Controls on migration of conodont fauna in peripheral oceanic areas. An example from the Middle Triassic of the Northern Peri-Tethys

Middle Triassic conodont assemblages in the semi-closed Peri-Tethyan Germanic Basin comprise endemic forms, which evolved within the basin, and immigrants from the Tethys Ocean. Migration from the Tethys proceeded diachronously through three tectonically predisposed pathways (gates) and was controlled by relative sealevel changes recorded in depositional sequences of the Muschelkalk. In the Early and Middle Anisian predominant were the forms that originated in the Eastern Tethys and in southern basins of the Western Tethys. They migrated through the East Carpathian Gate and Silesian-Moravian Gate. In the late Anisian and early Ladinian forms from the Western Tethyan basins prevailed; their migration pathway led through the Western and East Carpathian Gates. The latter gate was active only at the turn of Illyrian and Fassanian. Episodes of migration of the Tethyan forms and dispersal of conodont fauna throughout the German Basin coincide with the transgressive or highstand phases of a particular depositional sequence (as defined by Szulc, 1999). The most significant proportion of the Tethyan species appears to correlate with the maximum flooding surface of the A₃ sequence, (Lower Muschelkalk) later they decrease in diversity. In the Upper Muschelkalk the most numerous Tethyan species correspond to the transgressive phase of the L₁ sequence. Above the mfs of the L₁ sequence only the Germanic forms remain.     

On the Procompsognathus postcranium (Late Triassic, Germany)

A review of the historical background of the material housed in the Staatliches Museum für Naturkunde (Stuttgart) and ascribed to Procompsognathus triassicus (Upper Triassic, Germany) is provided. The systematic position of the postcranial remains is discussed. The combined results of cladistic analyses suggest that the type material, an incomplete postcranial skeleton in two pieces (SMNS 12591), is from a theropod close to Segisaurus and Coelophysis. An isolated manus (SMNS 12352a) is definitely not theropodan, but could be from any small basal archosaur. The remarkable diversity of the carnivorous guild that dwelled in southern Germany before the end-Triassic events is underlined.     

Astronomical orientation and learning in the earwig Labidura riparia

Astronomical orientation experiments have been carried out on adults and young of the earwig Labidura riparia. In the water, the earwigs

1.

(1) assumed a correct landward orientation, concordant with their home shore;     

Differential thermal tolerance and energetic trajectories during ontogeny in porcelain crabs,genus Petrolisthes

Thermal tolerance limits of marine intertidal zone organisms are elevated compared to subtidal species, but are typically just slightly higher than maximal habitat temperatures. The small thermal safety margins maintained by intertidal zone organisms suggest that high thermal tolerance is associated with a physiological cost. If true, we hypothesize that species that transition between intertidal zone and planktonic habitats during ontogeny, will adjust their thermal tolerance accordingly to capitalize upon potential energy savings while in a thermally benign habitat. We tested this hypothesis in porcelain crabs that transition between the thermally stressful, intertidal zone as embryos, to the thermally benign pelagic zone as larvae, and back at settlement. We found the more thermally tolerant, mid-intertidal zone species, Petrolisthes cinctipes, and the less thermally tolerant, subtidal zone species, Petrolisthes manimacilis, exhibited reduced thermal tolerance (LT₅₀) in the transition from embryos to larvae. This was associated with an increased oxygen consumption rate in both species, though P. cinctipes exhibited a significantly greater increase in oxygen consumption. P. cinctipes also showed an increase in thermal tolerance in settled juveniles compared to pelagic zoea I larvae, resulting in an overall V-shaped thermal tolerance relationship during ontogeny, while in P. manimaculis thermal tolerance was significantly lower in juveniles compared to zoea I. In neither species were these changes (zoea I to juvenile) associated with a significant change in metabolism. While embryos and juveniles of P. cinctipes have thermal tolerance limits near intertidal habitat thermal maxima (∼32.5 °C), all three life-history stages in P. manimaculis (especially embryos and larvae) exhibit considerable thermal safety margins. The mechanisms underlying this “excess” thermal tolerance in P. manimacilis embryos are unknown, but suggest that patterns of thermal tolerance in early life history stages are species-specific.     

hMLH1、P27、P53的表达及其在宫颈癌发病中的意义

目的 了解宫颈癌中hMLH1、P27、P53表达情况及其与宫颈癌发生和发展的关系.方法 采用免疫组织化学技术SP法检测临床资料较完整的72例子宫颈鳞癌和31例慢性宫颈炎组织hMLH1、P27、P53蛋白表达.结果 （1）hMLH1在宫颈炎及宫颈癌组的表达率分别为61.3%和58.3%,差异无显著性（P＞0.05）;hM-LH1在宫颈癌各期中表达率分别为Ⅰ期60.0%,Ⅱ期52.6%,Ⅲ期33.3%,差异无显著性（P＞0.05）;hMLH1表达率与宫颈癌分级无关（P＞0.05）;（2）P27在宫颈炎及宫颈癌组的表达率分别为74.2%%和76.4%,差异无显著性（P＞0.05）;P27的表达率与宫颈癌分级和分期无关（P＞0.05）;（3）P53在宫颈炎及宫颈癌组的表达率分别为32.3%和65.3%,差异有显著性（P＜0.05）;P53在宫颈癌各级中的表达率分别为Ⅰ级36.4%,Ⅱ级73.0%,Ⅲ级67.9%,Ⅰ级与Ⅱ、Ⅲ级的表达率差异有显著性（P＜0.05）;P53表达率与宫颈癌分期无关（P＜0.05）;（4）hMLH1表达阳性与阴性的宫颈癌中P27的表达率为94.6%和60.0%,差异有显著性（P＜0.05）;P53的表达率为62.8%和62.1%,差异无显著性（P＞0.05）.结论 P53基因突变与宫颈癌的发生和组织分化程度有关;hMLH1与P27表达缺失和宫颈癌发生的关系尚不确切.hMLH1可能使宫颈癌中P27表达上调,而对p53基因突变累积无明显抑制作用.     

Distribution of GSTM1, GSTT1, GSTP1 and TP53 disease-associated gene variants in native and urban Venezuelan populations

The contemporary Venezuelan population is the product of major admixture process across various historical events, which has provided it a particular genetic background. The aim of this study concerns the analysis of glutathione S-transferase (GST) GSTM1, GSTP1 and GSTT1 genetic variants and five polymorphisms at the TP53 gene, which are related to cancer susceptibility, in an urban/admixed population and five Amerindian tribes (Bari, Panare, Pemon, Warao and Wayuu) from Venezuela. Genotyping was carried out in 120 individuals from an urban sample and 188 Amerindians. The analysis performed on TP53 haplotype and GST allele distribution showed a close correlation for Pemon and Warao populations, while Bari group appears isolated from the other populations. GSTT1 null variant frequency in our admixed (11%) and native samples (0.0–11.4%) was lower when compared with Caucasians, Africans and Asians. Frequency of the GSTP1*Val cancer-associated allele found in Bari (88.6%) and Panare (63.0%) is of the highest so far reported. Fourteen TP53 haplotypes were observed in the admixed populations, whereas only 3 to 5 in Amerindians. To our knowledge this is the first report of GST polymorphisms and TP53 haplotype distribution in Venezuelans. The distribution of most of analyzed polymorphisms in the urban sample is consistent with the admixed origin of the present-day population of Venezuela. While, the inter-ethnic variations in genetic polymorphisms found in Native American tribes seem to be the result of the influence of demographic factors. These results provide additional data for undertaking ethnographic and disease association studies in Venezuela.     

The ontogeny of feeding behavior and cranial morphology in the leopard shark Triakis semifasciata (Girard 1854): A longitudinal perspective

While much is known about the ecological and functional morphology of feeding in lower vertebrates, studies of elasmobranch feeding over ontogeny are broadly lacking. In this study, the ontogeny of feeding behavior and morphology were investigated in neonatal and young-of-the-year leopard sharks Triakis semifasciata using morphometric measurements of growth and high-speed videography in a longitudinal study. Five food types were used during filming sessions to facilitate differentiation of modulation and variation over ontogeny. Functional aspects of muscle and buccal volume scaling were investigated through dissection. Growth over ontogeny was shown to influence numerous kinematic variables, while intra- and inter-individual variability was the dominant factor affecting feeding behavior. Modulation of feeding behavior based on food size and elusiveness was present for timing variables and predator motion during the strike, but not for food motion or the relative extent of buccal expansion. Allometric growth occurred in all aspects of external cranial morphology measured, resulting in a shallower head profile, anterior displacement of the mouth, and relatively larger jaw musculature over ontogeny. While the degree to which morphology constrains or enhances behavior cannot be directly quantified, variability in behavior greatly exceeds variability in morphology over early ontogeny. Maintenance of a behaviorally and morphologically versatile feeding apparatus throughout ontogeny is proposed to enhance the exploitation of resources and facilitate a diverse diet in T. semifasciata under variable environmental conditions.     

Chronological expression of Wnt target genes Ccnd1, Myc, Cdkn1a, Tfrc, Plf1 and Ramp3

The canonical Wnt pathway regulates several biological processes including development, cell growth and proliferation via consecutive gene regulation. A high number of target genes of the Wnt pathway has been identified, but the chronological order of target gene expression is still elusive. This order is supposed to be crucial for the controlled course of events downstream of the activated Wnt pathway. Here we present the expression chronologies of the target genes Ccnd1 (encoding for cyclin D1), Myc (c-Myc), Cdkn1a (p21^CIP1/WAF1), Tfrc (Transferrin receptor 1), Plf1 (Proliferin-1) and Ramp3 (Receptor activity-modifying protein 3) in C57MG cells after stimulation with Wnt-3a. We discriminated between immediate (below 1 h), early (between 1 and 6 h), intermediate (between 6 and 12 h) and late (after 12 h) targets. According to this classification Myc and Tfrc belong to the immediate target genes; Ccnd1, Plf1 and Ramp3 are early target genes and Cdkn1a is an intermediate target gene.     

胃癌中P16、nm23-h1、P53表达及其与患者预后的关系

目的:探讨胃癌组织中P16,nm23-h1和P53表达情况及其与患者预后的关系。方法:应用免疫组化SABC法检测91例手术切除胃癌组织中P16,nm 23-h1和P53表达。结果:胃癌中P16,nm23-h1和P53表达阳性率分别33．0%(30/91),38．5%(35/91), 53．8%(49/91)。p16,nm23-h 1和P53在胃癌中表达与淋巴结有无转移,不同的浸润深度,TNM分期,不同组织学类型均有显著差异(P＜0．05)。而它们与肿瘤患者年龄,性别差异无统计学意义(P＞0．05)。等级相关分析结果显示P16与P53表达呈负相关(P＜0．05),P16与nm23-h1表达呈正相关(P＜0．05),P53与nm23-h1表达呈负相关(P＜0．05)。生存曲线研究结果显示P16,nm23-h1和P53表达与患者术后生存时间显著相关(P＜0．05)。结论:P16和nm23-h1在胃癌组织中低表达及P53高表达能客观反映胃癌组织分化程度,侵袭转移能力,且其与患者预后密切相关。故检测三种指标可作为正确判断胃癌患者预后,在指导临床治疗方面有一定价值。     

Scinderella scopuliformis nov. gen., nov. sp. (Dasycladales, green algae) from the middle Triassic of Croatia

Scinderella scopuliformis nov. gen., nov. sp. is identified in the Anisian (Middle Triassic) reef limestones from the Belski dol quarry (Ivanš?ica Mt., NW Croatia). The new alga is characterised by claviform thallus, curved in the basal part, and very narrow central cavity. Thallus is often disintegrated into fragments. Laterals swell from a thin basal part, and have uniform (rarely slightly increasing) diameter along most of their length. Distally, they are flattened and probably touch each other, forming an irregular cortex. Laterals are arranged densely in close whorls and oblique to the longitudinal axis. Euspondyl arrangement is readily visible in the proximal part of the laterals, but distally, the arrangement seems more or less irregular, i.e. ruffled (Lat. scindere = ruffle, dishevel) and resembling a broom (Lat. scopulae = small broom; forma = form, shape).     

Roles for N-glycosylation in the dynamics of Edg-1/S1P1 in sphingosine 1-phosphate-stimulated cells

Sphingosine 1-phosphate (Sph-1-P) is a bioactive lipid mediator released from activated platelets. To date, 5 seven-transmembrane-spanning receptors, Edg-1/S1P1, Edg-3/S1P3, Edg-5/S1P2, Edg-6/S1P4 and Edg-8/S1P5, have been identified as specific Sph-1-P receptors. Our recent novel studies established that Edg-1/S1P1 is glycosylated in its N-terminal extracellular portion and further identified the specific glycosylation site as asparagine 30. We also demonstrated that the structure of the N-terminal ectodomain of Edg-1/S1P1 affects both its transport to the cell surface and the N-glycosylation process. These studies revealed a possible regulatory role for the N-glycan on Edg-1/S1P1 in the dynamics of the receptor, such as its lateral and internal movements within the membrane, in ligand-stimulated mammalian cells. Published in 2004.     

The reefal margin and slope of a Middle Triassic carbonate platform: the Latemar (Dolomites, Italy)

The Latemar is a mainly aggrading platform, but shows repeated backstepping during its entire development. The behaviour of the slope does not reflect accommodation changes and lateral consistencies of the lagoonal interior; the Latemar contemporaneously reveals different, even contrasting depositional characteristics. The slope of the late stage platform evolution corresponds at least partially to the base-of-slope apron model. Controlling factors on slope evolution are of tectonic (proximity of the Stava Line) and autocyclic (repeated oversteepening) nature. Other factors are insignificant and/or overprinted. The reef-facies at Latemar reveals a complex facies pattern; it varies along and across the margin and is rich in encrusting sponges, corals, biogenic crusts and Microproblematica. Some biota or fossil assemblages—e.g. foraminifers (Abriolina mediterranea, Turriglomina scandonei) or Tubiphytes multisiphonatus thrombolites—have not been described in the Dolomites before. Biostratigraphic evidence from the uppermost reef-facies confirms a mainly Anisian age of the outcropping platform interior.     

Structure and development of the style base in Abildgaardia, Bulbostylis, and Fimbristylis (Cyperaceae,Cyperoideae, Abildgaardieae)

The Abildgaardieae tribe within the family Cyperaceae comprises six or seven genera, among which Abildgaardia, Bulbostylis and Fimbristylis pose a challenge regarding their morphological delimitation. Molecular phylogenetic analyses including species of Abildgaardieae are rare, but in most of those studies, Abildgaardia and Fimbristylis appear as more closely related to each other than to the Bulbostylis genus. Duration of the style base has been one of the most widely used characters for delimiting these three genera. The style base is a persistent structure in most species of Bulbostylis and deciduous in Abildgaardia and Fimbristylis. The reasons why the style base may persist or fall off have been scarcely discussed. The assumption that abscission layers are present in the style base of all three genera and the fact that tracheids have been observed in the style base of Bulbostylis suggest that this structure might have histological complexity. In view of this, a complete ontogenetic and anatomical study of the gynoecium has been carried out for all these three genera. It turned out that the style base is histologically simple in Abildgaardia, Bulbostylis and Fimbristylis and shows similar structure and development in all three genera. The fact that the style base has a shorter duration in Abildgaardia and Fimbristylis than in Bulbostylis might be related to the lower number of sclerotised cells that make up such structures in the mature fruit of the former two genera. Abscission of the style and style base may be the result of much simpler reasons than the differentiation of an abscission layer, resulting merely from mechanical shear force effects. Differences among genera have been observed in the shape of the style base and the development of the style. The histological simplicity of the style base is consistent with the homoplastic appearance of this structure in genera that are not closely related (e.g. Rhynchospora). Because of this, while the presence of the thickened style base seems to be a synapomorphy in species of Abildgaardieae, its persistence on or detachment from the fruit might have emerged repeatedly during this clade evolution and might not be a suitable character for genera delimitation.     

Translational repression by the oocyte-specific protein P100 in Xenopus

The translational regulation of maternal mRNAs is one of the most important steps in the control of temporal-spatial gene expression during oocyte maturation and early embryogenesis in various species. Recently, it has become clear that protein components of mRNPs play essential roles in the translational regulation of maternal mRNAs. In the present study, we investigated the function of P100 in Xenopus oocytes. P100 exhibits sequence conservation with budding yeast Pat1 and is likely the orthologue of human Pat1a (also called PatL2). P100 is maternally expressed in immature oocytes, but disappears during oocyte maturation. In oocytes, P100 is an RNA binding component of ribosome-free mRNPs, associating with other mRNP components such as Xp54, xRAP55 and CPEB. Translational repression by overexpression of P100 occurred when reporter mRNAs were injected into oocytes. Intriguingly, we found that when P100 was overexpressed in the oocytes, the kinetics of oocyte maturation was considerably retarded. In addition, overexpression of P100 in oocytes significantly affected the accumulation of c-Mos and cyclin B1 during oocyte maturation. These results suggest that P100 plays a role in regulating the translation of specific maternal mRNAs required for the progression of Xenopus oocyte maturation.     

Activation of P27kip1-cyclin D1/E-CDK2 pathway by polysaccharide from Phellinus linteus leads to S-phase arrest in HT-29 cells

Our previous study showed that polysaccharide (P1) from Phellinus linteus exhibits a significant inhibitive activity on human colorectal carcinoma cells (HT-29). However its novel molecular mechanism remains unknown. To obtain insights into P1’s mechanism of action, we examined its effects on cell proliferation in vitro and in vivo, cell cycle distribution, apoptosis, autophagy, and expression of several cell cycle interrelated proteins in HT-29 cells. Interestingly, we found that volume and weight of the solid tumor significantly decreased in P1 (200 mg/kg)-treated mice compared with the control. However, slightly increased the body weight of the P1 treated tumor-bearing mice, with no significant increased ALT, AST levels in serum and LPO concentration in liver and kidney indicated that P1 has no toxicity to mammals at a dose of 200 mg/kg. Furthermore, P1 caused a significantly dose-dependent increase in the S-phase cell cycle, but no apoptosis and autophagy in HT-29 cells. RT-PCR and Western blot results showed significantly down-regulated expressions of cyclin D1, cyclin E, and CDK2, as well as increased expressions of P27kip1 in P1 (100 μg/mL)-treated HT-29 cells. These results suggested that the activation of P27kip1-cyclin D1/E-CDK2 pathway is involved in P1-induced S-phase cell cycle arrest in HT-29 cells.     

Functional differences in the cytochrome P450 1 family enzymes from Zebrafish (Danio rerio) using heterologously expressed proteins

Mammalian cytochrome P450 1 (CYP1) genes are well characterized, but in other vertebrates only the functions of CYP1A genes have been well studied. We determined the catalytic activity of zebrafish CYP1A, CYP1B1, CYP1C1, CYP1C2, and CYP1D1 proteins using 11 fluorometric substrates and benzo[a]pyrene (BaP). The resorufin-based substrates, 7-ethoxyresorufin, 7-methoxyresorufin, and 7-benzyloxyresorufin, were well metabolized by all CYP1s except CYP1D1. CYP1A metabolized nearly all substrates tested, although rates for non-resorufin substrates were typically lower than resorufin-based substrates. Zebrafish CYP1s did not metabolize 7-benzyloxyquinoline, 3-[2-(N,N-diethyl-N-methylamino)ethyl]-7-methoxy-4-methylcoumarin or 7-methoxy-4-(aminomethyl)-coumarin. CYP1B1 and CYP1C2 had the highest rates of BaP metabolism. 3-Hydroxy-BaP was a prominent metabolite for all but CYP1D1. CYP1A showed broad specificity and had the highest metabolic rates for nearly all substrates. CYP1C1 and CYP1C2 had similar substrate specificity. CYP1D1 had very low activities for all substrates except BaP, and a different regioselectivity for BaP, suggesting that CYP1D1 function may be different from other CYP1s.     

Autumn migratory orientation and displacement responses of two willow warbler subspecies (Phylloscopus trochilus trochilus and P. t. acredula) in South Sweden

Topography and historical range expansion has formed a so-called migratory divide between two subspecies of willow warbler (Phylloscopus trochilus) in central Scandinavia. The autumn migratory directions of individuals assigned molecularly to both subspecies and possible hybrids were recorded using orientation cage experiments in southwest and southeast Sweden. We found pronounced differences in willow warblers’ orientation in respect to genotype. The mean directions registered in the control experiments were in accordance with the ringing recoveries and analyses of stable isotopes for Scandinavian willow warblers. With the same individuals we performed displacement experiments between both sites. They resulted in non-significant orientation, which could be explained by the intermediate distance of the displacement or reactions to housing, transportation and location. On a separate set of birds we tested whether stress following transportation could explain the disorientation and found that orientation before and after transport was unchanged. Experimental studies of effects of intermediate displacements across longitudes and studies of orientation of hybrid individuals in the zones of migratory divides are crucial for understanding the mechanisms underlying orientation behaviour. Our work further stresses the importance of knowing the migration genotype of a particular bird under study, in order to correctly evaluate expected migration routes.