bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heat Shock RNA Levels in Brain and Other Tissues After Hyperthermia and Transient Ischemia
Authors: Nowak Thaddeus S. , Bond Ursula , Schlesinger Milton J. 
Published: October 2006

Abstract:A number of studies have demonstrated increased synthesis of heat shock proteins in brain following hyperthermia or transient ischemia. In the present experiments we have characterized the time course of heat shock RNA induction in gerbil brain after ischemia, and in several mouse tissues after hyperthermia, using probes for RNAs of the 70‐kilodalton heat shock protein (hsp70) family, as well as ubiquitin. A synthetic oligonucleotide selective for inducible hsp70 sequences proved to be the most sensitive indicator of ± the stress response whereas a related rat cDNA detected both induced RNAs and constitutively expressed sequences that were not strongly inducible in brain. Considerable polymorphism of ubiquitin sequences was evident in the outbred mouse and gerbil strains used in these studies when probed with a chicken ubiquitin cDNA. Brief hyperthermic exposure resulted in striking induction of hsp70 and several‐fold increases in ubiquitin RNAs in mouse liver and kidney peaking 3 h after return to room temperature. The oligonucleotide selective for hsp70 showed equivalent induction in brain that was more rapid and transient than observed in liver, whereas minimal induction was seen with the ubiquitin and hsp70‐related cDNA probes. Transient ischemia resulted in 5‐ to 10‐fold increases in hsp70 sequences in gerbil brain which peaked at 6 h recirculation and remained above control levels at 24 h, whereas a modest 70% increase in ubiquitin sequences was noted at 6 h. These results demonstrate significant temporal and quantitative differences in heat shock RNA expression between brain and other tissues following hyperthermia in vivo, and indicate that hsp70 provides a more sensitive index of the stress response in brain than does ubiquitin after both hyperthermia and ischemia. These studies emphasize the importance of using probes selective for stress‐inducible hsp70 sequences in evaluation of the heat shock response, particularly in tissues such as brain in which there is significant constitutive expression of hsp70‐related proteins.
Increased Intracellular Calcium Stimulates 3H‐Inositol Polyphosphate Accumulation in Rat Cerebral Cortical Slices
Authors: Baird John G. , Nahorski Stefan R. 
Published: October 2006

Abstract:Agents that increase the intracellular Ca2+ concentration have been examined for their ability to stimulate 3H‐inositol polyphosphate accumulation in rat cerebral cortex slices. Elevated extracellular K+ levels, the alkaloid sodium channel activator veratrine, the calcium ionophore ionomycin, and the marine toxin maitotoxin were all able to stimulate phosphoinositide metabolism. Certain features appear common to the agents studied. Thus, although [3H]inositol monophosphate, [3H]inositol bisphosphate ([3H]InsP2), and [3H]inositol trisphosphate were all stimulated, a proportionally greater effect was observed on [3H]InsP2 in comparison to stimulation by the muscarinic receptor agonist carbachol. However, only an elevated K+ level stimulated [3H]inositol tetrakisphosphate ([3H]InsP4) accumulation alone or produced marked synergy with carbachol on the formation of this polyphosphate. The results suggest that agents that elevate the cytoplasmic Ca2+ concentration in cerebral cells can increase the hydrolysis of membrane polyphosphoinositides. The pattern of the response differs from that produced by muscarinic receptor agonists and indicate that Ca2+‐dependent hydrolysis may involve different pools of lipids, phosphoinositidase C enzymes, or both. However, clear differences in the ability of these agents to stimulate InsP4, alone or in the presence of muscarinic agonist, suggest that factors other than a simple elevated intracellular Ca2+ concentration are implicated.
Enhancement of In Vivo Tyrosine Hydroxylation in the Rat Adrenal Gland Under Hypoxic Conditions
Authors: Hayashi Yasunori , Miwa Soichi , Lee Ken , Koshimura Kunio , Hamahata Keigo , Hasegawa Hiroshi , Fujiwara Motohatsu , Watanabe Yasuyoshi 
Published: October 2006

Abstract:We examined the effects of hypoxia (8% O2) on in vivo tyrosine hydroxylation, a rate‐limiting step for catecholamine synthesis, in the rat adrenal gland. The hydroxylation rate was determined by measuring the rate of accumulation of 3,4‐dihydroxyphenylalanine (DOPA) after decarboxylase inhibition. One hour after hypoxic exposure. DOPA accumulation decreased to 60% of control values, but within 2 h it doubled. At 2 h, the apparent Km values for tyrosine and for biopterin cofactor of tyrosine hydroxylase (TH) in the soluble fraction were unchanged, whereas the Vmax value increased by 30%. The content of total or reduced biopterin was unchanged, but the content of tyrosine increased by 80%. Tyrosine administration had little effect on DOPA accumulation under room air conditions but enhanced DOPA accumulation under hypoxia. After denervation of the adrenal gland, the hypoxia‐induced increase in DOPA accumulation and in the Vmax value was abolished, whereas the hypoxia‐induced increase in tyrosine content was persistent. These results suggest that in vivo tyrosine hydroxylation is enhanced under hypoxia, although availability of oxygen is reduced. The enhancement is the result of both an increase in tyrosine content coupled with increased sensitivity of TH to changes in tyrosine tissue content and of an increase in dependence of TH on tyrosine levels. The increase in the sensitivity of TH and in the Vmax value is neurally induced, whereas the increase in tyrosine content is regulated by a different mechanism.
Arachidonic Acid Liberated by Diacylglycerol Lipase Is Essential for the Release Mechanism in Chromaffin Cells from Bovine Adrenal Medulla
Authors: Rindlisbacher B. , Sidler M. A. , Galatioto L. E. , Zahler P. 
Published: October 2006

Abstract:Chromaffin cells from bovine adrenal medulla secrete catecholamines on stimulation with acetylcholine. In addition to the activation of the phosphatidylinositol cycle, arachidonic acid is generated, which was thought to be the result of phospholipase A2 activation. We have demonstrated in isolated plasma membranes of these cells that arachidonic acid is generated by a two‐step reaction of diacylglycerol and monoacylglycerol lipase splitting diacylglycerol, which originates from the action of phospholipase C on phosphatidylinositols. No phospholipase A2 activity could be detected in plasma membranes so far. External addition of arachidonic acid increases the release in the absence and in the presence of agonist. Inhibition of the diacylglycerol lipase by RHC 80267 suppresses the catecholamine release, which is restored on addition of arachidonic acid. This effect, however, is reversed by lipoxygenase inhibitors, indicating that it is not arachidonic acid itself, but one of its lipoxygenase products, that is essential for inducing exocytosis.
Lupus erythematosus: clinical and histopathological study of oral manifestations and immunohistochemical profile of epithelial maturation
Authors: Lourenço Silvia Vanessa , Nacagami Sotto Mirian , Constantino Vilela Maria Apparecida , Rodrigues Gonçalves de Carvalho Fabio , Rivitti Evandro A. , Menta Simonsen Nico Marcello 
Published: October 2006

Background: Lupus erythematosus (LE) is an autoimmune disease of unknown cause. Prevalence of oral involvement in patients with LE is uncertain but may vary from 9 to 45% in patients with systemic disease and from 3 to 20% in patients with chronic cutaneous involvement.Methods: Incidence of oral lesions of LE and their clinical aspects were investigated. Their histopathologic features were analyzed, and the status of epithelial maturation was assessed through the expression patterns of cytokeratins.Results: Twenty‐six patients (from 188 examined) presented oral lesions of LE. Most of them were females (19) with systemic disease (11). Clinical aspects of these lesions varied, and lips and buccal mucosa were most affected. Histologically, lesions revealed lichenoid mucositis with perivascular infiltrate and thickening of basement. Cytokeratins profile showed hyperproliferative epithelium, with expression of CK5/6, and CK14 on all epithelial layers, CK16 on all suprabasal layers and CK10 on prickle cell layers only.Conclusions: Oral lesions of LE show a variety of aspects, and their microscopic features are of a lichenoid mucositis with deep inflammatory infiltrate. Cytokeratins expression patterns are of hyperproliferative epithelium, and this phenomenon must be analyzed in relation to the inflammatory cytokines for a better understanding of the mechanisms of the disease.
Prolonging Effective Penicillin Action
Authors: Trumper Max , Hutter A. M. 
Published: October 2006

(1) Single injections of penicillin in saline administered intramuscularly with ice applications at the site of the injection produced and maintained bacteriostatic levels for six to twelve hours in nine out of ten patients, nine of whom were diagnosed as having gonorrhea and one urethritis with extracellular diplococci.
(2) There was one failure, Subject No. 10, who received only 30,000 units.
(3) Eight of the patients with gonorrhea and the one patient with urethritis were cured (bacteriologically and clinically) by this single intramuscular injection of penicillin.
Patination of Cultural Flints
Authors: Hurst Vernon J. , Kelly A. R. 
Published: October 2006

All flints containing unstable impurities are susceptible to patination. The rate of patination varies with many factors: (i) the texture and microstructure of the flint; (ii) its permeability; (iii) the kind, proportion, and distribution of impurities; and (iv) environmental factors, such as temperature and soil chemistry. The thickness of the patina varies also with time.
Two contrasting types of patina can develop: a chalky white patina and a ferruginous brown patina. Both types are observable primarily as a color change, and study of these types is facilitated by a clear understanding of the causes of color in flint.
The color of most flints is the result of repeated refraction and reflection of light at numerous intergranular surfaces, whereby part of the light is internally absorbed and part is reflected back to the observer. The ratio of reflected to absorbed light governs the lightness of the color, or its value. The preferential absorption of certain wavelengths by natural pigments (such as iron oxide and hydrous iron oxide) disseminated through the flint determine the hue of the color.
The color changes produced during patination relate to changes in texture and impurity content occasioned by the attack of weathering agents on impurities in the flint. The creation of voids by the dissolution and leaching of carbonates, the loosening of quartz crystallites, and the dispersal of clays all modify the reflectivity of the flint. Chemical changes involving the pigments, their dispersal along intergranular surfaces, or removal by leaching modify both reflectivity and capacity to preferentially absorb.
Attempts to correlate patina thickness with age, and thus to use flint patinae chronometrically, have proven unsatisfactory because other factors, whose importance in some cases exceeds that of age, have not been taken into account. The texture and microstructure of flint, its permeability, and the kind, proportion, and distribution of impurities can be evaluated by regular petrographic techniques. Environmental factors can be assumed constant for artifacts from the same types of soil in a given climatic region. Only after allowances have been made for these additional variables does the age-dependence of flint patination become clear.
Nuclear Magnetic Resonance Spectroscopy in Superconducting Magnetic Fields
Authors: Nelson F. A. , Weaver H. E. 
Published: October 2006

The first high-resolution nuclear magnetic resonance spectrometer operated at 30 Mcy/sec (7.05 kilogauss). The magnets constituted the only major obstacle to raising the frequency, but by continuous development over 10 years this frequency for proton resonance was increased to 100 Mcy/sec (23.4 kilogauss). Now, in one step, a system has been made to operate at twice this frequency and field intensity. It is not expected that superconducting magnets will generally replace iron magnets, but it is interesting to note that very few laboratories use the 30- and 40-Mcy/sec proton systems today.
Notwithstanding the cost and operating problems of the superconducting magnet system for the nuclear magnetic resonance spectrometer, the fact that this is the only practical means of developing both a stable and a high-intensity field puts it in a class by itself. For this reason, even though the maintenance of spectrometers with superconducting magnets requires rather specialized skills, this type of instrumentation will clearly have an important role in advancing scientific knowledge, by making possible analyses which have not been possible with presently available instruments.
Mechanism of Polarized Light Perception
Authors: Waterman Talbot H. , Horch Kenneth W. 
Published: October 2006

As background for a report on our current selective adaptation experiments in decapod crustaceans, the various facts and hypotheses generally relevant to intraretinal sensitivity to polarized light in arthropods as well as cephalopods have been marshaled. On the basis of this review, the following working hypotheses have been made.
1) One ommatidium in the compound eye is the functional unit in image perception but contains in its component retinular cells subunits which can work independently in detecting other visual parameters, such as polarization.
2) Single retinular cells do respond differentially to light polarized in various planes.

3) Light sensitivity, including
e
-vector detection, is localized in the rhabdomeres, which comprise closely packed arrays of microvilli protruding axially from retinular cells; the dichroism of the photopigment molecules, which are contained within the microvilli, provides the molecular basis of
e
-vector detection.

4) The visual pigment molecules have their major dichroic axis aligned predominantly parallel to the long axis of the microvillus containing them; typically all microvilli in a single rhabdomere are closely parallel to one another, thus comprising at the cellular level a unit dichroic analyzer with maximum optical density to photons vibrating in the direction parallel to these microvillous protrusions.

5) In most decapod crustaceans, in cephalopods, and in some insects the microvilli in all rhabdomeres of a retinula are oriented in only two directions, perpendicular to each other. Therefore,
e
-vector perception must depend at the retinular level on a two-channel system consisting of a pair of dichroic analyzers with their major transmitting axes fixed at a 90° angle determined by the two directions of microvillus orientation.

Our new results on selective adaptation in the eye of
Cardisoma
provide direct experimental evidence for such a two-channel analyzer in which the pair of functional units have their maximum sensitivity to polarization in the same retinal directions as the rhabdom microvilli observed in electron micrographs. In turn, these directions correspond with the vertical and horizontal axes of the animal's normal spatial orientation. In
e
-vector detection the seven retinular cells of a single decapod ommatidium thus form two operational subgroups of four and three cells, respectively. The correspondence of the electrophysiological evidence for a dual polarization analyzer with the perpendicular directions shown by the microvilli in a single rhabdom strengthens the idea that one ommatidium is enough for detecting
e
-vector orientation.

On this evidence we may conclude that the model developed above for a two-channel polarization analyzer effectively accounts for the relevant spectrophotometric, fine-structural, electrophysiological, and behavioral data currently available for a considerable number of arthropods and cephalopods.
Scaling Data on Inter-Nation Action
Authors: Moses Lincoln E. , Brody Richard A. , Holsti Ole R. , Kadane Joseph B. , Milstein Jeffrey S. 
Published: October 2006

We conclude (i) that the marker-card method is as reliable a measure as the ordinary Q-sort method; (ii) that Q and the marker-card score are measuring very nearly the same thing—in this case, presumably conflict; and (iii) that the use of marker cards permits comparison of judgments about a given quantity in the context of different situations and may even permit comparison of results obtained by different research teams if the different teams use the same marker decks.
A fundamental issue involved in scoring the entries on the cards in this study by either Q-sort or marker cards is the "judgability" of the items as indicators of conflict. We noted above that items with the highest variances in scoring, from judge to judge, were concentrated at the low-conflict end of the scale. A possible explanation is that judges are able to make finer distinctions concerning an attribute when it is present than when it is absent. Differences in scoring could also arise from a lack of unidimensionality in the attribute being scaled. If judges find that conflict has several distinct aspects, the task of placing items in a single order becomes more difficult.
Difficulties in making judgments also arose from the fact that the actions were being judged out of context, or in contexts that varied from judge to judge, since no standard context was supplied. But these difficulties lie outside our problem, which was to find an alternative to Q-sorting which would permit intersituational comparisons. Our success in finding an alternative is apparent in our results, but problems of judgability remain with both techniques.
Beyond providing a standard for intersituational comparisons, the marker-card technique has other advantages. It is possible that the use of marker decks will be of help in training judges to score such a variable as conflict. In our study it permitted identification of a judge inadequately trained to do so. Possibly the marker cards will be useful in assigning scale values to batches of data too small for Q-sort, or even to individual items. It further appears that the marker cards should be useful in discriminating among high-conflict items which heretofore would all have tended to appear in the top Q-sort category.
The marker-card technique has given us a reliable alternative to Q-sort for scaling conflict. The method should be capable of extension to dimensions other than conflict.
Polyester Fiber: From Its Invention to Its Present Position
Authors: Brown Alfred E. , Reinhart Kenneth A. 
Published: October 2006

The use of polyester fibers has grown more rapidly than that of any other man-made fiber. Many factors have contributed to this growth. Polyester's unique physical properties of strength, high modulus, elasticity, and durability are the basis for its success. The tailorability of the fiber makes it possible to generate a whole family of property variants for a wide variety of end uses. The ready availability and low cost of the raw materials, the continuing advances in polymerization technology, and the versatility of the melt spinning process have also been major factors in establishing polyester as the leading man-made fiber.
New end uses have had a major impact on the growth of polyester. Most notable was the introduction of durable press fabrics for clothing and home furnishings. The consumer preference for easy-care fabrics and garments makes the durable press area one of continuing growth. Two relatively new areas where growth is expected to continue at a rapid rate are tire cord and textured knits for women's and men's outerwear.
Protection of Privacy and Confidentiality
Authors: Curran William J. , Kaplan Honora , Laska Eugene M. , Bank Rheta 
Published: October 2006

A multistate, cooperative program seeking to develop better methods for the effective and efficient gathering. storing, analyzing, and utilizing of mental patient records has made a comprehensive effort to protect the confidentiality and privacy of these psychiatric patient records. Administrative, technical, and legal safeguards have been implemented. The discussion of legal safeguards involves two areas: the protection of the system itself, located at Rockland State Hospital; and the specific legal environment of confidentiality and privacy of mental health records and information in the group of cooperating jurisdictions.
On the whole, adequate legal and administrative protection can be afforded the confidentiality and privacy of an electronic data system in the mental health field, and access to the records can be restricted for the welfare of the patients. At the same time, access to aggregate data in the system can be allowed, under proper standards, for important research and planning purposes. The methods adopted by MSIS to preserve confidentiality and privacy by limiting access to such records could well prove an important model for the development of protective methods in other electronic data programs—not only those in psychiatry, but those in other fields where the data collected are sensitive and confidential.
Multienzyme Systems of DNA Replication
Authors: Schekman Randy , Weiner Alan , Kornberg Arthur 
Published: October 2006

Replication is accomplished by multienzyme systems whose operations are usefully considered in respect to three stages of the process: initiation, elongation, and termination.

1) Initiation entails synthesis of a short RNA fragment that serves as primer for the elongation step of DNA synthesis. This stage, probed by SS phage DNA templates, reveals three distinctive and highly specific systems in
E. coli
. The Ml3 DNA utilizes RNA polymerase in a manner that may reflect how plasmid elements are replicated in the cell. The φX174 DNA does not rely on RNA-polymerase, but requires instead five distinctive proteins which may belong to an apparatus for initiating a host chromosome replication cycle at the origin. The G4 DNA, also independent of RNA polymerase, needs simply the
dna
G protein for its distinctive initiation and may thus resemble the system that initiates the replication fragments at the nascent growing fork. In each case it is essential that in vitro the DNA-unwinding protein coat the viral DNA and influence its structure.

2) Elongation is achieved in every case by the multisubunit, holoenzyme form of DNA polymerase III. Copolymerase III, which is an enzyme subunit, and adenosine triphosphate are required to form a proper complex with the primer template but appear dispensable for the ensuing chain growth by DNA polymerase.
3) Termination requires excision of the RNA priming fragment, filling of gaps and sealing of interruptions to produce a covalently intact phosphodiester backbone. DNA polymerase I has the capacity for excision and gap-filling and DNA ligase is required for sealing.
What once appeared to be a simple DNA polymerase-mediated conversion of a single-strand to a duplex circle is now seen as a complex series of events in which diverse multienzyme systems function. Annoyance with the difficulties in resolving and reconstituting these systems is tempered by the conviction that these are the very systems used ,by the cell in replicating its chromosome and extrachromosomal elements. Thus, understanding of the regulation of replication events in the cell, their localization at membrane surfaces and integration with cell division, and their coordination with phage DNA maturation and particle assembly will all be advanced by knowledge of the components of the replicative machinery.