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Four airport malaria cases have been observed in the vicinity of the Roissy-Charles-de-Gaulle International Airport, Paris, France. These cases were geographically very close to each other and clustered in a short period of time during the summer of 1999. The phenotype and genotype of the Plasmodium falciparumisolates obtained from these patients were determined in order to know whether a single mosquito could have infected more than one subject. The genomic characterisation of isolates was performed using the polymorphic markers merozoite surface protein 1 (Mspl) and merozoite surface protein2 (Msp2) genes, the κ and ϖ repeats domains of cg2and the dihydrofolate reductase (DHFR) genotypes. Results showed identical genotypes for isolates 1, 2 and 4 whereas the genotype of isolate 3 differed at one locus. The molecular analysis was consistent with the hypothesis that all patients could have been bitten by the same mosquito and that patient 3, may have received a different clone and an additional species. In vitrosusceptibility data did not confirm or rule out this hypothesis because isolates had the same profile of susceptibility to the tested drugs.

L'influence d'ajouts de vanadium (1; 1,6; 2,1; 2,3 % at) sur les propriétés des matériaux rapidement solidifiés est étudiée ici. Ces additions provoquent une diminution de la température de Curie, tandis que la cristallisation de la phase amorphe contenue dans les rubans est retardée. Pour l'instant aucune évolution microstructurale n'a pu être décelée. La coercitivité des aimants de type I est maximale pour 1 % d'ajout. Pour les aimants de type II et au delà de 1.6 %, l'ajout de vanadium s'accompagne d'un accroissement de la coercitivité et d'une modification des mécanismes d'aimantation.

Fibre-cement products had been widely used in the world due to their versatility as corrugated and flat roofing materials, cladding panels and water containers presented in large number of building and agriculture applications. The main reason for incorporating fibres into the cement matrix is to improve the toughness, tensile strength, and the cracking deformation characteristics of the resultant composite. One of the drawbacks associated with cellulose fibres in cement application is their dimensional instability in the presence of changing relative humidity. The objective of the present work is to evaluate the effect of surface treatment of eucalyptus cellulose pulp fibres on the processing and dimensional changes of fibre-cement composites. Surface modification of the cellulose pulps was performed with methacryloxypropyltri-methoxysilane (MPTS), aminopropyltri-ethoxysilane (APTS) and n-octadecyl isocyanate, an aliphatic isocyanate (AI), in an attempt to improve their dimensional instability into fibre-cement composites. X-ray photoelectron spectroscopy (XPS) showed the chemical changes occurred at the surface, and contact angle measurements showed the changes in the surface energy. MPTS-and AI-treated fibres presented lower hydrophilic character than untreated fibres, which led to lower water retention values (WRV). APTS increased the water retention value of the pulp and improved the capacity of hydrogen bonding of the fibres. MPTS-and AI-treated fibres led to low final water/cement ratios and reduced volume changes after pressing. MPTS-treated fibres decreased the water and dimensional instability of the fibre-cement composites, while the contrary occurred with APTS-modified and AI-modified fibres.These results are promising and contribute for new strategy to improve processing and stability of natural fibres-reinforced cement products.

The adhesion of infected red blood cells (IRBCs) to the cell lining of microvasculature is thought to play a central role in the pathogenesis of severe malaria. Individual IRBC can bind to more than one host receptor and parasites with multiple binding phenotypes may cause severe disease more frequently. However, as most clinical isolates are multiclonal, previous studies were hampered by the difficulty to distinguish whether a multiadherent phenotype was due to one or more parasite population(s). We have developed a tool, based on cytoadhesion assay and GeneScan genotyping technology, which enabled us to assess on fresh isolates the capacity of adherence of individual P. falciparumgenotypes to human receptors expressed on CHO transfected cells. The cytoadhesion to ICAM-1 and CD36 of IRBCs from uncomplicated and severe malaria attacks was evaluated using this methodology. In this preliminary series conducted in non immune travelers, IRBCs from severe malaria appeared to adhere more frequently and/or strongly to ICAM-1 and CD36 in comparison with uncomplicated cases. In addition, a majority genotype able to strongly adhere to CD36 was found more frequently in isolates from severe malaria cases. Further investigations are needed to confirm the clinical relevance of these data.

Abstract The efficiency of cyclohexane oxidation with hydrogen peroxide catalyzed by vanadyl acetylacetonate at 40 °C and atmospheric pressure is enhanced by glyoxal additive. The process selectively produces a mixture of cyclohexyl hydroperoxide, cyclohexanol, and cyclohexanone with a high rate (up to 4400 catalyst turnover number). Cobalt(

Allylic substitution of PhCH(OAc)CH&dbd;CHPh by CH2(COMe)2 in a basic MeOH/H2O mixture could be achieved in the absence of a palladium catalyst and lead to a mixture of PhCH(CH(COMe)2)CH&dbd;CHPh and PhCH(OMe)CH&dbd;CHPh in 40% and 55% yields, respectively. The process is induced by water, and nucleophilic attack addition occurred on a stabilized carbocation as the intermediate. Addition of a catalytic amount of PdCl2(CH3CN)2 did not accelerate the reaction but improved the selectivity, and PhCH(CH(COMe)2)CH&dbd;CHPh was then obtained in 92% yield while PhCH(OMe)CH&dbd;CHPh was observed in trace amounts. An ESI-MS analysis of the reaction mixture led us to assume that a palladium acetylacetonate complex is involved in the formation of PhCH(CH(COMe)2)CH&dbd;CHPh.

The present study was undertaken to explore the antimalarial effect of a series of dicatecholate iron chelators. They may be made more or less lipophilic by increasing or reducing the length of the R substituent on the nitrogen. In vitro activity against the W2 and 3D7 clones of Plasmodium falciparum, toxicity on Vero cells and toxicity on uninfected erythrocytes by measure of the released haemoglobin were assessed for each compound. These findings were compared with the ability of iron(III), iron(II) and ferritin to reverse the inhibitory effect of catecholates. This study shows that increased lipid solubility of catecholate iron chelators does not lead to improved antimalarial activity. However, their activity is well correlated with their interaction with iron and with their toxicity against Vero cells. This study demonstrates a potent antimalarial effect of FR160 (R = C9H19) on five different strains of P. falciparum in vitro. FR160 inhibited parasite growth with an IC50 between 0.8 and 1.5 micro M. The effects of FR160 on mammalian cells were minimal compared with those obtained with malaria parasites. FR160 acted on parasites at considerably higher rates than desferrioxamine, and at all stages of parasite growth. The drug was more effective at the late trophozoite and young schizont stages, although FR160 affected rings and schizonts as well. Ascorbic acid, a free radical scavenger, reduced the activities of FR160 and artesunate. FR160 might induce formation of free radicals, which could explain why FR160 antagonized the effects of artesunate and dihydroartemisinin.

Quinone methides act as important intermediates in organic syntheses, as well as in chemical and biological processes; however, examples of such isolated species are scarce as a result of their high reactivity. Phenol tautomers (keto form of phenol) are also important intermediates in several organic and organometallic reactions; nevertheless, isolated complexes are rare. This Account reviews the recent progress on the synthesis and reactivity of iridium and rhodium o-quinone methide complexes as well as on iridium-mediated ortho functionalization of phenols. This reaction was at the origin of the discovery of a general synthetic procedure to prepare the first metal-stabilized o-quinone methide.

Purpose:: The aim of this study was (1) To determine the value of fine-needle aspiration cytology (FNAC) in children with persistent or suspicious peripheral lymphadenopathy and (2) to analyze whether a history of previous malignancy influenced the accuracy of FNAC. Methods:: A retrospective study in an Academic Children's Hospital of 73 FNACs of peripheral lymph nodes in 64 patients (35 boys and 29 girls; median age, 9 years; range, 15 months to 20 years) was performed between 1992 and 1997. Eleven patients were excluded because aspirated material appeared inadequate. Outcome was compared with results of subsequent surgical biopsies, clinical follow-up, or both. Patients were divided into group A ''de novo'' lymphadenopathy (n = 39) and group B lymphadenopathy and a history of previous malignancy (n = 23). Results:: Group A: FNAC showed a benign diagnosis in 25 cases, a malignancy in 13, and was inconclusive in 1. Outcome was false-negative in 2 and false-positive in 1. Sensitivity and specificity were 86% and 96%, respectively. FNAC helped avoid additional surgical procedures in 27 cases (61%). However, if FNAC showed malignant lymphoma, open biopsy was inevitable (8 of 13) to establish proper classification. Group B: FNAC showed a benign diagnosis in 10 cases and a malignancy in 13. Outcome was false-negative in 1, and false-positive in 1. Sensitivity and specificity were 92% and 90%, respectively. FNAC helped avoid additional surgical diagnostic procedures in 25 cases (86%). Conclusions:: (1) Fine-needle aspiration cytology is a rapid, simple and accurate diagnostic procedure to differentiate between benign and malignant peripheral lymphadenopathy in children. FNAC can avoid open biopsy in at least 60% of cases. (2) A history of previous malignant disease does not influence the accuracy of the test.

We present new kinds of conducting gels of octylthiophene. Contrary to the gels previously obtained in our laboratory, they present two “high” gelation thresholds (i.e., related to high crosslink ratios). Consequently, systems close to the gelation threshold can be prepared with accuracy. Furthermore, they are calibrated and regioregular:  The length and the regioregularity of the chain segments between adjacent cross-links are fully controlled. They are prepared by chemical polycondensation of monodisperse regioregular [(head-to-tail (HT)] oligo(octylthiophene)s with tribromobenzene. For the preparation of these gels, two kinds of regioregular oligomers are synthesized:  linear (from dimer to hexamer) and “star” oligo(octylthiophene)s. The two star oligomers are made of a benzene ring trisubstituted in meta positions by a regioregular (HT) segment of respectively six (E6) and twelve (E12) octylthiophenes. The structural properties of the oligomers are studied by ¹H and ¹³C NMR spectroscopy; information concerning their conformation is reported. The optical properties (UV−vis absorption and fluorescence) of the star oligomers are compared with that of the linear oligomers. A linear evolution of the energy of the fluorescence transitions of the linear regioregular oligo(octylthiophene)s with the reverse of thiophene number is demonstrated for the first time. The Stille coupling chosen to prepare the gels from the oligomers is studied to determine the experimental conditions allowing both the good solubility of large clusters formed during the gel preparation and the good yield of the coupling reaction. A first series of 14 networks is reported. It is characterized by two gelation thresholds that are very high, as expected, but very close one from another. A strategy is proposed to increase the distance between the two gelation thresholds in the coming series.

Two categories of fully conjugated poly(octylthiophene) gels have been prepared from well-characterized small molecules for various crosslink ratios, R, and for different crosslink functionalities, f. These gels swell and can be doped. Their statistical structure is determined by the variable α= f.R. Gel fraction, swelling ratio and proton-NMR specific structural parameter display master curves of variations versus α. The state of deformation of gels swollen at equilibrium has been described. At temperatures lower than 170°C, the gels are weakly semi-crystalline. The states of crystallinity, observed at various temperatures depend on α. The conductivity of doped dry gels is governed by intermolecular hopping processes (model of hopping between conducting clusters) and is found to also depend on α. At room temperature, crystalline domains size, conducting domains size and macroscopic conductivity show a maximum for the gel prepared at α= 0.003, disclosing that these quantities are correlated.

Two categories of fully conjugated poly(octylthiophene) gels have been prepared from well-characterized small molecules for various crosslink ratios, R, and for different crosslink functionalities, f. These gels swell and can be doped. Their statistical structure is determined by the variable α= f.R. Gel fraction, swelling ratio and proton-NMR specific structural parameter display master curves of variations versus α. The state of deformation of gels swollen at equilibrium has been described. At temperatures lower than 170°C, the gels are weakly semi-crystalline. The states of crystallinity, observed at various temperatures depend on α. The conductivity of doped dry gels is governed by intermolecular hopping processes (model of hopping between conducting clusters) and is found to also depend on α. At room temperature, crystalline domains size, conducting domains size and macroscopic conductivity show a maximum for the gel prepared at α= 0.003, disclosing that these quantities are correlated.

Extraskeletal myxoid chondrosarcorna is a rare tumor that usually occurs in the soft tissues of the extremities and for which until now orbital involvement has never been reported. This report deals with an extraskeletal myxoid chondrosarcoma of the orbit in a 14-year-old boy. The prognosis and differential diagnosis are discussed.

Chocolate cysts or cholesterol granulomas affecting the orbit are rare in the literature. As far as the authors know, no more than 20 cases have been published since 1829. In a period of five years five patients with this disorder have been treated in the Amsterdam Orbital Centre. These patients are described and make the total of published cases up to 25.

Different types of lattice defects have been studied by transmission electron microscopy (TEM) at 100 and 200 kV in a sample of natural marcasite. The most frequently occurring Burgers vectors are b=[001], [100] and <101>. Dislocations with large Burgers vectors (b=<110> and <111>) have also been characterized: these are possibly split. Interactions between the different dislocations result in a build-up of dislocation networks. Dislocation structures show that the sample has undergone a strong recovery. These observations are confirmed by metallographic and scanning electron microscopy (SEM) observations after chemical etching.

The combinations of chloroquine plus chlorpromazine and chloroquine plus prochlorperazine were evaluated in vitro for potentiation against isolates of Plasmodium falciparum. Potentiation was observed against all chloroquine-resistant isolates. There was no potentiation against 8 of 10 chloroquine-susceptible isolates. The results indicated that the phenothiazines can potentiate chloroquine action against resistant parasites found in natural conditions.

The disposition of monodesethylamodiaquine was studied in four healthy subjects after a single oral dose of 10 mg/kg amodiaquine base.

Naturally occurring malaria, arbovirus infection and hepatitis in monkeys can be a hazard for the investigator and might interfere with the outcome of experiments.63 young adult Macaca fascicularisfrom Malaysia were screened for these infections. About 1 year after their arrival in France, parasitaemia due to Plasmodiumspp., was present in 6·4% of the animals and specific antibodies in 55·5%. 19 of 35 initially positive monkeys were tested again 2 years later. Parasitaemia was found in 1 of 4 monkeys and antibodies in 11 of 19 monkeys which were initially positive. 9 of the monkeys initially tested had low titres of antibodies to the Flavivirusgenus. All animals were negative for the hepatitis B surface antigen and anti-HBc. The prevalence of IgG antibodies against hepatitis A was 46·0%. The implications in terms of control are discussed.

The literature on diffuse sclerosing osteomyelitis of the mandible has included at least two groups of lesions:(1) those from which bacterial infectious agents are rarely isolated (chronic-tendoperiostitis); and (2) those from which bacteria are readily isolated (true diffuse sclerosing osteomyelitis). The latter should be distinguished from secondarily infected florid osseous dysplasia. In this article the features of 16 patients with sclerotic jawbone lesions associated with symptoms of infection are analyzed. Eleven patients showed a large area of sclerosis of the mandible that was not restricted to the alveolar process and was surrounding an infectious focus. The histologic pattern revealed a deposition of reactive bone. These lesions are considered to represent true diffuse sclerosing osteomyelitis. The remaining five patients showed sclerotic lesions restricted to the alveolar process in one or more quadrants of the jaws. Apart from inflammation and reactive changes, histologic pattern revealed a fibroblastic stroma with bone and cementum-like structures that are formed by metaplasia. These lesions are considered to represent secondarily infected florid osseous dyplasia.

A series of alkylated phenols (phenol, 3,5-dimethylphenol and 3,4-dimethylphenol) were complexed by the [Cp*Ir(solvent)3][BF4]2 (1) unit prepared in situ; subsequent treatment with NEt3 produced the (oxo-η⁵-cyclohexadienyl)iridium complexes [Cp*Ir(η⁵-C6H3R2O)][BF4] [R = H (2); R = Me (3, 4)]. The X-ray molecular structure of 3 was determined. These (oxo-η⁵-cyclohexadienyl)iridium derivatives react with NaOMe in methanol to give the novel iridium cyclohexadienone complexes [Cp*Ir{η⁴-C6H3R2O(OMe)}] [R = H (5); R = Me (6, 7)] in 75−90% yield with nucleophilic attack occurring exclusively at the ortho-position relative to the C&dbd;O function. Addition of HBF4·Me2O to these iridium cyclohexadienone complexes 5−7 affords the starting material (oxo-η⁵-cyclohexadienyl)iridium derivatives 2−4 with MeOH. Further exposure to HBF4·Me2O produces the corresponding phenolic compounds [Cp*Ir(η⁶-C6H3R2OH)][BF4]2 (8−10); these chemical reactions are accompanied with hapticity changes η⁴ → η⁵ → η⁶ of the coordinated π-hydrocarbon. The novel iridium cyclohexadienone complexes 5−7 can be oxidized easily by iodine to produce the free cyclohexadienones which rearomatize to give the free ortho-substituted phenols 11−13 in yields from 80% to quantitative.

Treatment of [Cp*Ir(η⁵-PhO)][BF4] (1) with hydride, deuteride, and C-, N-, and S-centered nucleophiles affords the stable η⁴-phenol tautomers of the type [Cp*Ir(η⁴-exo-2-(Nu)-C6H5O)] (2−6) {Nu = nucleophile}. In all cases regiospecific nucleophilic addition occurs at the ortho-position relative to C&dbd;O with exo-stereochemistry. The X-ray molecular structure of the first neutral phenol tautomer [Cp*Ir(η⁴-exo-2-(CH(COMe)2)-C6H5O] (4) was determined and provides valuable crystallographic information for an organic phenol tautomer. Oxidation of the novel dienone iridium complexes [Cp*Ir(η⁴-exo-2-(Nu)-C6H5O)] by iodine provided a different type of products depending dramatically on the nature and electron properties of the 2-exo-nucleophile. For instance R3C-, RO-, and R3P-centered nucleophiles gave the related ortho-functionalized phenols along with the starting material recycled in the form of [Cp*Ir(μ-I)I]2. In dramatic contrast N- and S-centered nucleophiles showed a retronucleophilic addition or C−Nu bond cleavage as demonstrated by complexes 5 and 6 to give the starting material identified spectroscopically and by X-ray structure as [Cp*Ir(η⁵-PhO)][I] (8). In the latter, a rationale involving a one-electron oxidation process is proposed to explain the experimental results.

Treatment of hydroquinone with [Cp*Ir(solvent)3][BF4]2 (1) in acidic medium afforded the stable π-bonded complex [Cp*Ir(η⁶-hydroquinone)][BF4]2 (2) in 93% yield. Complex 2 can be easily deprotonated by a base to give the related [Cp*Ir(η⁵-semiquinone)][BF4] (3) and [Cp*Ir(η⁴-p-benzoquinone)] (4) compounds, identified by spectroscopic methods. Further, the X-ray molecular structure of p-benzoquinone iridium complex 4 is reported; such compounds are rare in the literature. Complex 4 reacts with an excess of HBF4·Et2O to give the starting material 2 quantitatively. Interestingly, the chemical transformations from 2 to 4 and vice versa occur with facile reversible changes of the oxidation state from Ir(III) to Ir (I). On the other hand, the oxo−dienyl iridium complex [Cp*Ir(η⁵-2,6-dimethoxy-C6H3O)][BF4] (5), identified by spectroscopic methods and X-ray analysis, reacts with NaOMe in methanol to give unexpectedly but reproducibly the substituted o-benzoquinone iridium compound [Cp*Ir{η⁴-(3-methoxy)-o-benzoquinone}] (6). The solution behavior and the reactivity of 6, as well as a rationale explaining its formation, is advanced.

The antifols, inhibitors of the dihydrofolate reductase (DHFR), such as pyrimethamine and proguanil, have been used againstPlasmodium falciparumin the areas where chloroquine resistance is widespread. This use has selected resistant strains in Southeast Asia and South America. The resistance is correlated with point mutations in precise positions of the DHFR gene. A reliable semi-nested PCR diagnosis test was established and used to determine the genotypic features of 29 isolates ofP. falciparumoriginating from Africa. The results obtained by the PCR technique were compared with those of thein vitrodrug sensitivity test. Some isolates were found to be polyclonal. Among the mutations tested, only mutations on codon 108 which generate an asparagine induce a decrease in sensitivity to pyrimethamine and cycloguanil, whereas mutation on codon 59 strengthens resistance to both antifols. No mutation on codon 16 or codon 164 was found.

A combination of chloroquine and amlodipine, a derivative of 1,4-dihydropyridine calcium channel blocker, was tested against Plasmodium falciparum in vitro and P. yoelii in mice. The dextrorotary enantiomer of amlodipine, practically devoid of calcium channel blocking action, increased chloroquine accumulation inside the infected mouse erythrocytes and potentiated chloroquine action against the resistant strains of P. falciparum in vitro and P. yoelii in mice. Unlike the racemate, the dextrorotary amlodipine was not toxic to the host animal, even at the highest dose of 250 mg/kg. No potentiating effect was noted in the chloroquine-susceptible strains of P. falciparum. The results of this study indicate that chloroquine potentiation of amlodipine is probably independent of calcium channels and that a combination therapy of the dextrorotary enantiomer of amlodipine and chloroquine might be a potentially useful therapeutic strategy against chloroquine-resistant falciparum malaria.

The efficacy of a loading dose of 20 mg of chloroquine per kg of body weight per os given at intervals during the first day was evaluated in 27 patients in Madagascar with Plasmodium falciparum malaria. The conventional regimen of 25 mg/kg over 3 days (schedule 1) was thus compared with a regimen of 30 mg/kg over 2 days (schedule 2; one dose of 10 mg/kg followed by two doses of 5 mg/kg at 6-h intervals on the first day and two doses of 5 mg/kg at 12-h intervals on the second day) in terms of their clinical and parasitological efficacies, tolerance, and drug concentration-time curves. At 24 h schedule 2 gave higher chloroquine levels in blood, which induced a more rapid decrease in parasitemia. The time required for a 50% decrease in the initial parasitemia was shorter in patients on schedule 2 (14.3 +/- 1.6 h) than it was in patients on schedule 1 (35.5 +/- 5.4 h; P less than 0.01). Moreover, negative blood smears were obtained more rapidly with schedule 2 (50.8 +/- 3.7 h) than with schedule 1 (72 +/- 8.7 h). As predicted by the drug concentration-time curve, no high, potentially toxic peak drug concentration appeared and no adverse effects were observed with the loading dose regimen (schedule 2). These findings support the idea that a loading dose of 20 mg/kg given at intervals during the first 12 h is well tolerated and can be used to obtain a more rapid decrease in parasitemia and to shorten the treatment time of uncomplicated chloroquine-susceptible falciparum malaria in the field.

In this study, we examined the potential interactions between antimalarial (chloroquine, quinine, and mefloquine) and oxidant reagents. The data indicate that their effects enhance those of one another in vitro. The viability of Plasmodium falciparum in culture was assessed by [3H]hypoxanthine incorporation during 24 h of incubation in the presence of lactoperoxidase, glucose-glucose oxidase, hydrogen peroxide, chloroquine, quinine, and mefloquine, either alone or in combination. At subinhibitory concentrations, a significant inhibition was produced by the following combinations: lactoperoxidase plus hydrogen peroxide, lactoperoxidase plus glucose-glucose oxidase, lactoperoxidase plus hydrogen peroxide or glucose-glucose oxidase plus chloroquine or quinine but not with mefloquine. Deletion of any component from the system markedly decreased the toxic effect on P. falciparum. This toxic effect was not inhibited by catalase. These results indicate that the peroxidase-hydrogen peroxide system and antimalarial drugs can potentiate each other to inhibit the growth of P. falciparum.

Experimentally deformed pyrite monocrystals have been studied by TEM at 100 and 200 kV. One sample was strained in compression along the 〈111〉 axis at 400°C. The three slip systems {001}〈010〉 are equally activated; dislocations parallel to 〈110〉 have a 45°-mixed character and are dissociated in the glide plane into two colinear partials. In another sample deformed in the [001] orientation at 779°C the predominant slip system appears to be (001)[010]; the dislocations are mainly parallel to 〈100〉 and dissociated, the plane of dissociation depending on their edge or screw character. Dislocation loops formed by condensation of sulphur vacancies can be faulted or not. The fault vector leading to a very low defect energy has the same displacement vector as that of the growth defects observed in some natural pyrites.

The component α〈100〉 of b is generally normal to the defect plane. This dislocation is not glissile. Very rarely, this component is parallel to the fault plane. We have also observed partial dislocations, with b = ± R; these dislocations lie in the fault plane but never at the end of the stacking fault.ELECTRON MICROSCOPY STUDY OF DISLOCATIONS IN PYRITE (FeS) Natural pyrites (FeS2) from several sources have been studied by transmission electron microscopy at 100 kV. Total dislocations with Burgers vector b = α〈100〉 are identified. Partial dislocations bordering stacking faults (displacement vector R) have a Burgers vector that can be written as  [image omitted] The component a〈100〉 of b is gencrally normal to the tlefcct plane. ThisVery rarely, this component i R parallel to the fault We have also observed partial dislocations, with b = ± R; them dislocations dislocation is not glissile. plane lie in the fault plane but never at the end of the stacking fault.

Anaemia during malaria is not completely understood. Fourteen cases of anti-erythrocyte autoimmunisation with anti-I specificity were investigated in a Paris hospital during a period of 2 years. The patients lived in Gabon and had not been taking antimalarial chemoprophylaxis. All had chronic malaria (strongly positive antimalarial immunofluorescent antibody tests). All the recognised causes for anti-erythrocyte autoimmunity were excluded. One possible explanation for these observations is some sort of interaction between I antigen and Plasmodium,the result of which facilitated penetration of the erythrocyte by the malarial parasite.

The viability of Plasmodium falciparum in culture was assessed by [3H]hypoxanthine incorporation during 24 h of incubation with lactoperoxidase, glucose-glucose oxidase, hydrogen peroxide, halides, or thiocyanate, alone or in combination. Synergistic inhibition was produced by the following combinations: lactoperoxidase plus hydrogen peroxide, lactoperoxidase plus glucose-glucose oxidase, and lactoperoxidase plus hydrogen peroxide plus halides or thiocyanate. These inhibitory effects were reversed by catalase and glutathione. The presence of plasmodial crisis forms inside the erythrocytes suggests that the oxygen-dependent microbicidal system of phagocytes has a killing effect.

The virulence of B. gingivalis strain W83 was studied in an experimental animal model. Cells grown overnight, washed and resuspended in broth, were injected intradermally or subcutaneously in the back of guinea pigs, rats and mice. This strain proved to be very virulent, causing a severe plegmonous abscess in guinea pigs. Also in mice, which are thought to be resistant to infections with black-pigmented Bacteroides strains, the same type of infection could be induced. Rats proved to be rather insensitive. The model presented can be used as a simple virulence test for these anaerobic bacteria.

5,6,7,8-Tetrahydro-2-naphthol (3) and β-estradiol (1) gave η⁶-arene complexes using [Cp*Ir(solvent)3][BF4]2 (4) prepared in situ; subsequent O-deprotonation with NEt3 produced the corresponding complexes [Cp*Ir(oxo-η⁵-dienyl)][BF4] (5 and 6a,b). In the case of the complexed hormone, the Cp*Ir moiety coordinates the A-ring either α (metal down, 6a) or β (metal up, 6b) relative to the methyl group at C(13). The X-ray molecular structure of the α-isomer 6a was determined. These (oxo-η⁵-dienyl)iridium derivatives 5 and 6a react with NaOMe in methanol at −40 °C to give respectively the novel iridium cyclohexadienone complexes [Cp*Ir(methoxy-η⁴-dienone)] (7a and 8a) in 95 and 91% yields, respectively, with nucleophilic attack occurring exclusively at the ortho-position relative to the C&dbd;O function. The novel iridium cyclohexadienone compound of the complexed steroid 8a can be oxidized easily by iodine to produce 2-methoxyestradiol (2) in 60% overall yield from β-estradiol. This efficient organometallic procedure is preferable to the classical organic procedure, which requires five steps and affords 2 in less than 5% yield.

To determine virulence factors of isolates of Plasmodium falciparum and the potential role of cytokines in cerebral malaria, 46 Malagasy patients presenting with cerebral (n = 10), severe (n = 10), and uncomplicated (n = 26) malaria were enrolled in a study. The capacity of 21 of 46 P. falciparum isolates to form rosettes in vitro and to adhere to human umbilical vein endothelial cells (HUVECs) that express intercellular adhesion molecule-1 receptors and to C32 amelanotic melanoma cells that express mainly CD36 receptors was investigated together with the effects of tumor necrosis factor alpha (TNF-alpha), granulocyte macrophage-colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), and IL-6 alone and in two-by-two combinations on the cytoadherence of infected erythrocytes to HUVECs. Plasma levels of these cytokines were also measured in the patients at admission. The percentage of rosette formation was higher for the isolates from patients with cerebral (n = 6; 19.5%) and severe (n = 6; 30.5%) malaria than for those from patients with uncomplicated malaria (n = 9; 5%) (P < 0.002). The cytoadherence properties of the isolates did not differ among the three groups whatever the target cell used, but adherence to melanoma cells was systematically higher than that to HUVECs. Adhesion to HUVECs was increased more after TNF-alpha stimulation than after GM-CSF, IL-3, or IL-6 stimulation (P < 0.01). Only the combination of TNF-alpha and IL-3 enhanced cytoadherence more than TNF-alpha used alone (P < 0.02). No difference in the modulation of cytoadherence by cytokines was found in relation to the severity of the disease. TNF-alpha and IL-6 levels in peripheral blood were higher in the patients with cerebral and severe malaria than in the patients with uncomplicated malaria (P < 0.005). Most of the patients' sera contained little or no IL-3 or GM-CSF. Our results challenge the role of intercellular adhesion molecule-1 as the principal receptor mediating the cytoadherence of P. falciparum-infected erythrocytes and contrast with data obtained in the murine model.