bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermal behavior and intermolecular interactions in blends of poly(3‐hydroxybutyrate) and maleated poly(3‐hydroxybutyrate) with chitosan
Authors: Chen Cheng , Zhou Xuesong , Zhuang Yugang , Dong Lisong 
Published: November 2004

AbstractThe thermal behavior and intermolecular interactions of blends of poly(3‐hydroxybutyrate) (PHB) and maleated PHB with chitosan were studied with differential scanning calorimetry, Fourier transform infrared (FTIR), wide‐angle X‐ray diffraction (WAXD), and X‐ray photoelectron spectroscopy (XPS). The differences in the two blend systems with respect to their thermal behavior and intermolecular interactions were investigated. The melting temperatures, melting enthalpies, and crystallinities of the two blend systems gradually decreased as the chitosan content in the blends increased. Compared with that of the PHB component with the same composition, the crystallization of the maleated PHB component was more intensively suppressed by the chitosan component in the blends because of the rigid chitosan molecular chains and the intermolecular hydrogen bonds between the components. FTIR, WAXD, and XPS showed that the intermolecular hydrogen bonds in the blends were caused by the carbonyls of PHB or maleated PHB and chitosan aminos, and their existence depended on the compositions of the blends. The introduction of maleic anhydride groups onto PHB chains promoted intermolecular interactions between the maleated PHB and chitosan components. In addition, the intermolecular interactions disturbed the original crystal structures of the PHB, maleated PHB, and chitosan components; this was further proven by WAXD results. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 35–47, 2005
Truncated E‐cadherin potentiates cell death in prostate epithelial cells
Authors: Rios‐Doria Jonathan , Day Mark L. 
Published: November 2004

AbstractBACKGROUNDE‐cadherin, a fundamental component of the adherens junction, is known to mediate aggregation‐dependent cell survival. We have previously identified a novel, calpain‐dependent proteolytic cleavage of E‐cadherin that resulted in the generation of a stable 100‐kDa E‐cadherin fragment (E‐cad100) in prostate epithelial cells in response to cell death stimuli. We postulated that the E‐cad100 fragment may play a role in abrogating survival of LNCaP cells following induction of apoptosis.METHODSWild‐type E‐cadherin and E‐cad100 were engineered, tagged with GFP, and stably expressed in LNCaP cells. These cell lines were characterized for E‐cadherin‐GFP/β‐catenin interactions, endogenous E‐cadherin and β‐catenin expression, and sensitivity to apoptosis induced by PKC activation.RESULTSE‐cad100‐GFP demonstrated a punctuate expression pattern, in contrast to E‐cad120‐GFP, which was membrane‐localized. E‐cad100‐GFP, unlike E‐cad120‐GFP, failed to bind to and co‐localize with β‐catenin. Transient or stable overexpression of E‐cad100 resulted in the downregulation of endogenous E‐cadherin expression at the cell membrane. Activation of PKC in LNCaP cells which overexpressed E‐cad100 potentiated cell death.CONCLUSIONSTruncated E‐cadherin may play a role in the regulation of endogenous E‐cadherin expression and epithelial cell survival. © 2004 Wiley‐Liss, Inc.
Fragmentation of N‐linked glycans with a matrix‐assisted laser desorption/ionization ion trap time‐of‐flight mass spectrometer
Authors: Harvey David J. , Martin Rachel L. , Jackson Kathryn A. , Sutton Chris W. 
Published: November 2004

AbstractN‐Linked glycans were ionized from several matrices with a Shimadzu‐Biotech AXIMA‐QIT matrix‐assisted laser desorption/ionization quadrupole ion trap time‐of‐flight mass spectrometer. [M+Na]+ ions were produced from all matrices and were accompanied by varying amounts of in‐source fragmentation products. The least fragmentation was produced by 2,5‐dihydroxybenzoic acid and the most by α‐cyano‐4‐hydroxycinnamic acid and 6‐aza‐2‐thiothymine. Sialic acid loss was extensive but could be prevented by formation of methyl esters. Fragmentation produced typical low‐energy‐type spectra dominated by ions formed by glycosidic cleavages. MSn spectra (n = 3 and 4) were used to probe the pathways leading to the major diagnostic ions. Thus, for example, an ion that was formed by loss of the core GlcNAc residues and the 3‐antenna was confirmed as being formed by a B/Y rather than a C/Z mechanism. The proposed structures of several cross‐ring cleavage ions were confirmed and it was shown that MS3 spectra could be obtained from as little as 10 fmol of glycan. Copyright © 2004 John Wiley & Sons, Ltd.
Acetylcholinesterase activity as a marker of maturation of the basolateral complex of the amygdaloid body in the rat
Authors: Berdel Bożena , Moryś Janusz , Maciejewska Beata , Narkiewicz Olgierd 
Published: November 2004

AbstractDevelopment and maturation of the basolateral complex of the amygdaloid body were studied in fetal and postnatal rat brains. In cresyl violet‐stained sections the basolateral complex was distinguishable at the 17th prenatal day. On about the 14th postnatal day, it showed all the features of the adult structure. The acetylcholinesterase activity appeared in neuropil of the basolateral complex on the seventh postnatal day; it increased slowly up to the 60th day. After that age, the acetylcholinesterase activity was stable in all parts of the basolateral complex and corresponded to its cytoarchitectonic differentiation. Our results suggest that the process of maturation of the amygdaloid basolateral complex, being related to the ingrowing of the cholinergic fibers from the basal forebrain, lasts at least up to the end of the second month of postnatal life.
Studies of embryonic development and the reproductive cycle in ovoviviparous Australian Onychophora (Peripatopsidae)
Authors: Walker Muriel H. , Tait Noel N. 
Published: November 2004

AbstractEmbryos of four ovoviviparous species of Australian onychophorans were examined to establish the process of their development, their reproductive cycle and to estimate the gestation period. The process of development is the same in all four species with, in the early embryo, segment halves separated by broad bands of extra‐embryonic ectoderm and the embryos growing by the posterior addition of segments. Seven developmental stages (I–VII) can be clearly identified from external morphology. Analysis of the developmental stages of the embryos present in females collected throughout a calendar year has allowed estimation of the time taken for each developmental stage and demonstrated that there is an annual reproductive cycle with a total gestation period of c. 12 months. Stages I and VII are prolonged, the latter related to the late completion of midgut development. The simultaneous presence of stage I and stage VII embryos at certain times of year indicates an overlap of generations within the uteri, which is more extensive for some species than others. As the stage VII embryos of one cohort complete their development, enlarged oocytes are released from the ovaries to become fertilized as they pass the seminal receptacles and enter the uteri to start their embryonic development to form the next cohort. Cephalofovea clandestina, Phallocephale tallagandensis and Ruhbergia bifalcata have head structures in males, Euperipatoides rowelli does not. The presence of embryos at all times of year in the uteri of mature females has implications for mating and sperm storage that are discussed.
The biology and functional morphology of Nipponoclava gigantea: clues to the evolution of tube dwelling in the Penicillidae (Bivalvia: Anomalodesmata: Clavagelloidea)
Authors: Morton Brian 
Published: November 2004

Abstract Nipponoclava gigantea is restricted to the tropical Western Pacific waters of southern Japan at depths of between 5 and 70 m and lives in coarse sand and gravel. In many respects, N. gigantea appears to be similar to other endobenthic penicillids in that there is a true shell, the margins of which, via the intermediary of a narrow ‘saddle’, are united with an adventitious tube. This has a large watering pot anteriorly and pleated ruffles, representing either growth or repair events, posteriorly. Nipponoclava gigantea differs from other penicillids, however, in that its true shell is large, i.e. ˜20 mm high as compared to 2–3 mm, and the angle of valve splay is ˜80° as opposed to 180°. Internally the shell has a wide pallial line and shallow pallial sinus and there are anterior adductor muscle scars. There are possibly posterior adductor muscle scars also. These are not present in the adult animal, however, although the anterior adductor is. Also present are paired anterior and (possibly) posterior pedal retractor muscles, the latter having a nervous union with the visceral ganglia to create simple stretch or tonus proprioreceptors. It is argued that N. gigantea provides clues about how the tube‐dwelling lifestyle has evolved in the various taxa of the Penicillidae. It is suggested that through a process of heterochrony, in which the animal produces its adventitious tube at progressively earlier and earlier developmental stages, the true shell has become actually and relatively smaller and smaller and, hence, more splayed in more derived penicillids. Nipponoclava gigantea is thus an important link between an hypothetical lyonsiid ancestor and the more specialized penicillids and helps us to understand the adaptive radiation of this group of tube‐dwelling bivalves.
A novel Na+ channel agonist, dimethyl lithospermate B, slows Na+ current inactivation and increases action potential duration in isolated rat ventricular myocytes
Authors: Yoon Jin‐Young , Ahn Sung‐Hun , Oh Hyuncheol , Kim Young‐Sup , Ryu Shi Yong , Ho Won‐Kyung , Lee Suk‐Ho 
Published: November 2004

Voltage‐gated Na+ channel blockers have been widely used as local anaesthetics and antiarrhythmic agents. It has recently been proposed that Na+ channel agonists can be used as inotropic agents. Here, we report the identification of a natural substance that acts as a Na+ channel agonist.
Using the patch‐clamp technique in isolated rat ventricular myocytes, we investigated the electrophysiological effects of the substances isolated from the root extract of Salvia miltiorrhiza, which is known as ‘Danshen’ in Asian traditional medicine. By the intensive activity‐guided fractionation, we identified dimethyl lithospermate B (dmLSB) as the most active component, while LSB, which is the major component of the extract, showed negligible electrophysiological effect. Action potential duration (APD90) was increased by 20 μM dmLSB from 58.8±12.1 to 202.3±9.5 ms. In spite of the prolonged APD, no early after‐depolarization (EAD) was observed.
dmLSB had no noticeable effect on K+ or Ca2+ currents, but selectively affected Na+ currents (INa). dmLSB slowed the inactivation kinetics of INa by increasing the proportion of slowly inactivating component without inducing any persistent INa. The relative amplitude of slow component compared to the peak fast INa was increased dose dependently by dmLSB (EC50=20 μM). Voltage dependence of inactivation was not affected by dmLSB, while voltage dependence of activation shifted by 5 mV to the depolarised direction.
Since the APD prolongation by dmLSB did not provoke EAD, which is thought as a possible mechanism for the proarrhythmia seen in other Na+ channel agonists, dmLSB might be an excellent candidate for a Na+ channel agonist.

British Journal of Pharmacology (2004) 143, 765–773. doi:10.1038/sj.bjp.0705969
Electrophysiological characterization of the SK channel blockers methyl‐laudanosine and methyl‐noscapine in cell lines and rat brain slices
Authors: Scuvée‐Moreau Jacqueline , Boland Andre , Graulich Amaury , Overmeire Lionel Van , D'hoedt Dieter , Graulich‐Lorge Fabienne , Thomas Elizabeth , Abras Aude , Stocker Martin , Liégeois Jean‐Francois , Seutin Vincent 
Published: November 2004

We have recently shown that the alkaloid methyl‐laudanosine blocks SK channel‐mediated afterhyperpolarizations (AHPs) in midbrain dopaminergic neurones. However, the relative potency of the compound on the SK channel subtypes and its ability to block AHPs of other neurones were unknown.
Using whole‐cell patch‐clamp experiments in transfected cell lines, we found that the compound blocks SK1, SK2 and SK3 currents with equal potency: its mean IC50s were 1.2, 0.8 and 1.8 μM, respectively. IK currents were unaffected. In rat brain slices, methyl‐laudanosine blocked apamin‐sensitive AHPs in serotonergic neurones of the dorsal raphe and noradrenergic neurones of the locus coeruleus with IC50s of 21 and 19 μM, as compared to 15 μM in dopaminergic neurones. However, at 100 μM, methyl‐laudanosine elicited a constant hyperpolarization of serotonergic neurones of about 9 mV, which was inconsistently (i.e. not in a reproducible manner) antagonized by atropine and hence partly due to the activation of muscarinic receptors.
While exploring the pharmacology of related compounds, we found that methyl‐noscapine also blocked SK channels. In cell lines, methyl‐noscapine blocked SK1, SK2 and SK3 currents with mean IC50s of 5.9, 5.6 and 3.9 μM, respectively. It also did not block IK currents. Methyl‐noscapine was slightly less potent than methyl‐laudanosine in blocking AHPs in brain slices, its IC50s being 42, 37 and 29 μM in dopaminergic, serotonergic and noradrenergic neurones, respectively. Interestingly, no significant non‐SK effects were observed with methyl‐noscapine in slices. At a concentration of 300 μM, methyl‐noscapine elicited the same changes in excitability in the three neuronal types than did a supramaximal concentration of apamin (300 nM).
Methyl‐laudanosine and methyl‐noscapine produced a rapidly reversible blockade of SK channels as compared with apamin. The difference between the IC50s of apamin (0.45 nM) and methyl‐laudanosine (1.8 μM) in SK3 cells was essentially due to a major difference in their k−1 (0.028 s−1 for apamin and 20 s−1 for methyl‐laudanosine).
These experiments demonstrate that both methyl‐laudanosine and methyl‐noscapine are medium potency, quickly dissociating, SK channel blockers with a similar potency on the three SK subtypes. Methyl‐noscapine may be superior in terms of specificity for the SK channels.

British Journal of Pharmacology (2004) 143, 753–764. doi:10.1038/sj.bjp.0705979
Evidence for an apamin‐sensitive, but not purinergic, component in the nonadrenergic noncholinergic relaxation of the rat gastric fundus
Authors: Currò Diego , Marco Teresina De , Preziosi Paolo 
Published: November 2004

The involvement of adenosine triphosphate (ATP) and carbon monoxide (CO) in the non‐nitrergic nonpeptidergic component of high‐frequency electrical field stimulation (EFS)‐induced nonadrenergic noncholinergic (NANC) relaxation of longitudinal muscle strips from the rat gastric fundus was investigated.
Under NANC conditions (1 μM atropine+5 μM guanethidine), NG‐nitro‐L‐arginine methyl ester (L‐NAME, 1 mM) slightly reduced the amplitude, but did not affect the area under the curve (AUC) of EFS (13 Hz, 2 min)‐induced relaxation of 9,11‐dideoxy‐9α,11α‐methanoepoxy prostaglandin F2α (U46619, 0.1 μM)‐precontracted strips. With L‐NAME (1 mM) plus α‐chymotrypsin (1 U ml−1), the amplitude and the AUC of relaxation were reduced to approximately two‐third and one‐third of controls, respectively.
Pyridoxal‐phosphate‐6‐azophenyl‐2′,4′‐disulphonic acid (100 μM), apamin (0.3 μM), desensitization to ATP, suramin (100 μM), zinc protoporphirin IX (300 μM) or ferrous haemoglobin (100 μM) did not inhibit the component of relaxation resistant to L‐NAME plus α‐chymotrypsin.
L‐NAME (1 mM) plus anti‐vasoactive intestinal peptide (VIP) serum (1 : 100) reduced the amplitude and the AUC of relaxation to a similar extent as L‐NAME (1 mM) plus α‐chymotrypsin (1 U ml−1). Adding apamin (0.1 μM) to L‐NAME (1 mM) plus anti‐VIP serum (1 : 100) further reduced the amplitude and the AUC of relaxation.
These findings suggest that the non‐nitrergic nonpeptidergic component of NANC relaxation of the rat gastric fundus induced by high‐frequency stimulation is mediated by a neurotransmitter thatacts through apamin‐sensitive mechanisms, that is neither ATP nor CO.

British Journal of Pharmacology (2004) 143, 785–793. doi:10.1038/sj.bjp.0705993
Protein kinase C activation inhibits eosinophil degranulation through stimulation of intracellular cAMP production
Authors: Ezeamuzie Charles I , Taslim Najla 
Published: November 2004

The mechanism of inhibition of eosinophil degranulation by protein kinase C (PKC) was investigated in complement C5a (C5a)‐stimulated degranulation of highly purified human eosinophils using the specific PKC activator – phorbol 12‐myristate 13‐acetate (PMA).
C5a‐induced release of eosinophil peroxidase and eosinophil cationic protein was potently inhibited in a concentration‐dependent manner by PMA (IC50: 3 and 5 nM, respectively). The inhibition by PMA, but not histamine, was significantly reversed by the specific, but isoform nonselective, PKC inhibitor Ro 31‐8220 (1 μM).
In the presence of phosphodiesterase inhibitor rolipram (5 μM), PMA stimulated a pronounced concentration‐dependent increase in intracellular cAMP, with a potency 400 times that of histamine (EC50: 55 nM vs 22.5 μM). The inactive PMA analogue, 4α‐PMA, had no such effect.
The cAMP production by PMA, but not histamine, was significantly reversed by Ro 31‐8220 (1 μM) and the selective inhibitor of the novel PKCδ, rottlerin (1–3 μM), but not the selective inhibitor of the classical PKC isoforms, Gö 6976 (0.01–0.1 μM).
Western blot analysis revealed the presence of six PKC isoforms (α, βI, βII, δ, ι and ζ) in isolated eosinophils.
Chelation of internal or external calcium had no effect on PMA‐induced cAMP response, but abolished that induced by histamine.
There was a good correlation between increase in intracellular cAMP and inhibition of degranulation.
These results show, for the first time, that in human eosinophils, PMA, via activation of PKCδ isoform, can stimulate cAMP production, and that this may be the basis for its potent anti‐degranulatory effect.

British Journal of Pharmacology (2004) 143, 725–732. doi:10.1038/sj.bjp.0706028
Revisiting Evander atAeneid8.363
Authors: Rees Roger 
Published: November 2004

The purpose of this note is to revive Servius Auctus' interpretation ofAeneid8.363, which has been overlooked or dismissed without argument by recent scholars. It concerns the identification and location of Evander'sregia. The relevant lines are worth quoting in full (359–67):There has been general agreement amongst scholars this century that the building is to be understood to be occupying the same place—or thereabouts—as that later to be taken by Augustus' house. It is now established that this was on the South-West of the Palatine.
Martial 14.100: Panaca
Authors: Leary T. J. 
Published: November 2004

The wine referred to in the second line of the epigram was produced near Verona, at the foot of the Rhaetian Alps. It was well regarded by most and was a favourite of the Emperor Augustus: for references see Mynors at Verg. G. 2.96 and my note at Mart. 14.100.2. It appears, however, to have undue prominence in this poem, supposedly about the earthenware drinking vessels which, presumably, were
manufactured in the same area.There is also the question of why Martial refers to Verona in such a circumlocutory way. Is he merely following a well established elegiac/epigrammatic convention in associating Verona with Catullus (cf. e.g. Ovid, Am. 3.15.7 and Mart. 1.7.2), or does his circumlocution here have any particular point?
Plato's Disappointment with his Phaedran Characters and its Impact on his Theory of Psychology
Authors: Tomin Julius 
Published: November 2004

In the Phaedrus scientific psychology is an integral part of Plato's outline of scientific rhetoric. An accomplished rhetorician must know all types of human souls (ψυχς γένη, 271b1–2), he must know what kind of soul is affected by what kind of speech, and he must be able to apply this theoretical knowledge in front of an audience, so as to achieve the intended persuasion with unfailing certainty. This knowledge is an essential qualification of a philosopher; it enables him to choose a soul of the right type (λαβῲν ψνχήν προσήκουσαν, 276e6) and plant in it words of wisdom. His words, that is the authentic logos, acquire new life in the soul of the recipient, who in his turn sows their progeny in other suitable souls (276e5–277a3). In the dialogue, Socrates implants the words of wisdom in the soul of Phaedrus, and wishes that Phaedrus may similarly influence Lysias (257ab).Socrates’ work on Phaedrus permeates the whole dialogue, giving it its dramatic unity, and yet interpreters disagree on it. The late dating of the dialogue, which has been accepted as axiomatic throughout this century, stands in the way of seeing it clearly. Phaedrus in the Protagoras and in the Symposium does not appear like a man who would appropriate the exalted ideal raised before him in the Phaedrus. The majority of modern interpreters therefore cannot see Phaedrus’ conversion to philosophy in the Phaedrus as anything but ironic. I shall argue that Plato in the dialogue does enact his Phaedran ideal of the authentic communication of philosophy, and that this precludes the ironical reading of the dialogue.
Aristotle, Speusippus, and the method of division
Authors: Falcon Andrea 
Published: November 2004

IntroductionAs Aristotle himself says,A.Po.2.13 is an attempt to provide some rules to hunt out the items predicated in what something is, namely to discover definitions. Since most of this chapter is devoted to the discussion of some rules of division(diairesis), it may be inferred that somehow division plays a central role in the discovery of definitions. However, in the following pages I shall not discuss what this role is. Nor shall I discuss what place division has in the wider discussion of definition and explanation as it emerges fromA.Po. 2.1 shall rather focus on the argument that Aristotle reports and discusses inA.Po.2.13.97a6–22, and which our extant sources ascribe to Speusippus. As will become clear later on, this argument undermines the possibility of giving any definition, and Aristotle deals with it here because he can block it by exploiting some properties of the method of division.
Two textual problems in Aristophanes
Authors: Wilson N. G. 
Published: November 2004

In 1023ff. the poet explains that he has not been spoiled by success. The verb ༐κτελσαι in 1024 has been suspected, and though recent editors accept it, taking it as absolute, I am far from convinced that it is what the author wrote. Blaydes, in his usual fashion, records conjectures and makes some of his own, but though he hits the mark quite often in Aristophanes as he does in Sophocles, in this passage his efforts, e.g. ༐κγελσαι, fail to satisfy. I propose instead ༐κχαλσαι, ‘relax’. It might be transitive, but I slightly prefer to take it as intransitive. It is a rare word and all the more likely to be corrupted. The best parallel I can find is Hippocrates, De Octimestri Partu 1.2 (ed. Joly, 5 ed. Grensemann): οἱυες ༐υ oἶσι τυ ρχυ ༐τρøη, ὣσπερ τυ σταχωυ, ζεχλασαυ πρσθευ υαγκαζώμευου 祴 τελεως ζαδρυυθυαι τυ καρπυ.The verb is correctly transmitted in the best MS, Marc.gr. 269, while the other main source of the treatise, Vat.gr. 276, offers ζεκλεσαυ9, which is clearly due to an error by a scribe who did not recognize the unusual word required by the context. As to the date of this treatise, it is believed by one of the best modern authorities to be no later than the end of the fifth century and is therefore nearly contemporary with Aristophanes.