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Local exchange-correlation functionals are defined for different systems with spherical symmetry, by requiring that they reproduce the correct exchange-correlation energy and exchange-correlation potential (up to a constant). For comparison, the results with the uniform electron gas local density approximation and a generalized gradient approximation are also shown.

Summary The transition structure and transition vector for carbon dioxide hydroxylation in presence of zinc coordinated with three ammonia molecules have been characterized at a high basis set level. Following the directions of the transition vector the reactants appear to make a rotatory-like motion: the zinc-oxygen bonds with carbon dioxide and hydroxyl ion change antisymmetrically, while the linearity of carbon dioxide is lost and the hydroxide attacks the electrophilic center; as a result, the hydroxide moiety in bicarbonate is not directly bound to zinc in the product.

Summary Varus deformity of the knee is common in young children who have suffered from fulminating purpura. This study was directed at the anatomic features of the vascularisation of the upper end of the tibia that might account for such deformation. It was based on the dissection of 28 anatomic specimens prepared by injection of Indian ink into the vascular trunk. 16 specimens were diaphanised for better analysis of the intracartilaginous distribution of the vessels. The study showed that the vascularisation of the medial condyle of the tibia is poor and of terminal nature, which may explain the occurrence of ischemic growth disorders following fulminating purpura.

Starting from a specific historical example, that of colonial Algeria, the paper seeks to examine religious movements which play a political role. Too often such movements have been viewed either as being only political or as utilising religion simply as a mask. It is argued here that religious movements having apparent political functions benefit (to the extent that they are religious) from being studied in contrast to other non-religious movements having similar or comparable functions in the same society at the same time (or in other societies with which comparison would appear justified). It is only in this way that one can see how the relation between the political and religious fields function. It is also in this way alone that we are able to see at what price (that of the relative autonomy of the religious field) the objective domination and manipulation of the religious by the political comes about. In studying societies which claim to be Islamic, it is particularly important to break with orientalist notion of the indivisibility of the religious and political, which obscures the real relationship between the two spheres.

What is a local viewpoint of delocalized bonds? We try to provide an answer to this paradoxical question by investigating representative conjugated organic molecules (namely, allyl cation, trans-butadiene, and benzene) together with reference nonconjugated systems (ethylene and propene) by means of topological analysis of the electron localization function ELF. The valence attractors of the ELF gradient field are classified according to their synaptic order (i.e., connections with core attractors). The basin populations (i.e., the integrated density over the attractor basins) and their standard deviation, σ, have been calculated and are discussed. The basin populations and their relative fluctuations, defined as are sensitive criteria of delocalization. In the case of well-localized C—C or C=C bonds, λ ~0.4, whereas for delocalized bonds λ increases to about 0.5. Another criterion of delocalization is provided by the basin hierarchy, which is defined from the reduction of the localization domains. For most systems, delocalization occurs not only for neighboring carbon-carbon disynaptic attractor basins, but also for nearest neighbor disynaptic protonated attractor basins. Keywords: electron localization function, topological analysis, delocalization, population analysis.

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The purpose of this study was to determine the efficiency of semi-nested PCR in detecting hepatitis A virus (HAV) RNA. During a 2-year period (1990-1991), HAV RNA was searched for in shellfish from the French Brittany coasts using cRNA and vRNA probes. In January 1992, at the time of a hepatitis A outbreak, 28 stool samples were collected from infected patients (18 adults, 10 children) with anti-HAV IgM. Four samples from subjects with negative HAV serology were used as negative controls. Nucleic acid amplification (reverse-transcription-semi-nested PCR) was performed to detect HAV in stool. HAV RNA was purified by phenol-chloroform extraction and converted to cDNA using reverse transcriptase (Mu-MLV). After amplification, PCR products were visualized on an ethidium-bromide-stained gel and confirmed by hybridization with a specific digoxigenin-labelled oligoprobe. Samples were also studied by molecular hybridization with cRNA and vRNA probes. After onset of the illness, HAV RNA was detected over a longer time period by semi-nested PCR (16/28) than by hybridization (0/28). Even though biological diagnosis of hepatitis A will continue to rely on the detection of anti-HAV IgM, PCR should be useful in certain clinical cases (diagnosis of relapse) and for epidemiological and environmental monitoring of viruses.

The X-ray transform plays an important role in the integral geometry of trees. It transforms functions on the vertices into functions on the geodesics. In (Casadio Tarabusi, Cohen, and Picardello, Adv. in Math., to appear) a precise description of the domain and range of the X-ray transform was given. In this work we construct and analyze subsets of these function spaces which have a Banach space structure and on which the X-ray transform acts as an isometry. Questions concerning continuity on the space of geodesics are also studied.Copyright 1993, 1999 Academic Press

Electrochemotherapy combines bleomycin and local electric pulses that allow cell permeabilization and free access of bleomycin to its intracellular target. We report the first veterinarian clinical trial of electrochemotherapy in 12 cats with spontaneous large soft-tissue sarcomas that suffered relapse after treatment with conventional therapies. Permeabilizing electric pulses were delivered using external surface electrodes, as well as new needle-shaped electrodes that were designed to be inserted in tumours for more effective treatment of several-centimetre-thick tumour nodules. The electric pulses were applied to the tumours several times from 4 to 15-30 min after a bolus intravenous injection of 0.5 mg kg(-1) bleomycin. Tolerance to treatment was excellent without general side-effects. The cats showed local inflammatory reactions for a few days and disease stabilization lasted from 2 weeks to 7 months. One partial regression was observed, and the general absence of nodule volume decrease can be explained by local fibrotic reactions. Histological analysis of biopsies also revealed massive tumour cell death. The cats' lifespan increased (P≪0.001), with a mean survival time of 6.1 months (maximum 18 months) compared with 0.8 months (maximum 1.5 months) for a group of 11 untreated control cats displaying similar carcinological features. Electrochemotherapy is clearly effective as a salvage treatment for large spontaneous solid tumours in adverse clinical situations and this is promising for future applications.

The sodium salt of the dinucleoside phosphate d(GpG), dissolved in water, forms two mesophases which have been characterized, by optical microscopy, as being of the cholesteric (columnar chiral nematic, N*) and hexagonal (M) type.

A premature baby had severe hypertension associated with idiopathic arterial calcification of infancy. Despite the fact that there was laboratory evidence of renin-mediated hypertension, the disease was refractory to specific renin antagonist and failed to respond to conventional medical treatment. Prostaglandin E1(PGE1) infusion (dosage range 0.017–0.068 μg/kg/min) promptly controlled hypertension on two occasions. The drug was given for a total of 65 days and then stopped after the appearance of severe thrombocytopenia; other side effects included sporadic hyperthermia and irritability. Blood pressure was then stabilized satisfactory by a multiple-antihypertensive regimen. In the light of these findings, we believe that PGE1infusion is a possible therapeutic alternative for babies with idiopathic arterial calcification complicated by severe hypertension refractory to conventional treatment.

Using polyethylenglycol (PEG) as soluble supporting polymer, oligonucleotides have been prepared in high yield by an easy and fast procedure. The method looks promising for rapid synthesis of grams of short oligomers at reasonable cost.

Among a series of unmodified phosphodiester (PO)-oligodeoxynucleotides (PO-ODNs) complementary to some of the human immunodeficiency virus type 1 (HIV-1) regulatory genes, several PO-ODN sequences complementary to the vpr gene (PO-ODNs-a-vpr, where a-vpr is the antisense vpr sequence) emerged as potent inhibitors (at concentrations of 0.8 to 3.3 microM) of HIV-1 multiplication in de novo infected MT-4 cells, while they showed no cytotoxicity for uninfected cells at concentrations up to 100 microM. Unlike phosphorothioate counterparts, PO-ODN-a-vpr sequences were not inhibitory to HIV-2 multiplication in de novo infected C8166 cells and neither prevented the fusion between chronically infected and bystander CD4+ cells nor inhibited the activity of the HIV-1 reverse transcriptase in enzyme assays. Moreover, they were not inhibitory to HIV-1 multiplication in chronically infected cells. Delayed addition experiments showed that PO-ODNs-a-vpr inhibit an event in the HIV-1 replication cycle following adsorption to the host cell, but preceding reverse transcription. Structure-activity relationship studies indicated that the antiviral activity of the test PO-ODN-a-vpr sequences is not related to an antisense mechanism but to the presence, within the active sequences, of contiguous guanine residues. Physical characterization of the test PO-ODNs suggested that the active structure is a tetramer stabilized by G quartets (i.e., four G residues connected by eight hydrogen bonds).

Since the first electron spectroscopic (ESCA) studies dealing with substituents effects upon core ionization energies (I.E.) of organic compounds1, little has been published on the subject. This was probably because the reported data did not always seem very meaningful. The absolute I.E. values obtainable in the solid phase are not very certain and also, the "shake-up" phenomena and the consequent broadening of the bands, which affect the I.E. values2, were not always taken into account. None the less we think that ESCA is a valuable tool for the study of substituent effects, and in particular of the transmission of electronic effects in aromatic systems.

The analysis of the four lowest ionization energy values related to π MO's in diphenylsulphide and its o-o'-dimethyl and o-o-o'-o'-tetramethyl derivatives indicates that the conformation of the unsubstituted compound largely deviates from planarity, that this deviation increases with ortho-substitution and that the two phenyl rings in the tetramethyl derivative are nearly orthogonal to each other

Background: Individuals with primary renal glucosuria have persistent urinary glucose excretion in the presence of normal blood glucose levels, normal oral glucose tolerance test results and in the absence of any signs of a general renal tubular dysfunction. Primary renal glucosuria is postulated to be attributable to mutations in SGLT2 gene, which codes for an active transporter specific for d-glucose, sodium/glucose co-transporter type 2, expressed in the luminal membrane of S1 segment renal proximal tubule cells. Described inheritance patterns have included both autosomal dominant and autosomal recessive mechanisms. Some cases have been associated with selective aminoaciduria, distinctly unlike the generalized aminoaciduria seen in Fanconi's syndrome. We report the case of a 5-months-old girl with primary renal glucosuria associated with overexcretion of glutamic acid and aspartic acid, daughter of non-consanguineous parents, both without renal glucosuria. The magnitude of glucosuria was 6,5 g per day and quantitative urine amino acid screen revealed greatly increased levels of glutamic acid, 2955 nmol/mg Creat. (normal range 252-1280) and mildly increased levels of aspartic acid, 911 nmol/mg Creat. (normal range 230–685).Aim: To define the molecular basis of renal glucosuria, we performed the SGLT2 mutation analysis in this patient with primary renal glucosuria and urinary overexcretion of glutamic and aspartic acid.Methods: Genomic DNA was extracted from patient's perypheral blood; PCR amplification was performed using primers specific for the coding region of the SGLT2 gene. PCR aplicons were sequenced with SeqScape 1.o software.Results: Sequence analysis of SGLT2 gene (exons 1,2,3,5,7,8,12) revealed a compound heterozygosity for two SGLT2 mutations, one in exon 5, 525delC (A169fs186X) and the other in exon 7, G/A R267Q.Conclusion: These findings suggests that two novel mutations in the SGTL2 gene are responsible for a form of recessive renal glucosuria associated with selective aminoaciduria.

The title compound (±)‐(II), after enzymatic hydrolysis, gives the lyxo‐ and xylo‐derivatives D‐(II) and L‐(III) with 96% e.e.

Acid‐catalyzed addition of the pyranose (II) to the acetyl compound (I) yields the diastereomeric disaccharides (III)‐(VI) which are separated by preparative HPLC.

L-β-Deoxythymldine (L-dT), the optical enantiomer of D-β-deoxythymidine (o-dT), and L-enantiomers of nucleoslde analogs, such as 5-iodo-2′-deoxy-L-uridine (L-ldU) and E-5-(2-bromovinyl)-2′-deoxy-L-uridine (L-BVdU), are not recognized in vitro by human cytosolic thymldine kinase (TK), but are phosphorylated by herpes simplex virus type 1 (HSV-1) TK and inhibit HSV-1 proliferation in infected cells. Here we report that: (i) L-dT is selectively phosphorylated in vivo to L-dTMP by HSV-1 TK and L-dTMP Is further phosphorylated to the di- and triphosphate forms by non-stereospecific cellular kinases; (ii) L-dTTP not only inhibits HSV-1 DNA polymerase In vitro, but also human DNA polymerases α, γ, δ and ɛ, human Immunodeficiency virus reverse transcriptase (HIV-1 RT), Escherichia coll DNA polymerase I and calf thymus terminal transferase, although DNA polymerase β was resistant; (iii) whereas DNA polymerases β, γ, ɛ and e are unable to utilize L-dTTP as a substrate, the other DNA polymerases clearly Incorporate at least one L-dTMP residue, with DNA polymerase a and HIV-1 RT able to further elongate the DNA chain by catalyzing the formation of the phosphodiester bond between the incorporated L-dTMP and an incoming L-dTTP; (iv) incorporated L-nucleotides at the 3′-OH terminus make DNA more resistant to 3′←5′ exonucleases. In conclusion, our results suggest a possible mechanism for the inhibition of viral proliferation by L-nucleosides.

The enzymatic hydrolysis of the title compound (I) is found to be not regiospecific, affording the β‐olivopyranoside (II) predominantly together with smaller amounts of the β‐boivinopyranoside (III).