The in Vitro Effect of Metyrapone on Steroid Synthesis in Mice Adrenals at Different Circadian Stages

The circadian rhythm of the in vitro biosynthesis of Cortisol and cortisone in mice adrenals has been documented in the absence and presence of 0.1 μmol metyrapone, an inhibitor of steroid 11β-monooxygenase. After 3 weeks of synchronization with 12 h light: 12 h darkness, adrenalectomy was performed at eight circadian stages: 0, 4, 9, 10, 13, 16, 21, and 22 h after light onset (HALO). Because it has been shown that mice adrenals could convert exogenous 11 -deoxy-cortisol, the synthesis of 11-oxysteroids (Cortisol + cortisone) in adrenal homoge-nates was studied from tritiated precursor. The pattern of steroid synthesis showed a maximum around the end (10 HALO) and a minimum at the beginning of the resting period (0 HALO); the variation was ∼ 10%. A similar pattern was observed in the presence of a ∼50% inhibiting dose of metyrapone. On the other hand, the percent inhibition of 11-oxysteroids synthesis was greater at the beginning of the resting period (0 HALO) and minimum around the end of the activity span (21 HALO), with an overall variation of 20%. However, the variations were statistically insignificant (unpaired t test).     

Quantitative Detection of Epstein-Barr Virus DNA in Cerebrospinal Fluid and Blood Samples of Patients with Relapsing-Remitting Multiple Sclerosis

The presence of Epstein-Barr Virus (EBV) DNA in cerebrospinal fluid (CSF) and peripheral blood (PB) samples collected from 55 patients with clinical and radiologically-active relapsing-remitting MS (RRMS) and 51 subjects with other neurological diseases was determined using standardized commercially available kits for viral nucleic acid extraction and quantitative EBV DNA detection. Both cell-free and cell-associated CSF and PB fractions were analyzed, to distinguish latent from lytic EBV infection. EBV DNA was detected in 5.5% and 18.2% of cell-free and cell-associated CSF fractions of patients with RRMS as compared to 7.8% and 7.8% of controls; plasma and peripheral blood mononuclear cells (PBMC) positivity rates were 7.3% and 47.3% versus 5.8% and 31.4%, respectively. No significant difference in median EBV viral loads of positive samples was found between RRMS and control patients in all tested samples. Absence of statistically significant differences in EBV positivity rates between RRMS and control patients, despite the use of highly sensitive standardized methods, points to the lack of association between EBV and MS disease activity.     

A New Entodiniomorphid Ciliate,Troglocorys cava n. g., n. sp., from the Wild Eastern Chimpanzee (Pan troglodytes schweinfurthii) from Uganda

ABSTRACT. Troglocorys cava n. g., n. sp. is described from the feces of wild eastern chimpanzee, Pan troglodytes schweinfurthii, in Uganda. This new species has a spherical body with a frontal lobe, a long vestibulum, a cytoproct located at the posterior dorsal side of the body, an ovoid macronucleus, a contractile vacuole near the cytoproct, and a large concavity on the left surface of the body. Buccal ciliature is non‐retractable and consists of three ciliary zones: an adoral zone surrounding the vestibular opening, a dorso‐adoral zone extending transversely at the basis of the frontal lobe, and a vestibular zone longitudinally extending in a gently spiral curve to line the surface of the vestibulum. Two non‐retractable somatic ciliary zones comprise arches over the body surface: a short dorsal ciliary arch extending transversely at the basis of the frontal lobe and a wide C‐shaped left ciliary arch in the left concavity. Because of the presence of three ciliary zones in the non‐retractable buccal ciliature, the present genus might be a member of the family Blepharocorythidae, but the large left concavity and the C‐shaped left ciliary arch are unique, such structures have never been described from other blepharocorythids.     

Interaction of saponin and digitonin with black lipid membranes and lipid monolayers

The effects of the plant glycosides saponin as well as digitonin on the electrical conductance of black lipid membranes and the effect of these agents on the surface pressure of lipid monofilms was investigated. Both saponin and digitonin induced channel-like fluctuations in planar bilayers made either of diphytanoylphosphatidylcholine ( DPhPC ) or of DPhPC and cholesterol 2: 1 (w/w). In cholesterol-free bilayers the amount needed to induce an increase in conductance was 0.3-1 mg/ml for saponin and about 0.2 mg/ml for digitonin. In contrast, in cholesterol-containing bilayers the concentration needed to induce pores was about 10 micrograms/ml for both saponin and digitonin. In cholesterol-containing membranes the fluctuating pores induced by saponin were about 3-times more permeable to K+ than to Cl- and the macroscopic current showed an ohmic behaviour. Surface pressure experiments demonstrate that both glycosides could penetrate into lipid monofilms of pure DPhPC spread at the air/water interface with an initial surface pressure of 30 mN/m. The increase in surface pressure was considerably enhanced in cholesterol-containing films. It is assumed that the channel-like fluctuations induced by saponin as well as digitonin, in both cholesterol-free and cholesterol-rich bilayers are due to the formation of micellar structures within the lipid lattice. Probably the penetration of the glycosides into the lipid bilayer is considerably enhanced by the presence of cholesterol.     

Paeoniflorin protects cells from GalN/TNF-α-induced apoptosis via ER stress and mitochondria-dependent pathways in human L02 hepatocytes

Paeoniflorin （PF） is one of the main effective components extracted from the root of Paeonia lactiflora, which has been used clinically to treat hepatitis in traditional Chinese medicine, but the details of the underlying mechanism remain unknown. The present study was designed to investigate the mechanism of protective effect of PF on d-galactosamine （GalN） and tumor necrosis factor-α （TNF-α）-induced cell apoptosis using human L02 hepatocytes. Our results confirmed that PF could attenuate GalN/TNF-α-induced apoptotic cell death in a dose-dependent manner. The disruption of mitochondrial membrane potential and the disturbance of intracellular Ca2＋ concentration were also recovered by PF. Western blot analysis revealed that GalN/TNF-α induced the activation of a number of signature endoplasmic reticulum （ER） stress and mitochondrial markers, while PF pre-treatment had a marked dose-dependent suppression on them. Additionally, the anti-apoptotic effect of PF was further evidenced by the inhibition of caspase-3/9 activities in L02 cells. These findings suggest that PF can effectively inhibit hepatocyte apoptosis and the underlying mechanism is related to the regulating mediators in ER stress and mitochondria-dependent pathways.     

Speciation in Chitaura grasshoppers (Acrididae: Oxyinae) on the island of Sulawesi: colour patterns, morphology and contact zones

We investigate colour pattern and morphological variation in Chitaura grasshoppers on the Indonesian island of Sulawesi, and examine the relationship between divergence in these two sets of characters and population history, as reflected by variation in mitochondrial DNA. Analysis of colour pattern variation identifies a total of 21 distinct Operational Taxonomic Units in Sulawesi, the majority of which have parapatric distributions. Patterns of phenotypic variation at two contact zones in north Sulawesi suggest genetic independence between three of these colour forms, indicating that speciation has occurred. Despite this, colour pattern divergence is only coincident with morphological differentiation at one of these contact zones. In addition, neither type of phenotypic divergence is associated with geographical structuring in mitochondrial DNA, suggesting that historical isolation has had little influence on evolutionary diversification. Instead, divergence in colour pattern and morphology appears to have occurred rapidly or under conditions of continued gene flow, possibly in response to spatially variable natural selection. This result has implications for the identification of conservation units based solely on molecular markers.     

FIRST RECORD OF THE CIRRIPEDE GENUS STRAMENTUM (THORACICA, SCALPELLIFORMES) FROM THE UPPER CRETACEOUS OF JAPAN

Abstract:  The scalpelliform genus Stramentum is described from upper Turonian–Coniacian (Upper Cretaceous) strata in the Mikasa area, Hokkaido (Japan), documenting the first record of the genus from the north-west Pacific Realm. The single articulated skeleton, which is horizontally embedded in a dark grey laminated mudstone, is specifically indeterminate because capitular plates are missing. However, peduncular morphology resembles that of S. ( S .) pulchellum (Sowerby Jr), which has been described from the Cenomanian–Turonian of Europe. The present record from Japan demonstrates that this cirripede genus had a wider geographic distribution than previously assumed during the youngest phase of its radiation.     

THE CANAL SYSTEM IN SCLERITES OF LOWER CAMBRIAN SINOSACHITES (HALKIERIIDAE: SACHITIDA): SIGNIFICANCE FOR THE MOLLUSCAN AFFINITIES OF THE SACHITIDS

Abstract:  The halkieriids (Sachitida He, 1980 ) from the Early to Mid Cambrian possess a hollow sclerite with a complex branching canal system. An analysis of the canal system morphology in the halkieriid Sinosachites ( Thambetolepis ) delicatus ( Jell, 1981 ) from South Australia reveals similarities to the aesthete canal system in the shell plates of chitons, which has been analysed in a number of extant taxa. The compartments, referred to as macro-aesthetes in chitons, and lateral canals in halkieriids, have overlapping diameters and are constrained in morphology by the space of accommodation by maintaining a constant width, whereas length is more variable. Both canal systems are morphologically distinct from shell pores of other lophotrochozoans and known mollusc classes. Similarities in sclerite growth, microstructure and mineralogy further suggest that halkieriids, along with the other sachitids, are molluscs, most likely stem aculiferans (Polyplacophora and Aplacophora).     

A NEW WIDE-GAUGE SAUROPOD TRACK SITE FROM THE LATE CRETACEOUS OF MENDOZA, NEUQUÉN BASIN, ARGENTINA

Abstract:  Agua del Choique is a new Late Cretaceous sauropod track site from Mendoza Province, Neuquén Basin, Argentina. It is situated in the Loncoche Formation, late Campanian – early Maastrichthian in age, and is one of the youngest sauropod tracks site recorded in the world. Agua del Choique represents a lake setting and river-dominated delta deposits, and comprises at least 160 well-preserved tracks, located on a calcareous sandstone bed. A new ichnotaxon, Titanopodus  mendozensis ichnogen. et ichnosp. nov., is erected for the footprints of this track site. Titanopodus  mendozensis exhibits the following association of features: (1) wide-gauge trackway (manus and pes trackway ratios of 18–22 and 26–31 per cent respectively), (2) pronounced heteropody (manus-pes area ratio of 1:3), (3) outer limits of trackway defined, in some cases, by the manus tracks, and (4) manus impression with an asymmetrical crescent contour and acuminate external border. Titanopodus  mendozensis is an excellent case study of the wide-gauge style of locomotion produced by Late Cretaceous derived titanosaurs that have no impression of manual phalanges. These features, and the fossil record from the Loncoche Formation, suggest that the trackmakers were, probably, middle size saltasaurine or aeolosaurine titanosaurs (14–16 m long).