The current molecular phylogeny of Eutherian mammals challenges previous interpretations of placental evolution.

Based on histology, the placentae of eutherians are currently grouped in epitheliochorial, endotheliochorial and haemochorial placentae. In a haeckelian sense, the epitheliochorial contact with marked histiotrophic feeding by uterine milk is generally considered as primitive, especially since similar contacts exist in Marsupials. In contrast, the more intimate endotheliochorial and haemochorial contact, facilitating haemotrophic nutrition, is interpreted as a derived state.

New concise total synthesis of (+)-lentiginosine and some structural analogues.

An efficient and concise total synthesis of (+)-lentiginosine (1) starting from an L-tartaric acid-derived nitrone using organometallic addition, indium-catalyzed reduction, and ring-closing metathesis reaction as the key steps is reported. Structural analogues of (+)-1 have been also synthesized, and their inhibitory activity toward 22 commercially available glycosidases has been evaluated.

Experimental investigation of geologically produced antineutrinos with KamLAND.

The detection of electron antineutrinos produced by natural radioactivity in the Earth could yield important geophysical information. The Kamioka liquid scintillator antineutrino detector (KamLAND) has the sensitivity to detect electron antineutrinos produced by the decay of 238U and 232Th within the Earth. Earth composition models suggest that the radiogenic power from these isotope decays is 16 TW, approximately half of the total measured heat dissipation rate from the Earth.

Structure of the ovaries of the Nimba otter shrew, Micropotamogale lamottei, and the Madagascar hedgehog tenrec, Echinops telfairi.

The otter shrews are members of the subfamily Potamogalinae within the family Tenrecidae. No description of the ovaries of any member of this subfamily has been published previously. The lesser hedgehog tenrec, Echinops telfairi, is a member of the subfamily Tenrecinae of the same family and, although its ovaries have not been described, other members of this subfamily have been shown to have ovaries with non-antral follicles.

Functionalized pyrrolidines inhibit alpha-mannosidase activity and growth of human glioblastoma and melanoma cells.

New substituted pyrrolidine-3,4-diol derivatives were prepared from d-(-)- and l-(+)-phenyl glycinol. The influence of the configuration and the substitution of the lateral side chain of these derivatives on the inhibition of 25 commercial glycosidases were determined. (2R,3R,4S)-2-({[(1R)-2-Hydroxy-1-phenylethyl]amino}methyl)pyrrolidine-3,4-diol ((+)-7a) was a potent and selective inhibitor of jack bean alpha-mannosidase (K(i) = 135 nM).

Synthesis of the C(1)-C(11) polyene fragment of apoptolidin with a new sulfur dioxide-based organic chemistry.

A new sulfur dioxide-based organic chemistry has been developed as a novel approach for the stereoselective synthesis of polyene fragments based on our one-pot, four-component synthesis of polyfunctional epsilon-alkanesulfonyl-gamma,delta-unsaturated ketones. The flexibility and efficiency of this methodology are illustrated by the preparation of (+)-methyl (2E,4E,6E,8R,9S)-9-{[(tert-butyl)dimethylsilyl]oxy}-2,4,6,8-tetramethyl-11-(triethylsilyl)undeca-2,4,6-trien-10-ynoate, a synthetic intermediate of Nicolaou and co-workers, that corresponds to the C(1)-C(11) fragment of apoptolidin, which was used by the authors in their total synthesis of this promising anticancer agent.

Nature's design of nanomotors.

The need for movement is an essential concept of all living organisms. On a macroscopic scale, animals and microbes have to be able to move towards food and away from poison and predators. Plants turn their leaves toward their energy source, the sunlight.

Total asymmetric synthesis of (-)-conduramine B-1 and of its enantiomer. N-Benzyl derivatives of conduramine B-1 are beta-glucosidase inhibitors.

The 'naked sugars' (+)- and (-)-7-oxabicyclo[2.2.1]hept-5-en-2-one have been converted into (-)-conduramine B-1 ((-)-3) and its enantiomer (+)-3, respectively.

C-linked disaccharide analogue of the Thomsen-Friedenreich (T)-epitope alpha-O-conjugated to L-serine.

Condensation of a silylated beta-D-galactopyranosylaldehyde (3) with isolevoglucosenone (4) in the presence of Et(2)AlI provided bicyclic enone 5. Subsequent addition of BnNHOMe gave adduct 6, which was converted into 4-O-acetyl-1,6-anhydro-3-C-[(1 R)-1,3,4,5,7-penta-O-acetyl-2,6-anhydro-D-glycero-L-manno-heptitol-1-C-yl]-2-azido-2,3-dideoxy-beta-D-galacto-hexopyranose after liberation of the 2-amino group, its transformation into a 2-azido moiety, desilylation, and peracetylation. Ring-opening of the 1,6-anhydro galactopyranosyl unit and O-glycosidation with Fmoc-Ser-O-tBu afforded a 5:1 mixture of alpha- and beta-galactosides.

Measurement of neutrino oscillation with KamLAND: evidence of spectral distortion.

We present results of a study of neutrino oscillation based on a 766 ton/year exposure of KamLAND to reactor antineutrinos. We observe 258 nu (e) candidate events with energies above 3.4 MeV compared to 365.

Phylogeographical footprints of the Strait of Gibraltar and Quaternary climatic fluctuations in the western Mediterranean: a case study with the greater white-toothed shrew, Crocidura russula (Mammalia: Soricidae).

We used mitochondrial cyt b sequences to investigate the phylogenetic relationships of Crocidura russula (sensu lato) populations across the Strait of Gibraltar, western Europe, Maghreb, and the Mediterranean and Atlantic islands. This revealed very low genetic divergence between European and Moroccan populations. The application of a molecular clock previously calibrated for shrews suggested that the separation of European from Moroccan lineages occurred less than 60 000 bp, which is at least 5 million years (Myr) after the reopening of the Strait of Gibraltar.

Silyl methallylsulfinates: efficient and powerful agents for the chemoselective silylation of alcohols, polyols, phenols and carboxylic acids.

Alcohols, phenols and carboxylic acids are silylated with very good yields in the presence of silyl methallylsulfinates under non-basic conditions and with the formation of volatile co-products.

Sulfur dioxide-mediated syntheses of polyfunctional alkenes and (E,Z)- and (E,E)-2,4-dien-1-ones.

Efficient methods for the stereoselective synthesis of polyfunctional (E)- and (Z)-alkenes and conjugated (E,E)- and (E,Z)-dienones are presented. They rely upon one-pot, four-component processes that condense 1-oxy-1,3-dienes, silyl enol ethers, SO2, and carbon electrophiles. [structure: see text]

Rapid development of glomerular injury and renal failure in mice lacking p53R2.

The Rrm2b gene encodes p53R2, a catalytic subunit of ribonucleotide reductase that is required for DNA repair. Embryonic stem (ES) cells containing a retroviral insertion in the Rrm2b locus were used to generate mutant mice. Analysis of kidney RNA from Rrm2b (-/-) mice showed that the retroviral insertion disrupted expression of Rrm2b transcripts.

Early events in the pathogenesis of eastern equine encephalitis virus in mice.

To elucidate the pathogenesis of eastern equine encephalitis (EEE) virus infections, we used histopathology, immunohistochemistry, and in situ hybridization to track the spread and early cellular targets of viral infection in mice. Young mice were inoculated with virulent EEE virus in their right rear footpad and were followed in a time-course study for 4 days. Virulent EEE virus produced a biphasic illness characterized by an early self-limiting replication phase in peripheral tissues followed by an invariably fatal central nervous system (CNS) phase.

Neutrinoless double Beta decay and lepton flavor violation.

We point out that extensions of the standard model with low scale (approximately TeV) lepton number violation (LNV) generally lead to a pattern of lepton flavor violation (LFV) experimentally distinguishable from the one implied by models with grand unified theory scale LNV. As a consequence, muon LFV processes provide a powerful diagnostic tool to determine whether or not the effective neutrino mass can be deduced from the rate of neutrinoless double beta decay. We discuss the role of mu-->egamma and mu-->e conversion in nuclei, which will be studied with high sensitivity in forthcoming experiments.

Palladium-catalyzed desulfitative Mizoroki-Heck couplings of sulfonyl chlorides with mono- and disubstituted olefins: rhodium-catalyzed desulfitative heck-type reactions under phosphine- and base-free conditions.

New conditions have been found for the desulfitative Mizoroki-Heck arylation and trifluoromethylation of mono- and disubustituted olefins with arenesulfonyl and trifluoromethanesulfonyl chlorides. Thus (E)-1,2-disubstituted alkenes with high stereoselectivity and 1,1,2-disubstituted alkenes with 12:1 to 21:1 E/Z steroselectivity can be obtained. Herrmann's palladacycle at 0.

Expeditious asymmetric synthesis of a stereoheptad corresponding to the C(19)-C(27)-ansa chain of rifamycins: formal total synthesis of Rifamycin S.

In the presence of sulfur dioxide and an acid promoter, (-)-(1E,3Z)-2-methyl-1-((1S)-1-phenylethoxy)penta-1,3-dien-3-yl isobutyrate reacts with (Z)-3-(trimethylsilyloxy)pent-2-ene giving a silyl sulfinate intermediate that undergoes, in the presence of palladium catalyst, a desilylation and retro-ene elimination of SO(2) with formation of (-)-(1Z,2S,3R,4S)-1-ethylidene-2,4-dimethyl-5-oxo-3-((1S)-1-phenylethoxy)-heptyl isobutyrate as major product. This ethyl ketone undergoes cross-aldol reaction with (2S)-2-methyl-3-[(tert-butyldimethylsilyl)oxy]propanal giving an aldol that is reduced into a stereoheptad corresponding to the C(19)-C(27)-segment of Rifamycins with high diastereoselectivity and enantiomeric excess.

Polysulfones: solid organic catalysts for the chemoselective cleavage of methyl-substituted allyl ethers under neutral conditions.

The solid polysulfone made of SO2 and methylidenecyclopentane catalyzes the cleavage of methyl-substituted allyl ethers and liberates the corresponding alcohols.

Effects of intracerebroventricular application of brain-derived neurotrophic factor on cerebral recovery after cardiac arrest in rats.

Subject: After transient global cerebral ischemia, selective vulnerable brain areas show delayed neurodegeneration with characteristics of apoptosis. Recent data demonstrate potent neuroprotective effects of the application of endogenous growth hormones such as brain-derived neurotrophic factor (BDNF) after focal cerebral ischemia. To assess possible effects of the intracerebroventricular application of BDNF on cerebral recovery after global cerebral ischemia due to cardiac arrest in rats, various selective vulnerable brain areas were investigated.

SMART stent for salvage of hemodialysis access grafts.

Purpose: To evaluate the SMART stent for treating angioplasty-resistant hemodialysis access venous stenoses.

Materials And Methods: A retrospective study of 64 patients with polytetrafluoroethylene grafts who were treated with the SMART stent at 69 locations in the venous outflow tract was undertaken. Stents were used for elastic recoil after percutaneous transluminal angioplasty, venous rupture, or recurrent stenosis less than 3 months after angioplasty.

Sulfur dioxide mediated one-pot, three- and four-component syntheses of polyfunctional sulfonamides and sulfonic esters: study of the stereoselectivity of the ene reaction of sulfur dioxide.

The ene reaction of sulfur dioxide with enoxysilanes or with allylsilanes generates silyl sulfinates that can be brominated (Br(2) or NBS) or chlorinated (NCS or Cl(2)) to produce the corresponding sulfonyl halides. They react with primary and secondary amines or alcohols to give the corresponding sulfonamides and sulfonic esters, respectively. The hetero-Diels-Alder addition of sulfur dioxide to 1-oxy- or 1,3-dioxy-1,3-dienes generates zwitterions that add to enoxysilanes or allylsilanes giving silyl sulfinates that can be converted in situ into polyfunctional sulfonamides or sulfonic esters.

The subunit b dimer of the FOF1-ATP synthase: interaction with F1-ATPase as deduced by site-specific spin-labeling.

We have used site-specific spin-labeling of single cysteine mutations within a water-soluble mutant of subunit b of the ATP synthase and employed electron spin resonance (ESR) spectroscopy to obtain information about the binding interactions of the b dimer with F1-ATPase. Interaction of b2 with a delta-depleted F1 (F1-delta) was also studied. The cysteine mutations used for spin-labeling were distributed throughout the cytosolic domain of the b subunit.

First asymmetric synthesis of the cyclohexanone subunit of baconipyrones A and B. Revision of its structure.

[reaction: see text] An asymmetric synthesis of the 3,5-dihydroxycyclohexanone subunit of baconipyrones A and B, as well as that of the hydroxydiketone subunit of baconipyrones C and D ((-)-(4S,6S)-4,6-dimethyl-5-hydroxynonan-3,7-dione), is described. Key steps include sulfur dioxide-induced additions of enoxysilanes to 1,3-dioxy-1,3-dienes, followed by retro-ene desulfitations (retro-ene elimination of SO(2)).

Glycosidase inhibitors as potential HIV entry inhibitors?

A few alpha-L-fucosidase inhibitors and alpha-D-glucosidase inhibitors have shown in vitro anti-HIV activities, that have been attributed to their ability to inhibit HIV entry. The mechanism of action of inhibitors such as 1-deoxynojirimycin (1) is not clearly established. One possible hypothesis is that the glycosidase inhibition affects the final conformation of the glycoproteins involved in the virus/cell recognition and fusion phenomena.