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Environmental fungi are globally ubiquitous and human exposure is near universal. However, relatively few fungal species are capable of infecting humans, and among fungi, few exposure events lead to severe systemic infections. Systemic infections have mortality rates of up to 90%, cost the US healthcare system $7.2 billion annually, and are typically associated with immunocompromised patients. Despite this reputation, exposure to environmental fungi results in a range of outcomes, from asymptomatic latent infections to severe systemic infection. Here we discuss different exposure outcomes for five major fungal pathogens: Aspergillus, Blastomyces, Coccidioides, Cryptococcus, and Histoplasma species. These fungi include a mold, a budding yeast, and thermal dimorphic fungi. All of these species must adapt to dramatically changing environments over the course of disease. These dynamic environments include the human lung, which is the first exposure site for these organisms. Fungi must defend themselves against host immune cells while germinating and growing, which risks further exposing microbe-associated molecular patterns to the host. We discuss immune evasion strategies during early infection, from disruption of host immune cells to major changes in fungal cell morphology.

Resume Nous donnons les grandes lignes d'une demonstration de la conjecture de Goncharov et Manin qui predit que les periodes relatives des espaces des modules M 0 , n des courbes de genre 0 avec n points marques sont des valeurs zetas multiples. Pour citer cet article : F.C.S. Brown, C. R. Acad. Sci. Paris, Ser. I 342 (2006).

Resume Les versions uniformes des polylogarithmes classiques Li n ( z ) ont de nombreuses applications en mathematiques. Elles ont ete etudiees, sous diverses formes, par Ramakrishnan, Wojtkowiak, et Zagier entre autres. Dans cette Note nous expliquons comment construire, plus generalement, une version uniforme pour chaque polylogarithme multiple en une variable de facon systematique. Nous demontrons que les fonctions definies sont lineairement independantes, qu'elles satisfont aux relations de battage, et que toute version uniforme des polylogarithmes multiples en une variable s'obtient de cette facon. Pour citer cet article : F.C.S. Brown, C. R. Acad. Sci. Paris, Ser. I 338 (2004).

The aflatoxin biosynthetic pathway represents one of the est studied pathways of fungal secondary metabolism. Its lucidation is the result of over 30 years of study by cientists in many disciplines. For recent reviews on the hemistry of the pathway see articles by Bhatnagar et al. 1992) Minto and Townsend (1997), and Woloshuk and rieto (1997). Concern over the toxicity and carcinogenicty of aflatoxin has been the prime force driving research in his area. Aflatoxin B1 (AFB1) is the most potent naturally ccurring carcinogen known (Squire, 1989), and epidemioogical data implicate aflatoxin as a component of liver ancer in humans in certain parts of the world (Hall and ild, 1994). Although aflatoxins are not extremely toxic, onsumption of aflatoxin contaminated food by animals can ead to decreased weight gain, hemorrhaging, and suppression f the immune system (Miller and Wilson, 1994). Aflatoxins are produced by four species of Aspergillus: . flavus, A. parasiticus, A. nomius, and A. tamarii (Payne, 998; Kurtzman et al., 1986; Goto et al., 1996). From an gricultural standpoint, the two most significant fungi are

Chimeric proteins consisting of the VP2 capsid protein of human parvovirus B19 and defined linear epitopes from human herpes simplex virus type 1 and mouse hepatitis virus A59 inserted at the N-terminus and at a predicted surface region were expressed by recombinant baculoviruses. The chimeric proteins expressed the inserted epitopes and assembled into empty capsids. Immunoelectron microscopy indicated that the epitopes inserted in the loop were exposed on the surface of the chimeric particles. The chimeric capsids were immunogenic in mice and antibodies specific for the inserted sequences were induced. In the case of MHV, antibodies were produced that recognized the epitope in the context of native virus. Mice immunized with the chimeric capsids were partially protected against a lethal challenge infection with either MHV or HSV.

An international collaborative study was conducted at ten sites to examine the performance of enzyme immunoassays (EIAs) for the quantitation of IgG1, IgG2, IgG3, IgG4 and total IgG anti-Haemophilus influenzae type b (Hib) capsular polysaccharide in human serum. All groups used the same reagents: microtiter plates coated with polyribosylribitol phosphate (PRP) conjugated to poly-L-lysine (PLL), reference, control and test human sera, biotin-conjugated International Union of Immunological Societies (IUIS)-documented monoclonal anti-human IgG1-4 and IgG Pan detection antibodies, avidin-peroxidase and TMB substrate. Initial mixing of soluble PRP antigen or an equal volume of buffer with the 20 test sera prior to analysis confirmed PRP antigen specificity in all five EIAs with greater than 80% competitive inhibition at most sites. Positive correlation between the total IgG anti-Hib and sum of IgG1-4 anti-Hib was demonstrated (r2 = 0.99, Y = 1.13X -0.15). Good agreement was shown between the total IgG anti-Hib as measured by EIA and the total Hib-specific antibodies measured by the current radiolabeled antigen binding assay (r2 = 0.97, Y = 4.6X -5.8). Assay parallelism was demonstrated with an average interdilutional %CV of 22% and parallel dose-response curve slopes. The interdilutional %CVs were calculated as an average per sample of the variation of microgram/ml (corrected for dilution) at different dilutions per laboratory for all participating sites. The interlaboratory variation was the only performance parameter studied that exceeded the target level of 35% CV in all IgG1-4 and total IgG anti-Hib assays. IgG subclass distributions in the test sera demonstrated a predominance of IgG1 anti-Hib in the pediatric serum pools and IgG2 anti-Hib in the adult sera, with low but detectable levels of IgG3 and IgG4 anti-Hib in each group.

B. Dresser’,‘, E. Pope’,*, N. Chin3, J. Liu*, N. Loskutoff4, E. Behnke3, C. Brown4, M. McRae’, C. Sinoway3, M. Campbell’, K. Cameron’, R. Evans’, 0. 0wens3, C. Johnson’, M. Cedars* ‘Cincinnati Zoo Center for Reproduction of Endangered Wildlife (CREW), 3400 Vine Street, Cincinnati, OH 45220 USA; *University of Cincinnati College of Medicine, Department of Obstetrics and Gynecology, Cincinnati, OH; 3The Christ Hospital, Cincinnati, OH; 40maha’s Henry Doorly Zoo, Omaha, NE; 5Bethesda Hospital, Cincinnati, OH.

The Durham route to polyacetylene provides, for the first time, the possibility of controlling the crystalline structure of this fascinating material. This control will enable us to probe the role of the redox doping and relative spatial co-ordinates of the chains in determining electrical conductivity. Before this can be accomplished it is necessary to understand the nature of the order within the variety of materials which can now be produced. Material produced from quiescent films can have a range of structures from largely amorphous (inasmuch as a structure composed of rigid rods can exhibit disorder) to slightly crystalline. By stretching the precursor film during transformation highly oriented, crystalline polyacetylene can be produced. This offers a range of structures and should enable the separation of inter- and intra-chain electronic effects for the first time.

The structure of polyacetylene produced from a precursor polymer is compared with that of polymer produced by a soluble Ziegler-Natta catalyst. X-ray diffraction shows that the precursor polyacetylene can be produced with a wide range of ordering from apparently amorphous to crystalline, although the ordering is never as high as that of polymer produced by the Ziegler-Natta route. An increase in ordering, as measured by X-ray peak width, has been observed during isomerization; this contrasts with normal polyacetylene where no change in order is found. Both forms of polyacetylene show a gradual shift in the interchain d -spacing from 395 pm ( cis/trans mixed) to 365 pm ( trans ). Since only a single peak is found in this region the cis - and trans -forms are not phase-separated on a scale of 3 nm or more. Small-angle X-ray scattering also indicates that discrete crystalline and amorphous regions, as found in polyethylene, are not present

The processes involved in the thermal transformation of ‘Durham polyacetylene precursor’, poly[[5,6-bis(trifluoromethyl)-bicyclo[2,2,2]octa-5,7-diene-2,3-diyl]-1,2-ethenediyl], to all- trans polyacetylene have been studied. Above about 100°C the reactions are virtually concurrent, but at 50°C one can distinguish a first-order elimination ( k = 7.6 × 10 −4 s −1 ), effusion of the elimination product ( D = 4 × 10 −9 cm 2 s −1 ), and a first order cis-trans isomerization ( k = 1.5 × 10 −5 s −1 ). The isomerization is very sensitive to traces of oxygen below 80°C, but at higher temperatures this is less pronounced and the reaction becomes approximately second order. Isomerization is generally more facile in the less ordered Durham polymer than in polymers from the Shirakawa route.

Human red blood cells (RBCs), transformed by incubation with the amphiphatic compound lysolecithin from their normal discocyte shape into echinocytes, have increased rates of agglutination in the presence of either poly- l -lysine (PLL) or soybean agglutinin (SBA). Removal of lysolecithin by washing caused a reversal of shape back to the discocyte configuration and a lowering of agglutination rates. Methochlorpromazine, another amphiphatic echinocytogenic substance produced a similar increase in agglutination rates, suggesting that increased agglutinability may be a general property of echinocytes. Lysolecithin treatment of RBCs caused a decrease in the binding of cationized ferritin (CF) particles/μm2 of RBC surface. The decrease in CF binding is due to a rearrangement of negative charge bearing molecules on the RBC surface rather than shedding of charged groups. These observations support the hypothesis that integral membrane proteins which bear negative charges and receptors are associated with a cytoskeleton within the red cell. Alterations in cell shape which result in distortion of the cytoskeleton may cause a redistribution of integral membrane proteins which bear charged groups at the RBC surface.

Polyacetylene prepared by the Shirakawa route is a mat of crystalline fibrills, which are capable of being oxidized or reduced to a highly conducting state. Polyacetylene can also be produced from a soluble precursor polymer by a thermally driven transformation reaction (the ‘Durham’ route) as a solid, coherent film. This transformation consists of the elimination of a substituted benzene unit followed by the isomerization of the largely cis polyacetylene produced to a disordered trans isomer. We have studied the effect of different transformation conditions and from these studies it is possible to gain an insight into these processes. Techniques such as caloremetry, infrared, resonance Raman and optical spectroscopy, e.s.r., X-ray diffraction and electrical conductivity have all been used to probe the transformation and the product. The resultant information gives a consistent picture of the overall transformation processes detailed above but also shows an ordering associated with higher transformation temperatures. A thorough knowledge of these processes enables the orientation of the precursor to produce highly crystalline material.

An investigation has been carried out aimed at developing a process for the growth of large crystals of synthetic quartz using silica-rich rocks native to the United Kingdom as the raw material. As a result of this work the effect of impurities on the habit and quality of the crystals has been determined. The role of aluminium as a key impurity has been proved and the darkening produced by X-irradiation has been used to study the distribution of impurities in the synthetic quartz. Recent work has thrown further light on the manner in which aluminium, possibly associated with another element, is incorporated in the quartz structure.