer having NPRU ∼ 900. The polymers having NPRU > 100 exhibit predominantly J-aggregate absorption and fluorescence and enhanced susceptibility to quenching. For the polymers exhibiting strong J-aggregation, the effective exciton domain quenched by a single quencher reaches ∼100 PRU. The results of this study permit a semiquantitative analysi...
Zhou’s aggregation theorems with multiple welfare weights

Abstract This paper extends the aggregation theorems of Zhou (1997) to incorporate a social preference for randomization. We establish variations of Harsanyi’s utilitarianism theorems for general societies in which there exists a set of welfare weights, and a maxmin rule is applied.
Cross-sectional study of the quality of life and functional disability report in young basketball athletes – a pilot study

Introducao: Com o aumento da participacao de jovens atletas em ambientes competitivos ha tambem um aumento nas ocorrencias de lesoes traumaticas e nao-traumaticas, gerando dor, disfuncao, e alteracoes na qualidade de vida desses jovens competidores. Objetivo: O objetivo desse estudo piloto foi identificar os dominios (componentes) do questionario de qualidade de vida desses atletas e avaliar se houve tambem algum nivel de incapacidade funcional. Voluntarios: Participaram dessa pesquisa 12 voluntarios do sexo masculino com 16 anos de idade. Materiais e Metodo: Coleta de dados ocorreu durante os treinos da pre-temporada com a versao traduzida para o Portugues do questionario Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) e do questionario Oswestry de Incapacidade Funcional. Esse procedimento foi repetido apos oito semanas, onde os jovens atletas se encontravam engajados em competicoes oficiais. Resultados: Considerando a qualidade de vida do time como um todo, nao foram observadas alteracoes estatisticamente significativas (p≤0,05) embora os valores apresentassem alteracoes em quase todos os dominios do questionario. O nivel de incapacidade funcional permaneceu minimo durante a competicao na amostra de atletas utilizada.
New Insights Into the Arrhythmogenic Substrate of the Long QT Syndrome

A lot has transpired in our understanding of the inherited Long QT syndrome (LQTS) since the first description of a family with prolonged QT interval, deafness, and sudden death by Jervell and Lange-Nielsen in 19571 and a similar family reported in 1958 by Levine and Woodworth.2 Several children with LQTS and sudden death without deafness were reported by Romano et al in 19633 and Ward in 1964.4 Numerous LQTS case reports were published during the next several years, and the first specific therapy for this disorder involving antiadrenergic left cervicothoracic sympathetic ganglionectomy was reported in 1971,5 with β-blocker therapy introduced a few years thereafter. The Rochester-based International LQTS Registry was initiated in 1979. Using some patients from the LQTS Registry, Keating et al6 reported linkage of LQTS to the Harvey ras-1 locus on chromosome 11 in 1991, and within a few years Keating and associates identified the genes for LQT1, 2, and 3, which ushered in the extensive LQTS genotype-phenotype studies during the last 20 years. Various clinical studies identified the duration of the …
Purification and characterization of methylmalonyl-CoA mutase from Ascaris lumbricoides

Abstract 1. 1. Methylmalonyl CoA mutase from Ascaris lumbricoides has been purified to homogeneity. The mutase is homogeneous as judged by equilibrium sedimentation and polyacrylamide gel electrophoresis. 2. 2. The worm mutase is a glycoprotein with a mol. wt of 147,000 ± 3500 composed of two identical or very similar subunits. One molecule of adenosylcobalamin is tightly bound to each subunit. 3. 3. The mutase from Ascaris is not affected by exposure to light, cyanide ion or intrinsic factor and is not inhibited by iodoacetate and p -hydroxymercuribenzoate. 4. 4. The kinetic constants of this mutase for (R,S)methylmalonyl CoA are K m = 4.2 × 10 −5 M and V max = 4.73 μ mol/mg/min.
In vitro, long-range sequence information for de novo genome assembly via transposase contiguity

.We describe a method that exploits contiguity preserving transposase sequencing (CPT-seq) to facilitate the scaffolding of de novo genome assemblies. CPT-seq is an entirely in vitro means of generating libraries comprised of 9216 indexed pools, each of which contains thousands of sparsely sequenced long fragments ranging from 5 kilobases to >1 megabase. These pools are ‘‘subhaploid,’’ in that the lengths of fragments contained in each pool sums to ~5% to 10% of the full genome. The scaffolding approach described here, termed fragScaff, leverages coincidences between the content of different pools as a source of contiguity information. Specifically, CPT-seq data is mapped to a de novo genome assembly, followed by the identification of pairs of contigs or scaffolds whose ends disproportionately co-occur in the same indexed pools, consistent with true adjacency in the genome. Such candidate ‘‘joins’’ are used to construct a graph, which is then resolved by a minimum spanning tree. As a proof-of-concept, we apply CPT-seq and fragScaff to substantially boost the contiguity of de novo assemblies of the human, mouse, and fly genomes, increasing the scaffold N50 of de novo assemblies by eight- to 57-fold with high accuracy. We also demonstrate that fragScaff is complementary to Hi-C-based contact probability maps, providing midrange contiguity to support robust, accurate chromosome-scale de novo genome assemblies without the need for laborious in vivo cloning steps. Finally, we demonstrate CPT-seq as a means of anchoring unplaced novel human contigs to the reference genome as well as for detecting misassembled sequences.
Mathematical Analysis of a Zn / NiOOH Cell

A mathematical model has been developed to predict the time dependent behavior of a Zn/NiOOH cell. The model uses experimentally determined polarization expressions to describe the losses between the positive and the negative electrodes. The electronic losses in the plane of the electrode are simulated by a network of resistors. The potential distribution, the current distribution, the cell voltage, the power capability, and the energy of a cell can be predicted. The mathematical model provides an analytical tool to evaluate, for example, the trade-offs between power capability and current collector mass, needed to design an electric vehicle battery.
Stark-shifted image potential states of benzene bilayers on Cu(1 1 0) and Cu(1 1 1)

Abstract Benzene bilayer islands were observed by STM to be structurally similar on both Cu(1 1 1) and Cu(1 1 0) surfaces. The local electronic structure of the bilayers was studied using tunneling spectroscopy of Stark-shifted image potential states. On both Cu substrates, the n = 1 bilayer state was locally shifted away from the Fermi level when compared to the n = 1 monolayer state. The Stark-shift due to the electric field of the STM tip was observed to be greater for the n = 1 bilayer state than the n = 1 monolayer state on Cu(1 1 1).
On the rapid variability of AM Herculis

New observations of the rapid brightness flickering of AM Her are presented, with 10 hours of data from three nights and with a time resolution of 1.6 s, and the statistical properties of the flickering are described. The flickering is assumed to be the superposition of bursts produced as individual clumps in the accretion flow encounter the region of strong emission just above the surface of the white dwarf at the magnetic poles. A statistical shot-noise analysis is then appropriate, and a pulse duration of 70-90 s is determined, with many pulses overlapping at any instant. The clumps must then have the form of long, thin strings as they reach the emission region.
Syllabic complexity and syntagmatic rules for syllable production–a comment on aspects of the syntax of behaviour by D. G. Mackay

Using a metric of syllabic complexity derived from a syntagmatic theory of syllabic production, in which syllabic recoding expands a syllable into an optional initial consonant group and an obligatory vowel group, MacKay (1974) examined the relationship between the complexity of syllables and their durations in a task of rapid repetition. He concluded from spectrographic measurements of the test syllables that the complexity metric was a good predictor of the syllable durations, and hence syllable repetition rates. The present report demonstrates that comparable, if not better, predictions are made by a simpler theory based on the recoding of syllable structures as series of CV combinations, with appropriate reductions of C or V segments.
Mobile Doppler Radar Observations of a Tornado in a Supercell near Bassett, Nebraska, on 5 June 1999. Part I: Tornadogenesis

Abstract This two-part paper details an analysis of high-resolution wind and reflectivity data collected by a mobile, W-band Doppler radar: The dataset captures the near-surface life history of a tornado in a supercell in north-central Nebraska on 5 June 1999. The formation of the tornado vortex near the ground is described from a sequence of sector scans ranging from 30-s intervals prior to tornadogenesis to 10–15-s intervals during much of the lifetime of the tornado. Cyclonic vortices of 100–200 m width were found along a bow-shaped line of enhanced radar reflectivity, at what appears to have been the leading edge of a rear-flank gust front. At the time of tornadogenesis, one of these vortices was located just ahead of the nose of the bow-shaped radar echo and a jet, which were embedded within a larger-scale cyclone. At other times, small-scale cyclonic vortices coexisted with the tornado along an arc-shaped line extending to its north and northeast but did not appear to interact with the tornado. The ...
Controllability and stabilizability of coupled strings with control applied at the coupled points

Controllability and stabilizability of a system of coupled strings with control applied at the coupled points is studied. By investigating the properties of certain exponential series, it is shown that the system is approximate controllable if and only if related systems of uncoupled strings do not share a common eigenvalue. A sufficient condition for exact controllability is also obtained in terms of the Riesz basis properties of those exponential series.
Multiple hairs (Flemming-Giovannini; report of two cases of pili multigemini and discussion of some other anomalies of the pilary complex.

Of all the adnexa of the skin, the hair has the most elaborately balanced structure. Only minor deviations from the norm are compatible with the formation of a viable hair. Two of the basic rules of hair morphogenesis are these: 1. One papilla forms only one hair at one time; 2. Each hair is a unit, a single thread made up of concentric layers, and does not branch or become subdivided. These rules hold true not only for human hair. From the finest hair of the chinchilla fur to the coarsest vibrissa of the tiger, hair formation follows the same rigid rules.
Total Internal Reflection Microscopy: Distortion Caused by Additive Noise

Total internal reflection microscopy (TIRM) is an optical technique for monitoring Brownian fluctuations in the separation between a single microscopic sphere and a flat plate in aqueous media. The sphere is levitated above the plate by colloidal forces such as double-layer or steric repulsion. Changes in elevation as small as 1 nm can be detected by measuring the light scattered by a single sphere when illuminated by an evanescent wave. From the Boltzmann distribution of elevations sampled by the sphere over a long time, the potential energy (PE) profile can be determined with a resolution of about 0.1kT. By corrupting clean data (having a mean scattering intensity of Īs and a standard deviation of σs) obtained by Brownian dynamics simulations with various levels of additive background noise (having a mean background intensity of Īb and a standard deviation of σb), we show how the PE profiles obtained from TIRM are distorted. Increasing Īb narrows the profile and shifts it toward smaller elevations; conv...
Industrial hygiene chemistry: keeping pace with rapid change in the workplace.

Sanitation and Radiation Laboratory, California Department of Health Services, 2151 Berkeley Way, Berkeley, California 94704, U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Cincinnati, Ohio 45226, Ashland Chemical Inc., 5200 Blazer Parkway, Dublin, Ohio 43017, and Monsanto Company, 800 North Lindbergh Boulevard, St. Louis, Missouri 63167
Mastocytosis: the new differential diagnosis of CD30-positive neoplasms.

Mastocytosis is a very rare, clonal disease characterized by the accumulation of mast cells in one or more organ systems. It is characterized by the presence of multifocal compact clusters or cohes...
CHILD syndrome: analysis of abnormal keratinization and ultrastructure.

: A new patient with CHILD syndrome (congenital hemidysplasia, ichthyosiform erythroderma, and limb defects), the thirtieth in the literature, was observed for over three years. Initially, the right-sided lesion spared the breast area. At 10 months of age the trunk lesion extended to cover the entire area of the right chest At age 20 months the patient developed linear, bandlike, keratotic, brown-black lesions on her teft thigh that subsided within six weeks, leaving a slight hyperpigmentation. This patient was studied by routine histologic methods as well as with markers of keratinlzation and electron microscopy. In hematoxylin and eosinstained sections, parakeratosis and orthokeratosis atternated. In some parakeratotlc areas, targe granular cells, and in others, ghost granular cells, were present. The latter showed basophilic cytoplasm, and palestaining or vacuolated nucleus and were seen either above the normal granular layer or without it. Although regional variations existed, basat cell-type keratins as recognized by AE1 continued to be expressed in suprabasal layers. Filaggrin- and Involucrin-positive layers were expanded, particularly the latter, down to the lower prickle cell layer. Ultrastructurally, numerous lamellar or membranous structures were found in upper layers of the epidermis, both intracellulary and intercellularly. Normal cementsomes coexisted with these abnormal lamellar structures, and it was thought that the latter represent modified cementsomes because the discharge of those from the cell periphery was Often detected.
Intestinal Glutamine Synthetase (Gs) and Dna Synthesis are Concurrently Upregulated By Dexamethasone (Dex) in Vitro † 571

Intestinal Glutamine Synthetase (Gs) and Dna Synthesis are Concurrently Upregulated By Dexamethasone (Dex) in Vitro † 571
Abnormal cardiac rhythms caused by acetylcholine.

The effect of topical administration of acetylcholine on the auricular and ventricular surface of the dog's heart was studied. The experiments show the appearance of variform arrhythmias, particularly auricular fibrillation. The tendency for the development of these arrhythmias is diminished, but not abolished by atropinization. The experiments confirm previous results of the authors according to which auricular flutter is due to a rapid stimulus formation in a center. They help explain the occasional appearance of extrasystoles and paroxysmal tachycardias during vagus stimulation in experimental and clinical observations.
Vehicle classification by pattern-matching gauge sensors

This paper describes a method of using matched-pattern gage sensors that are embedded into highway pavements to classify vehicles, i.e. cars vs. trucks. The classification of vehicle type is an important technology for a variety of highway operations, e.g. traffic control, maintenance planning, weigh-in-motion, and the assignment of tolls. Vehicle classification schemes that are based on strip-crossing methods are not very robust due to the large variability of strip-crossing sequences. Visual methods still rely primarily on human identification. The method described here involves placing long gage length sensors in highway pavements. The spatial pattern of the sensor is configured so that it will match the wheel pattern of the type of vehicle that is being identified. Theoretical modeling shows that the signal received from the sensor is a cross-correlation function relating the wheel and sensor patterns in space and time. The sensor can be any one of a variety that transduce by integrating pressure along a length. The technique is demonstrated in the laboratory with PVDF and fiber optic sensors. Experimental results and computer simulations are presented as well as a discussion of the realistic possibility of using such a vehicle identification scheme under field conditions.
Interaction of globular actin with myosin subfragments.

Abstract We have attached a spin label or a fluorescent dye to actin to probe the interaction of G-actin with myosin subfragments. The spin label spectra, which are sensitive to the polymerization of the actin, showed that when heavy meromyosin was added to G-actin the actin was polymerized. When actin was in excess, the spin label spectra indicated that 3.8 ± 0.6 actin monomers were polymerized per heavy meromyosin molecule. Addition of myosin subfragment-1 on the other hand caused a negligible amount of actin polymerization as measured by the spectra of the spin label attached to the actin. The polarization of the fluorescence of the dye bound to actin increased upon addition of heavy meromyosin to the G-actin. In good agreement with the spin label results, the fluorescence data indicated that, when actin was in excess, 4.2 actin monomers were incorporated into a polymer per heavy meromyosin molecule added. One heavy meromyosin per two actin monomers was necessary and sufficient to “polymerize” all of the actin. When heavy meromyosin was added to succinylated actin, which was incapable of polymerization, the same changes in the fluorescent polarization were observed as with unsuccinylated actin. Addition of subfragment-1 to fluorescent-labeled actin indicated that subfragment-1 formed a 1:1 molar complex with the actin monomers. These data are interpreted in terms of a model in which the heavy meromyosin and actin form a copolymer which involves cooperative interactions between the two heads of heavy meromyosin.
Starting out: The early phases of four creative careers—darwin, van Gogh, Freud, and Shaw

This paper introduces the four that follow it. The others deal with the phase of the creative career we call “starting out.” Of the four individuals discussed in those papers, Darwin moved rather smoothly from an early phase of field work in natural history to a later phase of theoretical biology. His work in natural history became incorporated within the theoretical enterprise, the whole move being accomplished by about the age of 30. van Gogh had a protracted early phase as a mediocre art dealer and then as a failed Christian minister to the poor, rejected and scorned by his co-religionists. At about the age of 30 he made a clear commitment to a career in art and began a long period of training, seeking help from other artists but mainly directing his own development. As with Darwin there was a certain degree of overlap of earlier and later phases, in the sense that his art displayed religious overtones for some time. Freud had brilliant early careers—as a neurologist and as a medical practitioner. He did not move decisively toward psychoanalysis until his early forties. Shaw, too, had brilliant early careers—as a radical orator, as a journalist, and as a music critic. His career as a dramatist did not begin in earnest until his forties. Three of the four produced “initial sketches” that were significant in prefiguring their later careers: Darwin'sJournal of the voyage of theBeagle, Freud'sThe Project, and Shaw's letter,Dear Dorothea. Other topics are taken up as appropriate in one or other of the four cases: the network of enterprise, the ensemble of metaphors, the belief system, and the social web. Taken together with a discussion of the uniqueness of each creative person, they give a sense of the evolving systems approach to creative work.
Temperature dependent near-UV molar absorptivities of aliphatic aldehydes and ketones in aqueous solution

Abstract Temperature dependent molar absorptivities are reported for acetone, 2-butanone, 2-pentanone, 3-pentanone, acetaldehyde, propionaldehyde, and n -butyraldehyde in aqueous solution. Molar absorptivities are given at eight temperatures in the range 6.5–69.5°C for wavelengths greater than 200 nm, a spectral resolution of 2.0 nm, and a spacing of 2.5 nm. For both ketones and aldehydes a shift to shorter wavelengths of approximately 10 nm is observed in the aqueous phase absorption spectrum relative to that found in the gas phase. For the ketones, there is an increase in the total intensity of the spectrum of approximately 5% over the range of temperatures studied. For the aldehydes a much larger change in the intensity of the absorption spectrum is observed, due to the temperature dependence of the hydration reaction RCHO + H 2 O ⇄ RCH(OH) 2 ; K hyd = [RCH(OH) 2 /[RCHO]. The change in the spectral intensity with temperature is used to determine thermodynamic parameters for the hydration reaction, giving the following results (at 25°C): acetaldehyde, K hyd = 1.13 ± 0.06, Δ H = −19.7±0.6kJ/mol, Δ S = −65.0±2.5J/mol-K; propionaldehyde, K hyd =1.02±0.06, ΔH=-20.8±0.8kJ/mol, Δ S =-69.6±3.1J/mol-K; n -butyraldehyde, K hyd =0.50±0.05, ΔH=-27.0±2.2kJ/mol, Δ S = −96.5± 8.2 J/mol-K. The implications of these results for aqueous phase atmospheric chemistry are discussed.
Substitutes for leadership, or not

Abstract In this exchange of theoretical letters, Dionne and Yammarino and Howell and Villa revisit the relevance and usefulness of the substitutes for leadership construct. Dionne and Yammarino focus on the importance of leadership and problems with the substitutes concept, operationalization, and tests. Howell endorses and clarifies the notion of substitutes for leadership as currently conceptualized and tested. As such, Dionne and Yammarino and Howell and Villa agree that the substitutes for leadership construct requires further development.
Murex from the Red Sea

IN the early months of 1951, Sir John Graham Kerr collected some three hundred Murex tribulus shells on the western shore of the Great Bitter Lake south of the village of Fayid. It will be remembered that the entire animal population has been introduced subsequent to the cutting of the Suez Canal in 1869, which opened the way for immigrant organisms from the Red Sea. Now, granted the inherent tendency of living creatures to vary when relieved of the shackles of environment, Sir John argued that, in their new environment of the Bitter Lakes, these Murex specimens had had an opportunity of responding to this tendency, and hence the remarkable variety of sculpture in the random collection. Moreover, this variation exhibited in spines and tubercles is not a matter of mere superficial markings, but rather of deep-seated causes such as the localized growth of the mantle edge or the depth in the mud occupied by the individual animal. The shells were in perfect condition, there being practically no tides in the Bitter Lakes and no violent wave action, and the bottom is soft mud.
Syntheses and evaluation of biodegradable multifunctional polymer networks

Abstract The biodegradable, injectable and in situ crosslinkable polymer networks based upon di(propylene fumarate)–dimethacrylate (DPFDMA) and polycaprolactone trimethacrylate (PCLTMA), were prepared and characterized. The polymer networks were initiated by photopolymerization. The initial compressive (CS) and diametral tensile strengths (DTS) of the networks materials were determined and used to evaluate the effects of PCLTMA/DPFDMA ratios on the degradation behavior. The networks exhibited initial DTS values ranging from 2.5 to 9.3 MPa and CS values ranging from 1.8 to 146.0 MPa. The increase of PCLTMA in the formulation led to an increase in viscosity and DTS. The degree of conversions and polymerization shrinkage of the resins ranged from 60% to 72% and 5.1% to 6.4%, respectively. After 6 month, PCL300TMA/DPFDMA resins at a ratio of 100/0, 75/25 and 25/75 lost 70%, 87% and 46% of their initial CS, respectively, while PCL900TMA/DPFDMA and PCL300TMA/PCL900TMA resins at 75/25 lost 100% and 83% of their initial CS, respectively.
The interendocrine regulation of larval-pupal development in the tobacco hornworm, Manduca sexta: A model

Abstract The postembryonic development of insects is directed by precise fluctuations in the titres of two families of hormones, the juvenile hormones and ecdysteroids. These titre changes are dictated by the dynamic interaction of these two endocrine systems in a complex interregulatory scheme. The nature of this interendocrine regulation during larval-pupal development is being intensively investigated in the tobacco hornworm, Manduca sexta . Interendocrine regulation in this species appears to be quite complex and involves various physiological processes, among them the competency of endocrine glands to produce the hormones, the involvement of multiple regulators at different levels, and temporally precise changes in hormone titres. The coordination of the entire process appears to occur within the brain, and the means by which this occurs seems to change as development progresses. Based upon current knowledge of the interendocrine regulation of larval-pupal development in Manduca , a model is presented that explains the nature and extent of this control in directing this insect's development. It is hoped that this model will serve as a foundation for future experiments designed to refine our understanding of the interendocrine regulation of insect postembryonic development.
Role of adrenergic innervation in experimental renal hypertension

Abstract Renal hypertension was induced by ligation of the aorta between renal arteries in rats sympathectomized with 6-hydroxydopamine. In the early phase, equally severe hypertension developed in the denervated group as compared to innervated controls. Later, blood pressure was lower in the denervated rats. Initially, increases in plasma renin were seen in both groups; the levels, however, were markedly lower in the denervated rats. Later, the renin levels were similar and not different from baseline. It is concluded that adrenergic neural activity is not essential in the development of renal hypertension; the maintenance of the chronic state, however, depends in part on adrenergic innervation.
EM analysis of Drosophila chorion genes: amplification, transcription termination and RNA splicing.

Abstract We have used the electron microscope to examine ultrastructurally several events occuring during the biogenesis of two very abundant chorion (eggshell) mRNA molecules in the follicle cells of Drosophila melanogaster—namely, selective gene amplification, transcription initiation and termination, and RNA rocessing. We find that the highly transcribed s36 and s38 genes are positioned in the central region of large, multi-forked amplified DNA structures. Transcript morphology is consistent with the known presence of a small intron at the 5' end of each gene. mature transcripts are associated with spliceosomes, demonstrating that splice site selection occurs co-transcriptionally but that splicing is completed after transcript release from the template. We have also mapped the termination sites for the genes. The two genes exhibit efficient termination very near their poly(A) sites—within a 210 bp region for s36 and a 360 bp region for s38.
Bacterial social engagements

Quorum sensing is a process that enables bacteria to communicate using secreted signaling molecules called autoinducers. This process enables a population of bacteria to regulate gene expression collectively and, therefore, control behavior on a community-wide scale. Quorum sensing is widespread in the bacterial world and, generally, processes controlled by quorum sensing are unproductive when undertaken by an individual bacterium but become effective when undertaken by the group. Cell–cell communication can occur within and between bacterial species, and between bacteria and their eukaryotic hosts, which suggests that the chemical lexicon is complex. Prokaryotic and eukaryotic mechanisms for enhancing and inhibiting quorum sensing have been identified, which suggests that manipulation of quorum-sensing-controlled processes could be common in bacterial–bacterial and bacterial–eukaryotic associations.
Increased transmigration of G–CSF‐mobilized peripheral blood CD34+ cells after overnight storage at 37°C

BACKGROUND G-CSF-mobilized PBPCs are utilized in allogeneic and autologous PBPC transplants. Homing, adhesion, and transmigration of hematopoietic CD34+ cells are required for successful engraftment. Hematopoietic CD34+ cells undergo directional migration toward the CXCR4 receptor ligand stromal-derived factor-1 (SDF-1). Limited data are available on the effects of liquid storage and cryopreservation on PBPC CD34+ cells. STUDY DESIGN AND METHODS Magnetic-assisted cell sorting (MACS)-selected CD34+ cells were assayed for retention of in vitro transmigration and phenotypic changes of unit-matched liquid-stored and cryopreserved PBPC samples from healthy donors. Studies evaluated whether transmigration of CD34+ cells in Iscove's modified Dulbecco's medium plus 1 percent HSA alone or in medium supplemented with SCF or allogeneic plasma was affected by overnight incubation at 37 degrees C, relative to nonincubated conditions. RESULTS Transmigration was maintained during liquid storage at 1 to 6 degrees C during a 2-day period and in unit-matched cryopreserved-thawed samples that had been initially liquid stored. Overnight incubation at 37 degrees C of MACS-selected unit-matched liquid-stored or cryopreserved-thawed CD34+ cells resulted in substantially increased transmigration, in particular with noncoated filters chemoattracted with the chemokine SDF-1. CONCLUSION CD34+ cell transmigration was comparable between liquid-stored and cryopreserved samples, and both demonstrated similar increases after overnight incubation at 37 degrees C.
Spindle Fusion Requires Dynein-Mediated Sliding of Oppositely Oriented Microtubules

Summary Background Bipolar spindle assembly is critical for achieving accurate segregation of chromosomes. In the absence of centrosomes, meiotic spindles achieve bipolarity by a combination of chromosome-initiated microtubule nucleation and stabilization and motor-driven organization of microtubules. Once assembled, the spindle structure is maintained on a relatively long time scale despite the high turnover of the microtubules that comprise it. To study the underlying mechanisms responsible for spindle assembly and steady-state maintenance, we used microneedle manipulation of preassembled spindles in Xenopus egg extracts. Results When two meiotic spindles were brought close enough together, they interacted, creating an interconnected microtubule structure with supernumerary poles. Without exception, the perturbed system eventually re-established bipolarity, forming a single spindle of normal shape and size. Bipolar spindle fusion was blocked when cytoplasmic dynein function was perturbed, suggesting a critical role for the motor in this process. The fusion of Eg5-inhibited monopoles also required dynein function but only occurred if the initial interpolar separation was less than twice the microtubule radius of a typical monopole. Conclusions Our experiments uniquely illustrate the architectural plasticity of the spindle and reveal a robust ability of the system to attain a bipolar morphology. We hypothesize that a major mechanism driving spindle fusion is dynein-mediated sliding of oppositely oriented microtubules, a novel function for the motor, and posit that this same mechanism might also be involved in normal spindle assembly and homeostasis.
How Often do BSN Students Participate in Pediatric Critical Events during Simulation and Hospital Rotations

Abstract Background With nursing students' limited access to pediatric patients. coupled with an expectation that the novice nurse be proficient in managing deteriorating patient conditions, nurse educators may choose to supplement students' clinical rotation with simulation. The question remains, What experiences are "available" in clinical, and which ones are rarely seen and therefore should be simulated? Method A list of 18 pediatric critical events was rated by pediatric nurse experts as not important, somewhat important, very important, or vitally important for the novice nurse to recognize, report, and intervene in. Students were asked to report on the number of times they intervened to correct these critical events in both the clinical arena and the simulation laboratory. Students were also asked to rate their confidence in performing these interventions after their clinical and their simulation experiences. Results The survey results indicate that students had significantly more experiences with most of the pediatric critical events in the simulation lab than in the pediatric inpatient unit. For each of the pediatric critical events, the mean comfort level was higher after simulation than after clinical. Conclusions A mixed educational model is effective in introducing students to the competencies expected of the novice nurse.
Synthesis, self-assembly, and magnetic properties of [FePt]/sub 1-x/Au/sub x/ nanoparticles

[FePt]/sub 1-x/Au/sub x/ nanoparticles were prepared by the simultaneous polyol reduction of platinum acetylacetonate and gold acetate and the thermal decomposition of iron pentacarbonyl, giving 3.5-nm-diameter FePt particles with gold atoms substituted in the lattices. The addition of gold promoted the face-centered cubic to tetragonal phase transition, thereby reducing the temperature required for this transition by more than 150/spl deg/C compared with FePt nanoparticles with no additives. This effect is even more significant than adding silver to FePt nanoparticles. For a given annealing temperature, the coercivity increases with the content of gold up to 24%, above which the coercivity starts to decrease. The mechanism for the chemical ordering acceleration may relate to the defect and strains introduced by gold atoms. Upon annealing, gold atoms leave the FePt lattice, leaving lattice vacancies that increase the mobility of the FePt atoms to rearrangement. Dynamic coercivity measurements yield thermal stability factors that are slightly higher than would be expected for noninteracting particles.
Three-stage assembly of the cysteine synthase complex from Escherichia coli.

Control of sulfur metabolism in plants and bacteria is linked, in significant measure, to the behavior of the cysteine synthase complex (CSC). The complex is comprised of the two enzymes that catalyze the final steps in cysteine biosynthesis: serine O-acetyltransferase (SAT, EC 2.3.1.30), which produces O-acetyl-l-serine, and O-acetyl-l-serine sulfhydrylase (OASS, EC 2.5.1.47), which converts it to cysteine. SAT (a dimer of homotrimers) binds a maximum of two molecules of OASS (a dimer) in an interaction believed to involve docking of the C terminus from a protomer in an SAT trimer into an OASS active site. This interaction inactivates OASS catalysis and prevents further binding to the trimer; thus, the system exhibits a contact-induced inactivation of half of each biomolecule. To better understand the dynamics and energetics that underlie formation of the CSC, the interactions of OASS and SAT from Escherichia coli were studied at equilibrium and in the pre-steady state. Using an experimental strategy that initiates dissociation of the CSC at different points in the CSC-forming reaction, three stable forms of the complex were identified. Comparison of the binding behaviors of SAT and its C-terminal peptide supports a mechanism in which SAT interacts with OASS in a non-allosteric interaction involving its C terminus. This early docking event appears to fasten the proteins in close proximity and thus prepares the system to engage in a series of subsequent, energetically favorable isomerizations that inactivate OASS and produce the fully isomerized CSC.
Further Studies of the Effect of Dilution Rate on the Fertility of Bull Semen Used for Artificial Insemination

Summary In a study involving 3,296 inseminations, dilution rates of 1 part of semen to 8, 12, 16, 24 and 50 parts of yolk-citrate diluter were compared. The experiment was designed so as to eliminate all arbitrary selection of the semen to be used at any dilution rate. On the average, the following number of spermatozoa were contained in the 1ml. of diluted semen used for each insemination: 150, 104, 80, 54 and 26 millions. No statistically significant differences were found in fertility of the semen for the 5 dilution rates compared. The semen diluted at the highest rate was not used as efficiently as the semen diluted at the lower rates, but, on the average, seemed to maintain its fertility as well for 4 days after collection.
Adsorption of seminal plasma proteins by boar spermatozoa.

Abstract Seminal plasma protein adsorption by boar spermatozoa was examined using ejaculated sperm from vesiculectomized boars and seminal plasma from vasectomized boars. Sperm adsorbed 14 pg protein/sperm in 10 min. When seminal plasma proteins were radiolabeled, most of the adsorbed radiolabel was present in low Mr proteins, particularly a 12700 Mr protein. A 349300 Mr seminal plasma protein was also readily adsorbed. Three radiolabeled seminal plasma proteins (307600, 165400 and 7400 Mr) were not detected on the sperm; either they are not adsorbed by the sperm or the sperm were previously exposed to these proteins in other accessory sex gland fluids and had already adsorbed them. A 29100 Mr sperm protein was also radiolabeled (4.9% of the adsorbed radiolabel), although there was no corresponding seminal plasma protein. Large quantities of seminal plasma protein (particularly low Mr proteins) are adsorbed by sperm not previously exposed to seminal vesicle secretion. The functions of these proteins are yet to be determined.
Cultural Considerations for Residential Treatment of Children and/or Adolescents.

ABSTRACT The issue of culture has been scantly addressed in the field of youth residential treatment. However, little research has explored salient aspects of youth culture in residential treatment settings. In addition to the usual definitions of culture (i.e., race, ethnicity, rural/urban, low/high income), youth often note other unique cultural variations in their existence: substances of choice and availability, language, social interactions, family interactions, preferred music, styles of interactions, and resistance strategies. Issues of “peer contagion” and counter perspectives related to the concept of Positive Peer Culture are discussed. Implications of culture in youth residential treatment are explored and recommendations for culturally grounding programs are made. The author places special emphasis on the importance of consulting with youth throughout program formation, implementation and evaluation.
Approaches to inverse-probability-of-treatment--weighted estimation with concurrent treatments.

Abstract Objectives In a setting with two concurrent treatments, inverse-probability-of-treatment weights can be used to estimate the joint treatment effects or the marginal effect of one treatment while taking the other to be a confounder. We explore these two approaches in a study of intravenous iron use in hemodialysis patients treated concurrently with epoetin alfa (EPO). Study Design and Setting We linked US Renal Data System data with electronic health records (2004–2008) from a large dialysis provider. Using a retrospective cohort design with 776,203 records from 117,050 regular hemodialysis patients, we examined a composite outcome: mortality, myocardial infarction, or stroke. Results With EPO as a joint treatment, inverse-probability-of-treatment weights were unstable, confidence intervals for treatment effects were wide, covariate balance was unsatisfactory, and the treatment and outcome models were sensitive to omission of the baseline EPO covariate. By handling EPO exposure as a confounder instead of a joint treatment, we derived stable weights and balanced treatment groups on measured covariates. Conclusions In settings with concurrent treatments, if only one treatment is of interest, then including the other in the treatment model as a confounder may result in more stable treatment effect estimates. Otherwise, extreme weights may necessitate additional analysis steps.
COST COMPARISON OF ORCHIECTOMY AND LEUPROLIDE IN METASTATIC PROSTATE CANCER

AbstractPurpose: We objectively compare the costs associated with the medical and surgical treatment of metastatic prostate cancer.Materials and Methods: We analyzed and compared itemized billing statements for 28 men with metastatic adenocarcinoma of the prostate. Half of the men were treated medically with the luteinizing hormone-releasing hormone analogue leuprolide, while the other half underwent bilateral therapeutic orchiectomy. In addition, differences in hospital cost to treat these men were calculated.Results: During a mean followup of 24 months leuprolide treated patients were charged $500.00 per month of treatment compared to average monthly expenditure of $226.00 for orchiectomy patients during a 23-month interval. By 9 months charges incurred by both groups were equal and by 20 months medically treated patients accumulated urological charges twice that of the surgically treated patients. The true hospital cost to treat these patients followed the same trend, that is the medically treated grou...
Characterization and purification of iron porphyrins by high-performance liquid chromatography and column chromatography.

In this paper we report the HPLC characteristics of a variety of ferric porphyrins, both natural (derived from protoporphyrin IX) and synthetic (derived from tetraphenylporphyrin)
Role for G-Quadruplex RNA Binding by Epstein-Barr Virus Nuclear Antigen 1 in DNA Replication and Metaphase Chromosome Attachment

Latent infection by Epstein-Barr virus (EBV) requires both replication and maintenance of the viral genome. EBV nuclear antigen 1 (EBNA1) is a virus-encoded protein that is critical for the replication and maintenance of the genome during latency in proliferating cells. We have previously demonstrated that EBNA1 recruits the cellular origin recognition complex (ORC) through an RNA-dependent interaction with EBNA1 linking region 1 (LR1) and LR2. We now show that LR1 and LR2 bind to G-rich RNA that is predicted to form G-quadruplex structures. Several chemically distinct G-quadruplex-interacting drugs disrupted the interaction between EBNA1 and ORC. The G-quadruplex-interacting compound BRACO-19 inhibited EBNA1-dependent stimulation of viral DNA replication and preferentially blocked proliferation of EBV-positive cells relative to EBV-negative cell lines. BRACO-19 treatment also disrupted the ability of EBNA1 to tether to metaphase chromosomes, suggesting that maintenance function is also mediated through G-quadruplex recognition. These findings suggest that the EBNA1 replication and maintenance function uses a common G-quadruplex binding capacity of LR1 and LR2, which may be targetable by small-molecule inhibitors.
Tinea Capitis Mimicking Dissecting Cellulitis

Tinea capitis is a common disease of childhood that typically follows one of several clinical patterns. Our patient and several previously reported cases demonstrate the existence of a dissecting cellulitis-like presentation of tinea capitis. This variant should be recognized to prevent misdiagnosis of dissecting cellulitis and allow proper treatment to prevent scarring alopecia.
Limits and responsibilities of physicians addressing spiritual suffering in terminally ill patients.

Abstract Context Many patients experience spiritual suffering that complicates their physical suffering at the end of life. It remains unclear what physicians' perceived responsibilities are for responding to patients' spiritual suffering. Objectives To investigate U.S. physician opinions about the impact patients' unresolved spiritual struggles have on their physical pain, physicians' responsibilities for treating patients' spiritual suffering compared with patients' physical pain, and the number of patients in the past 12 months whose suffering the physician was unable to relieve to an acceptable point. Methods The study was based on a mailed survey to 2016 practicing U.S. physicians from clinical specialties that care for significant numbers of dying patients. Results Of 1878 eligible physicians, 1156 (62%) responded. Most physicians agreed that patients with unresolved spiritual struggles tend to have worse physical pain (81%) and that physicians should seek to relieve patients' spiritual suffering just as much as patients' physical pain (88%). Compared with physicians who strongly disagreed that physicians should seek to relieve patients' spiritual suffering just as much as patients' physical pain, those who strongly agreed were less likely to report being unable to relieve patients' suffering to a point the physician found acceptable (27% vs. 54% reported three or more such patients in the previous 12 months, adjusted odds ratio [95% CI] = 0.3 [0.1, 0.8]). Conclusion Most physicians believe that spiritual suffering tends to intensify physical pain and that physicians should seek to relieve such suffering. Physicians who believe they should address spiritual suffering just as much as physical pain report more success in relieving patient's suffering.