bluuebunny/crossref_metadata_2025 huggingface dataset:
MHC Class II Allosteric Site Drugs: New Immunotherapeutics for Malignant, Infectious and Autoimmune Diseases*
Authors: Xu M. , Li J. , Gulfo J. V. , Von Hofe E. , Humphreys R. E.
Published: March 2003

The discovery of the interactions of the ‘Ii‐Key’ segment of the Ii protein with the major histocmpatibility complex (MHC) Class II allosteric site, which is adjacent to the antigenic peptide‐binding site, creates therapeutic opportunities by regulating the antigenic peptide binding to MHC class II molecules. The binding of Ii‐Key to the MHC class II allosteric site loosens the hold of the MHC Class II ‘clamshell’ on antigenic peptides and leads to highly efficient antigenic peptide charging to or releasing from the MHC class II antigenic peptide‐binding groove. Ii‐Key peptide‐induced spilling of bound antigenic peptide, or replacement with inert blockers, leads to ‘inert immunosuppression’. Highly efficient replacement of ambient with vaccine peptides by Ii‐Key permits ‘active immunosuppression’ for antigen‐specific control of autoimmune diseases in the absence of cytokines or adjuvants. On the other hand, active immunization against cancer or infectious disease can result from epitope replacement mediated by Ii‐Key and accompanied by cytokines or other adjuvants. Finally, linking the Ii‐Key peptide through a simple polymethylene bridge to an antigenic sequence vastly increases the potency of MHC Class II peptide vaccines. In summary, the discovery of the MHC class II allosteric site allows one to increase the efficiency of MHC class II‐related, antigenic epitope‐specific therapy for malignant, infectious, and autoimmune diseases. The focus of this review is on the mechanism and potential clinical use of such novel allosteric site‐directed, Ii‐key drugs.
Human and Murine Humoral Immune Recognition of Multiple Peptides from Schistosoma mansoni Glyceraldehyde 3‐P Dehydrogenase is Associated with Resistance to Schistosomiasis
Authors: El Ridi R. , Mahrous A. , Afifi A. , Montash M. , Velek J. , Ježek J.
Published: March 2003

Schistosoma mansoni glyceraldehyde 3‐phosphate dehydrogenase (SG3PDH) is a target of cellular and humoral immune responses of Brazilian and Egyptian subjects putatively resistant to reinfection with S. mansoni. In an aim to develop a safe, stable and effective vaccine based on this promising molecule, six peptides derived from its primary sequence were selected based on the lowest homology to human G3PDH. The synthetic peptides were tested by ELISA against plasma of humans putatively susceptible or resistant to reinfection with S. mansoni or S. haematobium following chemotherapeutic cure of previous infection. Repeat experiments indicated that the six peptides bear human B‐cell epitopes that bind immunoglobulin (Ig)M, IgG1 and IgG3 antibodies. Resistance to reinfection appeared to be significantly associated with humoral immune responses to multiple peptides. This contention was supported by studies in the murine model, whereby we examined the B cell immune responses of Swiss and inbred BALB/c and C57BL/6 mice immunized with recombinant SG3PDH (rSG3PDH) to the six SG3PDH‐derived peptides. The serum antibodies of rSG3PDH‐immunized Swiss mice were directed to only one of the six peptides tested by ELISA. Antibodies from rSG3PDH‐immunized C57BL/6 and BALB/c mice bound, respectively, to four and six out of six peptides. In contrast to Swiss mice, immunization of C57BL/6 and BALB/c mice with rSG3PDH induced protection against challenge cercariae which reached the level of significance (P < 0.05) for BALB/c mice. The data together indicate that host recognition of multiple peptides of a candidate vaccine antigen is necessary for the expression of its ability to contribute to protective immunity against Schistosomiasis.
Associations of MHC Class II Alleles in Norwegian Primary Sjögren's Syndrome Patients: Implications for Development of Autoantibodies to the Ro52 Autoantigen
Authors: Nakken B , Jonsson R. , Brokstad K. A. , Omholt K. , Nerland A. H. , Haga H. J. , Halse A.‐K.
Published: March 2003

Sjögren's syndrome (SS) is a chronic autoimmune disease characterized by dryness of the eyes and mouth. Currently, the highly polymorphic major histocompatibility complex (MHC) genes are the best documented genetic risk factor for the development of autoimmune disease. We examined the MHC class II alleles DRB1, DRB3, DRB4, DRB5, DQA1 and DQB1 in a group of Norwegian pSS patients and compared with a group of healthy controls. Because a number of studies have shown that some of the MHC class II alleles are not associated with the disease as a whole, but rather to the development of autoantibodies, anti‐Ro52 autoantibodies in serum were measured and compared to MHC class II allele status. A clear association with pSS was detected for the DRB1*0301 and DRB3*0101 alleles, but these alleles were more closely associated with the presence of anti‐Ro52 autoantibodies than with pSS itself. Moreover, the DQA1*0501 and DQB1*0201 alleles were only associated with the presence of anti‐Ro52 autoantibodies. This study shows that the production of anti‐Ro52 autoantibodies in pSS is associated with the DRB1*0301, DRB3*0101, DQA1*0501 and DQB1*0201 alleles which are in strong linkage disequilibrium.
Importance of CpG Dinucleotides in Activation of Natural IFN‐α‐Producing Cells by a Lupus‐Related Oligodeoxynucleotide
Authors: Magnusson M. , Magnusson S. , Vallin H. , Rönnblom L. , Alm G. V.
Published: March 2003

The oligodeoxyribonucleotide (ODN) 5'‐TTTTCAATTCGAAGATGAAT‐3' (ODN H), identified in systemic lupus erythematosus (SLE) serum, induced the production of interferon (IFN)‐α in human peripheral blood mononuclear cells (PBMC) when combined with lipofectin. Flow cytometric analysis with staining for surface antigens and intracellular IFN‐α, showed that the IFN‐α‐producing cells (IPC) were the natural IPC, also termed type 2 dendritic cell precursors (pDC2) or plasmacytoid monocytes. The importance of unmethylated CpG dinucleotides for the interferogenic activity of ODN was studied. Methylation of CpG impaired the activity of single‐stranded (ss) ODN H, but increased that of the complementary ssODN I. Furthermore, CpG‐methylated double‐stranded (ds) ODN Hmet‐Imet lost, but hemimethylated dsODN H‐Imet retained interferogenic activity. Inversion of the CpG to GpC had no effect on the interferogenic activity of ssODN H, increased that of ssODN I, however abolished the activity of dsODN H‐I. Alteration of the CpG in ODN H to ApG and in the ODN I to CpT destroyed their activity. The induction of IFN‐α is therefore sequence‐specific, but unmethylated CpGs are not always required, especially not in ssODNs. Interferogenic DNA sequences could therefore be more frequent in eukaryotic genomes than previously thought and their capacity to activate natural IPC may have implications for immune responses to microbial antigens and nuclear autoantigens.
Expression and Function of CD22, a B‐cell Restricted Molecule*
Authors: MoyrOn‐QuirOz J. E. , Partida‐Sánchez S. , Donís‐Hernández R. , Sandoval‐Montes C. , Santos‐Argumedo L.
Published: March 2003

In this work, we studied the expression and function of CD22 in murine B cells. CD22 has been previously characterized as an activation marker of mature B lymphocytes. However, we found that CD22 is expressed early during the ontogeny of B cells in the bone marrow and spleen, and was found on B cells isolated from all the different lymphoid compartments. We also found that B cells stimulated through the B‐cell antigen receptor (BCR), CD38 and CD40, upregulated CD22 expression to maximal levels within 24 h after stimulation, but that the levels of CD22 declined at later times (48 and 72 h). CD22 is rapidly phosphorylated after BCR signal transduction, and is believed to downregulate B‐cell activation. In this study, we did not detect CD22 phosphorylation in activated B cells after CD38 or CD40 cross‐linking, even though CD22 was clearly phosphorylated in the BCR‐stimulated B cells. Consistent with this, we found no evidence of physical association between CD38 or CD40 and CD22 in B cells. The lack of association or phosphorylation of CD22 induced by CD38 and CD40 cross‐linking indicates that CD22 may not downregulate the activation induced by these two molecules.
Expansion of CD5 – B Cells in Multiple Sclerosis Correlates with CD80 (B7‐1) Expression
Authors: Sellebjerg F. , Jensen J. , Jensen C. V. , Wiik A.
Published: March 2003

The pathogenetic role of autoantibodies in multiple sclerosis (MS) is uncertain. CD5+ B cells commonly produce autoantibodies, but CD5 expression has also been implicated in B‐cell tolerance. We studied B‐cell subsets, anti‐myelin protein antibody‐secreting cells in cerebrospinal fluid (CSF) and a panel of serum autoantibodies in patients with clinically isolated syndromes (CIS), suggestive of MS and patients with clinically definite MS (CDMS). Patients with CDMS had a higher percentage of CD5– B cells in CSF than did control subjects (P = 0.02). CIS patients with immunoglobulin G (IgG) oligoclonal bands in CSF or multiple lesions on magnetic resonance imaging (MRI) had a higher percentage of CD5– B cells in CSF than did the remaining CIS patients (P = 0.03). The percentage of CD5– and CD80+ B cells correlated positively and the percentage of CD5+ B cells correlated negatively with the number of CSF cells secreting anti‐myelin basic protein (anti‐MBP) antibodies. The prevalence of serum autoantibodies was comparable in the three patient groups. We conclude that intrathecal expansion of CD5– B cells appears to be more characteristic in MS patients, and CD5+ B cells may be associated with a lower prevalence of anti‐myelin antibody production.
Genetic Aspects and Microenvironment Affect Expression of CD18 and VLA‐4 in Experimental Tuberculosis
Authors: BONATO V. L. D. , GONÇALVES E. D. C. , SANTOS R. R. , SILVA C. L.
Published: March 2003

Control of infection by Mycobacterium tuberculosis is dependent on macrophage activation and efficient migration of effector T‐cell populations. Lymphocyte differentiation is associated with changes in cell surface phenotype and alterations in the migratory pattern of these cells. In this study, we investigated the expression of adhesion receptors involved in activation and migration process in experimental tuberculosis. We observed that susceptible BALB/c mice infected with virulent M. tuberculosis by intraperitoneal route presented downmodulation of very late antigen 4 (VLA‐4) and unchanged levels of CD18 and CD44hi on peritoneal lymphocytes. On the other hand, lymphocytes from resistant C57BL/6 mice infected by the same route showed unchanged levels of VLA‐4 and upregulation of CD18 and CD44hi. However, when BALB/c mice were infected by intratracheal route, lung lymphocytes presented a different pattern of CD18, CD44hi and VLA‐4 expression from that observed on peritoneal cells, characterized by unchanged levels of VLA‐4 and upregulation of CD18 and CD44hi– coincidentally the same phenotype found on peritoneal cells from C57BL/6. These results suggest that susceptibility and resistance to M. tuberculosis infection, depending on the experimental model, are related to the expression of CD18, CD44hi and VLA‐4. Moreover, the microenvironment at the site of infection seems to differentially regulate the expression of these receptors. Thus, the up‐ or downmodulation of these adhesion receptors is probably associated with differential recruitment of T cells at the site of infection, which may or may not mediate protection in experimental tuberculosis.
Extensive and Preferential Fas/Fas Ligand‐Dependent Death of γδ T Cells Following Infection with Listeria monocytogenes
Authors: MUKASA A. , LAHN M. , FLEMING S. , FREIBERG B. , PFLUM E. , VOLLMER M. , KUPFER A. , O'BRIEN R. , BORN W.
Published: March 2003

In the spleens of mice infected intraperitoneally with the bacterium Listeria monocytogenes, both αβ and γδ T cells became rapidly activated, followed by a massive apoptotic death response predominantly within the γδ population. The death response involved two major splenic γδ T‐cell subsets and was Fas/Fas ligand (Fas‐L)‐dependent. Among T cells isolated from the Listeria‐infected spleen, Fas‐L was almost exclusively expressed in γδ T cells. γδ T cells coexpressed Fas and Fas‐L, suggesting activation‐induced suicide as a mechanism of their death. In vivo treatment with an antibody specific for CD3ε induced activation, preferential Fas‐L expression and apoptosis of γδ T cells, resembling the response pattern in listeriosis, whereas antibodies specific for T‐cell receptor‐β (TCR‐β) or TCR‐δ did not, suggesting that the complete response seen in listeriosis requires both γδ TCR engagement and additional stimuli. L. monocytogenes causes early nonspecific, Fas‐independent lymphocyte death in heavily infected tissues. In contrast, the death response described here is selective, Fas‐dependent and triggered at low local levels of bacteria, suggesting that it is controlled by interactions with other infection‐activated host cells, and perhaps part of a regulatory circuit specifically curtailing γδ T cells.
Characterization, Expression and Functional Aspects of a Novel Protein Tyrosine Phosphatase Epsilon Isoform
Authors: WABAKKEN T. , HAUGE H. , FUNDERUD S. , AASHEIM H.‐C.
Published: March 2003

This report describes the identification and characterization of a novel cytoplasmic isoform of human protein tyrosine phosphatase epsilon (PTPε). The novel isoform, denoted cyt‐PTPεPD1, displays only the N‐terminal catalytic, active phosphatase domain 1 (PD1) which is common in all known PTPε isoforms. In addition, it contains a unique 132‐residue long C‐terminal end with no known motifs or homology to other characterized proteins. RNAse protection assay on isolated leucocyte subpopulations and selected cell lines demonstrated highest expression of cyt‐PTPεPD1 in monocytes. The mRNA‐encoding cyt‐PTPεPD1 is detected as distinct transcript(s) by Northern blot analysis and is a result of alternative splicing. cyt‐PTPεPD1 shows similar cellular localization in transfected cells, both in the cytoplasm and nucleus, as has been previously described for cytoplasmic PTPε isoform. Our previous data suggest that the expression of cytoplasmic PTPε inhibits the mitogen‐activated protein kinase cascade through the extracellular signal‐regulated kinase 1 and 2 pathway. A similar functional role is also presented here for cyt‐PTPεPD1, supporting our previous data suggesting that the catalytic first PD of PTPε is responsible for this inhibition.
Increased Bcl‐2 and Reduced Bax Expression in Infected Macrophages in Slowly Progressive Primary Murine Mycobacterium tuberculosis Infection
Authors: MOGGA S. J. , MUSTAFA T. , SVILAND L. , NILSEN R.
Published: March 2003

Mycobacterium tuberculosis
(MTB) persists in host macrophages (Mφs) because it has developed mechanisms to escape Mφ killing.
In vitro
studies have shown that MTB can induce and inhibit apoptosis by causing the expression of Bax and Bcl‐2, respectively, suggesting that the infected cells' fate depends on pro‐ and antiapoptotic signals. In the present study, we investigated the role of Bcl‐2 in MTB infection
in situ
. The aim was to study the pattern and distribution of Bcl‐2 and Bax in cellular infiltrates of MTB‐infected B6D2F1 hybrid mice and correlate the expression with the presence of MTB antigens (MAgs). Using formalin‐fixed lung tissues (
n
 = 45), our results showed a significant difference in the percentage of Mφs stained for Bcl‐2 or MAgs and Bax (
P  < 0.0001). Bcl‐2 expression was increased in a population of Mφs and corresponded in intensity, colocalization and percentage with that of MAgs on the same cells, while Bax expression was reduced. In lymphocyte aggregates, Bcl‐2 and Bax did not show any differences. We conclude that overexpression of Bcl‐2 in Mφs containing MTB may be associated with intracellular survival of the bacilli, thus demonstrating one way by which MTB can escape the host's cellular response and killing.
Immunization with Peptides from 60 kDa Ro in Diverse Mouse Strains
Authors: Scofield R. H. , Pierce P. G. , James J. A. , Kaufman K. M. , Kurien B. T.
Published: March 2003

Antibodies binding the Ro (or SSA) and La (or SBB) proteins are commonly found in a high proportion of sera from patients with systemic lupus erythematosus or Sjögren's syndrome. The mechanism by which these autoantibodies arise is not known. Others and we have shown that immunization of nonautoimmune‐prone mice with short peptides from the Ro ribonucleoprotein particle can induce autoimmunity to 60 kDa Ro and 52 kDa Ro as well as to the 48 kDa La protein after epitope spreading. We have explored the differences in the epitope spreading after 60 kDa Ro peptide immunization in several strains of mice. There is intra‐ and intermolecular diversification of the immune response after immunization of DBA/2J animals with a monomer peptide representing the residues 480–494 of the 60 kDa Ro protein, but this peptide does not induce epitope spreading when used as the immunogen in either C57Bl/6J or PL/J mice. Similar to previously studied BALB/c mice, DBA/2J mice have antibodies binding many epitopes of 60 kDa Ro, and some sera bind 52 kDa Ro as well as La. These mice have antinuclear antibody in their sera. These data demonstrate that Ro peptide immunization results in different outcomes depending upon the strain of mouse used. Furthermore, these data suggest that genetic variation is important with regard to responding towards short peptide immunization by epitope spreading.
Analysis of Gene Expression During Maturation of Immature Dendritic Cells Derived from Peripheral Blood Monocytes
Authors: Matsunaga T. , Ishida T. , Takekawa M. , Nishimura S. , Adachi M. , Imai K.
Published: March 2003

Dendritic cells (DCs) are the most important antigen‐presenting cells. Many recent studies have compared the function of immature DCs (iDCs) and mature DCs (mDCs), but there have been few reports of the molecular changes that occur in DCs during maturation. Here, we report on differential gene expression in iDCs generated from peripheral blood monocytes compared with mDCs. Gene expression was evaluated using the differential display method after activation of iDCs with a low concentration of lipopolysaccharide (LPS) to induce maturation. Proteasome subunit alpha type 3 (PSMA3), transcription factor EC (TFEC) isoform and BTK region clone 2f10‐rpi were transiently upregulated. Tryptophanyl‐tRNA synthetase and CD63 antigen were upregulated for at least 24 h. Neuronal apoptosis inhibitory protein (NAIP) and transforming growth factor‐β‐induced 68 kDa protein were downregulated. This is the first report of NAIP expression in human DCs. By comparing the expression of NAIP with that of other members of the inhibitor of apoptosis protein (IAP) family and the Bcl‐2 family, only NAIP was found to be strongly expressed in iDCs before stimulation by LPS. PSMA3 was also induced in the DCs stimulated with immune complex. These findings might contribute to our understanding of DC maturation and the effectiveness of DC‐based vaccines.
Sulphate–borate relations in an evaporitic lacustrine environment: the Sultançayir Gypsum (Miocene, western Anatolia)
Authors: ORTÍ F. , HELVACİ C. , ROSELL L. , GÜNDOĞAN I.
Published: March 2003

Calcium‐borates, mainly pandermite (priceite) and howlite, but also bakerite and colemanite, are intercalated within the Sultançayir Gypsum (Miocene, Sultançayir Basin, western Anatolia). This lacustrine unit, represented by secondary gypsum in outcrop, is characterized by: (1) a clear facies distribution of depocentral laminated lithofacies and debris‐flow deposits, a wide marginal zone of sabkha deposits, and at least one selenitic shoal located toward the basin margin; (2) evaporitic cycles displaying a shallowing‐upward trend; and (3) a diagenetic evolution of primary gypsum to (burial) anhydrite followed by its final re‐hydration. The calcium borates precipitated only in the depocentre of the lake and were partly affected by synsedimentary reworking, indicating that they formed during very early diagenesis. The lithofacies, which are made up of a host gypsum (finely laminated) and borates (nodules, irregular masses and discontinuous bands; also fine laminations), indicate that the borates grew interstitially because of the inflow and mixing of borate‐rich solutions with basinal brines. Borate growth displaced and replaced primary gypsum beneath a relatively deep depositional floor. Borate formation as free precipitates was much less common. The anhydritization of primary gypsum took place during early to late diagenesis (burial <250 m deep). This process also resulted in partial replacement of pandermite and accompanying borates (bakerite and howlite) as well as other early diagenetic minerals (celestite) by anhydrite. Final exhumation resulted in the replacement of anhydrite by secondary gypsum, and in the partial transformation of pandermite and howlite into secondary calcite.
The role of endolithic cyanobacteria in the formation of lithified laminae in Bahamian stromatolites
Authors: Macintyre Ian G. , Prufert‐Bebout Leslie , Reid R. Pamela
Published: March 2003

The microboring activity of endolithic cyanobacteria plays a major role in the formation of the dominant lithified laminae in modern marine stromatolites in the Exuma Cays, Bahamas. These stromatolites are composed primarily of fine‐grained carbonate sand that is trapped and bound by the filamentous cyanobacteria Schizothrix sp.. Periodic introduction of coccoid endolithic cyanobacteria Solentia sp. during hiatuses in stromatolite growth associated with very low rates of sedimentation results in the formation of lithified horizons, 200–1000 μm thick. These layers consist of micritized grains that are welded together at point contacts. The micritization is caused by extensive microboring and carbonate precipitation within boreholes concurrent with endolithic activity. Grain welding occurs when boreholes cross from one grain to another at point contacts. Thus, microboring destroys original grain textures but, at the same time, plays a constructional role in stromatolite growth by forming lithified layers of welded grains. These lateral bands of fused carbonate grains help to stabilize and preserve the stromatolite deposits.
Silicification and dolomitization of anhydrite nodules in argillaceous terrestrial deposits: an example of meteoric‐dominated diagenesis from the Triassic of central Spain
Authors: Alonso‐Zarza A. M. , Sánchez‐Moya Y. , Bustillo M. A. , Sopeña A. , Delgado A.
Published: March 2003

Cauliflower‐shaped nodules are widespread in a single red mudstone bed in the Buntsandstein (Triassic) facies of the Iberian Range. They consist mostly of quartz, dolomite and calcite, but other minerals, such as barite, kaolinite and iron oxyhydroxides, are also present. The nodules are spherical, ovoid or elongate in shape and range from 1 to 8 cm across. The surface of the nodules is irregular, and some show a pedogenic coating of microspar. The sedimentological and petrographic data suggest that the initial anhydrite nodules formed through a progressive increase in the porewater concentration of Ca2+ and SO42– in a vadose environment, occasionally under the influence of pedogenic processes. Partial replacement of the anhydrite by megaquartz occurred under more dilute conditions in the same type of setting, as indicated by the presence of organic filaments on the quartz crystal surfaces. In type A nodules, the dissolution of the innermost anhydrite was complete, and different types of quartz cement filled the porosity. Fracturing and meteoric cementation by calcite and minor amounts of kaolinite were the latest processes affecting these nodules. In type B nodules, the dissolution of the anhydrite was incomplete, inhibiting quartz cementation and enabling later dolomitization of the anhydrite. Dolomitization appears to have been driven by sulphate reduction, as indicated by the presence of bacterial bodies within the dolomite crystals. Dedolomitization and precipitation of barite, kaolinite and calcite spar cements occurred later under the influence of meteoric solutions. The nodules may mark the former locations of the water table and provide evidence for an episode of highly evaporitic conditions throughout wide areas of the basin. Their occurrence reveals not only a complex diagenetic history but is also indicative of palaeogeographic and palaeoclimatic conditions.
Facies architecture of a submarine fan channel–levee complex: the Juniper Ridge Conglomerate, Coalinga, California
Authors: Hickson Thomas A. , Lowe Donald R.
Published: March 2003

The Upper Cretaceous Juniper Ridge Conglomerate (JRC) near Coalinga, California, provides a rare, high‐quality exposure of a submarine channel to overbank transition. The facies architecture of the JRC comprises a thick, predominantly mudstone sequence overlain by a channellized conglomerate package. Conglomeratic bounding surfaces truncate successions of interbedded turbiditic sandstones and mudstones both vertically and laterally. Thick‐bedded, massive sandstones are interbedded with conglomerates. Facies architecture, palaeocurrent indicators, slump features, sandstone percentages and sandstone bed thickness trends lead to the interpretation that these elements comprise channel and overbank facies. A vertical sequence with conglomerate at the base, followed by thick‐bedded sandstone, and capped by interbedded turbiditic sandstone and mudstone form a fining‐upward lithofacies association that is interpreted as a single channel‐fill/overbank system. Three similar lithofacies associations can be related to autocyclic processes of thalweg migration and submarine fan aggradation or to allocyclically driven changes in sediment calibre.
Systematics of Hypanartia (Lepidoptera: Nymphalidae: Nymphalinae), with a test for geographical speciation mechanisms in the Andes
Authors: Willmott Keith R. , Hall Jason P. W. , Lamas Gerardo
Published: March 2003

A taxonomic review of the Neotropical nymphaline butterfly genusHypanartiaHübner is presented, including notes on the taxonomy, biology and distribution of its component species, illustrations of all taxa and the male genitalia of all species, and the description of four new species and two new subspecies:Hypanartia celestiasp.n.,H. cinderellasp.n.,H. dione disjunctassp.n.,H. fasslisp.n.,H. trimaculatasp.n. andH. trimaculata autumnassp.n.Hypanartia arcaei(Salvin) is placed as a subspecies ofH. dione(Latreille) (stat.n.) and lectotypes are designated for eight nominal taxa. Fourteen species are recognized, with the centre of diversity being in high Andean cloud forest habitats. A cladistic analysis was conducted, based on fifty‐three illustrated characters of male genitalic and abdominal morphology, and external facies, to investigate phylogenetic relationships. The resulting phylogenetic hypothesis was used to test four different geographical mechanisms of speciation in the Andes: colonization from temperate latitudes, speciation across elevational gradients, radiation within the Andes and allopatric speciation between the Andes and other montane regions. There is evidence that speciation across an elevational gradient occurred twice, both times into elevations largely unoccupied by the genus, and in both cases followed by subsequent, elevationally sympatric,in situradiation. Differentiation in allopatry between montane regions has apparently been of recent influence only, causing infraspecific variation in two species. These results parallel several recent studies of Andean bird speciation.
Larval morphology and phylogenetic position of Micromalthus debilis LeConte (Coleoptera: Micromalthidae)
Authors: Beutel R. G. , Hörnschemeyer T.
Published: March 2003

Abstract External and internal structures of the cerambycoid and triungulin larvae of Micromalthus debilis are described and compared to features found in larvae of other groups of Coleoptera. The morphological data are evaluated with respect to the systematic position of Micromalthidae. A cladistic analysis was carried out with fifty characters. Micromalthidae are not closely related to Lymexylidae (Polyphaga: Cucujiformia) but belong to Archostemata, which is confirmed as a monophyletic unit. Micromalthidae are specialized in terms of morphology and life cycle and are characterized by a considerable number of larval autapomorphies. Their sister‐group relationship with Cupedidae is supported by several apomorphic features, which are probably correlated with xylobiontic habits: head transverse and strongly rounded laterally, absence of stemmata, shortened antennae, presence of sternal asperities and presence of eversible lobes of segment IX. Cupedidae is monophyletic and Priamca is the sister group of the remaining genera of Cupedidae included in the analysis. A closer relationship between Tenomerga and Rhipsideigma is supported by several larval synapomorphies. The ancestral life style of larvae of Archostemata was probably xylobiontic. This is suggested by derived groundplan features of the suborder, which are also found in larvae of non‐related, wood‐associated families.
Cladistic analysis and biogeography of the cicadas of the Indo‐Pacific subtribe Cosmopsaltriina (Hemiptera: Cicadoidea: Cicadidae)
Authors: Duffels J. P. , Turner H.
Published: March 2003

Abstract A consensus cladogram is presented for ninety‐seven of the ninety‐nine (sub)species of the cicada subtribe Cosmopsaltriina on the basis of a cladistic analysis of forty‐nine characters. The consensus cladogram confirms the monophyly of the eight genera constituting the subtribe, and the monophyly of the subtribe as a whole. Cosmopsaltriina occur in Sulawesi, the Moluccas, New Guinea, Cape York, the Solomon Islands, Vanuatu, Fiji, Tonga and Samoa. The subtribe demonstrates a high rate of endemism on genus, species group and species level. The taxon‐area and consensus‐area cladograms resulting from Brooks parsimony analysis are discussed in relation to the palaeogeography of the area.
Phylogenetic reassessment of the five forewing  radial‐veined tribes of Riodininae (Lepidoptera: Riodinidae)
Authors: Hall Jason P. W.
Published: March 2003

The relationships among the genera and tribal groupings of Riodininae with five forewing radial veins, and between these and tribes with four forewing radial veins, were examined using a phylogenetic analysis. Using the type species from all sixteen genera in the tribal groupings Eurybiini, Mesosemiini and incertae sedis (a presumed paraphyletic group of loosely related genera), and representatives from the four forewing radial‐veined riodinine tribes, thirty‐five new and traditional characters were coded from adult ecology, wing venation and pattern, the adult head and body, male and female genitalia, and early stage ecology and morphology. The majority of characters are illustrated. Phylogenetic analysis of these data produced five equally most parsimonious cladograms using equal weights and after successive weighting. The strict consensus of these confirms the monophyly of Eurybiini and Mesosemiini as currently conceived, but also indicates several higher‐level relationships not previously hypothesized. Mesosemiini is here more broadly defined to also include the entire incertae sedis section, and the tribe is divided into Mesosemiina, for the previously delimited Mesosemiini plus Eunogyra and Teratophthalma, and Napaeina, subtr.n. for the incertae sedis section minus these two genera. The following hypothesis of relationships is tentatively proposed for the basal clades of Riodininae: Mesosemiini + (Eurybiini + remainder of Riodininae). These new hypotheses, and the characters supporting them, are discussed and compared with those previously proposed.
A new source of isotopically heavy sulphur in lode‐gold deposits of NW Spain: a batch volatilization process in the conversion of pyrite to pyrrhotite by contact metamorphism
Authors: Arias  , Corretgé  , Villa
Published: March 2003

The conversion of pyrite to pyrrhotite is identified in this study as a new source of isotopically heavy sulphur in thermal domes. Contact metamorphism of a sequence of pyrite‐rich shales by the Penedela blind intrusion (NW Spain) causes the conversion of diagenetic pyrite to pyrrhotite at a temperature of 150 °C. This process occurred in a closed system with total consumption of the diagenetic pyrite and production of H2S‐rich fluids. The H2S liberated in this unidirectional reaction shows a relatively heavy δ34S, in agreement with a batch volatilization process. The mixture of this H2S‐rich fluids with derived sulphur from Lower Cambrian carbonates produced gold‐bearing pyrite at a temperature of 340 °C. The contribution from these two different sulphur sources was 86% and 14%, respectively. The metamorphic fluids migrated through permeable zones such as fractures and shear zones, producing a lode‐gold deposit.
Extinct spreading on the Cocos Ridge
Authors: Meschede M. , Barckhausen U. , Worm H.‐U.
Published: March 2003

Using recently acquired marine magnetic data and existing magnetic and bathymetric data sets together with ODP Leg 170 age determinations we present a revised plate tectonic model for the southern Cocos and northern Nazca plate area. According to this model the formation of the southern Cocos plate was governed by spreading at different ridge axes with alternations between spreading ridges producing a complex magnetic anomaly pattern. In the Cocos and Malpelo ridge area we have identified two precursors of the recently active Cocos–Nacza spreading system which were active from 22.8 to 14.7 Ma, with a change in spreading direction from NW–SE to ENE–WSW at 19.5 Ma. The oceanic crust of these abandoned spreading systems was subsequently thickened and overprinted by hotspot volcanism that formed the Cocos and Malpelo ridges. The centre of this hotspot volcanism is about 500 km away from, but most probably related to, the Galapagos hotspot.
Drainage diversions as evidence of propagating active faults: example of the El Asnam and Thenia faults, Algeria
Authors: Boudiaf  , Ritz  , Philip
Published: March 2003

Digital elevation models and aerial photographs provide evidence of past drainage diversions associated with known and inferred active faults in Northern Algeria. The El Asnam anticline is a fault‐bend fold that is growing in response to displacement on the historically active El Asnam fault. The diversion of the Fodda River and a sequence of uplifted palaeovalleys across the anticline formed in response to the active southwestward propagation of the Sidi Ada–El Ardja segment of the El Asnam anticline. Deformation associated with the 1980 El Asnam earthquake (Ms 7.3) and its effect on drainage demonstrate the occurrence of coseismic uplift of the El Asnam anticline associated with slip on the underlying thrust fault. Similar geomorphic relations are observed between the Isser River and the Thenia fault. Diversions of the Isser River and evidence for Quaternary uplift indicate that the Thenia fault, which is close to Algiers, is tectonically active and should be considered to be a source of potentially damaging earthquakes.
Elemental mobility during the weathering of exposed lower crust: the kinzigitic paragneisses from the Serre, Calabria, southern Italy
Authors: Mongelli G. , Cullers R.L. , Dinelli E. , Rottura A.
Published: March 2003

Weathering and transportation studies of the chemical composition of sediments have determined how surface fractionation processes modify the elemental signature due to provenance and tectonic setting of siliciclastic rocks. Although the bulk of the exposed upper continental crust comprises granitoids, metamorphic rocks from the intermediate to lower crust may be, in some geological contexts, the provenance of siliciclastic sediments. A preferential enrichment of the LREE relative to the HREE is observed in weathered, garnet‐rich, kinzigitic paragneisses from the Calabrian Arc, southern Italy. This fractionation is due mostly to the mineralogical control exerted by monazite, which is concentrated in the silt‐size fraction of the soil. However, a significant part of HREE, released during garnet alteration, is trapped by secondary minerals in the clay‐sized fraction of the soil, in a manner similar to Pb2+ and Cs+, cations of some concern in environmental geochemistry. In the weathered material monazite is also important in controlling the Eu‐anomaly, the negative size of which increases with increasing Th addition. The Eu‐anomaly in the clay‐sized fraction of the soil is very similar to that of the fresh rock, suggesting that the Eu/Eu* index in pelitic sediments deriving from the intermediate to lower crust may be regarded as a reliable indicator of parental affinity. Other provenance indicators include La/Th, which share the same mineralogical control; indicators of contrasting mafic and felsic provenance, e.g. Sc/Th, should be used with care.
Cyclostratigraphy and astrochronology of the Tripoli diatomite formation (pre‐evaporite Messinian, Sicily, Italy)
Authors: Hilgen  , Krijgsman
Published: March 2003

The ongoing debate about the Messinian salinity crisis in the Mediternean is fuelled in part by the lack of an adequate time control. The most accurate and, at the same time, detailed constraints are nowadays provided by the astronomical dating technique. Here we present an astronomical age model for the cyclically bedded Tripoli diatomite Formation on Sicily (pre‐evaporite Messinian, Italy) based on an integrated stratigraphic study of three key‐sections, Falconara, Gibliscemi and Capodarso. Characteristic sedimentary cycle patterns allow (i) the sections to be cyclostratigraphically correlated, the ‘bed‐to‐bed’ correlations being confirmed by high‐resolution planktonic foraminiferal biostratigraphy, and (ii) the Tripoli cycles to be calibrated to the astronomical record. Despite minor misfits the correctness of the tuning is evident from the match between precession‐obliquity interference in the astronomical target and its reflection in the sedimentary cycle record. The tuning provides absolute astronomical ages for all sedimentary cycles and planktonic foraminiferal events. The base of the Tripoli is astronomically dated at 7.005 Ma, indicating that the onset of diatomite formation is diachronous in the Mediternean since it started 300 000 years earlier on Sicily than on Gavdos, south of Crete. The top of the Tripoli, and thus the onset of the salinity crisis proper on Sicily, arrives at 5.98 Ma.
Origin of salinity of deep groundwater in crystalline rocks
Authors: Stober  , Bucher
Published: March 2003

Deep groundwater in fractured crystalline basement has been reported from deep mines and from scientific deep wells. Highly saline brines have been described from several km depth in the continental basement of the Canadian, Fennoscandian and Ukrainian shields and elsewhere in the world. The origin of salinity is unknown and many different possibilities have been presented. We compare the compositional evolution of deep waters in the Black Forest basement, SW Germany, with those of other deep crystalline waters, and use halogen systematics (e.g. Cl/Br ratios) and other parameters of the waters to deduce the origin of their salinity. In the Black Forest the composition of deep thermal waters results from chemical interaction of surface water with the rock matrix (mainly weathering of plagioclase and mica) and from mixing of the reacted water with stagnant saline deep water. Here we show by Na/TDS‐and Cl/TDS‐investigations, by molality‐ratios of the Na and Cl concentrations, and by Cl/Br systematics that these deep saline waters have a marine origin. The Cl/Br ratios in deep crystalline waters are very close to normal marine ratios (Cl/Br = 288 ppm basis). In contrast, Cl/Br ratios of other possible sources of salinity show distinctly different Cl/Br ratios: water derived from dissolved Tertiary halite deposits of the rift valley is in the order of Cl/Br = 2400 and water from dissolved Muschelkalk halite deposits has values of about Cl/Br = 9900. Leaching experiments on crystalline rocks, on the other hand, show that the average Cl/Br ratio of crystalline rocks is far below Cl/Br = 100.
Over how much time should the geomagnetic field be averaged to obtain the mean‐palaeomagnetic field?
Authors: Carlut  , Courtillot  , Hulot
Published: March 2003

Average geomagnetic field models are now available over six orders of magnitude in time. Models based on Present and historical, archaeomagnetic and palaeomagnetic data illustrate how the amplitudes of secular variation of nonaxial dipole terms strongly decrease as a function of averaging window, mostly when jumping from the 1‐yr to the 1700‐yr average. The mean archaeomagnetic field bridges the gap between the complex historical field and the far simpler palaeomagnetic field, and appears to be much closer to the latter. Confidences in average field coefficients based on statistical field models give a quantitative basis to the practice of averaging data over a few millenia in order to ‘suppress secular variation’. In particular, the axial quadrupole emerges from noise when the available time series exceed about 6 kyr. This happens to be close to the timescales of excursions and reversals. It is now a priority to obtain detailed data spanning the last 50 kyr.
Structural and geochemical data on the Rio Magno Unit: evidence for a new ‘Apenninic’ ophiolitic unit in Alpine Corsica and its geodynamic implications
Authors: Padoa Elisa , Saccani Emilio , Durand‐Delga Michel
Published: March 2003

The Rio Magno Unit (RMU) tectonically overlies the Schistes Lustrés units in south‐eastern Alpine Corsica. It is represented by an ophiolitic sequence, showing remarkable differences with respect to the commonly recognized Corsican ophiolites. This unit can be distinguished from the Schistes Lustrés by the lack of HP–LT metamorphism, reflecting its different geodynamic setting, although both were involved early in the same tectonic events. Similarly, the RMU can be distinguished from the Balagne Unit by the presence of normal‐MORB basalts and the scarcity of continent‐derived sedimentary input, testifying to a different oceanic palaeogeographical setting. Moreover, the petrochemical and stratigraphic features of the RMU ophiolitic sequence show close analogies with the Internal Ligurides of the Northern Apennines. The RMU represents the first record of a nonmetamorphic ‘Apenninic’‐type ophiolitic unit in Alpine Corsica, supporting the hypothesis that the Alpine Corsica – Northern Apennine system represents a double‐vergent accretionary wedge.
Why is stromatactis so rare in Mesozoic carbonate mud mounds?
Authors: Neuweiler Fritz , Bourque Pierre‐André , Boulvain Frédéric
Published: March 2003

The sedimentary–diagenetic structure stromatactis is widespread in Palaeozoic spiculitic carbonate mud mounds, but occurs only sporadically in Mesozoic sponge carbonate mud mounds. Comparative analysis of Palaeozoic and Mesozoic stromatactis limestones suggests that this variation results from the degree of siliceous sponge skeletal rigidity and the amount of internal sediment accumulation in the original cavity network. Partial to entire filling by internal sediment resulted in a continuum, from a small amount of internal sediment and large amount of cement (stromatactis, common in the Palaeozoic), to only internal sediments (aborted stromatactis, common in the Mesozoic). These observations match independent lines of evidence concerning the siliceous sponge evolution and sediment recycling (e.g. bioerosion) across the Palaeozoic to Mesozoic biotic revolution.
The Messinian Guadalhorce corridor: the last northern, Atlantic–Mediterranean gateway
Authors: Martín José M. , Braga Juan C. , Betzler Christian
Published: March 2003

Messinian marine deposits of the Guadalhorce River valley in southern Spain record evidence of the last northern gateway that existed between the Mediterranean and the Atlantic. They comprise sandstones and conglomerates with unidirectional cross‐bed sets up to nearly 1 km long in their down‐sedimentary‐dip direction. These cross‐bed sets relate to extremely fast (1.0–1.5 m s−1) bottom currents flowing from the Mediterranean into the Atlantic. The Guadalhorce gateway (which had a maximum width of 5 km and a maximum water depth of 120 m) was an important element controlling the Messinian pre‐evaporitic oceanic circulation in the Mediterranean Sea, as it acted as a major outflow channel. Its closure limited the exchange of water between the Atlantic and the Mediterranean to the Rifian corridors of Morocco, inducing water‐mass restriction and stratification in the western Mediterranean immediately prior to the `Messinian Salinity Crisis'.
Strath terraces of Jinshaan Canyon, Yellow River, and Quaternary tectonic movements of the Ordos Plateau, North China
Authors: Cheng Shaoping , Deng Qidong , Zhou Shiwei , Yang Guizhi
Published: March 2003

ABSTRACT Studies of the strath terraces in Jinshaan Canyon − where the Yellow River cuts through the Ordos Plateau in the continental interior of China − provide an opportunity to solve some of the critical problems associated with Quaternary tectonic movement of the plateau. Six strath terraces indicate that five episodes of regional epeirogenic uplift affected the Ordos Plateau during the Quaternary. The local tectonic deformation is superimposed on the regional epeirogenic uplift, expressed either as faulting or as non‐uniform uplift induced by local arching. The results have important implications for understanding the relationship between the regional epeirogenic uplift of the Ordos Plateau and the uplift of the Qingzang Plateau, time lines of climate change in the regional epeirogenic uplift landscape, and the genesis of strath terraces associated with the through‐flowing plateau drainage in the continental interior.
Palaeozoic late collisional strike‐slip deformations in Tianshan and Altay, Eastern Xinjiang, NW China
Authors: Laurent‐Charvet Sébastien , Charvet Jacques , Shu Liangshu , Ma Ruishi , Lu Huafu
Published: March 2003

ABSTRACT In Central Asia, thrusts and shear zones resulting from Palaeozoic accretional events were reworked by E–W‐trending ductile strike‐slip faults during late Palaeozoic–early Mesozoic time. In the Tianshan range, microstructures and quartz C‐axis fabrics show a main dextral shearing associated with sinistral localized shear zones. The relationship between these conjugate structures indicates a NNW–SSE‐trending bulk shortening. In the Chinese Altay mountains, the existence of δ‐type microstructures in an important sinistral mylonitic zone infers high rates of deformation. This shear zone is bordered by a late dextral ductile fault synchronous with a granite emplacement. Field evidence and datings from the literature provide chronological constraints. In the late Carboniferous, the sinistral mylonitic deformation took place in the Erqishi–Irtysh shear zone in the northeastern part of Xinjiang and in Kazakhstan. During the Early Permian, a regional dextral event occurred in the Tianshan range and under the whole of northern Xinjiang.
Effect of lateral suppressor on petal initiation in tomato
Authors: Szymkowiak Eugene J. , Sussex Ian M.
Published: March 2003

Flowers developing on tomato (Lycopersicon esculentum) plants homozygous for the lateral suppressor(ls) mutation lack petals. Scanning electron micrographs revealed that in ls plants no second whorl organs were initiated. The initiation of first, third, and fourth whorl organs were unaffected by this mutation. To investigate interactions between the cells in different layers of the floral meristem during organ initiation, a periclinal chimera between wild‐type and ls tomato was generated. Flowers of the chimera having ls cells in the outer meristem layer (L1) and wild‐type cells in internal layers (L2 and L3) developed normally, including the initiation of organ primordia that differentiated as petals in normal positions within the second whorl. L1 of the chimera developed in a non‐autonomous manner during petal development. Thus, wild‐type cells occupying the internal meristem layers provided developmental cues necessary for initiation of petal primordia at appropriate positions on the floral meristem. L1 cells carrying the lateral suppressor mutation were fully capable of responding to this information and differentiated appropriately.